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Joe Perkel · 17 June 2009, 06:48 PM

Hank,

Taking a moment to analyze the VN diagram, certain things are clear however, would you please take a moment to clarify a couple of items?

Clearly understood

4 g's @ 150 mph produces structural damage, 6 g's structural failure. Conversely, -2 g's @ 150 mph = structural damage, and -3 g's = failure.

Questions then

-What is the +-50 feet per second gust line, and how does that figure into this?

-How do you calculate and plot these failure modes? There is a lot of hidden work in this diagram, IE when does one simply deform any single component vs break another at X speed and G's?

17 June 2009, 06:48 PM	#248 (permalink)
Joe Perkel Forum Ace Join Date: Oct 2007 Location: Miami / Sebring, Florida Posts: 1,280	VN Diagram Hank, Taking a moment to analyze the VN diagram, certain things are clear however, would you please take a moment to clarify a couple of items? Clearly understood 4 g's @ 150 mph produces structural damage, 6 g's structural failure. Conversely, -2 g's @ 150 mph = structural damage, and -3 g's = failure. Questions then -What is the +-50 feet per second gust line, and how does that figure into this? -How do you calculate and plot these failure modes? There is a lot of hidden work in this diagram, IE when does one simply deform any single component vs break another at X speed and G's? __________________ Joe http://sopwith-baby.com/ M.V.R. Showed us what happens when you don't stick to your own rules. Last edited by Joe Perkel; 17 June 2009 at 06:56 PM.