GERMAN AIRPLANE MOTORS
In a paper on “Aviation Motors,” presented by E. H. Sherbondy before the Cleveland section of the S. A. E. in June, 1917, the Mercedes and Benz airplane motor is discussed in some detail and portions of the description follow.
Fig. 244.—Side and End Sectional Views of Four-Cylinder Argus Engine, a German 100 Horse-Power Design Having Bore and Stroke of 140 mm., or 5.60 inches, and Developing Its Power at 1,368 R.P.M. Weight, 350 Pounds.
MERCEDES MOTOR
The 150 horse-power six-cylinder Mercedes motor is 140 millimeters bore and 160 millimeters stroke. The Mercedes company started with smaller-sized cylinders, namely 100 millimeters bore and 140 millimeters stroke, six-cylinders. The principal features of the design are forged steel cylinders with forged steel elbows for gas passages, pressed steel water jackets, which when welded together forms the cylinder assembly, the use of inclined overhead valves operated by means of an overhead cam-shaft through rocker arms which multiply with the motion of the cam. By the use of steel cylinders, not only is the weight greatly reduced, but certain freedom from distortion through unequal sections, leaks and cracks are entirely avoided. The construction is necessarily very expensive. It is certainly a sound job. In the details of this construction there are a number of important things, such as finished gas passages, water-cooled valve guides and a very small mass of metal, which is water-cooled, surrounding the spark-plug. Of course, it is necessary to use very high compression in aviation motors in order to secure high power and economy and owing to the fact that aviation motors are worked at nearly their maximum, the heat flow through the cylinder, piston, and valves is many times higher than that encountered in automobile motors. It has been found necessary to develop special types of pistons to carry the heat from the center of the head in order to prevent pre-ignition. In the Mercedes motor the pistons have a drop forged steel head which includes the piston boss and this head is screwed into a cast iron skirt which has been machined inside to secure uniform wall thickness.
CENSORED
The carburetor used on this 150 horse-power Mercedes motor is precisely of the same type used on the Twin Six motor. It has two venturi throats, in the center of which is placed the gasoline spray nozzle of conventional type, fixed size orifices, immediately above which are placed two panel type throttles with side outlets. An idling or primary nozzle is arranged to discharge above the top of the venturi throat. The carburetor body is of cast aluminum and is water jacketed. It is bolted directly to air passage passing through the top and bottom half of the crank-case which passes down through the oil reservoir. The air before reaching the carburetor proper to some extent has cooled the oil in the crank chamber and has itself been heated to assist in the vaporization. The inlet pipes themselves are copper. All the passages between the venturi throat and the inlet valve have been carefully finished and polished. The only abnormal thing in the design of this motor is the short connecting rod which is considerably less than twice the stroke and would be considered very bad practice in motor car engines. A short connecting rod, however, possesses two very real virtues in that it cuts down height of the motor and the piston passes over the bottom dead center much more slowly than with a long rod.
Fig. 245.—Part Sectional View of 90 Horse-Power Mercedes Engine, Which is Typical of the Design of Larger Sizes.
Other features of the design are a very stiff crank-case, both halves of which are bolted together by means of long through bolts, the crank-shaft main bearings are seated in the lower half of the case instead of in the usual caps and no provision is made for taking up the main bearings. The Mercedes company uses a plunger type of pump having mechanically operated piston valves and it is driven by means of worm gearing.
The overhead cam-shaft construction is extremely light. The cam-shaft is mounted in a nearly cylindrical cast bronze case and is driven by means of bevel gears from the crank-shaft. The vertical bevel gear shaft through which the drive is taken from the crank-shaft to the cam-shaft operates at one and one-half times the crank-shaft speeds and the reduction to the half-time cam-shaft is secured through a pair of bevels. On this vertical shaft there is mounted the water pump and a bevel gear for driving two magnetos. The water pump mounted on this shaft tends to steady the drive and avoid vibration in the gearing.
The cylinder sizes of six-cylinder aviation motors which have been built by Mercedes are
| Bore | Stroke | Horse-power |
| 105 mm. | 140 mm. | 100 |
| 120 mm. | 140 mm. | 135 |
| 140 mm. | 150 mm. | 150 |
| 140 mm. | 160 mm. | 160 |
The largest of these motors has recently had its horsepower increased to 176 at 1450 R. P. M. This general design of motor has been the foundation for a great many other aviation motor designs, some of which have proved very successful but none of which is equal to the original. Among the motors which follow more or less closely the scheme of design and arrangement are the Hall-Scott, the Wisconsin motor, the Renault water-cooled, the Packard, the Christofferson and the Rolls-Royce. Each of these motors show considerable variation in detail. The Rolls-Royce and Renault are the only ones who have used the steel cylinder with the steel jacket. The Wisconsin motor uses an aluminum cylinder with a hardened steel liner and cast-iron valve seats. The Christofferson has somewhat similar design to the Wisconsin with the exception that the valve seats are threaded into the aluminum jacket and the cylinder head has a blank end which is secured to the aluminum casting by means of the valve seat pieces. The Rolls-Royce motors show small differences in details of design in cylinder head and cam-shaft housing from the Mercedes on which it has taken out patents, not only abroad but in this country.
THE BENZ MOTOR
In the Kaiser prize contest for aviation motors a four-cylinder Benz motor of 130 by 180 mm. won first prize, developing 103 B. H. P. at 1290 R. P. M. The fuel consumption was 210 grams per horse-power hour. Total weight of the motor was 153 kilograms. The oil consumption was .02 of a kilogram per horse-power hour. This motor was afterward expanded into a six-cylinder design and three different sizes were built.
The accompanying table gives some of the details of weight, horse-power, etc.
| Motor type | B | FD | FF | |||
| Rated horse-power | 85 | 100 | 150 | |||
| Horse-power at 1250 r.p.m | 88 | 108 | 150 | |||
| Horse-power at 1350 r.p.m | 95 | 115 | 160 | |||
| Bore in millimeters | 106 | 116 | 130 | |||
| Stroke in millimeters | 150 | 160 | 180 | |||
| Offset of the cylinders in millimeters | 18 | 20 | 20 | |||
| Rate of gasoline consumption in grams | 240 | 230 | 225 | |||
| Oil consumption in grams per b.h.p. hour | 10 | 10 | 10 | |||
| Oil capacity in kilograms | 36 | 4 | 4 | 1⁄2 | ||
| Water capacity in litres | 5 | 1⁄2 | 7 | 1⁄2 | 9 | 1⁄2 |
| The weight with water and oil but with two magnetos, fuel feeder and air pump in kilograms | 170 | 200 | 245 | |||
| The weight of motors, including the water pump, two magnetos, double ignition, etc. | 160 | 190 | 230 | |||
| The weight of the exhaust pipe, complete in kilograms | 4 | 4 | .8 | 5 | 1⁄2 | |
| The weight of the propeller hub in kilograms. | 3 | 1⁄2 | 4 | 4 | ||
The Benz cylinder is a simple, straightforward design and a very reliable construction and not particularly difficult to manufacture. The cylinder is cast of iron without a water jacket but including 45 degrees angle elbows to the valve ports. The cylinders are machined wherever possible and at other points have been hand filed and scraped, after which a jacket, which is pressed in two halves, is gas welded by means of short pipes welded on to the jacket. The bottom and the top of the cylinders become water galleries, and by this means separate water pipes with their attendant weight and complication are eliminated. Rubber rings held in aluminum clamps serve to connect the cylinders together. The whole construction turns out very neat and light. The cylinder walls are 4 mm. or 3⁄16′′ thick and the combustion chamber is of cylindrical pancake form and is 140 mm. or 5.60 inch in diameter. The valve seats are 68 mm. in diameter and the valve port is 62 mm. in diameter.
The passage joining the port is 57 mm. in diameter. In order to insert the valves into the cylinder the valve stem is made with two diameters and the valve has to be cocked to insert it in the guide, which has a bronze bushing at its upper end to compensate for the smaller valve stem diameter. The valve stem is 14 mm. or 9⁄16′′ in diameter and is reduced at its upper portion to 91⁄2 mm. The valves are operated through a push rod and rocker arm construction, which is 7⁄16′′ and exceedingly light. Rocker arm supports are steel studs with enlarged heads to take a double row ball bearing. A roller is mounted at one end of the rocker arm to impinge on the end of the valve stem, and the rocker arm has an adjustable globe stud at the other end. The push rods are light steel tubes with a wall thickness of 0.75 mm. and have a hardened steel cup at their upper end to engage the rocker arm globe stud and a hardened steel globe at their lower end to socket in the roller plunger.
The Benz cam-shaft has a diameter of 26 mm. and is bored straight through 18 mm. and there is a spiral gear made integrally with the shaft in about the center of its length for driving the oil pump gear. The cam faces are 10 mm. wide. There is also, in addition to the intake and exhaust cams, a set of half compression cams. The shaft is moved longitudinally in its bearings by means of an eccentric to put these cams into action. At the fore end of the shaft is a driving gear flange which is very small in diameter and very thin. The flange is 68 mm. in diameter and 4 mm. thick and is tapped to take 6 mm. bolts. The total length of cam-shaft is 1038 mm., and it becomes a regular gun boring job to drill a hole of this length.
The cam-shaft gear is 140 mm. or 51⁄2 inches outside diameter. It has fifty-four teeth and the gear face is 15 mm. or 19⁄32′′. The flange and web have an average thickness of 4 mm. or 5⁄32′′ and the web is drilled full of holes interposed between the spur gear mounted on the cam-shaft and the cam-shaft gear. There is a gear which serves to drive the magnetos and tachometer, also the air pump. The shaft is made integrally with this gear and has an eccentric portion against which the air pump roll plunger impinges.
The seven-bearing crank-shaft is finished all over in a beautiful manner, and the shaft out of the particular motor we have shows no signs of wear whatever. The crank-pins are 55 mm. in diameter and 69 mm. long. Through both the crank-pin and main bearings there is drilled a 28 mm. hole, and the crank cheeks are plugged with solder. The crank cheeks are also built to convey the lubricant to the crank-pins. At the fore end of the crank cheek there is pressed on a spur driving gear. There is screwed on to the front end of the shaft a piece which forms a bevel water pump driving gear and the starting dog. At the rear end of the shaft very close to the propeller hub mounting there is a double thrust bearing to take the propeller thrust.
Long, shouldered studs are screwed into the top half of the crank-case portion of the case and pass clean through the bottom half of the case. The case is very stiff and well ribbed. The three center bearing diaphragms have double walls. The center one serves as a duct through which water pipe passes, and those on either side of the center form the carburetor intake air passages and are enlarged in section at one side to take the carburetor barrel throttle.
The pistons are of cast iron and carry three concentric rings 1⁄4 inch wide on their upper end, which are pinned at the joint. The top of the piston forms the frustum of the cone and the pistons are 110 mm. in length. The lower portion of the skirt is machined inside and has a wall thickness of 1 mm. Riveted to the piston head is a conical diaphragm which contacts with the piston pin when in place and serves to carry the heat off the center of the piston.
The oil pump assembly comprises a pair of plunger pumps which draw oil from a separate outside pump, and constructed integrally with it is a gear pump which delivers the oil under about 60 pound pressure through a set of copper pipes in the base to the main bearings. The plunger oil pump shows great refinement of detail. A worm wheel and two eccentrics are machined up out of one piece and serve to operate the plungers.
Fig. 246.—Part Sectional Side View and Sectional End View of Benz 160 Horse-Power Aviation Engine.
Some interesting details of the 160 horse-power Benz motor, which is shown at [Fig. 246], are reproduced from the “Aerial Age Weekly,” and show how carefully the design has been considered.
- Maximum horse-power, 167.5 B. H. P.
- Speed at maximum horse-power, 1,500 R. P. M.
- Piston speed at maximum horse-power, 1,770 ft. per minute.
- Normal horse-power, 160 B. H. P.
- Speed at normal horse-power, 1,400 R. P. M.
- Piston speed at normal horse-power, 1,656 ft. per minute.
- Brake mean pressure at maximum horse-power, 101.2 pound per square inch.
- Brake mean pressure at normal horse-power, 103.4 pound per square inch.
