In Samizdata, Brian Micklethwait goes back to his Airfix modelling days to rediscover his admiration for Avro’s Lancaster bomber. In the process, he discovers just how strange the evolution of that aircraft actually was:
In the late 1930s, believing that bombers would always get through and that they therefore had to have lots of bombers or lose the war, British Air Officialdom had two ideas about how to build a bomber. They accordingly announced two specifications, which different potential bomber-makers were invited to meet with their designs. They wanted a two engined bomber, like those that the Germans bombed Britain with in 1940 but better, or like the Wellington but better. And they wanted a much bigger four engined bomber, such as the Germans never got around to building, and like … well, like the Avro Lancaster.
So, the Lancaster was Avro’s answer to the second requirement? Actually, no. Or, not at first. Britain ended up with three four-engine heavy bombers, the Short Stirling, the Handley Page Halifax, and the Lancaster. But strangely, by far the worst of these three, the Short Stirling, was the only one of the three that was all along intended to be a four-engine bomber. Both the Halifax and the Lancaster started out as answers to the two-engine specification rather than the four-engine one.
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In particular, all the work that Avro had done improving, as they had hoped, the fuselage of the Manchester, which had done nothing to improve the Manchester, suddenly came into its own in the new configuration. Ever since I built my Airfix Lancaster as a child, I have wondered about the oddity of that Lancaster fuselage. Simply, this fuselage seemed too small for the airplane as whole. And the wings seemed too big. Not ugly exactly, in fact not ugly at all, but nevertheless a bit like the arms of one of those misshapen body builders with excessive biceps. My Lancaster photo (above) even shows how the wings between the fuselage and the inner two engines go straight out rather than tapering, as if these wings were only widened late on in the design process. Now, all that makes sense. The Lancaster’s fuselage began life as the fuselage of a smaller airplane. No wonder it looked to me too small. It was too small. The Lancaster’s wings look stretched because they were stretched. It is only now, after half a century and more of gazing at the Lancaster, that one looks at the Manchester, and sees its fuselage as too big and its wings as too small.
The birth of the Lancaster illustrates a general point about making airplanes, which explains why successful airplanes often fly on for so long. Consider the airborne WW2 mega-hit, the DC-3 (aka the Dakota), and then later the big Boeings, the B-52 and the 747. The Lancaster didn’t last as long as those hardy perennials, because propeller driven heavy bombers were soon replaced by jet bombers (like the B-52) and by intercontinental ballistic missiles. But even the Lancaster flew on for many decades, in the only slightly altered form of its close cousin, the Avro Shackleton, which only went out of service in 1991!
