I doubt the f-111 mainly because they already tried that and it failed miserably, Nothing to do with Vietnam there. But the usaf was going to get new planes because the ussr was getting new planes im just not sure congress would let the usaf have the F-X as it was originally designed when the f-14 basically fits the bill. And without the competition from the f-15 or f-18 the price might comedown enough for the f-16 not be seen as needed although having only one company building every fighter for the us sounds like a bad idea even if it is grumman. Maybe it would start out as like a f-16xl instead?
The problem though is that to get the F-14 you need Vietnam anyway because it was based on the Navy lessons being learned there just like getting the F-X (F-15) required the same drivers. The original F-X requirement and concept was essentially a lighter, slightly more capable F-111 made heavier due to the included Navy specifications for a heavier armament load. What drove the changed performance specifications that lead to the F-14 and then F-15 was experience and feedback from Vietnam.
In fact without the actual on-going experience in Vietnam the Navy has less of a leg to stand on in Congress with rejecting the F-111B and getting a separate development program supported.
And the F-14 never actually 'fit the bill' for the F-X requirements as presented and certainly not as was modified to arrive at the F-15. Again though without the experience of air combat in Vietnam and the prevailing attitude in Congress and the White House is still going to lean to a single solution for both services which will satisfy none. (And that includes proposals to simply invest in a Phantom III
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Does McNamara still do his systems driven overhaul without the war? If he does, what's the long term outcome?
Likely as it was initiated as a cost savings measure to try and keep escalating defense spending under control. Due to the policy change of a more 'balanced' force and ongoing major development programs such as SSBN and ICBM development and deployment, defense costs had bloomed and the idea was to streamline the process' and eliminate duplication and waste. Hence the number of 'joint' weapons programs and multi-service equipment systems to try and cut down on costs. This went out the window with Vietnam but the idea had already run into both resistance from the services, (see above about the Navy and the F-111B) but also because there were actually differences in the services needs and requirements that could not be adequately met with a single systems. (Such as the Navy's desired "fleet defender" and Air Force interceptor and ground support requirements) But early on the idea looked like it could work and save effort and money and it had Congressional, Administration, Industrial and even some DoD support.
The F-4 was a good example of what the overhaul wanted but also an example of why the idea had problems. The F-4 was in fact very close the needs of all the services for a general purpose aircraft but it wasn't actually really suitable for some of the more 'point' requirements and had to be modified to fit the different roles of the different services. As noted above it could not fit the Navy's required "fleet defender" role for long range defense which required a large radar and large, long range missiles. It had problems with being an interceptor and dog fighter because it lacked some performance, and it had issues with ground attack. But none of those requirements were seen as a problem since doctrine and practice wise these were not seen as a problem.
Vietnam was to prove that these WERE actually problems and that the services "requirements" were indeed sufficient as to require different aircraft to address but without that direct and clear experience it's going to be very much harder to make that argument
So long term the 'trend' would likely continue rather than change.
would this include Project 100,000?
That was literally in response to the increasing requirements for Vietnam so I would guess no
Korea proved the important of air mobility. We can also moved down further to 1944-45, when early helicopters such as the Sikorsky R-4 were used in the China-India-Burma theater of WWII in rescuing downed pilots and also in the Liberation of the Philippines.
Air mobility was one thing but it was the actual doctrine of use that changed due to Vietnam. Whereas helicopter mobility to move men and equipment was part of the doctrine it was in support of the 'standard' field unit as a way of enhancing moving reserves and special units. This changed with Vietnam to become a doctrine in and of itself of Air Mobile Assault where the objective was no longer to take and hold a position but to assault enemy forces and then leave to take them on again somewhere else. (Mind you this wasn't/isn't a 'new' doctrine as there's a reason they are called "Air Cavalry" after all
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But in the context of the conflict that was actually being planned (US-vs-USSR) at the time this wasn't ever going to be as large or complex as it got during Vietnam. It was planned to be an additive not an actual method in and of itself. A lot of this was because it was assumed (and proved out in Vietnam really) that any actual mass movement of men by helicopter would be vulnerable to opposing air power and ground anti-air capability. Which is why it was only really used in large scale in the South and places where the US could gain and hold air-superiority and keep the ground reasonably secure.
In context I'd assume the doctrine and methods will still evolve but they will remain additive and supportive to more standard methods (ground transport and air drop) of deploying into battle.
Without the Vietnam War, perhaps the AC-47 would remain as the primary CAS aircraft until the equivalent of the A-10 can be produced. The threat of Soviet tanks crossing into West Germany was still around, regardless if the Vietnam War occurs or not.
But the AC-47 has no role in such a conflict as it can't actually be a "CAS" asset in even a near-peer battle environment. (Heck the modern AC-130 has issues unless you have air superiority and a reasonably low MANPAD threat) It was made to counter and assist with a certain threat and without Vietnam isn't likely to see a lot of development unless the US gets involved with a different COIN situation.
Randy
