Ravenman if you want to argue please do a better argument than “appeal to authority”. It’s boring and a logical fallacy.
The article I quoted above confirms as an undeniable fact that the F-35 has zero margin for extra heat dissipation, because it can’t function if it’s fuel is too hot and it’s fuel is the coolant. So yeah actually since image / signal processing is my specialty for 20 years I have an insight here. Dr Gilmore is undoubtably a smart man but is his specialty image and signal processing? Note I am not doing an appeal to my authority, I’m telling you what is required in terms of processor power and heat dissipation from my experience to achieve what they have promised in Block3F, feel free to independently do some research and confirm this.
As a factual matter, the fuel is most useful as a coolant when the airplane is on or near the ground. The cavities where the fuel is stored onboard (they aren’t actually tanks in any meaningful use of the term) can dispose of some waste heat to the extent that the ambient air temperature is say, 100 degrees, the fuel may be 85 degrees or whatever, and so on.
Once the plane takes off, ambient temperatures are like zero, so you don’t need a lot of fuel to suck up waste heat. Also, the power used in the aircraft will generally be less at the end of a mission with less fuel, less going fast, perhaps expended weapons, less use of electronic warfare and other features, etc.
I don’t think you actually understand that fallacy at all.
If I say that Dr. Gilmore is an expert on weapons testing, his opinion is highly relevant on whether the F-35 is in trouble is highly relevant. That’s because he is an expert in his field, and is offering views based on his knowledge, experience, and opinions based directly on the subject at hand. Another example of this would be respecting the views of Stephen Hawking on matters of theoretical physics – sure, he might make errors, but in general he’s a credible source on that topic.
An improper appeal to authority is one in which someone who does NOT have any credentials on the matter at hand. Like a software engineer claiming that a military aircraft is completely broken and unfixable.
The article doesn’t say the F-35 has zero margin for heat – you’re inferring something that is not there. The followup article I posted also says that this silly issue has not resulted in any postponed or cancelled sorties, and there’s been no coverage of this dumb fuel issue for two years.
Thanks **Ravenman **for the clarification about the heat and fuel.
Not to hijack the thread, but I wonder, if we were to turn the clock back, knowing what we know today about the JSF, how might the aircraft be designed differently?
Maybe:
Twin engines, to assuage the Navy (and Canadian and Australian) concerns about engine failure over wide, remote, regions?
Larger internal volume to accommodate issues that could arise with overheating or unanticipated equipment or technology that will need more room;
A more spread-out program timetable for testing and evaluation before any production jets are actually produced (maybe an IOC of 2020 for all three military services?)
In a way, it seems that criticism of a program for being behind schedule causes rushing, which then causes errors, and then the same critics demand, 'Why did you rush?"
Really, the biggest issue was that they tried to design a single airframe to do multiple missions for multiple services. If we had it to do over again, THAT is probably the thing that should have been changed. But they felt we could save money (on a cutting edge 5th generation fighter :smack:) by having one design for the air frame that could then use a large percentage of it’s components in common ‘off the shelf’ (once they were designed and developed of course) and save the tax payer in the long run.
There is probably an awful lot of stuff inside the airplane that could smartly be used as common for all three services – the radar is awfully good, the sensor fusion stuff is groundbreaking, the engine is… okay but not great.
But the whole concept of the program at the beginning was that all three airframes would be something like 80% common parts, and the remaining 20% was the stuff that would make the Navy airplane work on carriers, the Marine Corps and the STOVL capability, etc. This general philsophy extended into the early parts of the test program, in which it was planned that if an F-35A could open the flight envelope for aeronautics testing, then the F-35B and F-35C wouldn’t have to repeat all of those tests. They could just do some. Of course, we had to go back and test a lot more of those test points because it didn’t work out that way, and that cost time and money.
So back to the commonality. The numbers are squishy on this, but I’d say its probably closer to 20% parts that are truly common, another 50% that are “cousins”, and the remainder are unique. They really are three different jets. They should have started as three different jets. I bet the Navy would be much more enthusiastic about the F-35C if it was an F-37 with two engines, for example. The Marines would probably end up with roughly the same aircraft, I would think.
These lessons have been learned the hard way. The Navy and the Air Force are now beginning to design a 6th generation fighter, but they are basically doing their own studies and concepts. What they produce will not be the same airplane, nor a variant of the same airplane, to be sure. That’s a better way to go, IMO.
