Pilot photo and envelope hidden in Luftwaffe book

I recently purchased a copy of Fliegende Front (Flying Front) 1942 first edition. While turning the pages this German 'Foto' envelope was revealed, and contained a picture of an American pilot.
The envelope is obviously German and contains the name Hans Schafer. Who was a Luftwaffe ace.

I'm wondering on the 'Foto' envelope has any one seen a similar item before. Does anybody have any in site on what the other information at the top of the envelope is... Heideweg104? I do believe it is from the war period.

On the actual photograph does anyone know what kind of plane is pictured. Could this pilot be a German that was trained post-war in the USAF. I cannot understand how the two got put together.

Please see attached pictures. And feel free to give any ideas, thoughts, and advice.

Kindest Regards

 

I;m guessing a bit here, but the shape of the cockpit framing looks rather like a B-25 Mitchell.....?