 The HP-22 was to be a 2-seat amphibious sailplane, again self-launching, but was abandoned after the wings and most of the fuselage hull were completed.In the period following the HP-18's heyday, Schreder also spent a great deal of time attempting to develop a lightweight jet engine for small aircraft.Schreder envisioned such a powerplant as being ideal for self-launching sailplanes.