RV-7 rudder flutter - heavy tail strobe

[A2022]

do you really need such a heavy tail strobe mounted at the very most trailing edge of the rudder fairing, what about a using lighter strobe?

just because Van's supplies a mounting location at the rudder trailing edge does not mean it's OK to add a dead weight there. the trailing edge of the rudder is the worst place to mount anything. if you are going to mount anything there, make sure it is light weight. the stobes in the photos with the destroyed rudders appear to be wheelen and weigh about 1/3 of the pound!

it appears the flutter vibration sets a dumb-bell vibration between the rudder upper portion (with counterweight) and the rudder lower portion (with fairing and strobe) and rips the rudder in half. also, the upper and lower sections of the rudder probably have different resonant frequencies once they are separated, not that it really matters at that point.









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https://www.aviation.govt.nz/assets/pub ... ealand.pdf

[A2022]

z-tron tail strobe, maybe 10 grams (edit: it weighs 18 grams), very light weight. sheet metal mounting ring. I'll see if I can find my spare and weigh it.

the entire tail strobe installed assembly is probably 25 grams total. every gram is critical at this trailing edge location. folks may say, I'll never exceed Vne, but it can happen, why not have all the margin possible?

z-tron is out of business but he had a good idea for what is important to some, light weight. the installed light has been operating for 9 yrs and 1000 flight hours. it's been to 21K feet and the coldest -30C, and the hottest 41C.