Hi, Franck
We have to take into account the constant change in frontlines when we discuss 100% losses.
http://www.ahs.no/ref_db/lw_loss_pub...?lossid=139322
An aircraft reported as missing, with the pilot returning later as in the case of Sauer is a very common occurence, and the explanation equally simple; for the Luftwaffe this aircraft would be considered as a 100% loss, since Fw. Sauer ended up in enemy territory, but was able to return to own frontlines. After the frontlines changed this aircraft could be recovered and repaired, the damage could probably be minor to a lot of the 100% losses listed in the initial reports filed shortly after Barbarossa, and we will find these aircraft 'lost' several times.
Look at the date, the aircraft was lost shortly after the launch of Barbarossa, in Soviet territory on the loss date, but as we all know the progress of the operation Barbarossa in it's initial stages made the Luftwaffe recovery team able to pick up loads of aircraft reported from the units a 100% losses.
Regards,
Andreas B