Boeing Wingbox Method BDM-6840

[johnjaundice]

Well this question is very specific, but maybe someone out there has some insight or has done this before.

Okay, so in BDM-6840, for a multi-cell wingbox, there is a process (specifically Step 10 of the method) where you reiterate the calculation of shear flow, q. It is multiplied by a carry over factor, COF somewhat like the moment distribution method. The problem here in Step 10 is that the numbers the manual's example is showing don't make any sense with the equation provided. My other stress engineer i work with is also perplexed and can't figure out if the manual's numbers are wrong or if we're just missing something completely. If there's some response on the thread, I'll go into more detail.

 

[WKTaylor]

johnjaundice ...

You have asked a question that requires intimate knowledge of a Boeing design manual and design/analysis practices.

I doubt if anyone here, with experience, will answer since tightly held company proprietary data is being discussed.

Suggest You call Boeing for clarification

NOTE:

IF this same question were asked regarding an extract from a commonly available text, [Niu, Bruhn, Falvel, USAF, NASA, etc] You might get some advice.

Regards, Wil Taylor

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