My guess it that it's not the tip gear (that's mainly there to keep the wingtips from hitting the ground, because the 52's wings flex so much), it's the configuration of the main gear. The B-52 doesn't have a nose gear and two main gear, it has essentially four main gear, all quite close to the centerline. So even though its main gear consists of double wheels instead of the production 36's four-wheel bogies (meaning it actually has two fewer wheels, if you don't count the tip gear), I would expect it does have better (longitudinal, if not lateral) weight distribution.

Also, comparing maximum weights doesn't really tell as much as it implies, since aircraft rarely operate at their maximum weights; it's possible that the later B-52s operating out of that field were restricted to operating at less than their absolute maximums specifically so as not to break the field, or that the runway had been improved by the time they came along. (I know I'd put the latter on my to-do list if I had a bomber fall through my base's runway. :) It's also worth considering that aircraft making emergency landings are generally a lot heavier than they normally would be when trying to land - and that landing, for obvious reasons, usually places greater stresses on the runway than takeoff. After all, if you're careful, you can walk across a surface that would collapse if you fell on it.

Of course, all of that is just educated conjecture, as I am neither a civil nor an aeronautical engineer.

--G.
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Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
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