Langley Memoir on Mechanical Flight, Parts I and II / Smithsonian Contributions to Knowledge, Volume 27 Number 3, Publication 1948, 1911

by S. P. Langley; Charles M. Manly

Parts.	Sizes.		Weight.
	m.	ft.	gr.	lbs.
1 Frame, including everything of metal, permanent and undetachable, such as bed-plate, cross-rods for the support of propellers, bearing points for clutch, etc.			1178
2 Engine, gears, shafts, etc.			1043
3 Pump, pump shaft			190
4 Hull covering			345
5 Gasoline tanks, valves			306
6 Smokestack, 302; burner, 172			474
7 Float			275
8 Reel			77
9 Wing clamps, 238; drop piece for rudder, 40			278
10 Other things			156
11 Boiler, frames, mica cover			694
12 Separator, steam gauge, pipe to engines			535
13 Exhaust pipe			82
14
15
16
17 Wings (without clamp), wet			2154
18 Tail (without clamp)
19 Rudder			375
20 Guy sticks, each 53			106
21 Propellers			644
22 Extra length of midrod			398
23 Wood bowsprit			135
24 Counter			75
25
26
27 Fuel (at starting flight)			250
28 Water (at starting flight)			2350
29
30
31 Sundries unknown
32
33
34 Total flying weight			12,120
35
36
37
38 Total area of support (not including tail) . . . sq. ft.		54
39 Total area of support in feet, divided by total flying weight in lbs.		2
40 Total area of horizontal tail . . . sq. ft.	.6
41 Total area of rudder (vertical) . . . sq. ft.	.6
42 Horse-power at brake. . .Horse-power by formula*
43 Minimum steam pressure during 40 secs. lift				130
44 Lift at pendulum (during one minute absolute)				7,211
45 Lift at pendulum (during one minute in terms of wt.)
46 Minimum pressure with which wheels turn				10
47 Position of center of pressure of wings†
48 Time of getting up full steam, 75 secs.
49 Angle of midrod with horizon, 2° 17′
50 Curvature of wings, 1 in 18, 1/4 from front
51 Root angle of wings, 10° 30′
52 Tip angle of wings, 10° 30′
53 Position of wings
54 How guyed
55
56
57
58 Position of tail
59 Angle of tail
60 Co-efficient elasticity of tail
61 Position of rudder
62
63 Line of thrust 1500
64 Center of gravity1 of whole, 1483.8
65 Center of gravity2, 2482‡
66 Center of pressure1 of whole estimate, 1487
67 Center of pressure2, 2520
68
69
70
71
72

Parts. Remarks.

• 1 Front end of bowsprit, 1797.
• 2 Center of float in first trial, Nov.
• 6 Front end of midrod, 1613.7. 9 Front edge of F. W., 1595.7.
• 12 Center of float in flight, Nov. 28, 1896, 1575.8.
• 16 C. of P. on F. W., 1563.7.
• 19 Back edge of F. W., 1515.7.
• 22 Line through center
• of propellers, 1500.
• 26 C. of G., 1484.4 (old C. of G., 1486.3).
• 29 Front edge of R. W., 1406.
• 32 C. of P. on R. W., 1374.
• 35 End of midrod, 1351.3
• 38 Front end of rudder, 1334.5.
• 41 Back edge of R. W., 1326.
• 43 Center of rudder, 1279.
• 46 Back end of rudder, 1220.5.
• 49 Reed wings, 80 cm. × 185 cm. in rectangle.
• 53 Weight in shop, 1982 g.
• 56 On day of flight they weighed 2154 g. because they were damp.
• 60 Area 54 sq. ft.
• 63 Spread of wings, 359 cms. or 11′ 938″.
• 67 Weight of aerodrome in flight, 12,120 grs.

Footnotes.

