Common Specifications
Overall Span 30 ft. 0 in.
Overall Length 21 ft. 5-3/8 in.
Overall Height, Thrust Line Level at Fin 9 ft. 1-3/4 in.
Overall Height, At Rest (At Engine Cowl) 6 ft. 11-1/2 in.
Height, Propeller Hub, Thrust Line Leve l 5 ft. 3-3/8 in.
Height, Propeller Hub, at Rest 6 ft. 3 in.
Clearance, Propeller Tips, Thrust Line Level 1 ft. 11 in.
Propeller Diameter 80 in.
Wing
Total Area (Including Aileron and Flaps) 124 sq.ft.
Chord 56 in.
Incidence 3 deg 0 min
Dihedral 4 deg 30 min
Sweepback 0 deg
Airfoil NACA 2412
Area of Other Surfaces
Aileron 5.693 sq.ft.
Flap 6.270 sq.ft.
Stabilizer 12.000 sq.ft.
Elevator 10.000 sq.ft.
Tab 0.314 sq.ft.
Fin 4.700 sq.ft.
Rudder 7.250 sq.ft.
Fuel Capacity 24 gal.
Optional Aux Tank (Installed in fwd cpit) 18 gal.
Model Specific Specifications
ST ST-A ST-A Special STM-S2
Powerplant Menasco B-4 Menasco C-4 Menasco C-4S Menasco C-4S
Horsepower 95 hp @2000 125 hp @2175 150 hp @2260 150 hp @2260
Empty Weight 1023 lb 1081 lb 1083 lb 1311 lb
Gross Weight 1575 lb 1600 lb 1600 lb 1828 lb
Useful Load 552 lb 519 lb 517 lb 517 lb
Oil Capacity 2 gal 3 gal 3 gal
Fuel Consumption (75% Power) 7 gph 8 gph 10 gph 10 gph
Power Loading 12.8 lb/hp 10.67 lb/hp 12.18 lb/hp
Wing Loading 12.9 lb/ft^2 12.9 lb/ft^2 14.71 lb/ft^2
Flight Performance
ST ST-A ST-A Special STM-S2
Max Speed Level Flight
Sea Level 126 mph 138 mph 122 mph
3,281 ft 124 mph 142 mph 120 mph
6,562 ft 123 mph 140 mph 118 mph
10,000 ft 118 mph 137 mph 111 mph
13,123 ft 114 mph 134 mph
16,000 ft 108 mph 131 mph
Cruising Speed
Sea Level 113 mph 125 mph 108 mph
3,000 ft 115 mph 128 mph 107 mph
7,600 ft 122 mph
11,500 ft 136 mph
Landing Speed
Power off - Full Load - Sea Level 54 mph 54 mph 59 mph
Range
Gross Weight/Full Fuel
7,600 ft 366 mi.
11,500 ft 326 mi. 246 mi.
Gross Weight/Full fuel+18 gal aux tank 640 mi. 571 mi. 432 mi.
Rate of Climb-Full Power/Gross Weight
Sea Level 800 fpm 975 fpm 700 fpm
10,000 ft 320 fpm 505 fpm 210 fpm
Time to Climb
S.L. to 3,281 ft 3.8 min 4.0 min 5.5 min
S.L. to 6,652 ft 10.5 min 8.25 min 12.5 min
S.L. to 9,842 ft 19.0 min 13.75 min 20.3 min
S.L. to 10,000 ft 19.5 min 14.0 min 24.4 min
S.L. to 13,123 ft 34.0 min 21.25 min 44.0 min
S.L. to 16,000 ft 52.0 min 32.0 min
Service Ceiling (Full Load) 15,500 ft 16,000 ft 18,600 ft 12,250 ft
Absolute Ceiling (Full Load) 17,200 ft 20,800 ft 14,280 ft
Take-off run (ground run) (5 mph wind)
Sea Level 690 ft 680 ft
Landing run with flaps (5 mph wind)
Sea Level 523 ft 523 ft
Landing run without flaps (5 mph wind)
Sea Level 608 ft 608 ft
Powerplant Specifications
Menasco B-4 Menasco C-4 Menasco C-4S
Power 95 hp @2000 125 hp@2175 150 hp @2260
Number of Cylinders 4 4 4
Bore (inches) 4-1/2 4-3/4 4-3/4
Stroke (inches) 5-1/8 5-1/8 5-1/8
Displacement (cubic in) 326 363 363
Compression Ratio 5.5:1 5.5:1 5.5:1
Dry Weight (lb) 285 290 310
The C-4 and C-4S required 73 octane or better fuel.