JSF Hit By Serious Design Problems
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Shiraz is not bad stuff, you know...
Yes, it could have been argued that the right way to do it would have been to build three aircraft. The Marines could have dispensed with all-round stealth, since their core missions are CAS and defensive counterair, and would have a lighter and simpler aircraft; the AF would probably have ended up with a slightly stealthier, delta-winged design, maybe a bit like a stealthy F-16U; and the Navy would have had a son-of-A-12.
All sorts of parts, procedures and processes would have been common. It would basically look like the Airbus program, with common parts on all sorts of aircraft from the A318 to the A380 and A400M.
Unfortunately, the concept was way too sophisticated for anyone to sell it to the White House or Congress; and the usual Optimism Disease set in, in which if the Pentagon utters a requirement, nobody will say it can't or shouldn't be done.
Yes, it could have been argued that the right way to do it would have been to build three aircraft. The Marines could have dispensed with all-round stealth, since their core missions are CAS and defensive counterair, and would have a lighter and simpler aircraft; the AF would probably have ended up with a slightly stealthier, delta-winged design, maybe a bit like a stealthy F-16U; and the Navy would have had a son-of-A-12.
All sorts of parts, procedures and processes would have been common. It would basically look like the Airbus program, with common parts on all sorts of aircraft from the A318 to the A380 and A400M.
Unfortunately, the concept was way too sophisticated for anyone to sell it to the White House or Congress; and the usual Optimism Disease set in, in which if the Pentagon utters a requirement, nobody will say it can't or shouldn't be done.
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LO,
Your proposed solution is actaully quite close to what the JSF programme IS doing, and you are being a little too hard on the Pentagon.
The 3 JSF variants are quite markedly different in detail, especially the F-35C. A number of changes mark out the F-35A and B as well, although the overall planform and shapes are quite similar. The 3 variants are quite like Airbus, in that they share a number of common components, especially in the Mission Systems area - where the cost savings are significant.
The idea that 3 different types could have been built for the three customers was never a runner. The USN wanted a twin engined aircraft, USAF wanted an F-16 (high G, low cost) and the USMC wanted STOVL. Traditional requirements generation would have meant 3 totally separate aircraft. That had been tried, the Pentagon were looking at the wreckage of a number of failed tactical aircraft programmes and had to do something different.
Some fairly smart people (in the DoD) realised that melding these requirements around STOVL (when CALF became JAST) would restrict the aircraft to a single seat single engine layout and so contain costs. The process of getting to the JSF Joint Operational Requirements Document (JORD) was actually an object lesson in how to do it - and it was certainly not 'uttered by the Pentagon'.
People might not like the look of the plane, but it's a balanced tactical strike aircraft designed to do supersonic STOVL, cat and trap and also land based ops. That's a tough shopping list. I give the US high marks for even attempting it.
Your proposed solution is actaully quite close to what the JSF programme IS doing, and you are being a little too hard on the Pentagon.
The 3 JSF variants are quite markedly different in detail, especially the F-35C. A number of changes mark out the F-35A and B as well, although the overall planform and shapes are quite similar. The 3 variants are quite like Airbus, in that they share a number of common components, especially in the Mission Systems area - where the cost savings are significant.
The idea that 3 different types could have been built for the three customers was never a runner. The USN wanted a twin engined aircraft, USAF wanted an F-16 (high G, low cost) and the USMC wanted STOVL. Traditional requirements generation would have meant 3 totally separate aircraft. That had been tried, the Pentagon were looking at the wreckage of a number of failed tactical aircraft programmes and had to do something different.
Some fairly smart people (in the DoD) realised that melding these requirements around STOVL (when CALF became JAST) would restrict the aircraft to a single seat single engine layout and so contain costs. The process of getting to the JSF Joint Operational Requirements Document (JORD) was actually an object lesson in how to do it - and it was certainly not 'uttered by the Pentagon'.
People might not like the look of the plane, but it's a balanced tactical strike aircraft designed to do supersonic STOVL, cat and trap and also land based ops. That's a tough shopping list. I give the US high marks for even attempting it.
Engines,
Thoughtful and right to a point...
But..
The F-35A and F-35C have this huge hole just behind the cockpit, which is nice to some extent for extra fuel but is not in the right place...
The F-35A and F-35B have two more tails (at least) than they need...
The F-35B has an internal weapons bay (which it won't need all that much) and no internal gun (which arguably it will need)...
And single engine does not necessarily mean cheap.
Thoughtful and right to a point...
But..
The F-35A and F-35C have this huge hole just behind the cockpit, which is nice to some extent for extra fuel but is not in the right place...
The F-35A and F-35B have two more tails (at least) than they need...
The F-35B has an internal weapons bay (which it won't need all that much) and no internal gun (which arguably it will need)...
And single engine does not necessarily mean cheap.
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LO,
To answer your points:
1. The fuel cells on the A and C are fully used - C of G is always a challenge on combat aircraft, and the more fuel you have at the ends the better you can control it - with some clever fuel scheduling.
2. A and B tails are miles smaller then the C's. Same shape, but very different size. IIRC around 35% smaller.
3. B needs an internal weapons bay for the same reasons as the A and C - bay to get the range/payload it needs, and also for LO reasons.
4. Yes, internal vs. external gun is a real poser - one could argue that fitting it only when you need it saves weight and gives more options - and integrating the gun they have chosen is a real challenge - heavy, takes up fuel space, adds drag (big bump) and getting an LO gun muzzle to work is not easy.
5. You are right that single engine doesn't necessarily mean cheap - but single engine and single seat is a powerful way to keep overall weight down - and that is still a major cost driver.
Regards, Engines
To answer your points:
1. The fuel cells on the A and C are fully used - C of G is always a challenge on combat aircraft, and the more fuel you have at the ends the better you can control it - with some clever fuel scheduling.
2. A and B tails are miles smaller then the C's. Same shape, but very different size. IIRC around 35% smaller.
3. B needs an internal weapons bay for the same reasons as the A and C - bay to get the range/payload it needs, and also for LO reasons.
4. Yes, internal vs. external gun is a real poser - one could argue that fitting it only when you need it saves weight and gives more options - and integrating the gun they have chosen is a real challenge - heavy, takes up fuel space, adds drag (big bump) and getting an LO gun muzzle to work is not easy.
5. You are right that single engine doesn't necessarily mean cheap - but single engine and single seat is a powerful way to keep overall weight down - and that is still a major cost driver.
Regards, Engines