- Specific power cubic inch swept volume per B. H. P., 5.46 cubic inch; 160 B. H. P.
- Weight of piston, complete with gudgeon pin, rings, etc., 5.0 pound.
- Weight of connecting rod, complete with bearings, 4.99 pound; 1.8 pound reciprocating.
- Weight of reciprocating parts per cylinder, 6.8 pound.
- Weight of reciprocating parts per square inch of piston area, 0.33 pound.
- Outside diameter of inlet valve, 68 mm.; 2.68 inches.
- Diameter of inlet valve port (d), 61.5 mm.; 2.42 inches.
- Maximum lift of inlet valve (h), 11 mm.; 0.443 inch.
- Area of inlet valve opening (π d h), 21.25 square cm.; 3.29 square inches.
- Inlet valve opens, degrees on crank, top dead center.
- Inlet valve closes, degrees on crank, 60° late; 35 mm. late.
- Outside diameter of exhaust valve, 68 mm.; 2.68 inches.
- Diameter of exhaust valve port (d), 61.5 mm.; 2.42 inches.
- Maximum lift of exhaust valve (h) 11 mm.; 0.433 inch.
- Area of exhaust valve opening (π d h), 21.25 square cm.; 3.29 square inches.
- Exhaust valve opens, degrees on crank, 60° early; 35 mm. early.
- Exhaust valve closes, degrees on crank, 161⁄2° late; 5 mm. late.
- Length of connecting rod between centers, 314 mm.; 12.36 inches.
- Ratio connecting rod to crank throw, 3.49:1.
- Diameter of crank-shaft, 55 mm. outside, 2.165 inches; 28 mm. inside, 1.102 inches.
- Diameter of crank-pin, 55 mm. outside, 2.165 inches; 28 mm. inside, 1.102 inches.
- Diameter of gudgeon pin, 30 mm. outside, 1.181 inches; 19 mm. inside, 0.708 inch.
- Diameter of cam-shaft, 26 mm. outside, 1.023 inches; 18 mm. inside, 0.708 inch.
- Number of crank-shaft bearings, 7.
- Projected area of crank-pin bearings, 36.85 square cm.; 5.72 square inches.
- Projected area of gudgeon pin bearings, 22.20 square cm.; 3.44 square inches.
- Firing sequence, 1, 5, 3, 6, 2, 4.
- Type of magnetos, ZH6 Bosch.
- Direction of rotation of magneto from driving end, one clock, one anti-clock.
- Magneto timing, full advance, 30° early (16 mm. early).
- Type of carburetors (2) Benz design.
- Fuel consumption per hour, normal horse-power, 0.57 pint.
- Normal speed of propeller, engine speed, 1,400 R. P. M.
AUSTRO-DAIMLER ENGINE
One of the first very successful European flying engines which was developed in Europe is the Austro-Daimler, which is shown in [end section] in a preceding chapter. The first of these motors had four-cylinders, 120 by 140 millimeters, bore and stroke, with cast iron cylinders, overhead valves operated by means of a single rocker arm, controlled by two cams and the valves were closed by a single leaf spring which oscillates with the rocker arm. The cylinders are cast singly and have either copper or steel jackets applied to them. The four-cylinder design was afterwards expanded to the six-cylinder design and still later a six-cylinder motor of 130 by 175 millimeters was developed. This motor uses an offset crank-shaft, as does the Benz motor, and the effect of offset has been discussed earlier on in this treatise. The Benz motor also uses an offset cam-shaft which improves the valve operation and changes the valve lift diagram. The lubrication also is different than any other aviation motor, since individual high pressure metering pumps are used to deliver fresh oil only to the bearings and cylinders, as was the custom in automobile practice some ten years ago.
SUNBEAM AVIATION ENGINES
These very successful engines have been developed by Louis Coatalen. At the opening of the war the largest sized Coatalen motor was 225 horse-power and was of the L-head type having a single cam-shaft for operating valves and was an evolution from the twelve-cylinder racing car which the Sunbeam Company had previously built. Since 1914 the Sunbeam Company have produced engines of six-, eight-, twelve- and eighteen-cylinders from 150 to 500 horse-power with both iron and aluminum cylinders. For the last two years all the motors have had overhead cam-shafts with a separate shaft for operating the intake and exhaust valves. Cam-shafts are connected through to the crank-shaft by means of a train of spur gears, all of which are mounted on two double row ball bearings. In the twin six, 350 horse-power engine, operating at 2100 R. P. M., requires about 4 horse-power to operate the cam-shafts. This motor gives 362 horsepower at 2100 revolutions and has a fuel consumption of 51⁄100 of a pint per brake horse-power hour. The cylinders are 110 by 160 millimeters. The same design has been expanded into an eighteen-cylinder which gives 525 horsepower at 2100 turns. There has also been developed a very successful eight-cylinder motor rated at 2220 horsepower which has a bore and stroke of 120 by 130 millimeters, weight 450 pounds. This motor is an aluminum block construction with steel sleeves inserted. Three valves are operated, one for the inlet and two for the exhaust. One cam-shaft operates the three valves.
Fig. 247.—At Top, the Sunbeam Overhead Valve 170 Horse-Power Six-Cylinder Engine. Below, Side View of Sunbeam 350 Horse-Power Twelve-Cylinder Vee Engine.
The modern Sunbeam engines operate with a mean effective pressure of 135 pounds with a compression ratio of 6 to 1 sea level. The connecting rods are of the articulated type as in the Renault motor and are very short. The weight of these motors turns out at 2.6 pounds per brake horse-power, and they are able to go through a 100 hour test without any trouble of any kind. The lubricating system comprises a dry base and oil pump for drawing the oil off from the base, whence it is delivered to the filter and cooling system. It then is pumped by a separate high pressure gear pump through the entire motor. In these larger European motors, castor-oil is used largely for lubrication. It is said that without the use of castor-oil it is impossible to hold full power for five hours. Coatalen favors aluminum cylinders rather than cast iron. The series of views in [Figs. 247] to [250] inclusive, illustrates the vertical, narrow type of engine; the V-form; and the broad arrow type wherein three rows, each of six-cylinders, are set on a common crank-case. In this water-cooled series the gasoline and oil consumption are notably low, as is the weight per horse-power.
Fig. 248.—Side View of Eighteen-Cylinder Sunbeam Coatalen Aircraft Engine Rated at 475 B.H.P.
Fig. 249.—Sunbeam Eighteen-Cylinder Motor, Viewed from Pump and Magneto End.
In the eighteen-cylinder overhead valve Sunbeam-Coatalen aircraft engine of 475 brake horse-power, there are no fewer than half a dozen magnetos. Each magneto is inclosed. Two sparks are furnished to each cylinder from independent magnetos. On this engine there are also no fewer than six carburetors. Shortness of crank-shaft, and therefore of engine length, and absence of vibration are achieved by the linking of the connecting-rods. Those concerned with three-cylinders in the broad arrow formation work on one crank-pin, the outer rods being linked to the central master one. In consequence of this arrangement, the piston travel in the case of the central row of cylinders is 160 mm., while the stroke of the pistons of the cylinders set on either side is in each case 168 mm. Inasmuch as each set of six-cylinders is completely balanced in itself, this difference in stroke does not affect the balance of the engine as a whole. The duplicate ignition scheme also applies to the twelve-cylinder 350 brake horse-power Sunbeam-Coatalen overhead valve aircraft engine type. It is distinguishable, incidentally, by the passage formed through the center of each induction pipe for the sparking plug in the center cylinder of each block of three. In this, as in the eighteen-cylinder and the six-cylinder types, there are two cam-shafts for each set of cylinders. These cam-shafts are lubricated by low pressure and are operated through a train of inclosed spur wheels at the magneto end of the machine. The six-cylinder, 170 brake horse-power vertical type employs the same general principles, including the detail that each carburetor serves gas to a group of three-cylinders only. It will be observed that this engine presents notably little head resistance, being suitable for multi-engined aircraft.
Fig. 250.—Propeller End of Sunbeam Eighteen-Cylinder 475 B.H.P. Aviation Engine.
INDICATING METERS FOR AUXILIARY SYSTEMS
Fig. 251.—View of Airplane Cowl Board, Showing the Various Navigating and Indicating Instruments to Aid the Aviator in Flight.
The proper functioning of the power plant and the various groups comprising it may be readily ascertained at any time by the pilot because various indicating meters and pressure gauges are provided which are located on a dash or cowl board in front of the aviator, as shown at [Fig. 251]. The speed indicator corresponds to the speedometer of an automobile and gives an indication of the speed the airplane is making, which taken in conjunction with the clock will make it possible to determine the distance covered at a flight. The altimeter, which is an aneroid barometer, outlines with fair accuracy the height above the ground at which a plane is flying. These instruments are furnished to enable the aviator to navigate the airplane when in the air, and if the machine is to be used for cross-country flying, they may be supplemented by a compass and a drift set. It will be evident that these are purely navigating instruments and only indicate the motor condition in an indirect manner. The best way of keeping track of the motor action is to watch the tachometer or revolution counter which is driven from the engine by a flexible shaft. This indicates directly the number of revolutions the engine is making per minute and, of course, any slowing up of the engine in normal flights indicates that something is not functioning as it should. The tachometer operates on the same principle as the speed indicating device or speedometer used in automobiles except that the dial is calibrated to show revolutions per minute instead of miles per hour. At the extreme right of the dash at [Fig. 251] the spark advance and throttle control levers are placed. These, of course, regulate the motor speed just as they do in an automobile. Next to the engine speed regulating levers is placed a push button cut-out switch to cut out the ignition and stop the motor. Three pressure gauges are placed in a line. The one at the extreme right indicates the pressure of air on the fuel when a pressure feed system is used. The middle one shows oil pressure, while that nearest the center of the dash board is employed to show the air pressure available in the air starting system. It will be evident that the character of the indicating instruments will vary with the design of the airplane. If it was provided with an electrical starter instead of an air system electrical indicating instruments would have to be provided.
COMPRESSED AIR-STARTING SYSTEMS
Two forms of air-starting systems are in general use, one in which the crank-shaft is turned by means of an air motor, the other class where compressed air is admitted to the cylinders proper and the motor turned over because of the air pressure acting on the engine pistons. A system known as the “Never-Miss” utilizes a small double-cylinder air pump is driven from the engine by means of suitable gearing and supplies air to a substantial container located at some convenient point in the fuselage. The air is piped from the container to a dash-control valve and from this member to a peculiar form of air motor mounted near the crank-shaft. The air motor consists of a piston to which a rack is fastened which engages a gear mounted on the crank shaft provided with some form of ratchet clutch to permit it to revolve only in one direction, and then only when the gear is turning faster than the engine crank-shaft.
The method of operation is extremely simple, the dash-control valve admitting air from the supply tank to the top of the pump cylinder. When in the position shown in cut the air pressure will force the piston and rack down and set the engine in motion. A variety of air motors are used and in some the pump and motor may be the same device, means being provided to change the pump to an air motor when the engine is to be turned over.
The “Christensen” air starting system is shown at [Figs. 252] and [253]. An air pump is driven by the engine, and this supplies air to an air reservoir or container attached to the fuselage. This container communicates with the top of an air distributor when a suitable control valve is open. An air pressure gauge is provided to enable one to ascertain the air pressure available. The top of each cylinder is provided with a check valve, through which air can flow only in one direction, i.e., from the tank to the interior of the cylinder. Under explosive pressure these check valves close. The function of the distributor is practically the same as that of an ignition timer, its purpose being to distribute the air to the cylinders of the engine only in the proper firing order. All the while that the engine is running and the car is in motion the air pump is functioning, unless thrown out of action by an easily manipulated automatic control. When it is desired to start the engine a starting valve is opened which permits the air to flow to the top of the distributor, and then through a pipe to the check valve on top of the cylinder about to explode. As the air is going through under considerable pressure it will move the piston down just as the explosion would, and start the engine rotating. The inside of the distributor rotates and directs a charge of air to the cylinder next to fire. In this way the engine is given a number of revolutions, and finally a charge of gas will be ignited and the engine start off on its cycle of operation. To make starting positive and easier some gasoline is injected in with the air so an inflammable mixture is present in the cylinders instead of air only. This ignites easily and the engine starts off sooner than would otherwise be the case. The air pressure required varies from 125 to 250 pounds per square inch, depending upon the size and type of the engine to be set in motion.
