Hawker Siddley HS.748
Beginning as an A. V. Roe project in 1958, the original Type 748 was planned as a 20-seat short/medium-range feeder airliner. When no interest was shown in the design, it was scaled up in size and the Hawker Siddeley Group, of which Avro was a component company, decided to put the aircraft into production.
The first flight of the prototype took place at Woodford on 24 June 1960. The first production aircraft, capable of seating a maximum of 48 passengers, was designated Avro 748 Series 1. It first flew on 31 August 1961, powered by two 1298kW Rolls-Royce Dart 514 turboprops.
This aircraft has a takeoff run of only 2,750 feet, for STOL performance it has a long-span wing, mounted low, with Fowler flaps driven by an electric actuator. The Rolls-Royce Dart turboprops, mounted with their jet pipes above the wings, are rated at about 2,280 hp, though some military versions have 3,200-hp Darts. Most civil versions of the HS 748 seat 40 to 58 passengers and some are equipped for freight or passenger/freight operations.
Redesignated HS.748 in 1963, later versions included the Series 2 and Series 2A (1967) civil transports; Andover CC.Mk 1 and CC.Mk 2 for the RAF, the CC.Mk 2 being two specially equipped examples for The Queen's Flight; the Coastguarder variant was also developed, optimised for maritime patrol, flying in 1977.
Hawker Siddeley Andover C.1
The 748-2B incorporated a 2000 lb increase in payload, increased span, more powerful engines, and a number of cockpit refinements, flew in June 1979.
A production version of the twin-turboprop transport is the Super 748. In its Military Transport form the 748 has a large rear freight door, strengthened floor, and optional military overload take-off and landing weights giving improved payload/range capabilities.
Outwardly, the 748 is similar to the 780 Andover aircraft which differ mainly in having more powerful engines (and reverse pitch propellors), a rear loading ramp, and a kneeling undercarriage. Only 31 Andovers were built, along with six of the Andover CC.2 version of the civil 748. Although developed from the basic Hawker Siddeley 748 and retaining it’s exterior looks, with the exception of the revised tail and straight-in loading ramp, the Andover does have only 20 per cent commonality with the 748. The Andover’s “kneeling” undercarriage allows the aircraft’s fuselage to be lowered to allow easier loading and unloading. The STOL performance for a 42,000 lbs take off, the Andover requires 1,300 ft (to 50 ft), while 1,340 ft is needed for a short field landing (from 50 ft) at 40,000 lbs auw. Reverse-thrust propellors assists the short field performance.
Production of all versions, including 79 assembed in India by Hindustan Aircraft from parts man-ufactured in both countries, totalled 380 aircraft.
Engines: 2 x Rolls-Royce Dart, 2280 shp.
Wing span: 98 ft 6 in (15.24 m).
Length: 67 ft 0 in (20.42 m).
Height: 24 ft 10 in (3.51 m).
Max TO wt: 44,495 lb (20182 kg).
Max level speed: 278 mph (448 kph).
Engines: 2 x Rolls-Royce Dart 7 Mk.535-2, 1,835 shp.
Props: Dowty-Rotol 4-blade, 144-in.
Length: 67 ft.
Height: 24.8 ft.
Wingspan: 102.5 ft.
Wing area: 829 sq.ft.
Wing aspect ratio: 12.7.
Maximum ramp weight: 46,700 lbs.
Maximum takeoff weight: 46,500 lbs.
Standard empty weight: 26,650 lbs.
Maximum useful load: 20,050 lbs.
Maximum landing weight: 43,000 lbs.
Wing loading: 56.1 lbs/sq.ft.
Power loading: 12.7 lbs/hp.
Maximum usable fuel: 11,200 lbs.
Best rate of climb: 1470 fpm.
Service ceiling: 25,000 ft.
Max pressurisation differential: 5.5 psi.
8000 ft cabin alt @: 25,000 ft.
Maximum single-engine rate of climb: 359 fpm.
Single-engine ceiling: 10,700 ft.
Maximum speed: 250 kts.
Normal cruise @ 25,000ft: 230 kts.
Fuel flow @ normal cruise: 1257 pph.
Endurance at normal cruise: 8.4 hrs:
Stalling speed clean: 95 kts.
Stalling speed gear/flaps down: 71 kts.
Turbulent-air penetration speed: 155 kts.
HS 748 series 2B
Engines: 2 x Rolls-Royce Dart Mk 555, 1700kW
Take-off weight: 23133 kg / 51000 lb
Empty weight: 11644 kg / 25671 lb
Wingspan: 31.23 m / 102 ft 6 in
Length: 20.42 m / 66 ft 12 in
Height: 7.57 m / 24 ft 10 in
Wing area: 77.0 sq.m / 828.82 sq ft
Cruise speed: 452 km/h / 281 mph
Ceiling: 7620 m / 25000 ft
Range w/max.payload: 1307 km / 812 miles
Engine: 2 x R-R Dart turboprop, 3400 kW.
Span: 31.2 m.
Length: 20.4 m.
Wing area: 77 sq.m.
Empty wt: 11,700 kg.
MTOW: 23,100 kg.
Payload: 5800 kg.
Cruise speed: 455 kph.
Initial ROC: 430 m / min.
Ceiling: 7600 m.
T/O run: 1082 m.
Ldg run: 387 m.
Fuel internal: 6550 lt.
Range/payload: 1865 km with 5800 kg.
Capacity: 60 pax.
748MF Andover C.1
Engines: 2 x RR Dart 12 Mk 201C, 3,000 shp.
MTOW: 50,000 lbs.
Fuel cap: 1,440 Imp gallons, + 860 gallons in an integral centre-wing tank.
Range: 1,020 nm (1,800 nm with 860 Imp aux).
Pax cap: 57 passengers (at 30” pitch).
Cruise alt: 20,000 ft.
Max speed: 302 mph @ 15,000 ft.
Service ceiling: 23,800 ft.
Maximum payload: 14,750 lbs.
Take off distance mauw: 3810 ft.
Landing ground roll max ldg wt (47,600 lbs): 2490 ft.
Engines: 2 x Rolls-Royce Dart 12 Mk.201, 3425 shp.
Max payload: 6270 kg.
Hawker Siddeley Andover C Mk 1
Engine: 2 x Rolls Royce Dart R.Da 12 Mk. 210 C, 2929 shp
Length: 77.92 ft / 23.75 m
Height: 30.085 ft / 9.17 m
Wingspan: 98.261 ft / 29.95 m
Max. speed: 262 kts / 485 km/h
Service ceiling: 24016 ft / 7320 m
Range: 1031 nm / 1909 km
748-2A Andover CC2
Engines: 2 x RR RDa7 Dart 152, 2280 shp.
TBO: 1600 hr.
Max cruise: 245 mph.
Econ cruise: 243 mph.
Stall: 82 mph.
Fuel cap: 11628 lb.
Fuel flow max cruise: 1850 pph.
Fuel flow econ cruise: 1400 pph.
Service ceiling: 23,000 ft.
SE service ceiling: 13,000 ft.
ROC: 1300 fpm.
SE ROC: 750 fpm.
Min balanced field length: 4050 ft.
Payload with full fuel: 8790 lb.
Max range: 1828 mile.
High speed range: 1068 mile.
Max payload: 16,773 lb.
Range with max payload: 761 mile.
Pressurisation differential: 5.5 lb.
Gross wt: 46,500 lb.
Empty wt: 29,727 lb.
Useful load: 16,773 lb.