The Aviator and the Weather Bureau

by Ford A. Carpenter

Record of Avalon Ascents, July-August, 1913

Table showing Theodolite observations of wind velocities (meters per second)
at elevations of 1,000 and 5,000 meters

Meters	Meters per second 5 p.m. July 24	Meters per second 5 p.m. July 27	Meters per second 10 a.m. July 31	Meters per second 10 a.m. Aug. 1	Meters per second 10 a.m. Aug. 2	Meters per second 5 p.m. Aug. 3	Meters per second 4 p.m. Aug. 7	Meters per second 5 p.m. Aug. 8	Mean
1,000	2.5	1.0	5.6	6.6	2.3	5.8	7.1	1.9	4.1
1,500	6.2	0.8	6.2	8.1	3.3	5.0	6.4	1.5	4.7
2,000	8.0	1.2	5.8	7.0	4.1	4.5	6.5	6.0	5.4
2,500	10.0	1.8	10.8	5.7	5.2	4.2	4.7	3.6	5.8
3,000	12.0	2.3	9.4	6.1	7.2	5.2	3.5	4.1	6.2
3,500	12.8	2.5	8.0	6.7	7.4	6.1	4.6	4.6	6.6
4,000	13.6	3.8	11.2	7.4	9.2	5.2	6.4	3.2	7.5
4,500	14.3	5.2	14.6	8.5	11.2	1.8	7.8	3.0	8.3
5,000	21.2	6.2	12.8	10.3	10.4	2.3		3.4	9.5

Charts Showing Upper-air Weather Conditions.—It is believed that the following charts when examined in connection with the accompanying explanation in the text will give the reader something of an outline as to the conditions existing in the upper regions of the atmosphere.

CHART NO. 1

Horizontal Projections of the Paths of the Sounding Balloons Liberated at Avalon, California, July 23 to August 10, 1913

Reproduced from the Monthly Weather Review, 42: 423

This figure shows the horizontal projections as far as the balloon was observed, not the entire distance traveled until it landed.

CHART NO. 2

Vertical Temperature Gradient, Avalon, California, July 27, 1913

Solid line represents the ascent of the recording apparatus, the dotted line the descent. (Verticals 25° C. or 45° F.)

Reproduced from the Monthly Weather Review, 42: 412

CHART NO. 3

Mean Vertical Temperature Gradient

Figure reproduced from Monthly Weather Review, 42: 413.

Altitude values are in kilometers at the left, and in miles at the right: Temperature values are in Centigrade at bottom, in Fahrenheit at top.

Maximum airplane altitude 26,242 feet or 5 miles.

CHART NO. 4

Diagram Showing Increase of Wind with Elevation Data from Eight Meteorographs

From the article “Free Air Data in Southern California, July and August, 1913” by Dr. Wm. R. Blair, Professor of Meteorology, in the Monthly Weather Review, for July, 1914, it is learned that the wind shifts from west to east rather abruptly at 16 to 20 km. (10 to 12 miles); below this level down to about 5 km. (3 miles) it is quite uniformly from the west. Extremes: Maximum wind velocity 21.2 miles, 5,000 meters elevation, 5 P.M., July 24; minimum wind velocity 0.8 miles, 1,500 meters elevation, 5 P.M., July 27.

The table shows a steady increase in velocity of the wind with elevation, the data being obtained from the eight meteorographs. There were four morning flights (July 31, August 3, 7, 8) and five afternoon flights (July 24, 27, August 3, 7, 8, 1913), and elevations were computed for nine heights, 1,000 to 5,000 meters. Beyond the 5,000 meters the records show that from 2 to 7 miles altitude the wind increases at approximately the same rate that the density of the air decreases.

CHART NO. 5

Chart Showing Number of Flights and Duration in Hours for the Months of July to December, 1915, and January to August, 1916

Prepared by the War Department, Signal Corps Aviation School, San Diego, California, and furnished through the courtesy of Col. W. A. Glassford, Signal Corps, U. S. Army, Commanding Officer, September 14, 1916.

Fig. 1. Congressional Medal Awarded Wright Brothers

(Designed by Morgan)

This medal was awarded Orville and Wilbur Wright by resolution of Congress, March 4, 1909. Bronze replica in possession of the writer.

Photographed May 31, 1916, by permission of the Director of the Mint, Philadelphia

Fig. 2. Ascent of Sounding-Balloons at Avalon

Photographed July 27, 1913

This set was liberated from the base of the U. S. Weather Bureau, Avalon, Catalina Island, California, at 4.57 P.M., July 27, 1913, and rose to a height of 23,870 meters in one hour and three quarters when one of the balloons burst and the descent began. This was observed by Carpenter at the theodolite.