Fig. 252.—Parts of Christensen Air Starting System Shown at A, and Application of Piping and Check Valves to Cylinders of Thomas-Morse Aeromotor Outlined at B.
Fig. 253.—Diagrams Showing Installation of Air Starting System on Thomas-Morse Aviation Motor.
ELECTRIC STARTING SYSTEMS
Starters utilizing electric motors to turn over the engine have been recently developed, and when properly made and maintained in an efficient condition they answer all the requirements of an ideal starting device. The capacity is very high, as the motor may draw current from a storage battery and keep the engine turning over for considerable time on a charge. The objection against their use is that it requires considerable complicated and costly apparatus which is difficult to understand and which requires the services of an expert electrician to repair should it get out of order, though if battery ignition is used the generator takes the place of the usual ignition magneto.
In the Delco system the electric current is generated by a combined motor-generator permanently geared to the engine. When the motor is running it turns the armature and the motor generator is acting as a dynamo, only supplying current to a storage battery. On account of the varying speeds of the generator, which are due to the fluctuation in engine speed, some form of automatic switch which will disconnect the generator from the battery at such times that the motor speed is not sufficiently high to generate a current stronger than that delivered by the battery is needed. These automatic switches are the only delicate part of the entire apparatus, and while they require very delicate adjustment they seem to perform very satisfactorily in practice.
When it is desired to start the engine an electrical connection is established between the storage battery and the motor-generator unit, and this acts as a motor and turns the engine over by suitable gearing which engages the gear teeth cut into a special gear or disc attached to the engine crank-shaft. When the motor-generator furnishes current for ignition as well as for starting the motor, the fact that the current can be used for this work as well as starting justifies to a certain extent the rather complicated mechanism which forms a complete starting and ignition system, and which may also be used for lighting if necessary in night flying.
An electric generator and motor do not complete a self-starting system, because some reservoir or container for electric current must be provided. The current from the generator is usually stored in a storage battery from which it can be made to return to the motor or to the same armature that produced it. The fundamental units of a self-starting system, therefore, are a generator to produce the electricity, a storage battery to serve as a reservoir, and an electric motor to rotate the motor crank-shaft. Generators are usually driven by enclosed gearing, though silent chains are used where the center distance between the motor shaft and generator shaft is too great for the gears. An electric starter may be directly connected to the gasoline engine, as is the case where the combined motor-generator replaces the fly-wheel in an automobile engine. The motor may also drive the engine by means of a silent chain or by direct gear reduction.
Every electric starter must use a switch of some kind for starting purposes and most systems include an output regulator and a reverse current cut-out. The output regulator is a simple device that regulates the strength of the generator current that is supplied the storage battery. A reverse current cut-out is a form of check valve that prevents the storage battery from discharging through the generator. Brief mention is made of electric starting because such systems will undoubtedly be incorporated in some future airplane designs. Battery ignition is already being experimented with.
BATTERY IGNITION SYSTEM PARTS
A battery ignition system in its simplest form consists of a current producer, usually a set of dry cells or a storage battery, an induction coil to transform the low tension current to one having sufficient strength to jump the air gap at the spark-plug, an igniter member placed in the combustion chamber and a timer or mechanical switch operated by the engine so that the circuit will be closed only when it is desired to have a spark take place in the cylinders. Battery ignition systems may be of two forms, those in which the battery current is stepped up or intensified to enable it to jump an air gap between the points of the spark plug, these being called “high tension” systems and the low tension form (never used on airplane motors) in which the battery current is not intensified to a great degree and a spark produced in the cylinder by the action of a mechanical circuit breaker in the combustion chamber. The low tension system is the simplest electrically but the more complex mechanically. The high tension system has the fewest moving parts but numerous electrical devices. At the present time all airplane engines use high tension ignition systems, the magneto being the most popular at the present time. The current distribution and timing devices used with modern battery systems are practically the same as similar parts of a magneto.
INDEX
| A | |
| PAGE | |
| Action of Four-cycle Engine | [38] |
| Action of Le Rhone Rotary Engine | [503] |
| Action of Two-cycle Engine | [41] |
| Action of Vacuum Feed System | [119] |
| Actual Duration of Different Functions | [93] |
| Actual Heat Efficiency | [62] |
| Adiabatic Diagram | [51] |
| Adiabatic Law | [50] |
| Adjustment of Bearings | [449] |
| Adjustment of Carburetors | [151] |
| Aerial Motors, Must be Light | [20] |
| Aerial Motors, Operating Conditions of | [19] |
| Aerial Motors, Requirements of | [19] |
| Aeromarine Six-cylinder Engine | [527] |
| Aeronautics, Division in Branches | [18] |
| Aerostatics | [18] |
| Air-cooled Engine Design | [229] |
| Air-cooling Advantages | [231] |
| Air-cooling, Direct Method | [228] |
| Air-cooling Disadvantages | [231] |
| Air-cooling Systems | [223] |
| Aircraft, Heavier Than Air | [17] |
| Aircraft, Lighter Than Air | [18] |
| Aircraft Types, Brief Consideration of | [17] |
| Air Needed to Burn Gasoline | [113] |
| Airplane Engine, Power Needed | [21] |
| Airplane Engines, Overhauling | [412] |
| Airplane Engine, How to Time | [269] |
| Airplane Engine Lubrication | [209] |
| Airplane, How Supported | [21] |
| Airplane Motors, German | [543] |
| Airplane Motor Types | [20] |
| Airplane Motors, Weight of | [21] |
| Airplane Power Plant Installation | [324] |
| Airplane Types | [18] |
| Airplanes, Horse-power Used in | [26] |
| Air Pressure Diminution, With Altitude | [144] |
| Altitude, How it Affects Mixture | [153] |
| Aluminum, Use in Pistons | [297] |
| American Aviation Engines, Statistics | [546] |
| Anzani Radial Engine Installation | [344] |
| Anzani Six-cylinder Star Engine | [465] |
| Anzani Six-cylinder Water-cooled Engine | [459] |
| Anzani Ten- and Twenty-cylinder Engines | [468] |
| Anzani Three-cylinder Engine | [459] |
| Anzani Three-cylinder Y Type | [462] |
| Argus Engine Construction | [545] |
| Armature Windings | [168] |
| Atmospheric Conditions, Compensating For | [143] |
| Austro-Daimler Engine | [557] |
| Aviatics | [18] |
| Aviation Engine, Aeromarine | [527] |
| Aviation Engine, Anzani Six-cylinder Star | [465] |
| Aviation Engine, Canton and Unné | [469] |
| Aviation Engine Cooling | [219] |
| Aviation Engine, Curtiss | [519] |
| Aviation Engine Cylinders | [233] |
| Aviation Engine, Early Gnome | [472] |
| Aviation Engine, German Gnome Type | [495] |
| Aviation Engine, Gnome Monosoupape | [486] |
| Aviation Engine, How To Dismantle | [415] |
| Aviation Engine, How to Start | [460] |
| Aviation Engine, Le Rhone Rotary | [495] |
| Aviation Engine Oiling | [218] |
| Aviation Engine Parts, Functions of | [82] |
| Aviation Engine, Renault Air-cooled | [507] |
| Aviation Engine, Stand for Supporting | [414] |
| Aviation Engine, Sturtevant | [515] |
| Aviation Engine, Thomas-Morse | [521] |
| Aviation Engine Types | [457] |
| Aviation Engine, Wisconsin | [531] |
| Aviation Engines, Anzani Six-cylinder Water-cooled | [459] |
| Aviation Engines, Anzani Ten- and Twenty-cylinder | [468] |
| Aviation Engines, Anzani Three-cylinder | [459] |
| Aviation Engines, Anzani Y Type | [462] |
| Aviation Engines, Argus | [545] |
| Aviation Engines, Austro-Daimler | [557] |
| Aviation Engines, Benz | [551] |
| Aviation Engines, Four- and Six-cylinder | [88] |
| Aviation Engines, German | [543] |
| Aviation Engines, Hall-Scott | [539] |
| Aviation Engines, Hispano-Suiza | [512] |
| Aviation Engines, Mercedes | [543] |
| Aviation Engines, Overhauling | [412] |
| Aviation Engines, Principal Parts of | [80] |
| Aviation Engines, Starting Systems For | [567] |
| Aviation Engines, Sunbeam | [558] |
| B | |
| Balanced Crank-shafts | [318] |
| Ball-bearing Crank-shafts | [319] |
| Battery Ignition Systems | [571] |
| Baverey Compound Nozzle | [137] |
| Bearings, Adjustment of | [449] |
| Bearing Alignment | [453] |
| Bearing Brasses, Fitting | [450] |
| Bearing Parallelism, Testing | [453] |
| Bearing Scrapers and Their Use | [446] |
| Benz Aviation Engines | [551] |
| Benz Engine Statistics | [551] |
| Berling Magneto | [174] |
| Berling Magneto, Adjustment of | [180] |
| Berling Magneto Care | [180] |
| Berling Magneto Circuits | [176] |
| Berling Magneto, Setting | [178] |
| Block Castings | [234] |
| Blowing Back | [269] |
| Bolts, Screwing Down | [452] |
| Bore and Stroke Ratio | [240] |
| Boyle’s Law | [49] |
| Brayton Engine | [48] |
| Breaker Box, Adjustment of | [180] |
| Breast and Hand Drills | [387] |
| Burning Out Carbon Deposits | [421] |
| Bushings, Camshaft, Wear in | [456] |
| C | |
| Calipers, Inside and Outside | [398] |
| Cam Followers, Types of | [260] |
| Cams for Valve Actuation | [259] |
| Cam-shaft Bushings | [456] |
| Cam-shaft Design | [313] |
| Cam-shaft Drive Methods | [261] |
| Cam-shaft Testing | [451] |
| Cam-shafts and Timing Gears | [456] |
| Canton and Unné Engine | [469] |
| Carbon, Burning out with Oxygen | [421] |
| Carbon Deposits, Cause of | [418] |
