I'm not really sure I followed the film itself, but it's nicely shot and there are some typical (?) 1960s philosophical debates between the various characters about life. Probably "feminist" in that several of the woman are clearly only interested in relationships with men on their own terms, but that doesn't stop them throwing in a bit of tasteful female nudity along the way.
The thing that really impressed me however, was the clip of the vertical take-off and landing of the experimental Dornier Do-31 E3 - the world's first (and still only) VTOL cargo plane. The E3 was one of only three built and this is a really nice sequence showing the impressive takeoff, a bit of flying and the somewhat-heavy landing. The project was cancelled in 1970 but the E3 is still on display in a museum near Munich.
Worth a look.