A further development of the previous Convair 880, the 990 Coronado was built to increase capacity. but this was sadly not enough to make this aircraft competitive against the big boys of the Jet Age.
To understand the 990, you need to look at the 880 off which it is based. The Convair 880 attempted to market speed over capacity when compared to its rivals the Douglas DC-8 and the Boeing 707. Launched in 1989, the aircraft had a claimed top speed of 615mph, making it the fastest jet transport in the world. However, it was an incredibly expensive and incredibly inefficient aircraft to run, which made it nowhere near as popular as its contemporaries. As such, Convair was looking for any way possible to expand its sales.
American Airlines were the ones to first step into the breach with the desire for a stretched version of the Convair 880. While speed was nice, capacity was still very much an important factor, of which the small 880, with its 110 passenger capacity, was severely lacking. As such, Convair were willing to make this alteration so as to marry capacity with speed, primarily for the lucrative coast-to-coast flights. To do this, the aircraft had to be light enough to fly at such speeds, and also have the range to do non-stop flights between New York and Los Angeles, but still be able to carry more passengers than its older brother.
The design of the 990 is essentially the same except for the main fuselage alterations to increase capacity. The fuselage was lengthened by 10ft to increase capacity from 110 to 121, but this was still much less than the likes of the 707 or DC-8. However, Convair once again went back to their original idea of marketing speed over space, and modified the aircraft’s aerodynamics to allow it to fly as close to the Sound Barrier as possible. Large
anti-shock bodies on the upper trailing edge of the wings meant that transonic drag was reduced and the closer the aircraft could get to the speed of sound. The addition of these bodies made room for an extra fuel tank on both wings to make up for the range. Plans were considered to put fuel in the outboard pods as well, but this resulted in the aircraft osculating at certain speeds. This was resolved by shortening them by 28 inches, but this had the detrimental effect of increasing drag again.
However, the biggest party piece for the 990 was the changing of the engines from the 880’s General Electric CJ-805-3B to General Electric CJ805-23B’s. These engines were modified largely from GE J79 powerplants used in jet fighters such as the Starfighter and the Hustler, the main differences being these were non-afterburning. However, these engines were not only very noisy, but produced incredible amounts of smoke, even when idling. While the competitive Pratt & Whitney JT3D engines found on the 707 were also very smoky and noisy, the -23B’s were in a league of their own, probably rivalling that of Concorde and the VC10.
Nevertheless, the plane made it’s first flight on January 24th, 1961, but disappointment was soon to follow success. The 990 failed to meet American’s specifications, and the company reduced its order number. Convair responded by developing the 990A, which was fitted with fairings to the engine nacelles, together with a dozen other minor changes, all of which intended to reduce the drag problems. The noise and inefficiency were also major factors in the aircraft’s failure to become a major hit, especially when you consider that it burnt 13,750 pounds of fuel per hour, while a modern equivalent, the Boeing 757, only burns 7,000 pounds of fuel per hour, and that’s a larger aircraft with a greater capacity. The aircraft’s inefficiency meant that its range was compromised, and the only way the 990 could keep up to its non-stop coast-to-coast routes was by flying
slower, removing the aircraft’s unique selling point. Eventually, the aircraft had to fly so slowly that it barely made any difference when compared to the 707 in terms of timekeeping. As such, American Airlines sold off its last 990’s in 1967, only 6 years after the first ones were introduced.
The 990 did however find more success in Europe, with Swissair buying up eight of the 990A variants in 1962 for flights to the Middle East, the Caribbean, Africa and South America. SAS Scandinavian Airlines also bought up a few for long haul flights to Tokyo and the Far East. However, their inefficiency came back to bite them, and by the mid-70’s they had largely been displaced by their Boeing rivals the 720 and the 727. By 1978, most of the 37 990’s built between 1961 and 1963 had been grounded and put into store, but their useful lives were far from over. In the early 1980’s, Spantax of Spain took on several to operate charter flights within Europe. Spantax had first taken on 990’s in 1967 following their withdrawal from American Airlines, and later took on several more to operate right up until the airline went bankrupt in 1988. Another unit was used by a Denver based private hire company, and was available for rent by celebrities and sports teams until the operation folded in 1992. 990’s also found work with airlines such as Alaska Airlines, VARIG, Thai International, MEA, Garuda Indonesia and Cathay Pacific, but these were mostly for short periods or briefly hired. By the early 1990’s nothing remained of the
fleet, all were either scrapped, grounded or put in museums. The effects of the 990’s failure to sell hit Convair hard, and the company suffered one of the biggest corporate losses in American history. While it, and parent company General Dynamics, would continue to build space-rockets until the Convair brand was dissolved in 1996, the only work it carried out in the aviation industry was as a subcontractor to help produce fuselages for longtime rivals McDonnell Douglas and their DC-10’s.
Despite such a small fleet however, the 990 suffered 9 crashes or incidents throughout its short working life.
- The first was on May 30th, 1963, when an American Airlines 990 was burnt to the ground while parked at Newark International Airport in New Jersey, thankfully with no one aboard.
- The next came five years later on May 28th, 1968, when a 990 operating for Garuda Indonesia crashed almost vertically into the ground shortly after departure from Bombay, killing all 29 aboard and one person on the ground.
- Two years later, and on January 5th, 1970, a Spantax 990 crashed at Stockholm while operating a ferry flight to Zurich, killing 5 of the 10 people aboard.
- The same year on February 21st, Swissair Flight 330 crashed near Wurenlingen in Switzerland after a bomb was detonated in the aft cargo hold, killing all 47 aboard.
- Also in 1970, on August 8th, a Modern Air Transport 990 crashed on approach to Alvarez International Airport in Mexico, killing 1 of the 8 aboard.
- On December 3rd, 1972, Spantax Flight 275 overshot the runway while taking off from the infamous Tenerife Los Rodeos Airport, killing all 155 aboard.
- The aircraft has also suffered two mid-air collisions; the first being on March 5th, 1973, over Nantes in France, when Spantax Flight 400, a 990, struck Iberia Flight 504, a DC-9. The 990 lost part of its left wing but was able to limp to a nearby airbase, the DC-9 on the other hand crashed, resulting in the deaths of all 68 aboard.
- This was followed the same year on April 12th, when a NASA owned 990 crashed into a Lockheed P-3C on the runway at Moffett Field in California, killing all but one aboard both aircraft.
- The final crash of a 990 took place on July 17th, 1985, when a NASA owned aircraft suffered a blown out tire during takeoff, resulting in it overshooting the runway and catching fire. Thankfully, all aboard were able to escape before the aircraft burnt to cinders.
However, today there are 6 known 990’s that still survive in varying degrees of
preservation. 3 are in America, one is in Spain, one is in Majorca and one is in Switzerland.
So, the Convair 990? Was it one of the worst aeronautical failures ever?
That, sadly, can’t be denied, it only ever sold 37 units, most of which were retired after 5 to 10 years, and only saw real service on the second-hand market. There’s a good aircraft idea behind the 990, putting speed over capacity later became something of a desire among aircraft manufacturers, as was the case with Concorde. However, the 990 was not a supersonic airliner, it was just a very noisy, very small and very inefficient jet airliner that failed to cover its losses. It couldn’t reach its potential, and for that it suffered heavily in sales.