| Carbon Removal | [419] |
| Carbon Scrapers, How Used | [420] |
| Carburetion Principles | [112] |
| Carburetion System Troubles | [355] |
| Carburetor, Claudel | [127] |
| Carburetor, Compound Nozzle Zenith | [135] |
| Carburetor, Concentric Float and Jet Type | [125] |
| Carburetor, Duplex Zenith | [138] |
| Carburetor, Duplex Zenith, Trouble in | [357] |
| Carburetor Installation, In Airplanes | [148] |
| Carburetor, Le Rhone | [501] |
| Carburetor, Master Multiple Jet | [133] |
| Carburetor, Schebler | [125] |
| Carburetor Troubles, How to Locate | [354] |
| Carburetor, Two Stage | [131] |
| Carburetor, What it Should Do | [114] |
| Carburetors, Float Feed | [122] |
| Carburetors, Multiple Nozzle | [130] |
| Carburetors, Notes on Adjustment | [151] |
| Carburetors, Reversing Position of | [149] |
| Carburetors, Spraying | [120] |
| Care of Dixie Magneto | [188] |
| Castor Oil, for Cylinder Lubrication | [205] |
| Castor Oil, Why Used In Gnome Engines | [211] |
| Center Gauge | [403] |
| Chisels, Forms of | [384] |
| Christensen Air Starting System | [567] |
| Circuits, Magnetic | [161] |
| Classification of Engines | [458] |
| Claudel Carburetor | [127] |
| Cleaning Distributor | [180] |
| Clearances Between Valve Stem and Actuators | [261] |
| Combustion Chamber Design | [239] |
| Combustion Chambers, Spherical | [76] |
| Common Tools, Outfit of | [378] |
| Comparing Two-cycle and Four-cycle Types | [44] |
| Compound Cam Followers | [260] |
| Compound Piston Rings | [301] |
| Compressed Air Starting System | [565] |
| Compression, Factors Limiting | [69] |
| Compression, in Explosive Motors, Value of | [68] |
| Compression Pressures, Chart for | [72] |
| Compression Temperature | [71] |
| Computations for Horse-power Needed | [25] |
| Computations for Temperature | [52] |
| Concentric Piston Ring | [299] |
| Concentric Valves | [255] |
| Connecting Rod Alignment, Testing | [454] |
| Connecting Rod, Conventional | [308] |
| Connecting Rod Forms | [305] |
| Connecting Rod, Gnome Engine | [305] |
| Connecting Rods, Fitting | [449] |
| Connecting Rods for Vee Engines | [310] |
| Connecting Rods, Le Rhone | [498] |
| Connecting Rods, Master | [310] |
| Constant Level Splash System | [215] |
| Construction of Dixie Magneto | [186] |
| Construction of Pistons | [288] |
| Conversion of Heat to Power | [58] |
| Cooling by Air | [223] |
| Cooling by Positive Water Circulation | [224] |
| Cooling, Heat Loss in | [66] |
| Cooling System Defects | [358] |
| Cooling Systems Used | [223] |
| Cooling Systems, Why Needed | [219] |
| Cotter Pin Pliers | [384] |
| Crank-case, Conventional | [320] |
| Crank-case Forms | [320] |
| Crank-case, Gnome | [323] |
| Crank-shaft, Built Up | [315] |
| Crank-shaft Construction | [315] |
| Crank-shaft Design | [315] |
| Crank-shaft Equalizer | [449] |
| Crank-shaft Form | [315] |
| Crank-shaft, Gnome Engine | [483] |
| Crank-shafts, Balanced | [318] |
| Crank-shafts, Ball Bearing | [319] |
| Cross Level | [403] |
| Crude Petroleum, Distillates of | [111] |
| Curtiss Aviation Engines | [519] |
| Curtiss Engine Installation | [328] |
| Curtiss Engine Repairing Tools | [408] |
| Cutting Oil Grooves | [448] |
| Cylinder Blocks, Advantages of | [237] |
| Cylinder Block, Duesenberg | [235] |
| Cylinder Castings, Individual | [234] |
| Cylinder Construction | [233] |
| Cylinder Faults and Correction | [416] |
| Cylinder Form and Crank-shaft Design | [238] |
| Cylinder Head Packings | [417] |
| Cylinder Head, Removable | [239] |
| Cylinder, I Head Form | [248] |
| Cylinder, L Head Form | [248] |
| Cylinder Oils | [206] |
| Cylinder Placing | [20] |
| Cylinder Placing in V Motor | [99] |
| Cylinder Retention, Gnome | [475] |
| Cylinder, T Head Form | [248] |
| Cylinders, Cast in Blocks | [235] |
| Cylinders, Odd Number in Rotary Engines | [482] |
| Cylinders, Repairing Scored | [423] |
| Cylinders, Valve Location in | [245] |
| D | |
| Defects in Cylinders | [417] |
| Defects in Dry Battery | [373] |
| Defects in Fuel System | [354] |
| Defects in Induction Coil | [373] |
| Defects in Magneto | [372] |
| Defects in Storage Battery | [372] |
| Defects in Timer | [373] |
| Defects in Wiring and Remedies | [373] |
| Die Holder | [394] |
| Dies for Thread Cutting | [395] |
| Diesel Motor Cards | [67] |
| Diesel System | [144] |
| Direct Air Cooling | [228] |
| Dirigible Balloons | [18] |
| Dismantling Airplane Engine | [415] |
| Distillates of Crude Petroleum | [111] |
| Division of Circle in Degrees | [268] |
| Dixie Ignition Magneto | [184] |
| Dixie Magneto, Care of | [188] |
| Draining Oil From Crank-case | [214] |
| Drilling Machines | [386] |
| Drills, Types and Use | [388] |
| Driving Cam-shaft, Methods of | [262] |
| Dry Cell Battery, Defects in | [373] |
| Duesenberg Sixteen Valve Engine | [525] |
| Duesenberg Valve Action | [255] |
| Duplex Zenith Carburetor | [138] |
| E | |
| Early Gnome Motor, Construction of | [472] |
| Early Ignition Systems | [155] |
| Early Types of Gas Engine | [28] |
| Early Vaporizer Forms | [120] |
| Eccentric Piston Ring | [299] |
| Economy, Factors Governing | [64] |
| Efficiency, Actual Heat | [62] |
| Efficiency, Maximum Theoretical | [61] |
| Efficiency, Mechanical | [62] |
| Efficiency of Internal Combustion Engine | [60] |
| Efficiency, Various Measures of | [61] |
| Eight-cylinder Engine | [95] |
| Eight-cylinder Timing Diagram | [276] |
| Electricity and Magnetism, Relation of | [162] |
| Electrical Ignition Best | [156] |
| Electric Starting Systems | [569] |
| Engine, Advantages of V Type | [95] |
| Engine Base Construction | [319] |
| Engine Bearings, Adjusting | [443] |
| Engine Bearings, Refitting | [442] |
| Engine Bed Timbers, Standard | [330] |
| Engine, Four-cycle, Action of | [38] |
| Engine, Four-cycle, Piston Movements in | [40] |
| Engine Functions, Duration of | [93] |
| Engine Ignition, Locating Troubles | [353] |
| Engine Installation, Gnome | [344] |
| Engine Installation, Anzani Radial | [344] |
| Engine Installation, Hall-Scott | [332] |
| Engine Installation, Rotary | [342] |
| Engine Operation, Sequence of | [84] |
| Engine Parts and Functions | [80] |
| Engine Starts Hard, Ignition Troubles Causing | [369] |
| Engine Stoppage, Causes of | [347] |
| Engine Temperatures | [221] |
| Engine Trouble Charts | [369] |
| Engine Troubles, Cooling | [358] |
| Engine Troubles, Hints For Locating | [345] |
| Engine Troubles, Ignition | [353] |
| Engine Troubles, Noisy Operation | [359] |
| Engine Troubles, Oiling | [357] |
| Engine Troubles Summarized | [350] |
| Engine, Two-cycle, Action of | [41] |
| Engines, Classification of | [458] |
| Engines, Cylinder Arrangement | [31]-[32] |
| Engines, Eight-cylinder V | [95] |
| Engines, Four-cylinder Forms | [88] |
| Engines, Graphic Comparison of | [33]-[34]-[35] |
| Engines, Internal Combustion, Types of | [30] |
| Engines, Multiple Cylinder, Power Delivery in | [91] |
| Engines, Multiple Cylinder, Why Best | [83] |
| Engines, Rotary Cylinder | [107] |
| Engines, Six-cylinder Forms | [88] |
| Engines, Twelve-cylinder | [96] |
| Equalizer, Crank-shaft | [449] |
| Exhaust Closing | [270] |
| Exhaust Valve Design, Early Gnome | [475] |
| Exhaust Valve Opening | [270] |
| Explosive Gases, Mixtures of | [56] |
| Explosive Motors, Inefficiency in | [74] |
| Explosive Motors, Why Best | [27] |
| F | |
| Factors Governing Economy | [64] |
| Factors Limiting Compression | [70] |
| Faults in Ignition | [352] |
| Figuring Horse-power Needed | [21] |
| Files, Use and Care of | [383] |
| First Law of Gases | [49] |
| Fitting Bearings By Scraping | [447] |
| Fitting Brasses | [450] |
| Fitting Connecting Rods | [449] |
| Fitting Main Bearings | [448] |
| Fitting Piston Rings | [439] |
| Float Feed Carburetor Development | [124] |
| Float Feed Carburetors | [122] |
| Force Feed Oiling System | [218] |
| Forked Connecting Rods | [310] |
| Four-cycle Engine, Action of | [38] |
| Four-cycle Engine, Why Best | [45] |
| Fourteen-cylinder Engine | [474] |
| Four Valves Per Cylinder | [284] |
| Friction, Definition of | [302] |
| Fuel Feed By Gravity | [116] |
| Fuel Feed by Vacuum Tank | [117] |
| Fuel Storage and Supply | [116] |
| Fuel Strainers, Types of | [141] |
| Fuel Strainers, Utility of | [140] |
| Fuel System Faults | [354] |
| Fuel System Installation, Hall-Scott | [336] |
| Fuel System, Gnome | [490] |
| Fuel Utilization Chart | [62] |
| G | |
| Gas Engine, Beau de Rocha’s Principles | [59] |
| Gas Engine Development | [28] |
| Gas Engine, Early Forms of | [48] |
| Gas Engine, Inventors of | [29] |
| Gas Engine, Theory of | [47] |
| Gases, Compression of | [49] |
| Gases, First Law of | [49] |
| Gases, Second Law of | [50] |
| Gaskets, How to Use | [452] |
| Gasoline, Air Needed to Burn | [113] |
| Gas Engines, Parts of | [80] |
| Gas Vacuum Engine, Brown’s | [28] |
| German Airplane Motors | [543] |
| German Gnome Type Engine | [495] |
| Gnome Aviation Engine, Early Form | [472] |
| Gnome Crank-shaft | [483] |
| Gnome Cylinder, Machining | [489] |
| Gnome Cylinder Retention | [475] |
| Gnome Engine, Fuel, Lubrication and Ignition | [490] |
| Gnome Engine, German Type | [495] |
| Gnome Engine Installation | [344] |
| Gnome Firing Order | [482] |
| Gnome Fourteen-cylinder, Engine | [474] |
| Gnome Fourteen-cylinder Engine Details | [480] |
| Gnome Monosoupape, How to Time | [278] |
| Gnome Monosoupape Type Engine | [486] |
| Graphic Comparison of Engine Types | [33]-[34]-[35] |
| Graphic Comparison, Two- and Four-cycle | [46] |
| Gravity Feed System | [116] |
| Grinding Valves | [429] |
| H | |
| Hall-Scott Aviation Engines | [539] |
| Hall-Scott Engine Installation | [332] |
| Hall-Scott Engine, Preparations For Starting | [341] |
| Hall-Scott Engine Tools | [410] |
| Hall-Scott Lubrication System | [211] |
| Hall-Scott Statistic Sheet | [544] |
| Heat and Its Work | [54] |
| Heat in Gas Engine Cylinder | [69] |
| Heat Given to Cooling Water | [78] |
| Heat Loss, Causes of | [74] |
| Heat Loss in Airplane Engine | [221] |
| Heat Loss in Wall Cooling | [65] |
| High Altitude, How it Affects Power | [144] |
| High Tension Magneto | [172] |
| Hints For Locating Engine Troubles | [345] |
| Hints for Starting Engine | [361] |
| Hispano-Suiza Model A Engine | [512] |
