Percival P.40 Prentice Single-engine three-seat low-wing monoplane trainer

Percival P.40 Prentice
Single-engine three-seat low-wing monoplane trainer

Archive Photos ¹

Overview ²

Role: Military trainer aircraft
Manufacturer: Percival Aircraft, Ltd.
First flight: 31 March 1946
Introduction: November 1947
Retired: 1953
Primary users: Royal Air Force; private pilot owners after disposal by the RAF
Produced: 1947-1949
Number built: >370

The Percival Prentice three-seat trainer was designed to Specification T.23/43. The first prototype flew early on 31 March 1946. As a result of flying trials, a number of modifications were incorporated in the design of the production aircraft, including upturned wing-tips, re-designed control surfaces, and provision for an anti-spin extension to the tailplane.

The Prentice was to be fitted with either the 250-hp DH Gypsy Queen 32 or the 296-hp Gypsy Queen 51 engine. The Prentice was produced by Percival Aircraft, and by Blackburn Aircraft, Ltd. at Brough, and by Hindustan Aircraft, Ltd. at Bangalore, India.

Specification and Performance ²

Manufacturer

Percival Aircraft, Ltd., Luton Airport, Luton, Bedfordshire, England

Type

Three-Seat Basic Trainer

Wings

All-metal cantilever low-wing monoplane.
Wing section R.A.F. 48.
Aspect ratio 6.94
Dihedral (front spar) 3° 24’.
Two-spar structure built into sections attached direct to fuselage.
Detachable wingtips.
Spars have light extruded flanges and reinforced plate webs.
Leading and trailing-each portions made up as complete units.
Full-depth pressed light alloy ribs approximately 20 inches (50.8 cm) apart with three light former ribs top and bottom between.
Light alloy steel covering.
Reinforced root has span-wise stringers to form walkway.
Ailerons have light alloy D-spar, pressed sheet ribs and fabric covering.
Trim-tab in port aileron adjustable on ground only.
Pneumatically-operated split trailing edge flaps and three sections between ailerons.
Safety device prevents immediate retraction of flaps after baulked landing.
Gross wing area 305 ft² (28.3 m²).
Aileron area (total) 24 ft² (2.23 m²).

Fuselage

All-metal structure in two portions, front portion of rectangular section to aft of cockpit, and rear portion of flattened elliptical section.
Front portion has sides and bottom built up as a semi-braced structure with light alloy sheet covering.
Two build-up girders across fuselage form attachments for main wing spars.
Rear portion is a semi-monocoque structure with light alloy frames, longitudinal stringers and light alloy sheet covering.
Maximum fuselage with 4 feet 2 inches (1.27 m).

Tail Unit

All-metal cantilever structure.
Tailplane has two light alloy stars, pressed sheet ribs and stressed metal skin, and is bolted to fuselage.
Two-spar fin with main spar bolted to fuselage sternpost.
Elevators have light-alloy D-spar, pressed sheet ribs and fabric covering.
Rudder of similar construction with metal covering and with mass balance in horn-balanced portion.
Controllable trim-tabs and rudder and elevators.
Area of tailplane and elevators, 57.34 ft² (5.32 m²).
Area of fin 21.3 ft² (1.97 m²).
Area of rudder 18 ft² (1.67 m²).

Landing Gear

Fixed two-wheel divided type.
Each unit consists of cantilever shock-absorber leg incorporating steel springs and oleo damper, and is bolted to casting on front face of main spar.
Streamlined fairing over leg and wheel.
Medium-pressure wheels.
Pneumatic brakes operated by rudder-bar.
Track 12 feet 0 inches (33.65 m).
Tail-wheel carried in full-swiveling self-centering fork which rotates in cast aluminum rocker-arm hinged at bottom of sternpost.
Steel-spring shock-absorption with Ferodo band recoil-damper.

Power Plant

One 250-hp DH Gypsy Queen 32 un-supercharged, or 296-hp Gypsy Queen 51 supercharged, six-cylinder in-line inverted air-cooled engine on rubber anti-vibration blocks of steel-tube mounting.
De Havilland two-blade constant-speed airscrew.
Cowling in four parts, side panels hinged on top centerline.
Two 20 Imperial gallon (91 liters) crash-proof fuel tanks in wing-roots between spars with detachable access panels in undersurface of wing.
Oil tank of 4.9 Imperial gallons (22 liters) capacity in leading-edge of port wing root with oil-cooler inboard.

