yep, if in the right condition things are pretty much in a time capsule underground!
I once took part as a consultant to the recovery of a Bf109 in Italy, the plane had crashed in 1944 and was quite deep underground, so much that the first bits were found 3 metres under the ground level.
The hole was quite boggy as there had been some strong rains the week before, and there was some water at the bottom. Three people were digging gently as they were going down, and I warned them about the potential risks of finding unexploded ammunition, which in the case of the 109 meant big 20mm and 30mm shells filled with explosives. As they kept on digging the smell of fuel became stronger, then all of a sudden there was a crack, a big hissing sound and a lot of smoke coming out, needless to say they all jumped out of the holes like cats and we all ran for shelter! What happened is that one of the bigger bullets had separated from the spent casing and the phosphorous of the tracer behind it ignited!
They learnt their lesson and let the bomb squad we called take care of the rest, which came out without too many problems.
A lot of the parts had evidence of the impact force: the front of the ammo box areas were all peppered with holes because the impact was so strong the ammo darted forwards and poked holes on the front of the box!
Some of the rests of the pilot were found molten on the back of the engine crankcase, and many rivets popped out of the wings as well. The propeller blades were surprisingly straight(ish), sign that the engine was probably stopped and the props feathered when it impacted the ground.
The surprising stuff though was that stuff like the tailwheel was perfect, and the guys managed to inflate it back!
Some time ago I stumbled across this incredible find in Russia, where the pilot's body was still intact and preserved in incredible conditions!
WARNING, THE IMAGES ARE QUITE GRAPHIC AND MIGHT OFFEND YOU, SO DON'T LOOK IF YOU THINK YOU CAN'T HANDLE IT.
http://www.documentingreality.com/fo...decades-73403/