I was at Ramstein during Flugtag '88 and the C-5 crash two years later.
Cause of the Ramstein C-5 crash was thrust reversal activation (or so that's what was printed in Stars and Stripes (European edition of Pravda). Heard engine run up for takeoff followed by a very loud boom and the subsequent crash around 1:30 a.m (sounded like a few dozen garbage bins being thrown down the street). Don't even want to go into details about Flugtag
Otherwise the C-5 has a pretty good safety record.
Yours, Mike