zippyjet From United States of America, joined Sep 2001, 5746 posts, RR: 12 Posted (4 years 4 months 2 weeks 6 days 18 hours ago) and read 3407 times:
Though billed as the fastest jet in the world back in the day, the Convair 880/990 never really took off sales wise. Another what if thread; What if these 2 Convair Jets were twins instead of 4 holers? Same performance, same size, same capacity etc. Could it have given the 707/720 and DC-8's some formidable competition? How would this have impacted the 727 and 737 programs?
polot From United States of America, joined Jul 2011, 4307 posts, RR: 1
Reply 1, posted (4 years 4 months 2 weeks 6 days 18 hours ago) and read 3359 times:
Quoting zippyjet (Thread starter): Same performance, same size, same capacity etc. Could it have given the 707/720 and DC-8's some formidable competition? How would this have impacted the 727 and 737 programs?
How would it have the same performance (I assume you mean in range/speed and not fuel burn), same size, and same capacity etc while being a twin? The technology just wasn't there. If it existed it probably would give the 707/DC-8 formidable competition...it would be incredibly advanced compared to them.
YXwatcherMKE From United States of America, joined May 2007, 1078 posts, RR: 2
Reply 4, posted (4 years 4 months 2 weeks 6 days 17 hours ago) and read 3260 times:
There is one big problem with you idea! The technology of the day just was not there yet for an aircraft of it's size and performance to produce an engine strong enough to fly the a/c with only two engines. Had there been such an engine back then, then yes, they would not been able to keep up with the demand for them.
I miss the 60's & 70's when you felt like a guest on the plane not cattle like today
Navigator From Sweden, joined Jul 2001, 1422 posts, RR: 13
Reply 8, posted (4 years 4 months 2 weeks 5 days 12 hours ago) and read 2689 times:
Quoting zippyjet (Thread starter): Though billed as the fastest jet in the world back in the day, the Convair 880/990 never really took off sales wise. Another what if thread; What if these 2 Convair Jets were twins instead of 4 holers? Same performance, same size, same capacity etc
You did not have any engines to be able to do that in those times. You could never get that performance out of the engine technology available at that time. So you question is really not realistic.
B777LRF From Luxembourg, joined Nov 2008, 1829 posts, RR: 4
Reply 9, posted (4 years 4 months 2 weeks 5 days 11 hours ago) and read 2660 times:
The APU on a 777F has more power (though none of it is used for thrust) than the first generation turbojets. When the CV came out, it was using generation 1.5 of turbojets, still offering less thrust than even the first generation CFM56-3 engines.
But, I suppose that in another 50 years someone born 30 years from now will ask "Why did they use turbofan engines back then, and not a Hyperdrive?"
From receips and radials over straight pipes to big fans - been there, done that, got the hearing defects to prove
milesrich From United States of America, joined Jul 2003, 2078 posts, RR: 6
Reply 11, posted (4 years 4 months 2 weeks 5 days ago) and read 2300 times:
Quoting BMI727 (Reply 5): That simply was not possible at the time. Engines just did not have the power to achieve that.
The development of airframes depended on the development of engines. This was true in the piston era and in the jet age. If you read this board, you would know that the jet engines that powered the first airliners, the DC-8 and 707, as well as the CV-880, came from military applications. The J-57, 75, and 79 were military designations for the P&W JT-3, JT-4 and the GE CJ-805. The first JT-3's only developed 10,000 of thrust. The JT-8D, which powered the DC-9 and 727, produced was the military J-52. The development of this engine enabled Boeing and Douglas to build twin and tri-jets that could carry economical payloads. Hi Bypass engines came along with the development of the C-5A and 747, and of course, rest is history, but the basic premise of this thread is nonsensical. Not only that, there was a preference for four engine airplanes by the public and the airlines. Look how many airlines replaced Convairs with DC-6's to carry another 10-20 passengers when payloads averaged less than 50%. The business has changed. The economics have changed, . . . . . Perhaps if Convair had designed their aircraft to accept P&W or RR engines as alternatives, or designed a fuselage that could have been stretched, they could have sold the airlines on the comfort quality of 2-3 versus 3-3 seating, but American nixed that idea in 1955 when they told Boeing, widen your airplane or we are going with Douglas. The whole idea of three American manufacturers developing aircraft that were so close in application just made no sense. Convair originally thought that targeting the medium range market would give them a niche, but then Boeing, at United's request produced a lighter weight, less expensive, medium range 707, the 720, and instead of ordering Convair, ordered the 720. Remember that the non fan jet 720 sold the exact same number of airframes as the 880. The fact is that once the 727 was put into production, the market for the 720/880 was very limited, and at the time these aircraft were first sold, there was no fan jet other than the after fan RR Conway, and the GE CJ805 that powered the 990, and neither of those were a match for the JT-3D. Convair was successful building smaller twin propeller airplanes, plus they were also fortunate to have the Glenn Martin Company as their competitor, a firm that knew nothing of about building transports and proved it. The same might be said about Consolidated Vultee but they got their act together and improved the originally 240, and they also benefited from large DOD contracts. The beginning of jet age was an exciting time to live through, but at the beginning everything was speed, and a sort of bubble attitude on the part of the airlines that if their competitor had a new plane, they needed one too. And this really was the environment until deregulation. Hence, Eastern, Delta, Continental, National ordered 747's. There was a time 35 years ago that you could not compete in the Mainland - Hawaiian market or the Trans Atlantic market without wide bodied airplanes. If United or American were able to buy 757's in 1975 and fly them on the Hawaii routes against competitors 747's, and DC-10's, they would gone broke. Western tried it and was not very successful. TWA operated that round the world service for a short period of time with the 707, and if they had had good loads at least on the LAX-HNL leg, perhaps they would have hung on longer with it, but as I said, no one wanted to fly in a 707 when they could take a 747 or DC-10.
aviatorcraig From United Kingdom, joined Mar 2010, 437 posts, RR: 0
Reply 12, posted (4 years 4 months 2 weeks 4 days 23 hours ago) and read 2254 times:
Also bear in mind that ETOPS did not exist back then. ALL aircraft that were going to spend several hours over water were 4-holers. It was only many years later that the three-engined L-1011 and DC-10 broke that mould before they too were surpassed by the newly approved ETOPS ops of the 767, A300 etc.
To have fitted the 880/990 with just two engines back then (even if such powerplants existed) would have restricted its possible missions against the competitors 707/DC-8/VC-10/IL-62
milesrich From United States of America, joined Jul 2003, 2078 posts, RR: 6
Reply 13, posted (4 years 4 months 2 weeks 4 days 22 hours ago) and read 2202 times:
Quoting ebj1248650 (Reply 10): Found that very interesting. The twin with the aft mounted engines was an especially interesting idea. I presume Convair determined there was too much competition to pursue the project?
Once Convair (General Dynamics) took the hit on the 880/990 project, taking a writeoff of an unheard of at the time $475 Million, they got out of the large airframe/airliner business. Those drawings must have been done before the decision was made to "shut it down". I don't remember if taking the loss required them to scrap the tooling or not.