Bob stone said;
After watching so many posts about the use of various kinds of aluminum,
I want to put my 2 cents in. I am not an aeronautical engineer or anywhere
close to it however it seems to me that no part that is subject to stress of
any kind, shear, tinsel, etc should be made out of anything other that the
best quality steel. In this category are wing attach fittings, flight
control hinges and all other parts in the flight control system, engine
mount and certain parts of the landing gear. Of course this would add
unwanted weight but it would make a lot safer finished aircraft.
(Special note to flamers, do your damdest, I have a thick skin)
OK; should we make them thicker too? We might end up to heavy to fly, but
SAFE.
BTW, tensile strength is a good measure of one-time strength, but most all
aluminum has the same FATIGUE strength of "Pots and Pans" aluminum.
Oscar, pull out the Timeshenko for 'em.
Yet another issue.. many aluminum alloys harden with age. If you see a good
buy on rivets, they are probably hard as hell. Some alloys can be annealed
and kept in your wife's freezer for while. Take 'em out, form 'em, and let
lay around the shop for a while to harden.
Japanese ZERO's were made with a 70 series alloy for spars(7078 ?) ; a
limited life wartime issue. The Spars crystallized and fell apart; that's
why there are Zero Zero's around, except replicas.
Aluminum is a marvelous material, used properly. Here in Lee county we have
a mosquito control of seven (spray plane) DC3's built in the 40's. They are
not made of steel.
Ron Freiberger
mailto: [email protected]
