A friend sent a picture of the snorkel setup-it mounts thru the left cabin opening. Looked substantial. The video provoked some thoughts about qualifying a new design. One obvious first subject to address is that given the fact that one would want to be able to refill the tank in windy conditions, doing incrementally increased paced forward flight with a pace truck/monitor would establish an envelope within which the snorkel could be flown. Now that would be level flight and would assume one extended the snorkel after coming to a hover. If it was needed to deploy the snorkel in descending flight conditions, the aerodynamic issues get more complicated and harder to predict. I recall when we added external aux tanks to the 53 there was a near real problem while doing the tank jettison tests when the next increment of speed/rate of descent resulted in the tanks going up instead of down.
In the case of this S-70 accident, it would be useful to know what the flight envelope test plan for the snorkel entailed and what operating envelope existed.
Sas-have to run to our unofficial/unlicensed retiree lunch where one finds out how things really got done at SA! I’ll try and find the Ft Campbell pic when I return.