Thanks 212 and Jabby,I think on RAF SAR,this was a `known` fault with hooks but was mitigated by having a `pip-pin` attached ,on a wire,and then put into a hole in the `gate`,so it was locked.Maybe `Crab` or CJ can comment on later SAR times..
For the SAS troopers lift,I attached the abseil tapes,looped/double knotted to the winch hook,so we could winch if the trees were very high,as it was originally a pick-up from an LZ,but they(SAS) DIDN`T GET TO IT.
The later night pick-up of the stretcher/wounded had the tapes secured inside to the floor cargo tie-downs.Never to the cargo hook.