Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4417877 | Water-jet drive mechanism for driving and controlling of particularly shallow-draught watercrafts | Franz Krautkremer, Achim Kessler | 1983-11-29 |
| 4278431 | Hydro-jet propulsion device for driving and controlling of particularly flat-bottomed watercrafts | Franz Krautkremer | 1981-07-14 |