Very brief footage of the Doblhoff tip jet, Cheers Juergen
http://www.myvideonet.net/0_video_Autogyro_yt-GF9R9Zq6P9M_WW2%20German%20Doblhoff%20Jet%20Tip%20Helicopter.html
http://www.myvideonet.net/0_video_Autogyro_yt-GF9R9Zq6P9M_WW2%20German%20Doblhoff%20Jet%20Tip%20Helicopter.html