• * H. P. = (Rev. × diam. × pitch ratio × thrust)/33000
• † This is calculated on the assumption that the center of pressure on each wing or on pair of wings at a motion of 2000 feet per minute is in ordinary curved wings 2-5 the way from front to rear, that for wings of usual size the rear wings have 2-3 of the efficiency per surface of the front ones and that the tail proper bears no part of the weight; but if rear wing is smaller or larger this efficiency is smaller or larger per unit of surface.
• ‡ This is undoubtedly incorrect, as if it were true, the C. G. would be just at the center of the separator, and this would be impossible. Mr. Reed states that the C. G. was 2 cm. below the side frame, and if this is correct, we would have C. G. = 2486.

[p299]

DATA SHEET No. 3. Weight of Aerodrome No. 6, Flat Wings and Pénaud Rudder. Certified to by Chas. M. Manly, June 7, 1899.

Parts.	Sizes.		Weight.
	m.	ft.	gr.	lbs.
1 Frame, including everything of metal, permanent and undetachable, such as bed-plate, cross-rods for the support of propellers, bearing points for clutch, etc.			2867
2 Engine, gears, shafts, etc.
3 Pump, 123; pump shaft, 49			172
4 Hull covering, including apron and piece behind separator			274
5 Gasoline and air tanks, 167, 114; air valve, 16			297
6 Smokestack, 319; counter, 95; burner, 165			679
7 Float, 275; pipe from pump to boiler, 40			315
8 Reel, with fork and float			128
9 Wing clamps, 188; guy-post clamps, 24			212
10 Boiler, 764; steam gauge and connections, 79			843
11 Front lower bearing post, 75; clutch post, 58; rear bearing points, 155			288
12 Separator and pipes leading to engines and pump			502
13 Drop piece for rudder, 57; guy-post for rudder, 18			75
14
15
16
17 Wings (without clamp)			2077
18 Superposed wings, 3448
19 Rudder			323
20 Guy sticks, each 53			106
21 Propellers			620
22 Extra length of midrod			377
23 Wood bowsprit			128
24 Canvas keel, 36; rudder, 76			112
25
26
27 Fuel (at starting flight)			175
28 Water (at starting flight)			1525
29
30
31 Sundries unknown
32
33
34 Total flying weight			11,995	26.44
35
36
37
38 Total area of support (not including tail) . . . sq. ft.		54
39 Total area of support in feet, divided by total flying weight in lbs.		2.04
40 Total area of horizontal tail . . . sq. ft.		9.5
41 Total area of rudder (vertical) . . . sq. ft.		7.75
42 Horse-power at brake . . . Horse-power by formula*
43
44 Lift at pendulum (during one minute absolute)
45 Lift at pendulum (during one minute in terms of wt.)
46 Minimum pressure with which wheels turn
47 Position of center of pressure of wings† 40% from front
48
49
50 Curvature of wings, 1 in 18
51 Root angle of wings, 10°
52 Tip angle of wings, 10°
53 Position of wings—front edge of front wing, 1595.7; of rear wing, 1406.5
54 How guyed—with wires from wing to wing on top and to guy-post on bottom
55
56
57
58 Position of center of rudder, 1279.5
59 Angle of tail, 10°
60 Co-efficient elasticity of tail
61 Position of rudder
62
63 Line of thrust, 1500
64 Center of gravity1 of whole, 1484.4
65 Center of gravity2
66 Center of pressure1 of whole estimate
67 Center of pressure2
68
69
70
71
72

Parts. Remarks.

• 1 Front edge of bowsprit, 1702.7. Weight 2867 gm. for part 1 includes also part 2.
• 2 Center of float with small wind vane rudder, 1628.9.
• 6 Front edge of midrod, 1613.7.
• 9 Center of float with small rudder off, 1609.2.
• 12 Front edge of F. W., 1595.7.
• 15 C. of P. on F. W., 1563.7.
• 18 Back edge of F. W., 1515.7.
• 21 Line through center of propellers, 1500.
• 25 C. of G., 1484.4.
• 28 Front edge of R. W., 1406.5.
• 31 C. of P. on R. W., 1374.5.
• 34 End of midrod, 1351.8.
• 37 Front end of rudder, 1335.
• 39 Back edge of R. W., 1326.5.
• 42 Center of rudder, 1279.5.
• 45 Back end of rudder, 1221.