Flight Düsseldorf Airport departs from Dusseldorf Düsseldorf Airport at 11:55 and arrives at Singapore Changi Airport at 06:20.
The flighttime is about 12h 25m. The distance travelled ("as the bird flies"): 10263 Km. So the average speed is roughly 827 Km.
There is an 6 hour time difference between Dusseldorf and Singapore