12th of August 1978
It was on this day in aviation history that the first production Pilatus PC-7 made its first flight.
In the 1960s development of a training aircraft started with a prototype Pilatus P-3 being modified to what become the Pilatus PC-7 engine configuration by replacing the Lycoming O-435 piston engine with a P&W PT6-A20 engine. The PT6 powered Pilatus P-3 made its first flight in April 1966. However, a combination of a serious accident with the aircraft and a lack of market interest made Pilatus decide to stop the development.
In 1973 the project was restarted.
Another P-3 was purchased (from the Swiss Air Force) after being fitted with a P&W PT6 engine this second prototype made its first flight in May 1975. After further extensive modifications the P-3, for all intents and purpose, now a PC-7 was used to complete the flight test program which was concluded in late 1977. The modifications (amongst others) consisted of:
Integral fuel tanks
Redesigned tail fin
With the test program ended all efforts went into the production of the PC-7, which led to the first flight on this date in 1978 of the first production aircraft. To this date over 600 PC-7’s have been built. Since that first flight, the PC-7 has been in three versions
PC-7 The basic two-seat trainer powered by a 550 shp P&W PT6A-25A engine
PC-7 Mk II A hybrid aircraft, combining the PC-9’s airframe and avionics with the PC-7 wing (with mounts for external stores) and powered by a P&W PT6A25C engine (700 shp). The aircraft was developed for the South African Air Force and is known as the “Astra”.
NCPC-7 Is a standard PC-7 upgraded with full IFR Glass Cockpit and related avionics. NCPC0-7 was used by the Swiss Air Force to differentiate between upgraded aircraft (with the new avionics) and standard aircraft. Once all aircraft were upgraded all aircraft were designated PC-7 again, losing the “NC” pre-fix.
PC-7 Mk II
Specifications of the PC-7
Crew: two, student and instructor
Length: 9.78 m (32 ft 1 in)
Wingspan: 10.40 m (34 ft 1 in)
Height: 3.21 m (10 ft 6 in)
Wing area: 16.60 m2 (178.7 sq ft)
Aspect ratio: 6.5:1
Empty weight: 1,330 kg (2,932 lb)
Max takeoff weight: 2,700 kg (5,952 lb)
Fuel capacity: 474 L (104 imp gal; 125 US gal) usable internal fuel
Powerplant: 1 × Pratt & Whitney Canada PT6A-25A turboprop, 410 kW (550 shp) (derated from 480 kW (650 shp))
Propellers: 3-bladed Hartzell HC-B3TN-2/T10173C-8 constant-speed propeller, 2.36 m (7 ft 9 in) diameter
Maximum speed: 412 km/h (256 mph, 222 kn) (max cruise at 6,100 m (20,000 ft))
Cruise speed: 171 km/h (106 mph, 92 kn) (econ. cruise at 6,100 m (20,000 ft))
Stall speed: 119 km/h (74 mph, 64 kn) (flaps and gear down, power off)
Vmo : 270 knots (500 km/h - 310 mph,
Range: 2,630 km (1,630 mi, 1,420 nmi) (cruise power, at 5,000 m (16,000 ft) - 20 min reserves)
Endurance: 3 hr 45 min
Service ceiling: 10,000 m (33,000 ft)
Rate of climb: 10.9 m/s (2,150 ft/min
Hardpoints: 6 × hardpoints for bombs and rockets with a capacity of 1,040 kg (2,294 lb)