Fig. 3. Metrograph Which Made the Ascent of July 27, 1913

Photographed August, 1913

This meteorograph rose to a height of 23,870 meters (94,716 feet), at which height the pressure was 23 mm. (0.906 inches), temperature -52.1 C (-58 F.), relative humidity 21 per cent, wind E. (or more precisely S. 79 degrees E.), velocity 6.1 m.p.s. (14 miles per hour), but the minimum temperature was registered at 15,228 meters (49,960 feet) when the thermometer showed -64.7 C. (-85 F.), at which time the pressure was 89 mm. (3.504 inches of the barometer), relative humidity 19 per cent, wind N.W., 3.4 m.p.s. (8 miles per hour).

The basket was picked up at sea off Oceanside, San Diego County, about 90 km. (145 miles) east of Avalon.

For the first 6 miles of ascension the balloon moved upward at the rate of 8 miles per hour.

Fig. 4. First Flight of Airplane Carrying Two Persons

Photographed September 10, 1908

This photograph was made at Fort Meyer, Virginia, of the original Wright biplane, piloted by Mr. Orville Wright With Colonel G. O. Squier, U. S. A., as first passenger.

When this photograph was made no fatalities in airplane flight had occurred; the first victim, Lieutenant Selfridge, U. S. A., was killed while riding with Mr. Wright in the same biplane shown above, on the Tuesday following the Saturday this photograph was made, the machine falling to the ground at a spot which is practically the center of the picture, but near the trees which are part of Arlington National Cemetery.

Fig. 5. Mount Wilson Observatory

Photographed December 24, 1915

A special meteorological station of the Weather Bureau was established on Mount Wilson, December 25, 1915, and on April 1, 1916, daily reports of temperature, weather, precipitation, relative humidity, fog and other conditions were first telegraphed to the local office of the Weather Bureau at Los Angeles for publication and distribution.

The photograph shows the location of the meteorological observatory(*) and the valleys below. From the elevation of the observatory (6,000 feet above sea-level), it is possible for the observer to determine the thickness and extent of fog as it is feasible to see as far southwesterly as Point Loma on a clear day, and southerly to Santa Catalina Island. Such observations and reports have been made and forwarded without interruption to date. They have proven of incalculable value to the aviators making cross-country flights.

The station on Mount Wilson is maintained through the coöperation of the Carnegie Institute of Washington.

Fig. 6. Type of Airplane Used in 1911 on North Island

Photographed October, 1911

This photograph of Mr. Glenn Curtiss in his “pusher” airplane was made shortly after the Curtiss School of Flying was established in 1911, on North Island. At his right is Local Forecaster Carpenter.

Comparison of this machine, which four years ago was the last word in airplanes, with the tractor shown on the opposite page, indicates the rapid progress in design.

Fig. 7. Discussing a Flight

Photographed October 18, 1915

Aviation Instructor Oscar Brindley discussing a flight with Captain Clarke, U. S. A., and other officers at the U. S. Aviation School at San Diego.

Mr. Brindley is standing by the side of Captain Clarke in the group at the right. After every flight the Instructor reviews, point by point, the features of the flight, showing the pupil his deficiencies and explaining how he may avoid them in the future.

The officer at the left, Lieutenant Brown, has the regulation leather leggings, coat and helmet, and is ready to go up as soon as the mechanicians (who may be seen at the extreme left) finish inspection and pronounce the airplane fit for the next flight.

Fig. 8. Captain Culver and Parachute

Photographed October 21, 1915

Captain C. C. Culver, U. S. Cavalry, Adjutant, Aviation School, with a parachute in his hand, having word with Captain L. W. Patterson, U. S. A., before the latter’s flight. The object of the parachute is to determine changing wind-direction at different heights.

The airplane wireless record is now held by Captain Culver. In October, 1916, he sent a message 119 miles from Santa Monica to San Diego, California, while flying at an altitude of 1½ miles. He received a radio message from a distance of 11 miles while flying 7,000 feet aloft. He is also the first military aviator to rig up two airplanes so that they could exchange messages while in flight. The radio set used weighed less than forty-five pounds.

Fig. 9. Lieutenant Gorrell, U. S. Infantry, As Observer

Photographed October, 1915

The noise of the motor, together with the terrific blast of air, makes conversation impossible between the pilot and observer; for that reason telephones are sometimes installed as noted in this photograph.

Lieut. Edgar S. Gorrell is shown as the observer in this photograph. He has since qualified as an aviator and made a brilliant record in the Mexican activities in 1916.

Fig. 10. Point Loma from the Eastern Shore of North Island

Photographed October, 1915

The peninsula of Point Loma rises to an elevation approximating 500 feet, and as it lies approximately north and south, it interposes a considerable barrier to the prevailing westerly winds. The eastern side of Point Loma is very precipitous. These factors tend to produce winds called “woollies” which are a distinct menace to all small boats and air-craft, unless the air-craft have an elevation exceeding 3,000 feet on a normal windy day.