| Horse-power Needed in Airplane | [21] |
| Horse-power Needed, How Figured | [22] |
| How An Engine is Timed | [277] |
| I | |
| Ignition, Electric | [156] |
| Ignition, Elements of | [157] |
| Ignition of Gnome Engine | [490] |
| Ignition System, Battery | [571] |
| Ignition Systems, Early | [155] |
| Ignition System Faults | [352] |
| Ignition, Time of | [273] |
| Ignition, Two Spark | [196] |
| I Head Cylinders | [248] |
| Improvements in Gas Engines | [29] |
| Indicating Meters, Engine Speed | [563] |
| Indicating Meters, Oil and Air Pressure | [563] |
| Indicator Cards, How To Read | [66] |
| Indicator Cards, Value of | [66] |
| Individual Cylinder Castings | [234] |
| Induction Coil, Defects in | [373] |
| Inefficiency, Causes of | [74] |
| Inlet Valve Closing | [272] |
| Inlet Valve Opening | [270] |
| Installation, Airplane Engine | [324] |
| Installation, Curtiss OX-2 Engine | [328] |
| Installation, Hall-Scott Engine | [332] |
| Installation of Rotary Engines | [342] |
| Intake Manifold Construction | [143] |
| Intake Manifold Design | [142] |
| Internal Combustion Engine, Efficiency of | [60], [62] |
| Internal Combustion Engines, Main Types of | [30] |
| Inverted Engine Placing | [325] |
| Isothermal Diagram | [51] |
| Isothermal Law | [48] |
| K | |
| Keeping Oil Out of Combustion Chamber | [303] |
| Knight Sleeve Valves | [266] |
| L | |
| Lag and Lead, Explanation of | [268] |
| Lapping Crank-pins | [445] |
| Lead Given Exhaust Valve | [270] |
| Leak Proof Piston Rings | [301] |
| Lenoir Engine Action | [48] |
| Le Rhone Cams and Valve Actuation | [500] |
| Le Rhone Carburetor | [501] |
| Le Rhone Connecting Rod Assembly, Distinctive | [498] |
| Le Rhone Engine Action | [503] |
| Le Rhone Rotary Engine | [495] |
| L Head Cylinders | [248] |
| Liquid Fuels, Properties of | [110] |
| Locating Carburetor Troubles | [354] |
| Locating Engine Troubles | [350] |
| Locating Ignition Troubles | [353] |
| Locating Oiling Troubles | [357] |
| Location of Magneto Trouble | [181] |
| Losses in Wall Cooling | [65] |
| Lost Power and Overheating, Summary of Troubles Causing | [363] |
| Lubricants, Derivation of | [204] |
| Lubricants, Requirements of | [204] |
| Lubricating System Classification | [208] |
| Lubricating Systems, Selection of | [208] |
| Lubrication By Constant Level Splash System | [215] |
| Lubrication By Dry Crank-case Method | [218] |
| Lubrication By Force Feed Best | [218] |
| Lubrication of Magneto | [180] |
| Lubrication System, Gnome | [490] |
| Lubrication System, Hall-Scott | [211] |
| Lubrication System, Thomas-Morse | [210] |
| Lubrication, Theory of | [202] |
| Lubrication, Why Necessary | [201] |
| M | |
| Magnetic Circuits | [161] |
| Magnetic Influence Defined | [158] |
| Magnetic Lines of Force | [161] |
| Magnetic Substances | [158] |
| Magnetism, Flow Through Armature | [166] |
| Magnetism, Fundamentals of | [157] |
| Magnetism, Relation to Electricity | [162] |
| Magneto, Action of High Tension | [173] |
| Magneto Armature Windings | [168] |
| Magneto, Basic Principles of | [163] |
| Magneto, Berling | [174] |
| Magneto, Defects in | [372] |
| Magneto Distributor, Cleaning | [180] |
| Magneto Ignition Systems | [169] |
| Magneto Ignition Wiring | [179] |
| Magneto Interrupter, Adjustment of | [180] |
| Magneto, Low Voltage | [168] |
| Magneto, Lubrication of | [180] |
| Magneto Maintenance | [180] |
| Magneto, Method of Driving | [175] |
| Magneto Parts and Functions | [167] |
| Magneto, The Dixie | [184] |
| Magneto Timing | [179] |
| Magneto, Timing Dixie | [188] |
| Magneto, Transformer System | [171] |
| Magneto Trouble, Location of | [181] |
| Magneto, True High Tension | [172] |
| Magneto, Two Spark Dual | [177] |
| Magnets, Forms of | [160] |
| Magnets, How Produced | [162] |
| Magnets, Properties of | [159] |
| Main Bearings, Fitting | [448] |
| Manifold, Intake | [143] |
| Master Multiple Jet Carburetor | [133] |
| Master Rod Construction | [310] |
| Maximum Theoretical Efficiency | [61] |
| Meaning of Piston Speed | [241] |
| Measures of Efficiency | [61] |
| Measuring Tools | [397] |
| Mechanical Efficiency | [62] |
| Mercedes Aviation Engine | [543] |
| Metering Pin Carburetor, Stewart | [128] |
| Micrometer Caliper, Beading | [405] |
| Micrometer Calipers, Types and Use | [404] |
| Mixture, Effect of Altitude on | [153] |
| Mixture, Proportions of | [151] |
| Mixture, Starvation of | [149] |
| Monosoupape Gnome Engine | [486] |
| Mother Bod, Gnome Engine | [305] |
| Motor Misfires, Carburetor Faults Causing | [374] |
| Motor Misfires, Ignition Troubles Causing | [370] |
| Motor Races, Carburetor Faults Causing | [374] |
| Motor Starts Hard, Carburetor Faults Causing | [374] |
| Motor Stops In Flight, Carburetor Faults | [374] |
| Motor Stops Without Warning, Ignition Troubles | [370] |
| Multiple Cylinder Engine, Why Best | [83] |
| Multiple Nozzle Vaporizers | [129] |
| Multiple Valve Advantages | [286] |
| N | |
| Noisy Engine Operation, Causes of | [359] |
| Noisy Operation, Carburetor Faults Causing | [374] |
| Noisy Operation, Summary of Troubles Causing | [365] |
| O | |
| Off-set Cylinders, Reason for | [243] |
| Oil Bi-pass, Function of | [213] |
| Oil, Draining From Crank-case | [214] |
| Oil Grooves, Cutting | [448] |
| Oil Pressure in Hall-Scott System | [214] |
| Oil Pressure Relief Bi-pass | [213] |
| Oiling System Defects | [357] |
| Oils for Cylinder Lubrication | [206] |
| Oils for Hall-Scott Engine | [215] |
| Oils for Lubrication | [204] |
| Operating Principles of Engines | [37] |
| Oscillating Piston Pin | [295] |
| Otto Four-cycle Cards | [67] |
| Overhauling Aviation Engines | [412] |
| Overhead Cam-shaft Location | [252] |
| Overheating, Causes of | [359] |
| P | |
| Panhard Concentric Valves | [255] |
| Petroleum, Distillates of | [111] |
| Piston, Differential | [291] |
| Piston Pin Retention | [293] |
| Piston Ring Construction | [298] |
| Piston Ring Joints | [299] |
| Piston Ring Manipulation | [438] |
| Piston Ring Troubles | [437] |
| Piston Rings, Compound | [301] |
| Piston Rings, Concentric | [299] |
| Piston Rings, Eccentric | [299] |
| Piston Rings, Fitting | [439] |
| Piston Rings, Leak Proof | [301] |
| Piston Rings, Replacing | [441] |
| Piston Speed in Airplane Engines | [241] |
| Piston Speed, Meaning of | [241] |
| Piston Troubles and Remedies | [436] |
| Pistons, Aluminum | [296] |
| Pistons, Details of | [288] |
| Pistons for Two-cycle Engines | [289] |
| Positive Valve Systems | [283] |
| Power, Affected by High Altitude | [145] |
| Power Delivery in Multiple Cylinder Engines | [91] |
| Power, How Obtained From Heat | [58] |
| Power Needed in Airplane Engines | [21] |
| Power Used in Airplanes | [26] |
| Precautions in Assembling Parts | [452] |
| Pressure Relief Fitting | [213] |
| Pressures and Temperatures | [63] |
| Principles of Carburetion | [112] |
| Principles of Magneto Action | [163] |
| Properties of Cylinder Oils | [207] |
| Properties of Liquid Fuels | [110] |
| Pump Circulation Systems | [226] |
| Pump Forms | [226] |
| R | |
| Radial Cylinder Arrangement | [103] |
| Reading Indicator Cards | [67] |
| Reamers, Types and Use | [392] |
| Reassembling Parts, Precautions in | [451] |
| Removable Cylinder Head | [239] |
| Renault Air Cooled Engine | [507] |
| Renault Engine Details | [508] |
| Repairing Scored Cylinders | [423] |
| Requisites for Best Power Effect | [59] |
| Reseating and Truing Valves | [426] |
| Resistance, Influence of | [22] |
| Rotary Cylinder Engines | [107] |
| Rotary Engine, Le Rhone | [495] |
| Rotary Engines, Castor Oil for | [211] |
| Rotary Engines, Installing | [342] |
| Rotary Engines, Why Odd Number of Cylinders | [109] |
| Rotary Engines, Why Odd Number of Cylinders Is Used | [482] |
| S | |
| S. A. E. Engine Bed Dimensions | [330] |
| Salmson Nine-cylinder Engine | [470] |
| Scissors Joint Rods | [310] |
| Scored Cylinders, Repairing | [422] |
| Scrapers, Types of Bearing | [446] |
| Scraping Bearings to Fit | [447] |
| Second Law of Gases | [50] |
| Sequence of Engine Operation | [84] |
| Shebler Carburetor | [125] |
| Six-cylinder Timing Diagram | [275] |
| Sixteen Valve Duesenberg Engine | [525] |
| Skipping or Irregular Operation, Causes of | [367] |
| Sliding Sleeve Valves | [266] |
| Spark Plug Air Gaps, Setting | [197] |
| Spark Plug, Design of | [193] |
| Spark Plug, Mica | [194] |
| Spark Plug, Porcelain | [193] |
| Spark Plugs, Defects in | [371] |
| Spark Plugs for Two Spark Ignition | [197] |
| Spark Plug, Special for Airplane Engine | [199] |
| Spark Plug, Standard S. A. E. | [195] |
| Spherical Combustion Chambers | [76] |
| Splash Lubrication | [215] |
| Split Pin Remover | [384] |
| Spraying Carburetors | [120] |
| Springless Valves | [280] |
| Springs, for Valves | [263] |
| Spring Winder | [384] |
| Sprung Cam-shaft, Testing | [451] |
| Stand for Supporting Engine | [414] |
| Starting Engine, Hints for | [361] |
| Starting Hall-Scott Engine | [341] |
| Starting System, Christensen | [567] |
| Starting Systems, Compressed Air | [565] |
| Starting Systems, Electric | [569] |
| Statistics, American Engines | [546], [547] |
| Statistic Sheet, Hall-Scott Engines | [544] |
| Statistics of Benz Engine | [551] |
| Steam Engine, Efficiency of | [59] |
| Steam Engine, Why Not Used | [27] |
| Steel Scale, Machinists’ | [399] |
| Stewart Metering Pin Carburetor | [128] |
| Storage Battery, Defects in | [372] |
| Stroke and Bore Ratio | [240] |
| Sturtevant Model 5A Engine | [515] |
| Summary of Engine Types | [30] |
| Sunbeam Aviation Engines | [588] |
| Sunbeam Eighteen-Cylinder Engine | [561] |
| T | |
| Tap and Die Sets | [397] |
| Taps for Thread Cutting | [394] |
| Tee Head Cylinders | [247] |
| Temperature Computations | [52] |
| Temperatures and Explosive Pressures | [64] |
| Temperatures and Pressures | [63] |
| Temperatures, Operating | [221] |
| Testing Bearing Parallelism | [453] |
| Testing Connecting Rod Alignment | [454] |
| Testing Fit of Bearings | [446] |
| Testing Sprung Cam-shaft | [451] |
| Theory of Gas Engine | [47] |
| Theory of Lubrication | [203] |
| Thermo-syphon Cooling System | [227] |
| Thomas-Morse Aviation Engine | [521] |
| Thomas-Morse Lubrication System | [210] |
| Thread Pitch Gauge | [403] |
