Re: Gluing aluminum



Ed Huntress wrote:

"David Billington" <djb@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:46FFCC28.50807@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


Ed Huntress wrote:

"David Billington" <djb@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:46FFAC22.4010402@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Ed Huntress wrote:

"Jman" <mooglieman@xxxxxxxxxxx> wrote in message news:1191158765.159816.160540@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

I think I'd rather take the train or bus thanks.......


http://seattletimes.nwsource.com/html/businesstechnology/2003612251_boeing111.html

http://findarticles.com/p/articles/mi_qa3618/is_199709/ai_n8765992/pg_4

I wrote articles almost identical to those 25 years ago. IIRC, the L-1011 had a carbon-fiber tailfin, as well. And the other story is the same old, same old for the high-performance composites business. Very little appears to have changed.

A lot of people don't realize how much epoxy is used throughout the structure of an airliner. They probably don't want to know. d8-)

However, they also don't know how much fatigue becomes a problem in all-aluminum aircraft that were designed over the last few decades. DC3's are still flying because the engineers didn't know what a reasonable safety margin was. Now they know, and the life of those planes is finite.

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Ed Huntress

I was told by late father, who was in the aerospace industry in the UK and later US as a stress analyst, maybe 25 years ago that one of the reasons the DC3 kept flying because you could still get fuselages and wings. When the life of the wings was up you bought new ones and the same with the fuselage. I expect like many planes the airframe life is also re-evaluated after actual service conditions have been experienced and extended or otherwise revised.

I think that's true, but I flew in DC3's in Canada's Northwest Territories that still had fabric-covered control surfaces. Those were *old* DC3's, and it was only 20 years ago that I flew in them.

If fabric covered what was the structure of the control surfaces made of?. I don't know much about wood structures so don't know if they suffer from fatigue.


I don't know for sure, but most likely they were steel tubing. That was the most common way to build a whole airplane in the 1930s, before the aluminum-skinned construction became common, and it was used for small planes as well, including the Piper Cub, the Aeronca Champion, and so on, into the '50s and some into the '60s. Today, homebuilts are often made that way in the US. My understanding is that amateur-welded steel tube frames are not allowed for homebuilts in Europe, correct?

No idea on the homebuilts in Europe except you reminded me a microlight flyer my neighbour knows who I met next door with the top of his control stick asking about repair, it had snapped off when he was coming into land, the lightweight tubing of the control stick had failed at a drilling through it where a control cable ran, no reinforcing of the area. Luckily he was just about to land a no serious damage occurred but it could have been far worse. The microlight looked more like a proper plane as with the regs here and the advanced materials it was fully enclosed.

Regarding your comment about steel tube planes, before you replied it occurred to me earlier that 2 of the reputed greatest British fighter planes of WWII were the Spitfire and Hurricane, the Spitfire being all metal stressed skin construction IIRC and the Hurricane being a steel frame and fabric covered IIRC, 2 differing constructions and makers, same engines IIRC but in the circumstance not much too choose between them, although I have read the Hurricane construction made it less susceptible to damage from bullets and shrapnel.




They just stood up a lot longer. They also had severely reduced load capacities because of the overbuilding.

In the science museum in London there is a section of a 747 fuselage. It's quite surprising how thin the outer shell is, looks to be about 2.5mm from memory. Not that I have a problem with that as with a background in engineering I know some damn good people design these things and the 747 is a strong aircraft judging from the bits that has fallen off them and they still kept flying.


Sometime take a look at the *** metal from which the engines hang in a DeHaviland Comet. It will make you gulp.

If I have the chance to see one up close i'll have a look. I went to the Shoreham UK airshore a few weeks ago and had a Lancaster bomber creep up on myself and a mate, it came over the hill behind us and was upwind so we didn't hear it coming until it it was quite close, it passed overhead at maybe 100', amazing noise. Had a group of about 6 spitfires pass over as well many times. Quite a fantastic noise. Looking at the engine cradles they look quite weak but must do the job. It was pointed out to me relatively recently that aero engines differ from car engines in that the engine must have bearings to take all the thrust generated by the prop to drive the plane along.



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Ed Huntress



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