Development of the Convair 990 began when the company lost a vital United Airlines order for 30 aircraft. To attract American Airlines, Convair designed an aircraft with transcontinental range and higher speed and on 30 July 1958 Convair announced the Model 30. This was a natural growth version of the 880 and used a turbofan of 16,050 lb. Originally known simply as the Convair 880M, the new aircraft was much more than a ‘slight modification’ contrary to what the General Dynamics’ board was told. The new variant used a redesigned engine (the CJ 805 23), with a rear mounted fan and a higher bypass ratio. This required a new engine nacelle, while the need to reduce drag led to the addition of Whitcomb bodies on the wing trailing edge to ‘area rule’ the aircraft. The new aircraft also included a new proportional anti skid system, a modified undercarriage and a hydraulically powered rudder. The rest of the aircraft was strengthened to accommodate much more fuel, and the fuselage was stretched 10 ft to house 106 passengers (foreign customers later fitted in over 140) and the tailplane was increased in area.
Howard Hughes initially refused to allow Convair to give the new aircraft a designator ‘higher’ than 880, so the new aircraft was instead initially known as the Convair 600. Convair guaranteed a speed of 550kts (1021 km/h) (agreeing to financial penalties if it failed to deliver) and charged American only $100m for its 25 aircraft (later reduced to 20), taking $22.8m of the money in the form of 25 over valued DC 7s (worth $10m at most). Swissair converted its order for five 880s to an order for seven 990s. The Convair 990 originally failed to meet its guaranteed performance and the prices to American and Swissair were reduced. The airlines initially operated their aircraft without making progress or engine payments while Convair sorted out the problems. The problems were solved in the Convair 990A, but Convair’s chance to dominate the jetliner market vanished when Boeing re engined its 707s with Pratt & Whitney’s new JT3D turbofan, which could be produced by conversion of existing JT3C engines. Thus the fan engined 990 lost its unique selling point. Swissair and American began scheduled revenue services during March 1962. Other Convair 990 operators included Aerolineas Peruanas, Garuda, SAS, Thai International Airways and VARIG.
Models built for Swissair and VARIG differed slightly from standard 990s. Powered by CJ 805 23B engines, they carried slightly more fuel and had higher operating weights. They were officially known as Coronados, a name later used to describe all Convair 990s.
The announcement of the new jet was accompanied by a launch order for 20 from American Air¬lines. The aircraft was renamed Convair 990. The first off the production line flew on 24 January 1961, and by this time the programme was in deep trouble. Drag was well overestimate, and it took two years of extremely costly modifications to get near the guaranteed performance.
In addition to four large anti¬shock bodies above the trailing edge (sometimes called Küche¬mann carrots, these also served as fuel tanks) Kruger flaps were added under the wing and a com¬plex series of extensions, bumps and fairings added to the engine pods and pylons. The aircraft’s long range came about by using the four wing pods as fuel tanks. The 24-foot-long pods, known as “antishock bodies,” reduce the intensity of shock waves generated when an airplane reaches the speed of sound. In essence, they control the air flowing over the wing and therefore reduce drag. Payload, at 26,440 lb, was widely considered inadequate. The cabin was criti¬cised, as were the lack of customer options, and in the end, in addition to the launch order, only 17 aircraft were sold. American accepted the first (unmodified) 990 on 8 January 1963, and fully modified 990As en¬tered service late that year.
Lebanese International Airways and MEA operated Coronados during the late 1960s and early 1970s. LIA went into liquidation after its two Coronados were destroyed on the ground by Israeli commandos in 1968, while MEA phased out its aircraft in favour of Boeing 707s and 720s in 1972.
Following their retirement from major airlines, many Coronados found employment with travel clubs and minor airlines. Modern Air Transport obtained eight Convair 990s between January 4, 1967 and January 1971 and operated these primarily on charter work. These were often unorthodox, including polar flights landing at McMurdo Sound (the first commercial jets to do so) and even a unique 1970 Father’s Day ‘Get Away from Mama’ Busenvogel (Bosom flight) from Berlin to Paris and back, in which the stewardesses wore uniforms with transparent bodices. The company fitted new slim line seats which allowed capacity to increase to 149, without reducing leg room.
The last major operator of the Coronado was the Spanish charter airline Spantax. Spantax delib¬erately collected used examples and retired the last of 14 aircraft in March 1987. One Spantax 990 survived a mid air collision with a DC 9 over France. Ten of the surviving airframes were scrapped at Palma between 1991 and 1993, but one was retained for preservation.
In 1988 an ex Ports of Call 990 was sold to Ciskei International Airways, but this flew only a single pre inaugural flight when it could not acquire the necessary permits. The aircraft was eventually ferried to EI Paso in 1991.
NASA had been a long term operator of the Coronado, using a succession of three aircraft for atmospheric, astronomical, meteorological and solar experiments and support duties. The final aircraft was reactivated in 1980 for three years, then again in 1988 for use as a landing systems research aircraft, testing the Space Shuttle undercarriage to expand the vehicle’s landing envelope and to allow increased use of the landing site at the Kennedy Space Center Every time a Shuttle landed at Edwards, it required a piggy back ride back to Kennedy atop a Boeing 747, costing $1m per time, all because Kennedy might have been just outside the Shuttle’s crosswind limits. The tests encompassed 155 test flights ending in August 1995. Two CV 990s remained in store at Mojave.
990 Coronado
Engines: 4 x General Electric turbofan, 16,050 lb.
Cruising speed 494kts (917km/h) at 35,000ft (10,668m).
Range 7,741km (4,172nm).
Weight empty 54,686kg (120,560 lb).
Gross weight 115,668kg (255,000 lb).
Payload: 26,440 lbs.
Span 36.5m (120ft 0in).
Length 42.49m (139ft 5in).
Wing area 209sq.m (2,250 sq.ft).
Pax cap: 104-140.
990A
Engine : 4 x General Electric CJ-805-23B, 71613 N / 7300 kp
Wing span: 120 ft 0 in (36.58 m).
Length: 139 ft 5 in (42.5 m).
Height: 39 ft 6 in (12.04 m).
Max TO wt: 244,200 lb (110,765 kg).
Max level speed: 540 kts / 625 mph (1006 kph).
Service ceiling : 41011 ft / 12500 m
Range : 2646 nm / 4900 km
Crew : 9+116
