Piper PA-31 Navajo

https://en.wikipedia.org/wiki/Piper_PA-31_Navajo

The Piper PA-31 Navajo is a family of cabin-class, twin-engined aircraft
designed and built by Piper Aircraft for the general aviation market, most using
Lycoming engines. It was also license-built in a number of Latin American
countries. Targeted at small-scale cargo and feeder liner operations and the
corporate market, the aircraft was a success. It continues to prove a popular
choice, but due to greatly decreased demand across the general aviation sector
in the 1980s, production of the PA-31 ceased in 1984.

At the request of company founder William T. Piper, Piper began development of a
six- to eight-seat twin-engined corporate and commuter transport aircraft in
1962 under the project name Inca. The type, now designated the PA-31 and looking
like a scaled-up Twin Comanche, was officially announced in late 1964 after its
first flight on 30 September that year. It was a low-wing monoplane with a
conventional tail, powered by two 310 hp (231 kW) Lycoming TIO-540-A
turbocharged engines in so-called "tiger shark" cowlings, a feature shared with
the Twin Comanche and also the PA-23 Aztec. As testing proceeded two cabin
windows were added to each side of the fuselage and the engines moved further
forward. The PA-31, now named "Navajo" after a Native American tribe, was not
certified by the Federal Aviation Administration (FAA) until 24 February 1966,
and deliveries did not begin until the following year, after the type was
recertified in mid-1966 with an increase in maximum takeoff weight (MTOW) from
6,200 lb (2,812 kg) to 6,500 lb (2,948 kg).

The PA-31-300 was the next model, certified by the FAA in June 1967. This model
was the only one of the PA-31 series not to have turbocharged engines. A pair of
300 hp (224 kW) Lycoming IO-540-M1A5 engines were fitted to the PA-31-300,
driving two-bladed propellers. Following the introduction of the PA-31-300 the
turbocharged model began to be known unofficially as the PA-31-310. The
PA-31-300 was only produced in 1968 and 1969 and had the smallest production
total for any PA-31 series model, with only 14 aircraft built.


Role
Civil utility aircraft

Manufacturer
Piper Aircraft

First flight
30 September 1964

Introduction
30 March 1967

Status
Active service

Produced
1967–1984

Number built
3942

Variants
Piper PA-31T Cheyenne

The PA-31 series was manufactured under licence in several countries from kits
of parts supplied by Piper. Chincul SACAIFI in Argentina assembled most of the
series as the PA-A-31, PA-A-31-325, PA-A-31P and PA-A-31-350 and Aero Industrial
Colombiana SA (AICSA) in Colombia assembled PA-31, PA-31-325 and PA-31-350
aircraft. The PA-31-350 Chieftain was also assembled under licence in Brazil by
Embraer as the EMB 820C Navajo. In 1984, Embraer subsidiary company Indústria
Aeronáutica Neiva began converting Embraer EMB 820Cs by installing Pratt &
Whitney Canada PT6 turboprop engines; Neiva called the converted aircraft the
Carajá.

Specifications (PA-31 Navajo)

General characteristics
Crew: one or two
Capacity: five to seven passengers
Length: 32 ft 7½ in (9.94 m)
Wingspan: 40 ft 8 in (12.40 m)
Height: 13 ft 0 in (3.96 m)
Wing area: 229 sq. ft (21.3 m²)
Empty weight: 3,930 lb (1,782 kg)
Max. takeoff weight: 6,500 lb (2,948 kg)
Powerplant: 2 × Lycoming TIO-540-A air-cooled six-cylinder horizontally opposed
piston engine, 310 hp (231 kW) each
Propellers: Two or three blade, metal, fully feathering, Hartzell propeller

Performance
Never exceed speed: 236 knots (438 km/h (272 mph))
Maximum speed: 227 knots (420 km/h (260 mph)) at 15,000 ft (4,600 m)
Cruise speed: 207 knots (383 km/h (238 mph)) econ cruise at 20,000 ft (6,100 m)
Stall speed: 63.5 knots (118 km/h (73 mph)) flaps down
Range: 1,011 nmi (1,875 km (1,165 mi))
Service ceiling: 26,300 ft (8,015 m)
Rate of climb: 1,445 ft/min (7.3 m/s)




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