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Angier Ames wondered why no one responded to his post on MKII tail flutter and

the flap preload.  



I guess everybody is still exhausted from the discussion 3 months ago on the

tail question.  I telephoned Martin at that time to understand his view of the

situation and came away unconvinced that there is a problem.  Apparently his

ground vibration experiment validated his FEA model but there's been no attempt

to validate the aerodynamic excitation conditions (forcing functions for those

of you with dim memory of introductory dynamics).  Martin explained that this

part of the model is used by Boeing and taken on faith.



My skepticism arose because he predicted flutter at very low speeds and if he

was correct I would have expected a rash of related accidents.  To my knowledge

there have been none so the most likely explanation is that the analysis is

incorrect - probably related to how aerodynamics are handled in our category of

aircraft.



I have not heard anything about flap preload either.  BTW Angier, if your plane

goes together anything like mine, I bet those rear windows are really gettting

in the way right about now.  The worst part of the whole construction process so

far has been lying across the seat back and rear bulkhead reaching into the tail

section for antenna placement (Com2, ELT, HSI flux module).  Damn am I glad the

hydraulic pump is behind the seat!



Best Regards,

Ed de Chazal