Originally Posted by
Chris Scott
But, generally speaking, would it be fair to say that those accidents were less about sophisticated systems and more about the relatively new flight envelope that those airliners were operating in, the engines and the aerodynamics? The 707/720 and DC8 cruised at higher Mach than the earlier, ill-fated Comet 1, which had failed to sell in the US. The 727 was a hot ship with a T-tail. Flight crews were unaccustomed to the environment, and - unless ex-military - had no experience of the different flight characteristics associated with jet engines.
Current types fly no faster or higher than those did (sad to say). Think of the CV990...
Interesting take, Chris.
While you're absolutely correct in terms of specifics, my reading leads me to the conclusion that every "generation" has had its own share of problems on introduction as a result of the innovations applied to them. Going back to the infancy of civil jets, I remember reading a book some time ago that quoted a retired DH engineer as saying he was informally told by a counterpart at Boeing that if the Comet 1 had not served to identify the problems with pressurisation/metal fatigue and over-rotation with a swept-wing design, the Dash-80 would have suffered the same issues - and possibly the same fate - as the Comet 1.
A generation on, the "deep-stall" issues with T-tails were another generational issue that were first experienced on this side of the pond, but the B727 suffered a spate of crashes shortly after introduction because pilots were letting speed bleed off too quickly on approach and the tail-heavy design impeded recovery. This may have been an issue with the DC-9 as well, but I'd have to do some more research.
With the advent of widebodies came two new issues - all-hydraulic controls with no manual reversion and the simultaneous introduction of advanced INS-based autoflight. The DC-10 was the most infamous victim of the former (and arguably should have been grounded while the problematic cargo-door latching system was fixed), but the 747 was not immune if maintenance was not done properly.
Autoflight issues carried on through to the following generation, and while the introduction of FBW with that generation wasn't without problems, it was less problematic than feared at the time.
The latest generation is a case which is likely to be unusual, as the two predominant manufacturers have followed separate business cases to inform the designs. The ultimate goal is similar - i.e. reducing weight and cost, but one manufacturer has gone the way of placing unprecedented loads on their airframe and the other has utilised composite materials to an unprecedented degree. For this reason there may be underlying issues specific to one type alone from which the competition can draw little use.