A colleague, identified as Dieter, told Europe1 that Sonderheimer was a trusted pilot, saying:
He was someone very reliable, he was one of the best pilots we had. I am 100 percent sure they did the best they could. Thats what I think because I knew him very well, he was one of the best, he had a lot of experience, he had more than 6,000 flight hours behind him.
“He was a quiet man.”