Fig. 11. San Diego, across Spanish Bight, as Seen from the U. S. Aviation School at Twilight

Photographed October, 1915

Contrasted with the photograph of Point Loma on the opposite page, this picture shows the ideal water conditions for trying out seaplanes. Shortly before this picture was taken, one of the pilots of the Curtiss Aviation School, also on North Island drove a big seaplane 100 miles per hour barely skimming the surface of the water.

Fig. 12. Instructor Brindley and Meteorologist Carpenter in Military Tractor No. 50

Photographed October 20, 1915

Instructor Oscar Brindley and the observer, Meteorologist Ford A. Carpenter, U. S. Weather Bureau, leaving the ground for a flight. In the military tractor used generally by the Army, the observer sits forward while the pilot occupies the after cockpit. This machine, like all others used in the military service, has dual control.

Fig. 13. Military Tractor No. 50. Type of Biplane Used in U. S. Army Service Made by Glenn Martin, Los Angeles, Cal.

Photographed October, 1915

Motor, horsepower, 80: revolutions per minute, 1,277.
Diameter of propeller, 8 feet.
Load of 39 gallons gasoline, 2½ gallons oil.
Flying radius with normal equipment, two persons, 300 miles.
Maximum altitude obtained with this model at San Diego, 13,000 feet.
Wing-spread, tip to tip, upper, 38 feet, 10 inches; lower, 34 feet, 10 inches.
Supporting area, upper, 139 square feet; lower, 165 square feet; total, 364 square feet.
Length of fuselage from rear of propeller hub, 21 feet, 6¾ inches.
Data from Major F. P. Lahm, Signal Corps, U. S. A.
Dated May 9, 1916.

Fig. 14. “Trimming” a Tractor in Leaving the Ground

Photographed October, 1915

Military Tractor No. 50 just before leaving the ground. In gusty weather the mechanicians steady the ends of the lower planes, sometimes turning it by holding one edge and pushing the other. In the photograph the mechanicians are giving the airplane steerageway to the right.

Fig. 15. Military Tractor No. 50 Just Leaving the Ground

Photographed October, 1915

Before attempting to leave the ground there is always considerable jockeying for a favorable head-wind, and the photograph shows Instructor Brindley maneuvering for a favorable pointing.

After leaving the ground, the wind, so long as it is not gusty, makes no difference to the pilot.

Fig. 16. San Diego Harbor at Over 2,000 Feet Altitude

Photographed October, 1915

The new municipal wharves are in the middle foreground and to their right may be seen the Santa Fé station. Part of North Island is obscured by cloud.

Fig. 17. Thirty-five Hundred Feet Above San Diego

Photographed October, 1915

This photograph was made 1,000 feet above the clouds. The wharves of San Diego and Coronado may be seen in the foreground and in the middle distance.

Fig. 18. Military Tractor No. 50 at 3,500 Feet Altitude

Photographed October 20, 1915

The airplane, in which the pilot, Oscar Brindley and the observer, Meteorologist Carpenter, made their flight, was photographed at the maximum elevation, 3,500 feet above the aviation field.

Fig. 19. Flying Squad’s Wind-Direction Pennant on Tower

Photographed October 5, 1915

The regular observation tower from which all observations and notes on every flight are made is just back of the headquarters building. The station anemometer is on the tower, and the portable anemometer is to the left.

Fig. 20. The Aviation School Motor-Boat “Pronto”

Photographed October, 1915

During the flying periods, the motor-boat of the U. S. Aviation School is kept ready for instant service in order to work in conjunction, if needs be, with the Medical Corps emergency truck on land.

Such is the speed of this boat (exceeding 40 miles per hour) that the water no longer has resiliency, and it is about as comfortable as riding in an old-fashioned stone-boat over rocky pastures.

Fig. 21. U. S. Aviation Field at Three Thousand Feet Altitude

Photographed October, 1915

Part of Coronado and the portion of land called North Island, separated by Spanish Bight. Point Loma may be seen at the extreme upper right-hand corner of the photograph. The flying-machine sheds, buildings of the Aviation School, etc., may be seen in the immediate foreground. The U. S. Cavalry camp is the white splotch in the center foreground.

Fig. 22. Repair Shop U. S. Aviation School, San Diego, Cal.

Photographed October, 1915

In the repair shop of the U. S. Aviation School at North Island the motors are given a gruelling test, being run twenty-four consecutive hours at a speed greater than that given them in actual practice. After this run they are taken down and each part is spread out on a large drawing-table and is subjected to close scrutiny so as to show any defect. Several airplanes as well as seaplanes have been reconstructed in this shop.