Luftwaffe 'R.L.M.' Stopwatch (Stoppuhr). The stopwatch is 'R.L.M.' (Reichsluftfahrtministerium) marked on the back. When dropping a bomb from a plane the deciding factors are the fall characteristics of the bomb, the flight altitute and the speed of the aircraft. These are best attained by measuring the time it takes to fly over a defined strech of land, measured between two points. Stopwatches are needed for this task. These stop watches were part of the bomb targeting device 'Görz' and other air force devices. The stop watch is maker marked by 'Joh. Hartmann' from Berlin. The stopwatch is having a Minerva Calibre 19 movement and is in functional and running condition, it is showing normal traces of usage, see photos. Wonderful authentic WW2 Timepiece!