What is wrong with this picture?

[Ninelives]

My father was in the army in WW2 (Signals) and witnessed German planes burning very quickly but wasn't sure why. Then one day (after D-Day landings) he found some German a/c wreckage to use for materials and set about heating it up to bend it only to find that it went up in a white hot flame in his hands! Luckily he wasn't injured but he then understood why some parts of some planes burned very quickly. He has confirmed to me it was magnesium and was probably used simply because there was more of it available. (or weight saving as said above)