Originally Posted by
gulliBell
I wonder why they just don't manually pop the floats and let it float to the surface by itself...probably a good technical reason why...I don't know.
It's possible the bags went off as soon as the immersion switches were exposed to water if the system was armed. This is unlikely, but could explain spreading of the wreckage.
Assuming the bags are uninflated, the system is electrically actuated, and since it sounds like the circuit breaker panels in the cockpit are separated from the rest of the wreckage, the system would not function even if it was triggered.
The primary reason this wouldn't be entertained as a viable solution is because the floats are not designed to raise a broken airframe from under water, but are rather intended to keep an intact airframe (and it's occupants) safely on the surface. Raising anything from the bottom of the sea is a delicate and calculated exercise. Float bags are placed at key points to maintain the structure's orientation as it is raised, and are slowly inflated to control the rate of ascent. This prevents the structure from shifting and further disintegrating, which would risk losing important information that would aid the investigation, as well as making a big mess to clean up.
If we go full mythbusters on this idea, lets assume a perfectly good S92 is sitting in 40m of water with a fully functional emergency flotation system. The float bottles are serviced with a nitrogen and helium mix to around 2500PSIG. I don't know the exact number offhand, but I think the floats are around 5PSIG when fully inflated. So while the pressure at 40m is around 60psi, the bags might still inflate enough to raise the aircraft to the surface. Again, though, I think the weight of the QCA (rotorhead and MGB) would cause it to flip upside-down along the way.