Originally Posted by
HeliComparator
Who on earth thought it was a good idea not to power the AFDS system from the battery bus? It's not as if it could take any significant power! And who on earth put up with that poor design for 20 years without making a lot of noise?
EDITED to add this comment: ( People may. have put up with it for years and not made any noise because they were not aware that the immersion switches are not redundantly powered if the Gens go offline due to low NR and the APU is not on. A condition that would require manual float deployment by the crew upon water contact.) END EDIT
Well, i sure wish that someone would confirm and post a reference that the immersion switches are indeed not going work in the case that the Nr goes so low,( +- <80%, ) that the Generators fall off line and the APU is not on and working. If such is the case float deployment would require that one of the crew push the manual deployment switch on the collective. Also that would be a factor if the engines were off or at idle and not driving the rotor system at the time of impact. I can’t find any definitive warning in the out of date training manual, RFM and checklists I have to hand.
Having said that the much bigger question is “How and why the helicopter ended up in the water.”
EDIT : Looking at the video of the recovery it seems to show that the landing gear was fully extended but damaged during recovery. Tail rotor appears to rotate when the rotor head moves once lines were attached to the head during the recovery.