| Time of Ignition | [273] |
| Timer, Defects in | [373] |
| Times of Explosion | [56] |
| Timing Dixie Magneto | [188] |
| Timing Gears, Effects of Wear | [456] |
| Timing Magneto | [179] |
| Timing Valves | [267] |
| Tool Outfits, Typical | [408] |
| Tools for Adjusting and Erecting | [378] |
| Tools for Bearing Work | [445] |
| Tools for Curtiss Engines | [408] |
| Tools for Grinding Valves | [430] |
| Tools for Hall-Scott Engines | [410], [411] |
| Tools for Measuring | [397] |
| Tools for Reseating Valves | [426] |
| Trouble in Carburetion System | [355] |
| Trouble, Location of Magneto | [181] |
| Troubles, Engine, How to Locate | [345] |
| Troubles, Ignition | [353] |
| Troubles in Oiling System | [357] |
| True High Tension Magneto | [172] |
| Twelve-Cylinder Engines | [96] |
| Two-and Four-Cycle Types, Comparison of | [44] |
| Two-Cycle Engine Action | [41] |
| Two-Cycle Three-Port Engine | [43] |
| Two-Cycle Two-Port Engine | [42] |
| Two-Spark Ignition | [196] |
| Two-Stage Carburetor | [131] |
| Types of Aircraft | [17] |
| Types of Internal Combustion Engines | [30] |
| V | |
| Vacuum Fuel Feed, Stewart | [119] |
| Value of Compression | [69] |
| Value of Indicator Cards | [66] |
| Valve Actuation, Le Rhone | [500] |
| Valve Design and Construction | [256] |
| Valve-Grinding Processes | [429] |
| Valve-Lifting Cams | [259] |
| Valve-Lifting Plungers | [260] |
| Valve Location Practice | [245] |
| Valve Operating Means | [252] |
| Valve Operating System, Depreciation in | [433] |
| Valve Operation | [258] |
| Valve Removal and Inspection | [424] |
| Valve Seating, How to Test | [432] |
| Valve Springs | [263] |
| Valve Timing, Exhaust | [270] |
| Valve Timing, Gnome Monosoupape | [278] |
| Valve Timing, Intake | [270] |
| Valve Timing, Lag and Lead | [269] |
| Valve Timing Procedure | [277] |
| Valve Timing Practice | [267] |
| Valves, Electric Welded | [258] |
| Valves, Flat and Bevel Seat | [257] |
| Valves, Four per Cylinder | [284] |
| Valves, How Placed in Cylinder | [247] |
| Valves in Cages | [249] |
| Valves in Removable Heads | [249] |
| Valves, Materials Used for | [258] |
| Valves, Reseating | [426] |
| Vaporizer, Simple Forms of | [120] |
| V Engines, Cylinder Arrangement in | [102] |
| Vernier, How Used | [401] |
| W | |
| Wall Cooling, Losses in | [65] |
| Water Cooling by Natural Circulation | [227] |
| Water Cooling System | [224] |
| Weight of Airplane Motors | [21] |
| Wiring, Defects in | [373] |
| Wiring Magneto Ignition System | [179] |
| Wisconsin Engines | [531] |
| Wrenches, Forms of | [380] |
| Wristpin Retention | [293] |
| Wristpin Retention Locks | [295] |
| Wristpin Wear and Remedy | [442] |
| Z | |
| Zenith Carburetor, Action of | [137] |
| Zenith Duplex Carburetor, Troubles in | [356] |
| Zenith Carburetor Installation | [139] |
LIST OF ILLUSTRATIONS
| [Frontispiece.] | Part Sectional View of Hall-Scott Airplane Motor, Showing Principal Parts. |
| [Fig. 1.] | Diagrams Illustrating Computations for Horse-Power Required for Airplane Flight. |
| [Fig. 2.] | Plate Showing Heavy, Slow Speed Internal Combustion Engines Used Only for Stationary Power in Large Installations Giving Weight to Horse-Power Ratio. |
| [Fig. 3.] | Various Forms of Internal Combustion Engines Showing Decrease in Weight to Horse-Power Ratio with Augmenting Speed of Rotation. |
| [Fig. 4.] | Internal Combustion Engine Types of Extremely Fine Construction and Refined Design, Showing Great Power Outputs for Very Small Weight, a Feature Very Much Desired in Airplane Power Plants. |
| [Fig. 5.] | Outlining First Two Strokes of Piston in Four-Cycle Engine. |
| [Fig. 6.] | Outlining Second Two Strokes of Piston in Four-Cycle Engine. |
| [Fig. 7.] | Sectional View of L Head Gasoline Engine Cylinder Showing Piston Movements During Four-Stroke Cycle. |
| [Fig. 8.] | Showing Two-port, Two-cycle Engine Operation. |
| [Fig. 9.] | Defining Three-port, Two-cycle Engine Action. |
| [Fig. 10.] | Diagrams Contrasting Action of Two- and Four-Cycle Cylinders on Exhaust and Intake Stroke. |
| [Fig. 11.] | Diagram Isothermal and Adiabatic Lines. |
| [Fig. 12.] | Graphic Diagram Showing Approximate Utilization of Fuel Burned in Internal-Combustion Engine. |
| [Fig. 13.] | Otto Four-Cycle Card. |
| [Fig. 14.] | Diesel Motor Card. |
| [Fig. 15.] | Diagram of Heat in the Gas Engine Cylinder. |
| [Fig. 16.] | Chart Showing Relation Between Compression Volume and Pressure. |
| [Fig. 17.] | The Thompson Indicator, an Instrument for Determining Compressions and Explosion Pressure Values and Recording Them on Chart. |
| [Fig. 18.] | Spherical Combustion Chamber. |
| [Fig. 19.] | Enlarged Combustion Chamber. |
| [Fig. 20.] | Mercedes Aviation Engine Cylinder Section Showing Approximately Spherical Combustion Chamber and Concave Piston Top. |
| [Fig. 21.] | Side Sectional View of Typical Airplane Engine, Showing Parts and Their Relation to Each Other. This Engine is an Aeromarine Design and Utilizes a Distinctive Concentric Valve Construction. |
| [Fig. 22.] | Diagrams Illustrating Sequence of Cycles in One- and Two-Cylinder Engines Showing More Uniform Turning Effort on Crank-Shaft with Two-Cylinder Motors. |
| [Fig. 23.] | Diagrams Demonstrating Clearly Advantages which Obtain when Multiple-Cylinder Motors are Used as Power Plants. |
| [Fig. 24.] | Showing Three Possible Though Unconventional Arrangements of Four-Cylinder Engines. |
| [Fig. 25.] | Diagrams Outlining Advantages of Multiple Cylinder Motors, and Why They Deliver Power More Evenly Than Single Cylinder Types. |
| [Fig. 26.] | Diagrams Showing Duration of Events for a Four-Stroke Cycle, Six-Cylinder Engine. |
| [Fig. 27.] | Diagram Showing Actual Duration of Different Strokes in Degrees. |
| [Fig. 28.] | Another Diagram to Facilitate Understanding Sequence of Functions in Six-Cylinder Engine. |
| [Fig. 29.] | Types of Eight-Cylinder Engines Showing the Advantage of the V Method of Cylinder Placing. |
| [Fig. 30.] | Curves Showing Torque of Various Engine Types Demonstrate Graphically Marked Advantage of the Eight-Cylinder Type. |
| [Fig. 31.] | Diagrams Showing How Increasing Number of Cylinders Makes for More Uniform Power Application. |
| [Fig. 32.] | How the Angle Between the Cylinders of an Eight- and Twelve-Cylinder V Motor Varies. |
| [Fig. 33.] | The Hall-Scott Four-Cylinder 100 Horse-Power Aviation Motor. |
| [Fig. 34.] | Two Views of the Duesenberg Sixteen Valve Four-Cylinder Aviation Motor. |
| [Fig. 35.] | The Hall-Scott Six-Cylinder Aviation Engine. |
| [Fig. 36.] | The Curtiss Eight-Cylinder, 200 Horse-Power Aviation Engine. |
| [Fig. 37.] | The Sturtevant Eight-Cylinder, High Speed Aviation Motor. |
| [Fig. 38.] | Anzani 40-50 Horse-Power Five-Cylinder Air Cooled Engine. |
| [Fig. 39.] | Unconventional Six-Cylinder Aircraft Motor of Masson Design. |
| [Fig. 40.] | The Gnome Fourteen-Cylinder Revolving Motor. |
| [Fig. 41.] | How Gravity Feed Fuel Tank May Be Mounted Back of Engine and Secure Short Fuel Line. |
| [Fig. 42.] | The Stewart Vacuum Fuel Feed Tank. |
| [Fig. 43.] | Marine-Type Mixing Valve, by which Gasoline is Sprayed into Air Stream Through Small Opening in Air-Valve Seat. |
| [Fig. 44.] | Tracing Evolution of Modern Spray Carburetor. A—Early Form Evolved by Maybach. B.—Phœnix-Daimler Modification of Maybach’s Principle. C—Modern Concentric Float Automatic Compensating Carburetor. |
| [Fig. 45.] | New Model of Schebler Carburetor With Metering Valve and Extended Venturi. Note Mechanical Connection Between Air Valve and Fuel Regulating Needle. |
| [Fig. 46.] | The Claudel Carburetor. |
| [Fig. 47.] | The Stewart Metering Pin Carburetor. |
| [Fig. 48.] | The Ball and Ball Two-Stage Carburetor. |
| [Fig. 49.] | The Master Carburetor. |
| [Fig. 50.] | Sectional View of Master Carburetor Showing Parts. |
| [Fig. 51.] | Sectional View of Zenith Compound Nozzle Compensating Carburetor. |
| [Fig. 52.] | Diagrams Explaining Action of Baverey Compound Nozzle Used in Zenith Carburetor. |
| [Fig. 53.] | The Zenith Duplex Carburetor for Airplane Motors of the V Type. |
| [Fig. 54.] | Rear View of Curtiss OX-2 90 Horse-Power Airplane Motor Showing Carburetor Location and Hot Air Leads. |
| [Fig. 55.] | Types of Strainers Interposed Between Vaporizer and Gasoline Tank to Prevent Water or Dirt Passing Into Carbureting Device. |
| [Fig. 56.] | Chart Showing Diminution of Air Pressure as Altitude Increases. |
| [Fig. 57.] | Some Simple Experiments to Demonstrate Various Magnetic Phenomena and Clearly Outline Effects of Magnetism and Various Forms of Magnets. |
| [Fig. 58.] | Elementary Form of Magneto Showing Principal Parts Simplified to Make Method of Current Generation Clear. |
| [Fig. 59.] | Showing How Strength of Magnetic Influence and of the Currents Induced in the Windings of Armature Vary with the Rapidity of Changes of Flow. |
| [Fig. 60.] | Diagrams Explaining Action of Low Tension Transformer Coil and True High Tension Magneto Ignition Systems. |
| [Fig. 60A.] | Side Sectional View of Bosch High-Tension Magneto Shows Disposition of Parts. End Elevation Depicts Arrangement of Interruptor and Distributor Mechanism. |
| [Fig. 61.] | Berling Two-Spark Dual Ignition System. |
| [Fig. 62.] | Berling Double-Spark Independent System. |
| [Fig. 63.] | Type DD Berling High Tension Magneto. |
| [Fig. 64.] | Wiring Diagrams of Berling Magneto Ignition Systems. |
| [Fig. 65.] | The Berling Magneto Breaker Box Showing Contact Points Separated and Interruptor Lever on Cam. |
| [Fig. 66.] | The Dixie Model 60 for Six-Cylinder Airplane Engine Ignition. |
| [Fig. 67.] | Installation Dimensions of Dixie Model 60 Magneto. |
| [Fig. 68.] | The Rotating Elements of the Dixie Magneto. |
| [Fig. 69.] | Suggestions for Adjusting and Dismantling Dixie Magneto. A—Screw Driver Adjusts Contact Points. B—Distributor Block Removed. C—Taking off Magnets. D—Showing How Easily Condenser and High Tension Windings are Removed. |
| [Fig. 69A.] | Sectional Views Outlining Construction of Dixie Magneto with Compound Distributor for Eight-Cylinder Engine Ignition. |
| [Fig. 70.] | Wiring Diagram of Dixie Magneto Installation on Hall-Scott Six-Cylinder 125 Horse-Power Aeronautic Motor. |
