Let's fix this
Terrain awareness/avoidance/ alert warning system or TAWS. Not TWAS. Although everyone will know what you mean. With all the confusion over TCAD versus TCAS and their many derivitives, which actually are different, as defined by most, it can help to use standardized acronyms. Call me picky or worse, no issue there.
Most on this forum probably agree that TAWS would not have saved these people unless the pilot were moving much much slower, in which case if ( the assumed) loss of control due to vertigo was the cause, it might have been avoided anyway. Even with that, we all know the irritation of flying low level all day and having to mute the system if possible. Same with TCAS when approaching airports, when they are busy. Acceptance and favor of these systems is also personal. Some like them, some don't. I do think that all HEMS operators should have TAWS. I also think that any 135 IFR helicopter operation should also have both systems; if for no other reason than the safety of the clueless passengers in the rarest of rare occasions that it works with a positive outcome. The latter leads me to my point. I wonder how many instances of TAWS alerts have actually snapped someone to attention so they could make successful corrective action and live to fly again? Any there I was stories are appreciated. Deus ex machina.