The design of the Lockheed L-188 Electra began in 1954, and in the following year the company received a launching order from American Airlines.
By the first flight, 144 were already on order. The prototype, first flown on 6 December 1957, was a low-wing monoplane of conventional configuration with retractable tricycle landing gear and powered by four Allison 501D-13, 501D-13A or 501D-15 turboprop engines. Standard accommodation was for 66 to 80 passengers, but a high-density arrangement was available optionally to seat 98.
Several crashes occurred in 1959 that caused Lockheed Corp. to make a few improvements including a stronger wing structure and engine nacelles plus thicker wing skins.
Built initially as the L-188A, the Electra became available also as the longer-range L-188C with increased fuel capacity and operating at a higher gross weight. A total of 170 had been built when production ended unexpectedly early as a result of passenger loss of confidence in the type after two had disintegrated in flight, and by the time remedial modifications had been, incorporated customer airlines were interested in turbojet- rather than turboprop-powered aircraft. About half of the total built remained in service in 1992, many of them converted by Lockheed Aircraft Service for convertible passenger/cargo or all-cargo use.
L-188A Electra
Engines: 4 x Allison 501D-13, 2796kW / 4600 hp
Propellers: Hamilton Standard
Max take-off weight: 51256 kg / 113001 lb
Empty weight: 26036 kg / 57400 lb
Wingspan: 30.18 m / 99 ft 0 in
Length: 31.85 m / 104 ft 6 in
Height: 10.01 m / 32 ft 10 in
Wing area: 120.77 sq.m / 1299.96 sq ft
Cruise speed: 652 km/h / 405 mph
Ceiling: 8655 m / 28400 ft
Range: 3541 km / 2200 miles
Crew: 5
Passengers: 44-98
Engines: 4 x 4,050 h.p. Allison 501 D15 turboprop.
Length 104.5 ft. (31.81 m.)
Wing span 99 ft. (30.18 m.)
Weight empty 57,300 lb. (25,990 kg.)
MTOW: 113,000 lbs (51,227 kg).
Pax cap: 99.
Max cruise 405 m.p.h. (650 km.p.h.)
Ceiling 28,400 ft. (8,655 m.)
Range 2,770 miles (4,458 km.) with 18,000 lb. (8,165 kg.) payload
Cabin width: 10 ft 8 in.
Takeoff run 4,720 ft
Landing roll 4,300 ft
All Aero 