A Technological Appendix to Postblogging Technology, September 1953, II: Missing Plugs, Missing Rebuttals

 

Is that a bandwagon going by? Let me hop right on that thing! 

I am going to go with the assumption that no-one wants to hear my potted history of Boeing's ongoing struggle to not embarrass itself with the millions of 737s-only-slightly-different it is currently selling to the airlines that only want 737s. (Even if they are slightly different.) I'm not saying that there's anything wrong with an  industry being locked into an airplane that looks and acts like an old-time 737 in spite of having a ridiculously large pair of engines dragging off their wing and a whole app on its computer set up so that it will fly like a 737 even though if you use the app wrong you crash and die. 

Because if I was going to make fun of this situation I'd say something like "Good thing grandparents don't fly planes," and then the dam would burst and I would point and laugh and laugh and laugh, and we're way more serious about that around here. And anyway it frankly doesn't even crack the top fifty of inexplicable institutional malfunctions we've got going on these days. (Just kidding about "inexplicable." It's obviously all the old people we've got these days.) 

On the other hand, I can go back to 1953 and the approximate moment we got locked into this path and try to understand how we started down it.

 When I first encountered the Avro Atlantic, not that long ago, it was for a bit of eyerolling. On the one hand, you could see why the various V-bomber builders would float airliner variants. On the other, pull the other one, it's got bells on! The VC7 was a quite sufficiently radical departure from existing airliner practice. If anything, it would be a Victor descendant that would fill the role, not that any such thing ever happened. 

On the other hand, what's an established airliner practice? The Comet doesn't look anything like a Boeing 707, and it wasn't a problem with the design that caused problems with the Comet, but rather the corporate irresponsibility that led De Havilland to float a lightweight airliner structure in the first place. There was nothing wrong with the Comet 3, apart from its poor economics. 

We know the story: Boeing put the engines in pods, de Havilland put the engines in the wings, and while pods are winners in the long term due to their ability to accommodate very fat turbofans, with their fuel economy and silencing, they were also winners in the short term. That is, there were reasons for buying the 707 or DC-8 instead of the Comet 3 or the VC10 based on the podded engine design, even before the appearance of high bypass turbofans. These arguments were put forward by Boeing's George. S. Schairer at some or another SAE session and subsequent venue, including the Fourth Anglo-American Aeronautical Conference, held in London in September of 1953. What we don't know is the contents of the refutation to be given by Avro's S. D. Davies, who was understood to be coming to the podium "loaded for bear" until the talk was cancelled out of security concerns. William Farren suggested that this was because the Vulcan was still secret, but I am pretty sure that this was a facetious comment, and several British attendees referred to the argument that podded engines were less likely to damage the aircraft with flying turbine blade fragments in the event of a turbine explosion. Davies pointed out that "We don't have turbine failures," while A. A. Lombard of Rolls Royce pointed out that American engines used austenitic steels, which got "spongy" at high temperatures, whereas British engines used chrome steels, and did not have this problem. F. R. Banks made the most reasonable point, which is that you shouldn't be taking turbine failures for granted any more than you should be taking cabin pressurisation failures for granted. (Not that that would age well, with the first mid-air Comet loss only four months away.) A very young Bill Gunston provided advance notice of the Davies' criticism in Flight a few weeks prior, placing heavy emphasis on engine failures in the B-47, and at some point, someone pointed out that, with the B-47 the only useful Western atom bomber in service, this was not the time to be talking it down.* Thanks to the wonders of the Information Age we need only search the Aviation Safety Network for the B-47 and find that, through the Fourth Conference, 25 B-47 total hull losses had occurred,  3 definitely due to engine failures and another 3 due to unexplained explosions in mid-air. A more extended discussion would look at the J47's safety record in other installations, but the losses through September of 1953 do not paint a particularly pretty picture of a plane that was already known to be predictably difficult to fly and land due to the high wing loading and flex, leading to aileron reversal. 

At this point it is perhaps more explicable that, per Wikipedia, "Avro is reported to have considered a civilian version of the Vulcan as 'inevitable' in 1954--55." Advantages including lower ground weight, lower landing speed, and higher cruising speed would seem to justify this confidence. And although at the time it would have had no chance to be the first turbofan-powered airliner, since the VC7 had not yet been cancelled, the Atlantic was proposed with Conway engines. Altogether, the airlines' decision to pass over the Atlantic in favour of the 707 and DC-8 needs more explanation than it gets. Delta wings can, and have accommodated podded external engines. The Atlantic obviously could never have been retrofitted with such engines, but at the time British manufacturers were thinking of relatively short production runs of aircraft (and much less capital investment in tooling) taking advantage of steady improvements in aerodynamics and engine technology; the question would have been taken up in the Atlantic's successor.

It was obviously not to be for all sorts of good reasons, so it is just as well that Everything is Fine in modern commercial aviation. Maybe one day we'll even know what the good reasons were!  

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For them as likes a citation, that's David A. Anderton, "Security Scuttles Pod Debate, Aviation Week 59, 13 (28 September 1953): 19; and W. T. Gunston, "Pod Pros and Cons: Some Reflections on American and British Engine-installation Methods," Flight No. 2329, Vol. 64 (11 September 1953): 371--4