Not having read all the post, and I'm not looking to stir up a cans of worms. But aircraft aluminum is a special alloy that is already hardened and stressed. Aircraft also must under go annual inspec
Depending on the aircraft, the typical alloys you find are the garden variety 6061-T6, 2024-T3, etc. Certainly nothing more exotic than 7075-T6. 6061-T6 is the most common structural aluminum manufac
They do, if allowed to flex often enough! I lost more than one element tip (on a commercial antenna) before I learned the "rope trick" years ago. ____________________________________________________
To be very technical airplanes are work hardening and stress cracking and breaking down that is why there is a maximum hour limit on the airframe. The antenna is work hardening too, but the cost of i
I had a ride on a B-17G built in 1944 just a few years ago. It had flown over thirty combat missions with the Eighth Air Force according to its Form One, the aircraft's log, and has been flying aroun
Author: w7ni@easystreet.com (Stan or Patricia Griffiths)
Date: Mon, 11 Feb 2002 22:39:00 -0800
In my opinion, if you inspect your aluminum tower and find cracks in it and have to take it down, it HAS failed. The consequences aren't quite as bad as if it FALLS down . . . but if it fell down, a
They do - that's why manufacturers used to recommend rope in the elements to dampen the vibes. Force 12 has eliminated the low windspeed vibrations by using an aggessive element taper so they don't n
I owned a 1964 Cessna 150D for almost 10 years. I was the forth owner. This aircraft had over 9300 hours on it when I sold it. Cessna publishes no maximum hour limit for this airframe. Very few parts
I don't think anyone is arguing with that. Any item that fails in normal service is either not properly designed, or not properly built. However, aluminum IS much more subject to work hardening than
I just want to expand on this a little - comparing the aging properties of flexing steel vs aluminum. BTW, I'm not a materials (or any other kind of) engineer - my thoughts on this subject are formed
Comments inserted below: 25 years in the tower business? ...and you're just using suppositions? Where's the evidence? You use the phrases: 'load them to the hilt' .. and 'know that' ... Suppositions
Don, Thanks for your comments. I didn't represent anything I said as evidence. As a thought experiment, it's legal to "know" something like that. Are you suggesting that the failure mode is exactly t
To continue the aircraft parallel, aircraft are designed to withstand many positive and negative Gs, as well as wind loads, so their members end up being tremendously stiff compared to antenna elemen
<...Five months ago I took down a 40 foot heights tower. It had been up since the 60s. Larry went SK qrt. We lowered the kt34 and the 2 meter beams, then we just tilted it over !!! The Big Aluminum A
I put my Universal up with stainless bolts. Its time in service is not enough to extrapolate yet. 73, Ken AB5A <...Five months ago I took down a 40 foot heights tower. It had been up since the 60s. L