MTS V22.1.0-BETA9 broke UNU Helis. This was allegedly a fix to fix planes from gliding up with the engines off, however in my testing, they work fine in BETA 8 (I tested the UNU Navigator as well as all OCP planes).

This is a ticket in reference to our discussion in PMs

Fixed in V22.2.0. Well, back to the way it was in the beta before this one anyways, just a little less thrust than before.