In 1931 the model 6A (ATC 365) sold for $8500, increasing to $10,250 in 1931. Seven were built in total. Four evaluation models for Army military trials as YPT-9, and three civil; NX786H later modified as 6-D, -F and -L, NC787H later as 6-P, and NC795H later as 6-L.
Stearman YPT-9 Cloudboy Article
The 1933 6-C Cloudboy (ATC 2-457) was a modification of N2143 c/n 6010 with a canopied cockpit and repowered with a 330hp Wright J-6.
The 1931 model 6D Cloudboy (ATC 402) sold for $10,500, increasing to $12,750. One was built from 6-A as NC786H, later repowered with a 210hp Kinner (as 6-H) and then 215hp Lycoming (as 6-L), and finally converted into Army YBT-5.
Seven of the 6-F Cloudboy (ATC 371) were built. Four went to the USAAC as YPT-9 and YBT-5, and three converted to 6-H and 6-L (NC786H-788H]). YPT-9 31-462 was repowered with a 300hp P&W R-985-1 as YBT-5 and two other YPT-9s, 31-459 and 31-460, were converted.
In 1930 the model 6F sold for $7945, increasing to $9460 in 1931.
There were two conversions to the 1932 6-H Cloudboy (ATC 458) from older models (NC564Y and NC786H).
In 1932 four conversions from 6-A (NC795H) and -F (NC786H-788H) were made as 6-L Cloudboy (ATC 459), powered by a 215hp Lycoming R-680 engine. They were Army version YPT-9B.
One model 6-F, NC797H, was converted to the 1931 model 6-P (ATC 2-520) powered with a 220hp Wright J-5 engine.
The 1932 PT-9 primary trainer was adapted from civil Model 6 Cloudboy series with a 210hp Kinner engine. Four YPT-9 were built – 31-459 to 31-462 – testing various engines.
31-459 became YPT-9A, then -9B. 31-461 became YBT-3 and YPT-9C. 31-459 and 31-460 ultimately became BT-5.
The 1932 YPT-9C 31-461, first designated YBT-3, then YPT-9C, was powered with a 170hp Kinner R-720 and had the same specifications as the model 6-H.
6A Cloudboy
Engine: Wright J6-5, 165hp
Length: 24 ft 8 in
Height: 9 ft 6 in
Wing span upper: 32 ft
Wingspan lower: 28 ft
Chord: 60 in
Wing area: 272 sq.ft
Airfoil: N-22
Empty wt: 1733 lb
Max weight: 2400 lb
Useful load: 667 lb
Fuel capacity: 37 USG
Oil cap: 2.5 USG
Ceiling: 12,300 ft
Range: 350 sm
Max speed: 110 mph
Cruise: 90 mph
Stall: 45 mph
Seats: 2
6-C Cloudboy
Engine: 330hp Wright J-6
Seats: 2
6D
Engine: Pratt & Whitney Wasp Jnr, 300hp
Length: 24 ft 8 in
Height: 9 ft 7 in
Wing span upper: 32 ft
Wingspan lower: 28 ft
Wing area: 248 sq.ft.
Airfoil: N-22
Empty wt: 1952 lb
Max weight: 2814 lb
Useful load: 862 lb
Payload: 257 lb
Fuel capacity: 65 USG
Oil cap: 6 USG
Max speed: 137 mph
Cruise: 117 mph
Stall: 55 mph
Ceiling: 18,100 ft
Range: 450 sm
Seats: 2
6F
Engine: Continental A-70, 165hp
Length: 24 ft 8 in
Height: 9 ft 6 in
Wing span upper: 32 ft
Wingspan lower: 28 ft
Chord: 60 in
Wing area: 272 sq.ft
Airfoil: N-22
Empty wt: 1727 lb
Max weight: 2400 lb
Useful load: 673 lb
Fuel capacity: 37 USG
Oil cap: 2.5 USG
Ceiling: 12,300 ft
Range: 350 sm
Max speed: 110 mph
Seats: 2
6H
Engine: Kinner C5, 210hp
Length: 23 ft 11 in
Height: 9 ft 7 in
Wing span upper: 32 ft
Wingspan lower: 28 ft
Chord: 60 in
Wing area: 272.2 sq.ft
Airfoil: N-22
Empty wt: 1810 lb
Max weight: 2476 lb
Useful load: 666 lb
Payload: 230 lb
Fuel capacity: 66 USG
Oil cap: 5 USG
Ceiling: 15,200 ft
Range: 300-500 sm
Max speed: 119 mph
Cruise: 100 mph
Stall: 47 mph
Seats: 2
6L
Engine: Lycoming R-680, 215hp
Length: 23 ft 8 in
Height: 9 ft 7 in
Wing span upper: 32 ft
Wingspan lower: 28 ft
Chord: 60 in
Wing area: 272 sq.ft
Airfoil: N-22
Empty wt: 1880 lb
Max weight: 2551 lb
Useful load: 671 lb
Payload: 235 lb
Fuel capacity: 38 USG / 63 USG opt.
Oil cap: 5 USG
Ceiling: 15,000 ft
Range: 300-500 sm
Max speed: 120 mph
Cruise: 100 mph
Stall: 47 mph
Seats: 2
6P
Engine: Wright J5, 220hp
Length: 23 ft 8 in
Height: 9 ft 7 in
Wing span upper: 32 ft
Wingspan lower: 28 ft
Chord: 60 in
Wing area: 272 sq.ft
Airfoil: N-22
Max weight: 2500 lb
Fuel capacity: 37 USG
All Aero 