Accommodation

Crew of three and ventilated and heated enclosed cockpit.
Pilot (on starboard) and pupil, side-by-side with dual controls in front, with third central seat for second pupil undergoing air experience behind.
Standard S.B.A.C seats, front two adjustable.
Entire cabin top made as complete unit and bolted to fuselage structure.
Forward portion has direct-vision safety-class windscreen.
Perspex hood sides Backward for access.
Side and top panels amber-tinted.
Front windscreen and forward half of lower panel in sliding hood fitted with folding amber-colored screens for night instruction.
Rear seat entered through upward sliding door on port.
Steel-tube crash-pylon between front and rear seats.
Cabin sides from front arch to front of rear door jettisonable.

Dimensions

Span: 46 feet 0 inches (14.02 m)
Length: 31 feet 3 inches (9.52 m)
Height (tail up, over rudder): 12 feet 10½ inches (3.9 m)

Weights (Non-Aerobatic)

Weight empty: 3,080 lbs (1398.3 kg)
Fuel: 280 lbs (130.7 kg)
Oil: 40 lbs (18.2 kg)
Radio: 24 lbs (10.9 kg)
Crew (3): 600 lbs (272.4 kg)
Equipment: 18 lbs (18.2 kg)
Weight loaded: 4,650 lbs (1,838.7 kg)

Weights (Aerobatic)

Weight empty: 3,080 lbs (1398.3 kg)
Fuel: 280 lbs (130.7 kg)
Oil: 40 lbs (18.2 kg)
Radio: 24 lbs (10.9 kg)
Crew (2): 400 lbs (181.6 kg)
Equipment: 18 lbs (18.2 kg)
Weight loaded: 3,850 lbs (1,748 kg)

Performance (DH Gypsy Queen 32 engine)

Maximum speed at sea level: 150 mph (242 km/h)
Maximum speed at 5,000 feet (1,525 m): 146 mph (235 km/h
Maximum continuous cruising speed at 2,200 feet (670 m): 145 mph (234 km/h)
Maximum economical cruising speed at 3,500 feet (1,066 m): 140 mph (225 km/h)
Stalling speed (flaps up): 61.5 mph (99 km/h)
Stalling speed (flaps down): 56.3 mph (90.6 km/h)
Initial rate of climb: 700 ft/min (213 m/min)
Rate of climb at 5,000 feet (1,525 m): 500 ft/min (152 m/min)
Climb to 5,000 feet (1,525 m): 8.3 minutes.
Service ceiling: 15,000 feet (4,575 m)
Takeoff run to clear 50 foot (15.25 m) from grass: 390 yards (357 m)
Takeoff run to clear 50 foot (15.25 m) from concrete: 365 yards (334 m)
Range at 5,000 feet (1,525 m) at 138 mph (222 km/h): 485 miles (780 km)

Performance (DH Gypsy Queen 51 engine)

Maximum speed at sea level: 150 mph (241 km/h)
Maximum speed at 6,800 feet (2,0872 m): 168 mph (270 km/h
Maximum continuous cruising speed at 5,400 feet (1,945 m): 156 mph (251 km/h)
Maximum economical cruising speed at 12,200 feet (3,718 m): 155 mph (249 km/h)
Stalling speed (flaps up): 61.9 mph (100 km/h)
Stalling speed (flaps down): 56.6 mph (91 km/h)
Rate of climb at sea level: 9200 ft/min (280 m/min)
Rate of climb at 5,000 feet (1,525 m): 700 ft/min (213 m/min)
Climb to 5,000 feet (1,525 m): 7.1 minutes.
Service ceiling: 18,520 feet (5,640 m)
Takeoff run to clear 50 foot (15.25 m) from grass (tropical summer temperature): 420 yards (394 m)
Takeoff run to clear 50 foot (15.25 m) from grass (normal temperature, at 5,000 feet=1,525 m): 390 yards (357 m)
Takeoff run to clear 50 foot (15.25 m) from concrete (normal temperature, at 5,000 feet=1,525 m): 360 yards (339 m)
Takeoff run to clear 50 foot (15.25 m) from grass (tropical summer temperature, at 5,000 feet=1,525 m): 435 yards (398 m)
Takeoff run to clear 50 foot (15.25 m) from concrete (tropical summer temperature, at 5,000 feet=1,525 m): 405 yards (370 m)
Range at 5,000 feet (1,525 m) at 5,000 feet (1,525 m) at 139 mph (224 km/h): 517 miles (832 km)

References

Photos: John Shupek
Bridgman, Leonard, Jane’s All The World’s Aircraft 1948, Sampson Low, Marston & Company, Ltd., London, 1948, pp. 83c-84c