CAPFlyer wrote:
The ability to swap the cargo pod was only one option. Where the USAF saw benefit is because they could have several different pods with different configurations and that had a different use in combat - the pods weren't expected to be on both ends. The airplane was expected to drop the pod, take off without it and return to base to get another one for the next delivery. It would allow (for example) several FOBs to be quickly established because you could have a flight of planes bring in the initial setup equipment in the first round of pods, go back empty (and more maneuverable), get the next set and then pick up the first set when they returned as the FOB would then be secured and protected.
What changed was technology - large helicopters were becoming a thing (the Mojave was already in development), as were turboprops and jets weren't far behind. The USAF saw that their needs could be solved in different ways with vertical lift and faster movement instead.
Still a very inflexible design. The perfect world of flying one way trips might seem sensible until you run out of pods. What if the mission is to fly parts/troops/supplies between Dover, Carswell, Biggs, Foster AFBs (Note most are closed now

) picking up and dropping off cargo at each one? "Sorry sir, Can't fly the mission. No pods available".
You are right about large helicopters. Just remember they are Army, not USAF. The USAF already had airplanes that were more efficient and plenty of large lift for the time. The Army's needs are/were different and thus became mainly rotary wing.
A lot of what seemed like good ideas came and went. One of my favorites (as mentioned) was the Fairey Rotodyne. Seemed cool, but H-47s and H-53 evolved as much better machines. The V-22 finally got the role that the Rotodyne wanted. In the end the Rotodyne would have been a flying abortion.
Back to the pods: How often did the CH-54 Tarhe actually utilize them? Rarely, and when used they were very specialized (Electronics, Medical), And more importantly the H-54 could carry a good load slung under the airframe, the C-120 could not, it was just too specialized.
Tracked bogies looked cool too, but were not practical. Even with all of the projects that went nowhere there was still genius involved in the designs. You don't learn if you don't try.
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Had God intended for man to fly behind inline engines, Pratt & Whitney would have made them.
CB
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