CH-53A Aerobatics
Helofan, the film that you saw is about all that I have ever seen while I was working.
There is another, really terrific film of Frank Tefft putting on an aerobatic and tactical demo ( including a lift of 125 Japanese infantry ) in a CH-53D, which includes cockpit coverage. I have that on tape somewhere, if I haven't sent it to my grandson.
Lt. Fubar, I never heard the behind the scenes story of why the 53A wasn't employed in the assault role. My personal guess is that they didn't want to risk that many Marines to a single shoot-down. As I recall the history of the CH-46 problems, it was one of those issues where the actual combat usage of the machine resulted in structural loads in the rear of the fuselage that were not included in the original fatigue damage spectrum*. Maybe someone closer to the CH-46 program can amplify on that subject. I "heard" that is was a GAG ( ground-air-ground cycle ) issue associated with landing loads, but cannot confirm that conclusion. I do recall from having flown the CH-47A early on that one could "plant the rear wheels on a tandem, without it feeling too bad up front. The cockpit doesn't get all of the vertical "G", because the fuselage rotates nose down when the rear wheels make contact.
* At the introduction of a new model, the US Gov't service and the manufacturer assess and agree upon a usage spectrum for the machine. A flight loads survey is then flown to obtain all of the load data associated with that spectrum. The data is good for that spectrum, period.
An small example of what can happen: After the Desert One disaster in Iran, the Army hurriedly formed up the forerunner of the TF-160 group at Ft. Campbell, Ky.
A few months thereafter I got a phone call from a highly concerned GE representative to that unit. ( He had been the GE Rep to Sikorsky during the Blackhawk development and was the best in the business ). He reported that he had sat in the back of a hawk that had just been flown from Nellis AFB ( Las Vegas ) back to Ft Campbell, Ky and the pilots flew it at the TIT limiter, that is at the 30 minute power rating, every minute of the way.
All of this confirms the validity of applying the technolgy now available to installing onboard fatigue damage measurement systems, with bar coded or similar technology applied to each fatigue loaded part/assembly.
Thanks,
John Dixson