Ah, that explains it. “Death Spiral” is also a specific software industry term, refering to software projects, where it has the meaning:
“A project that will never complete, because the further you get in, the less fixable it becomes”
The situation you describe, where the unit price increases, killing the project, is very rare in software, becasue software is not sold on a cost-plus basis. If anything, in software it would be more common for procurement to increase, as the suppliers make increasingly despeare attempts to save the project by adding more sales/users to cover costs.
Ah, that explains it. “Death Spiral” is also a specific software industry term, refering to software projects, where it has the meaning:
“A project that will never complete, because the further you get in, the less fixable it becomes”
The situation you describe, where the unit price increases, killing the project, is very rare in software, becasue software is not sold on a cost-plus basis. If anything, in software it would be more common for procurement to increase, as the suppliers make increasingly despeare attempts to save the project by adding more sales/users to cover costs.
But the Marines needed a STOVL aircraft for their itty bitty carriers, and a twin-engined aircraft would have been too heavy to develop into a STOVL variant.
And the Marines don’t buy enough aircraft to justify building something just for them - which is why they ended up the Harrier variants last time around.
Erm, I said that the Marines would probably have ended up with a single engine, STOVL aircraft. They might have descoped some features, like the sensor fusion, to control costs - who knows. But I didn’t say that Marines would have a twin engined airplane.
And I don’t concede that Marines cannot afford to develop large programs. The Expeditatiknarg Fighting Vehicle was a 20-year R&D program involving billions of dollars before it was cancelled. The development of the Osprey speaks for itself. The CH-53K (soon to enter testing) and the newer H-1 helos are all rather small programs in terms of production quantities, and to be sure not as difficult a development as a tactical fighter, but are no doubt large development programs that most countries (forget branches of armed forces) could probably not afford on their own.
As far as “death spiral” terminology, even if the term of art has a slightly different meaning for software as compared to defense terminology - I disagree that there’s any evidence that the situation even meets the software definition. There’s no evidence that the schedule delays are worsening or that certain functions are impossible. Every block of software has been delayed (except maybe .5, can’t remember), but it doesn’t seem for example that block 1 was delayed by a year, then 2A by 18 months, then 2B by two years, etc.
The criticism of 3F is whether it will deliver inside the scheduled window for developmental testing, not whether it will deliver at all.
Yeah, but there are large programs, and then there are 5G multirole fighters. The EFV program seems to have cost about $3.3 billion. The Osprey’s program cost is projected at $36 billion after procurement is finished. The F-35 program cost is $1.3 trillion. Let’s say - generously - that a quarter of that is for the STOVL stuff and everything else that is unique to the B airframe, plus acquisition costs. That’s way more than any other Marine program. Even the 8 Wasp-class carriers only seem to have cost about $10 billion in total.
You’re making the same apples to oranges comparison error that always pops up on this issue.
Let’s be very clear: $1.5 trillion has to do with R&D, procurement, AND 50 YEARS OF OPERATIONS of roughly 2,500 F-35 fighters, with roughly 80% of those costs being fuel and maintenance. Of the cost of developing and producing the aircraft, the total bill to DoD is likely in the $330 billion range. Of that, roughly $59 billion is for R&D activities from the beginning of the program and for the next half-century. Of that total R&D bill, the actual amount that the Marine Corps has budgeted for R&D for the F-35 from the start of the program to this very date, is probably along the order of $7 billion – just in very rough numbers. Might be as high as $10 billion, but I’m not sure of that. In contrast, the R&D that has been sunk into the V-22 by the Marine Corps is over $9 billion. That’s a fact.
So to be clear: I’m not saying that the Marine Corps could have developed the F-35 B Lightning II STOVL aircraft for roughly $10 billion. I’m saying that they spent a lot of money on F-35 development, just as they have on development of other big programs, so let’s not pretend that the Marine Corps is broke.
And I’m saying that if they had gone their own way on developing a replacement for the Harrier, perhaps with synergies but not a flawed approach to a “common” airframe design to cooperate with other services, the Marine Corps would very likely have developed something that has the general attributes of what the F-35B turned out to be: STOVL, single engine, more survivable. Other attributes of this fantasy plane surely would have been different – maybe reused a mature engine instead of a whole new F135 development program, maybe more of a low observable instead of very low observable aircraft, and so on.
But let’s not pretend that the Marine Corps is so poor that they couldn’t afford to build a STOVL. If they don’t have a STOVL jet, the big deck amphibs are pointless. The Marine Corps would surely prioritize to make sure that they get something useful out of those ships. Perhaps they would not have invested in such an aggressive new heavy lift helicopter as the CH-53K, which comes with an acquisition pricetag of $35 billion, for example.