Seeking Photos of Over-Stress damage / popped rivets

[Randy Haskin]

Do any WIXers have photos showing over-stress damage to aircraft? More specifically, I need a shot showing either popped or pulled-through rivets.

Given how many of you have access to wrecks being restored, I was hoping somebody would have an airframe with this kind of damage.

[JohnH]

When I hear the words pop and rivet...together as in pop rivets...I think of a certain Defender building Canadian who has been mentioned on here recently.

John

[bdk]

Do any WIXers have photos showing over-stress damage to aircraft? More specifically, I need a shot showing either popped or pulled-through rivets.

Don't have a photo handy, but rivets that are overstressed will either shear (the shank will be cut through by the sheets of skin), pull through after curling up the edges of the rivet heads, or pull the rivet head off. An incipient rivet pull through would show the edges of the rivet curled up so that there is a depression in them (on a flush head rivet). Sometimes the countersink in the skin looks virtually undamaged. Protruding head rivets normally don't pull through. Rivets usually pull through from skin buckling which imparts a normal force on the rivet head. Current design practice dictates that the skin should fail before the rivets pop though. After all, if the fastener fails there is more strength capability left in the remaining structure that is not utilized.

Crash damage is a good place to find what you are looking for since the forces imparted follow load paths that were never intended by the designer.

[HELLDIVERS]

HI LOOK FOR PUCKERS OR DISTORTION OF THE SKINS OR MISSING RIVET HEADS,OR SKIN BUCKELING FORE OR AFT OF WING ATTACH AREA,AROUND LANDING GEAR AREAS, TAIL ATTACH AREAS,ECT.CHECK SPARS FOR THE SAME.LOOK FOR SMOKING RIVETS THESE ARE RIVETS THAT WILL LEAVE A BLACK POWDERY STREAK AROUND THE HEAD THIS IS THE SIGN THAT IT IS LOOSE AND IS MOVING, THE BLACK TRAIL IS ALUMINIUM OXIDE.IF YOU KNOW THE A/C HAS BEEN OVER STRESSED OR A HARD LANDING A AIR FRAME INSPECTION IS A MUST.THANKS MIKE

[Randy Haskin]

I'm interested in seeing both situations where the rivet head has popped off (e.g. just a countersunk hole in the skin) *and* where the rivet head has deformed and pulled through the skin.

I am putting together an instructional presentation for my students (Uup-and-coming USAF fighter pilots) on how to spot damage on your flight lead's aircraft during a post-fight battle damage check.

Every time we go dogfight, when the fighting portion is over we perform a visual in-flight inspection of the other aircraft. I want to be able to illustrate what rivet damage due to an over-G would look like.

Thanks for the resposes so far.

[Locobuster]

Randy. I went through everything I have and here is a P-51 that was ground looped by Lt. William Halloran, 79th. Fighter Squadron, on 12 June 1945. There's some stressed areas visible but no popped rivets that I can discern...

[bdk]

I'm interested in seeing both situations where the rivet head has popped off (e.g. just a countersunk hole in the skin) *and* where the rivet head has deformed and pulled through the skin.

I've got a copy of a Southeast Asia Battle Damage Report. Let me see if I can find it and if it has any of the photos you need.