| [Fig. 71.] | How Magneto Ignition is Installed on Thomas-Morse 135 Horse-Power Motor. |
| [Fig. 72.] | Spark-Plug Types Showing Construction and Arrangement of Parts. |
| [Fig. 73.] | Standard Airplane Engine Plug Suggested by S. A. E. Standards Committee. |
| [Fig. 74.] | Special Mica Plug for Aviation Engines. |
| [Fig. 75.] | Showing Use of Magnifying Glass to Demonstrate that Apparently Smooth Metal Surfaces May Have Minute Irregularities which Produce Friction. |
| [Fig. 76.] | Pressure Feed Oiling System of Thomas Aviation Engine Includes Oil Cooling Means. |
| [Fig. 77.] | Diagram of Oiling System, Hall-Scott Type A 125 Horse-Power Engine. |
| [Fig. 78.] | Sectional View of Typical Motor Showing Parts Needing Lubrication and Method of Applying Oil by Constant Level Splash System. Note also Water Jacket and Spaces for Water Circulation. |
| [Fig. 79.] | Pressure Feed Oil-Supply System of Airplane Power Plants has Many Good Features. |
| [Fig. 80.] | Why Pressure Feed System is Best for Eight-Cylinder Vee Airplane Engines. |
| [Fig. 81.] | Operating Temperatures of Automobile Engine Parts Useful as a Guide to Understand Airplane Power Plant Heat. |
| [Fig. 82.] | Water Cooling of Salmson Seven-Cylinder Radial Airplane Engine. |
| [Fig. 83.] | How Water Cooling System of Thomas Airplane Engine is Installed in Fuselage. |
| [Fig. 84.] | Finned Tube Radiators at the Side of Hall-Scott Airplane Power Plant Installed in Standard Fuselage. |
| [Fig. 85.] | Anzani Testing His Five-Cylinder Air Cooled Aviation Motor Installed in Bleriot Monoplane. Note Exposure of Flanged Cylinders to Propeller Slip Stream. |
| [Fig. 86.] | Views of Four-Cylinder Duesenberg Airplane Engine Cylinder Block. |
| [Fig. 87.] | Twin-Cylinder Block of Sturtevant Airplane Engine is Cast of Aluminum, and Has Removable Cylinder Head. |
| [Fig. 88.] | Aluminum Cylinder Pair Casting of Thomas 150 Horse-Power Airplane Engine is of the L Head Type. |
| [Fig. 90.] | Cross Section of Austro-Daimler Engine, Showing Offset Cylinder Construction. Note Applied Water Jacket and Peculiar Valve Action. |
| [Fig. 91.] | Diagrams Demonstrating Advantages of Offset Crank-Shaft Construction. |
| [Fig. 92.] | Diagram Showing Forms of Cylinder Demanded by Different Valve Placings. A—T Head Type, Valves on Opposite Sides. B—L Head Cylinder, Valves Side by Side. C—L Head Cylinder, One Valve in Head, Other in Pocket. D—Inlet Valve Over Exhaust Member, Both in Side Pocket. E—Valve-in-the-Head Type with Vertical Valves. F—Inclined Valves Placed to Open Directly into Combustion Chamber. |
| [Fig. 93.] | Sectional View of Engine Cylinder Showing Valve and Cage Installation. |
| [Fig. 94.] | Diagrams Showing How Gas Enters Cylinder Through Overhead Valves and Other Types. A—Tee Head Cylinder. B—L Head Cylinder. C—Overhead Valve. |
| [Fig. 95.] | Conventional Methods of Operating Internal Combustion Motor Valves. |
| [Fig. 96.] | Examples of Direct Valve Actuation by Overhead Cam-Shaft. A—Mercedes. B—Hall-Scott. C—Wisconsin. |
| [Fig. 97.] | CENSORED |
| [Fig. 98.] | CENSORED |
| [Fig. 99.] | Sectional Views Showing Arrangement of Novel Concentric Valve Arrangement Devised by Panhard for Aerial Engines. |
| [Fig. 100.] | Showing Clearance Allowed Between Valve Stem and Valve Stem Guide to Secure Free Action. |
| [Fig. 101.] | Forms of Valve-Lifting Cams Generally Employed. A—Cam Profile for Long Dwell and Quick Lift. B—Typical Inlet Cam Used with Mushroom Type Follower. C—Average Form of Cam. D—Designed to Give Quick Lift and Gradual Closing. |
| [Fig. 102.] | Showing Principal Types of Cam Followers which Have Received General Application. |
| [Fig. 103.] | Diagram Showing Proper Clearance to Allow Between Adjusting Screw and Valve Stems in Hall-Scott Aviation Engines. |
| [Fig. 104.] | Cam-Shaft of Thomas Airplane Motor Has Cams Forged Integral. Note Split Cam-Shaft Bearings and Method of Gear Retention. |
| [Fig. 105.] | Section Through Cylinder of Knight Motor, Showing Important Parts of Valve Motion. |
| [Fig. 106.] | Diagrams Showing Knight Sleeve Valve Action. |
| [Fig. 107.] | Cross Sectional View of Knight Type Eight Cylinder V Engine. |
| [Fig. 108.] | Diagrams Explaining Valve and Ignition Timing of Hall-Scott Aviation Engine. |
| [Fig. 109.] | Timing Diagram of Typical Six-Cylinder Engine. |
| [Fig. 110.] | Timing Diagram of Typical Eight-Cylinder V Engine. |
| [Fig. 111.] | Timing Diagram Showing Peculiar Valve Timing of Gnome “Monosoupape” Rotary Motor. |
| [Fig. 112.] | Two Methods of Operating Valves by Positive Cam Mechanism Which Closes as Well as Opens Them. |
| [Fig. 113.] | Diagram Comparing Two Large Valves and Four Small Ones of Practically the Same Area. Note How Easily Small Valves are Installed to Open Directly Into the Cylinder. |
| [Fig. 114.] | Sectional Views of Sixteen-Valve Four-Cylinder Automobile Racing Engine That May Have Possibilities for Aviation Service. |
| [Fig. 115.] | Front View of Curtiss OX-3 Aviation Motor, Showing Unconventional Valve Action by Concentric Push Rod and Pull Tube. |
| [Fig. 116.] | Forms of Pistons Commonly Employed in Gasoline Engines. A—Dome Head Piston and Three Packing Rings. B—Flat Top Form Almost Universally Used. C—Concave Piston Utilized in Knight Motors and Some Having Overhead Valves. D—Two-Cycle Engine Member with Deflector Plate Cast Integrally. E—Differential of Two-Diameter Piston Used in Some Engines Operating on Two-Cycle Principle. |
| [Fig. 117.] | Typical Methods of Piston Pin Retention Generally Used in Engines of American Design. A—Single Set Screw and Lock Nut. B—Set Screw and Check Nut Fitting Groove in Wrist Pin. C, D—Two Locking Screws Passing Into Interior of Hollow Wrist Pin. E—Split Ring Holds Pin in Place. F—Use of Taper Expanding Plugs Outlined. G—Spring Pressed Plunger Type. H—Piston Pin Pinned to Connecting Rod. I—Wrist Pin Clamped in Connecting Rod Small End by Bolt. |
| [Fig. 118.] | Typical Piston and Connecting Rod Assembly. |
| [Fig. 119.] | Parts of Sturtevant Aviation Engine. A—Cylinder Head Showing Valves. B—Connecting Rod. C—Piston and Rings. |
| [Fig. 120.] | Aluminum Piston and Light But Strong Steel Connecting Rod and Wrist Pin of Thomas Aviation Engine. |
| [Fig. 121.] | Cast Iron Piston of “Monosoupape” Gnome Engine Installed On One of the Short Connecting Rods. |
| [Fig. 122.] | Types of Aluminum Pistons Used In Aviation Engines. |
| [Fig. 123.] | Types of Piston Rings and Ring Joints. A—Concentric Ring. B—Eccentrically Machined Form. C—Lap Joint Ring. D—Butt Joint, Seldom Used. E—Diagonal Cut Member, a Popular Form. |
| [Fig. 124.] | Diagrams Showing Advantages of Concentric Piston Rings. |
| [Fig. 125.] | Leak-Proof and Other Compound Piston Rings. |
| [Fig. 126.] | Sectional View of Engine Showing Means of Preventing Oil Leakage By Piston Rings. |
| [Fig. 127.] | Connecting Rod and Crank-Shaft Construction of Gnome “Monosoupape” Engine. |
| [Fig. 128.] | Connecting Rod Types Summarized. A—Single Connecting Rod Made in One Piece, Usually Fitted in Small Single-Cylinder Engines Having Built-Up Crank-Shafts. B—Marine Type, a Popular Form on Heavy Engines. C—Conventional Automobile Type, a Modified Marine Form. D—Type Having Hinged Lower Cap and Split Wrist Pin Bushing. E—Connecting Rod Having Diagonally Divided Big End. F—Ball-Bearing Rod. G—Sections Showing Structural Shapes Commonly Employed in Connecting Rod Construction. |
| [Fig. 129.] | Double Connecting Rod Assembly For Use On Single Crank-Pin of Vee Engine. |
| [Fig. 130.] | Another Type of Double Connecting Rod for Vee Engines. |
| [Fig. 131.] | Part Sectional View of Wisconsin Aviation Engine, Showing Four-Bearing Crank-Shaft, Overhead Cam-Shaft, and Method of Combining Cylinders in Pairs. |
| [Fig. 132.] | Part Sectional View of Renault Twelve-Cylinder Water-Cooled Engine, Showing Connecting Rod Construction and Other Important Internal Parts. |
| [Fig. 133.] | Typical Cam-Shaft, with Valve Lifting Cams and Gears to Operate Auxiliary Devices Forged Integrally. |
| [Fig. 134.] | Important Parts of Duesenberg Aviation Engine. A—Three Main Bearing Crank-Shaft. B—Cam-Shaft with Integral Cams. C—Piston and Connecting Rod Assembly. D—Valve Rocker Group. E—Piston. F—Main Bearing Brasses. |
| [Fig. 135.] | Showing Method of Making Crank-Shaft. A—The Rough Steel Forging Before Machining. B—The Finished Six-Throw, Seven-Bearing Crank-Shaft. |
| [Fig. 136.] | Showing Form of Crank-Shaft for Twin-Cylinder Opposed Power Plant. |
| [Fig. 137.] | Crank-Shaft of Thomas-Morse Eight-Cylinder Vee Engine. |
| [Fig. 138.] | Crank-Case and Crank-Shaft Construction for Twelve-Cylinder Motors. A—Duesenberg. B—Curtiss. |
| [Fig. 139.] | Counterbalanced Crank-Shafts Reduce Engine Vibration and Permit of Higher Rotative Speeds. |
| [Fig. 140.] | View of Thomas 135 Horse-Power Aeromotor, Model 8, Showing Conventional Method of Crank-Case Construction. |
| [Fig. 141.] | Views of Upper Half of Thomas Aeromotor Crank-Case. |
| [Fig. 142.] | Method of Constructing Eight-Cylinder Vee Engine, Possible if Aluminum Cylinder and Crank-Case Castings are Used. |
| [Fig. 143.] | Simple and Compact Crank-Case, Possible When Radial Cylinder Engine Design is Followed. |
| [Fig. 144.] | Unconventional Mounting of German Inverted Cylinder Motor. |
| [Fig. 145.] | How Curtiss Model OX-2 Motor is Installed in Fuselage of Curtiss Tractor Biplane. Note Similarity of Mounting to Automobile Power Plant. |
| [Fig. 146.] | Latest Model of Curtiss JN-4 Training Machine, Showing Thorough Enclosure of Power Plant and Method of Disposing of the Exhaust Gases. |
| [Fig. 147.] | Front View of L. W. F. Tractor Biplane Fuselage, Showing Method of Installing Thomas Aeromotor and Method of Disposing of Exhaust Gases. |
| [Fig. 148.] | End Elevation of Hall-Scott A-7 Four-Cylinder Motor, with Installation Dimensions. |
| [Fig. 149.] | Plan and Side Elevation of Hall-Scott A-7 Four-Cylinder Airplane Engine, with Installation Dimensions. |
| [Fig. 150.] | CENSORED |
| [Fig. 151.] | CENSORED |
| [Fig. 152.] | CENSORED |
| [Fig. 153.] | Plan View of Hall-Scott Type A-5 125 Horse-Power Airplane Engine, Showing Installation Dimensions. |
| [Fig. 154.] | Three-Quarter View of Hall-Scott Type A-5 125 Horse-Power Six-Cylinder Engine, with One of the Side Radiators Removed to Show Installation in Standard Fuselage. |
