With its fairly high power-to-weight ratio, huge propellers and very short wings (resulting in the majority of the wingspan being enveloped in propwash), large Fowler flaps which significantly increased effective wing area when extended, and four-engined design, the airplane had airfield performance capabilities unmatched by many jet transport aircraft even today—particularly on short runways and high altitude airfields.
[citation needed] Initial sales were good, but after two fatal crashes that led to expensive modifications to fix a design defect, no more were ordered.
By mid-20th century, Lockheed had established a strong position in commercial airliner production with its piston-engined Constellation series.
The following year, American Airlines revised its requirement to a four-engine design for 75 passengers with 2,000 miles (3,200 km) range.
[4] The CL-310 design met the American Airlines requirements, but failed to meet those of another interested carrier, Eastern Air Lines.
Its requirements were for a longer range, a minimum cruising speed of 350 miles per hour (560 km/h), and increased seating capacity to the 85-to-90-passenger level.
[8][9] The changes were incorporated on the production line by mid-1959 or as modification kits for the aircraft already built, and resulted in improved performance and a better ride for passengers.
The mounting of the gearbox cracked, and the reduced rigidity enabled a phenomenon called "whirl mode flutter" (analogous to the precession of a child's spinning top as it slows down, an interaction of propellers with airflow) that affected the outboard engine nacelles.
In the South Pacific, Tasman Empire Airways Limited (TEAL) and its successor Air New Zealand flew the Electra on trans-Tasman flights.
Most notably, Brazilian flag carrier airline Varig operated flawlessly a fleet of 14 Electras on the extremely busy Rio de Janeiro-São Paulo shuttle service (the so-called Ponte Aérea – or "Air Bridge" in Portuguese) for 30 years, completing over half a million flights on the route before the type was replaced by Boeing 737-300 and Fokker 100 jets in 1992.
[19] The Electra became so iconic on that route that its retirement caused a commotion in Brazil, with extensive press coverage and many special tributes.
Others were retired from passenger service into air-cargo use, 40 being modified by a subsidiary of Lockheed from 1968 with one or two large doors in the left side of the fuselage and a reinforced cabin floor.
[8] Air California and Pacific Southwest Airlines (PSA) were still operating Electras for scheduled passenger service during the late 1970s primarily into the Lake Tahoe Airport located in the Sierra Nevada mountains of California, as this airfield had banned scheduled jet aircraft flights at the time.
These were used during the "Dirty War" to toss political prisoners into the Rio de La Plata in the infamous death flights.
In 1983, after the retirement of its last SP-2H Neptune, the Argentine Navy bought further civilian Electra airframes, modified several for maritime patrol,[23] and widely used them until their replacement by P-3s in 1994.