| [Fig. 155.] | Diagram Showing Proper Installation of Hall-Scott Type A-5 125 Horse-Power Engine with Pressure Feed Fuel Supply System. |
| [Fig. 156.] | Diagram Defining Installation of Gnome “Monosoupape” Motor in Tractor Biplane. Note Necessary Piping for Fuel, Oil, and Air Lines. |
| [Fig. 157.] | Showing Two Methods of Placing Propeller on Gnome Rotary Motor. |
| [Fig. 158.] | How Gnome Rotary Motor May Be Attached to Airplane Fuselage Members. |
| [Fig. 159.] | How Anzani Ten-Cylinder Radial Engine is Installed to Plate Securely Attached to Front End of Tractor Airplane Fuselage. |
| [Fig. 160.] | Side Elevation of Thomas 135 Horse-Power Airplane Engine, Giving Important Dimensions. |
| [Fig. 161.] | Front Elevation of Thomas-Morse 135 Horse-Power Aeromotor, Showing Main Dimensions. |
| [Fig. 162.] | Front and Side Elevations of Sturtevant Airplane Engine, Giving Principal Dimensions to Facilitate Installation. |
| [Fig. 163.] | Practical Hand Tools Useful in Dismantling and Repairing Airplane Engines. |
| [Fig. 164.] | Wrenches are Offered in Many Forms. |
| [Fig. 165.] | Illustrating Use and Care of Files. |
| [Fig. 166.] | Outlining Use of Cotter Pin Pliers, Spring Winder, and Showing Practical Outfit of Chisels. |
| [Fig. 167.] | Forms of Hand Operated Drilling Machines. |
| [Fig. 168.] | Forms of Drills Used in Hand and Power Drilling Machines. |
| [Fig. 169.] | Useful Set of Number Drills, Showing Stand for Keeping These in an Orderly Manner. |
| [Fig. 170.] | Illustrating Standard Forms of Hand and Machine Reamers. |
| [Fig. 171.] | Tools for Thread Cutting. |
| [Fig. 172.] | Showing Holder Designs for One- and Two-Piece Thread Cutting Dies. |
| [Fig. 173.] | Useful Outfit of Taps and Dies for the Engine Repair Shop. |
| [Fig. 174.] | Common Forms of Inside and Outside Calipers. |
| [Fig. 175.] | Measuring Appliances for the Machinist and Floor Man. |
| [Fig. 176.] | At Left, Special Form of Vernier Caliper for Measuring Gear Teeth; at Right, Micrometer for Accurate Internal Measurements. |
| [Fig. 177.] | Measuring Appliances of Value in Airplane Repair Work. |
| [Fig. 178.] | Standard Forms of Micrometer Caliper for External Measurements. |
| [Fig. 179.] | Special Tools for Maintaining Curtiss OX-2 Motor Used in Curtiss JN-4 Training Biplane. |
| [Fig. 180.] | Special Tools and Appliances to Facilitate Overhauling Work on Hall-Scott Airplane Engines. |
| [Fig. 181.] | Special Stand to Make Motor Overhauling Work Easier. |
| [Fig. 182.] | Showing Where Carbon Deposits Collect in Engine Combustion Chamber, and How to Burn Them Out with the Aid of Oxygen. A—Special Torch. B—Torch Coupled to Oxygen Tank. C—Torch in Use. |
| [Fig. 1821⁄2.] | Part Sectional View, Showing Valve Arrangement in Cylinder of Curtiss OX-2 Aviation Engine. |
| [Fig. 183.] | Tools for Restoring Valve Head and Seats. |
| [Fig. 184.] | Tools and Processes Utilized in Valve Grinding. |
| [Fig. 185.] | Outlining Points in Valve Operating Mechanism Where Depreciation is Apt to Exist. |
| [Fig. 186.] | Method of Removing Piston Rings, and Simple Clamp to Facilitate Insertion of Rings in Cylinder. |
| [Fig. 187.] | Tools and Processes Used in Refitting Engine Bearings. |
| [Fig. 188.] | Showing Points to Observe When Fitting Connecting Rod Brasses. |
| [Fig. 189.] | Methods of Testing to Insure Parallelism of Bearings After Fitting. |
| [Fig. 190.] | Views Outlining Construction of Three-Cylinder Anzani Aviation Motor. |
| [Fig. 190a.] | Illustrations Depicting Wrong and Right Methods of “Swinging the Stick” to Start Airplane Engine. At Top, Poor Position to Get Full Throw and Get Out of the Way. Below, Correct Position to Get Quick Turn Over of Crank-Shaft and Spring Away from Propeller. |
| [Fig. 191.] | The Anzani Six-Cylinder Water-Cooled Aviation Engine. |
| [Fig. 192.] | Sectional View of Anzani Six-Cylinder Water-Cooled Aviation Engine. |
| [Fig. 193.] | Three-Cylinder Anzani Air-Cooled Y-Form Engine. |
| [Fig. 194.] | Anzani Fixed Crank-Case Engine of the Six-Cylinder Form Utilizes Air Cooling Successfully. |
| [Fig. 195.] | Sectional View Showing Internal Parts of Six-Cylinder Anzani Engine, with Starwise Disposition of Cylinders. |
| [Fig. 196.] | The Anzani Ten-Cylinder Aviation Engine at the Left, and the Twenty-Cylinder Fixed Type at the Right. |
| [Fig. 197.] | Application of R. E. P. Five-Cylinder Fan-Shape Air-Cooled Motor to Early Monoplane. |
| [Fig. 198.] | The Canton and Unné Nine-Cylinder Water-Cooled Radial Engine. |
| [Fig. 199.] | Sectional View Showing Construction of Canton and Unné Water-Cooled Radial Cylinder Engine. |
| [Fig. 200.] | Sectional View Outlining Construction of Early Type Gnome Valve-in-Piston Type Motor. |
| [Fig. 201.] | Sectional View of Early Type Gnome Cylinder and Piston Showing Construction and Application of Inlet and Exhaust Valves. |
| [Fig. 202.] | Details of Old Style Gnome Motor Inlet and Exhaust Valve Construction and Operation. |
| [Fig. 203.] | The Gnome Fourteen-Cylinder 100 Horse-Power Aviation Engine. |
| [Fig. 204.] | Cam and Cam-Gear Case of the Gnome Seven-Cylinder Revolving Engine. |
| [Fig. 205.] | Diagrams Showing Why An Odd Number of Cylinders is Best for Rotary Cylinder Motors. |
| [Fig. 206.] | Simple Carburetor Used On Early Gnome Engines Attached to Fixed Crank-Shaft End. |
| [Fig. 207.] | Sectional Views of the Gnome Oil Pump. |
| [Fig. 208.] | Simplified Diagram Showing Gnome Motor Magneto Ignition System. |
| [Fig. 209.] | The G. V. Gnome “Monosoupape” Nine-Cylinder Rotary Engine Mounted on Testing Stand. |
| [Fig. 210.] | Sectional View Showing Construction of General Vehicle Co. “Monosoupape” Gnome Engine. |
| [Fig. 211.] | How a Gnome Cylinder is Reduced from Solid Chunk of Steel Weighing 97 Pounds to Finished Cylinder Weighing 51⁄2 Pounds. |
| [Fig. 212.] | The Gnome Engine Cam-Gear Case, a Fine Example of Accurate Machine Work. |
| [Fig. 213.] | G. V. Gnome “Monosoupape,” with Cam-Case Cover Removed to Show Cams and Valve-Operating Plungers with Roller Cam Followers. |
| [Fig. 214.] | The 50 Horse-Power Rotary Bayerischen Motoren Gesellschaft Engine, a German Adaptation of the Early Gnome Design. |
| [Fig. 215.] | Nine-Cylinder Revolving Le Rhone Type Aviation Engine. |
| [Fig. 216.] | Part Sectional Views of Le Rhone Rotary Cylinder Engine, Showing Method of Cylinder Retention, Valve Operation and Novel Crank Disc Assembly. |
| [Fig. 217.] | Side Sectional View of Le Rhone Aviation Engine. |
| [Fig. 218.] | View Showing Le Rhone Valve Action and Connecting Rod Big End Arrangement. |
| [Fig. 219.] | Diagrams Showing Important Components of Le Rhone Motor. |
| [Fig. 220.] | How the Cams of the Le Rhone Motor Can Operate Two Valves with a Single Push Rod. |
| [Fig. 221.] | The Le Rhone Carburetor at A and Fuel Supply Regulating Device at B. |
| [Fig. 222.] | Diagrams Showing Le Rhone Motor Action and Firing Order. |
| [Fig. 223.] | Diagram Showing Positions of Piston in Le Rhone Rotary Cylinder Motor. |
| [Fig. 224.] | Diagrams Showing Valve Timing of Le Rhone Aviation Engine. |
| [Fig. 225.] | Diagrams Showing How Cylinder Cooling is Effected in Renault Vee Engines. |
| [Fig. 226.] | End Sectional View of Renault Air-Cooled Aviation Engine. |
| [Fig. 227.] | Side Sectional View of Renault Twelve-Cylinder Air-Cooled Aviation Engine Crank-Case, Showing Use of Plain and Ball Bearings for Crank-Shaft Support. |
| [Fig. 228.] | End View of Renault Twelve-Cylinder Engine Crank-Case, Showing Magneto Mounting. |
| [Fig. 229.] | Diagram Outlining Renault Twelve-Cylinder Engine Ignition System. |
| [Fig. 230.] | The Simplex Model A Hispano-Suiza Aviation Engine, a Very Successful Form. |
| [Fig. 231.] | The Curtiss OXX-5 Aviation Engine is an Eight-Cylinder Type Largely Used on Training Machines. |
| [Fig. 232.] | Top and Bottom Views of the Curtiss OXX-5 100 Horse-Power Aviation Engine. |
| [Fig. 233.] | End View of Thomas-Morse 150 Horse-Power Aluminum Cylinder Aviation Motor Having Detachable Cylinder Heads. |
| [Fig. 234.] | Side View of Thomas-Morse High Speed 150 Horse-Power Aviation Motor with Geared Down Propeller Drive. |
| [Fig. 235.] | The Reduction Gear-Case of Thomas-Morse 150 Horse-Power Aviation Motor, Showing Ball Bearing and Propeller Drive Shaft Gear. |
| [Fig. 236.] | The Six-Cylinder Aeromarine Engine. |
| [Fig. 237.] | The Wisconsin Aviation Engine, at Top, as Viewed from Carburetor Side. Below, the Exhaust Side. |
| [Fig. 238.] | Dimensioned End Elevation of Wisconsin Six Motor. |
| [Fig. 239.] | Dimensioned Side Elevation of Wisconsin Six Motor. |
| [Fig. 240.] | Power, Torque and Efficiency Curves of Wisconsin Aviation Motor. |
| [Fig. 241.] | Timing Diagram, Wisconsin Aviation Engine. |
| [Fig. 242.] | Dimensioned End View of Wisconsin Twelve-Cylinder Airplane Motor. |
| [Fig. 243.] | Dimensioned Side Elevation of Wisconsin Twelve-Cylinder Airplane Motor. |
| [Fig. 244.] | Side and End Sectional Views of Four-Cylinder Argus Engine, a German 100 Horse-Power Design Having Bore and Stroke of 140 mm., or 5.60 inches, and Developing Its Power at 1,368 R.P.M. Weight, 350 Pounds. |
| [Fig. 245.] | Part Sectional View of 90 Horse-Power Mercedes Engine, Which is Typical of the Design of Larger Sizes. |
| [Fig. 246.] | Part Sectional Side View and Sectional End View of Benz 160 Horse-Power Aviation Engine. |
| [Fig. 247.] | At Top, the Sunbeam Overhead Valve 170 Horse-Power Six-Cylinder Engine. Below, Side View of Sunbeam 350 Horse-Power Twelve-Cylinder Vee Engine. |
| [Fig. 248.] | Side View of Eighteen-Cylinder Sunbeam Coatalen Aircraft Engine Rated at 475 B.H.P. |
| [Fig. 249.] | Sunbeam Eighteen-Cylinder Motor, Viewed from Pump and Magneto End. |
| [Fig. 250.] | Propeller End of Sunbeam Eighteen-Cylinder 475 B.H.P. Aviation Engine. |
| [Fig. 251.] | View of Airplane Cowl Board, Showing the Various Navigating and Indicating Instruments to Aid the Aviator in Flight. |
| [Fig. 252.] | Parts of Christensen Air Starting System Shown at A, and Application of Piping and Check Valves to Cylinders of Thomas-Morse Aeromotor Outlined at B. |
| [Fig. 253.] | Diagrams Showing Installation of Air Starting System on Thomas-Morse Aviation Motor. |