F-35 Cancelled, then what ?
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With the close links between LM and KAI, the upcoming USAF T-X competition (featuring the KAI/LM T-50) I am not surprised that Korea is leaning towards F-35. It doesn't sound exactly like a free and fair competition but when are these things ever fair?
Regional politics come into play too, a case of keeping up with the Jones (or Japan in this case).
Anything but F-35 would appear to be the wrong answer....
Regional politics come into play too, a case of keeping up with the Jones (or Japan in this case).
Anything but F-35 would appear to be the wrong answer....
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I sent this to Av Wk and they printed it.
Bill Sweetman’s article (A Wimp-Out With Style) makes a good case for South Korea (or anybody else) buying F-15 or Eurofighter aircraft if you are thinking about now. However look 20 years ahead and who would bet them against what the F-35 will be like then?
Bill Sweetman’s article (A Wimp-Out With Style) makes a good case for South Korea (or anybody else) buying F-15 or Eurofighter aircraft if you are thinking about now. However look 20 years ahead and who would bet them against what the F-35 will be like then?
How much more "upgradability" is there in the F-35 than in the other aircraft?
They are all going to be very outdated in 20 years - could the relative difference then seem trivial compared to the new aircraft that could be designed?
Will people not design new and possibly much better aircraft because they're still struggling to absorb the costs of the existing ones?
They are all going to be very outdated in 20 years - could the relative difference then seem trivial compared to the new aircraft that could be designed?
Will people not design new and possibly much better aircraft because they're still struggling to absorb the costs of the existing ones?
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t43562
For many reasons new combat aircraft are not fully capable when they first enter service. 20 years later they start to look seriously useful bits of kit.
Don't take my word for it just look at the history of any type that first entered service since say 1970.
After 40 or so years of service various factors start to make the type look as if it has peaked and so should be replaced before too long. In my view 20 to 40 are likely to be the best operational years.
For many reasons new combat aircraft are not fully capable when they first enter service. 20 years later they start to look seriously useful bits of kit.
Don't take my word for it just look at the history of any type that first entered service since say 1970.
After 40 or so years of service various factors start to make the type look as if it has peaked and so should be replaced before too long. In my view 20 to 40 are likely to be the best operational years.
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Like most jets F-35 is having its capabilities improved over time with the various Block upgrades discussed in the links in the many pages above. The discussion is really whether the 2B configuration is sufficient to give the USMC something useful when they declare IOC.
The USMC and LM say it does, others say it doesn't. For the UK we need to see what standard 17(R) Sqn are going to be testing on our aircraft, how they do during that testing and how the USMC are doing with IOC before we declare IOC.
The USMC and LM say it does, others say it doesn't. For the UK we need to see what standard 17(R) Sqn are going to be testing on our aircraft, how they do during that testing and how the USMC are doing with IOC before we declare IOC.
Ecce Homo! Loquitur...
For many reasons new combat aircraft are not fully capable when they first enter service. 20 years later they start to look seriously useful bits of kit. Don't take my word for it just look at the history of any type that first entered service since say 1970.
Whilst I heartily agree with JF with the development cycle and capability peak for convention fast jets (and ORAC's observation regarding weight growth) I think the true elephant in the room is how long the signature reduction of the F-35 will remain relevant.
Time and technology is already eroding the capability peak of the F-35.
Time and technology is already eroding the capability peak of the F-35.
Then when money is tight (as it always is) we always end up with fleets within fleets. The latter years of the F3 was awash with different mod states causing major headaches. I remember the 'Golden (insert number)'.
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Just this once
I agree re stealth. I don't see how stealth could improve with time as all the other capabilitiess can (except weight) indeed quite the reverse. Given the tremendous compromises caused by providing stealth (aero, structural, systems, maintenance etc to say nothing of cost) I personally would not include it on any wish list of mine - especially for a close support role where operating site flexibity is so useful.
But hey ho when did OR chaps ever not ask for the moon and when did manufacturers not agree a more complex spec if there was more work to be paid for (as well as a natural desire to be at the cutting edge?)
I agree re stealth. I don't see how stealth could improve with time as all the other capabilitiess can (except weight) indeed quite the reverse. Given the tremendous compromises caused by providing stealth (aero, structural, systems, maintenance etc to say nothing of cost) I personally would not include it on any wish list of mine - especially for a close support role where operating site flexibity is so useful.
But hey ho when did OR chaps ever not ask for the moon and when did manufacturers not agree a more complex spec if there was more work to be paid for (as well as a natural desire to be at the cutting edge?)
Through-life growth and adaptation is essential, I agree.
Unfortunately, the F-35B differs from most aircraft in having no margin for weight growth at all, absent a major uprating of not only the engine, but also the lift fan and transmission, which would in turn be constrained by jet effects on the ground. It will also be costly because much of the work will be confined to 400-some B models.
There is also a problem with growing stealth platforms, which is that you can't add capability through pods, or even add antennas or apertures without installing cavities and stealth-compatible radomes/windows. This can be done, but is expensive. Of all the stealth aircraft deployed so far, the F-117 is the only one to have had major upgrades, and that mostly to replace stuff that was initially borrowed from other aircraft.
Now consider that the F-35 architecture is just not the way you'd do things today, being built around two massive central processors. A problem with this is that you can't just port technology over from other programs (newer AESA tech for instance).
And, sure, you can do a lot with software - but S/W and hardware go hand in hand.
Even the modest upgrades to the F-22 (not even AIM-9X yet) have cost a bomb.
As to JTO's point, Raytheon is now preaching that line on-the-record. RCS is locked-in, but detection is progressing quickly.
Unfortunately, the F-35B differs from most aircraft in having no margin for weight growth at all, absent a major uprating of not only the engine, but also the lift fan and transmission, which would in turn be constrained by jet effects on the ground. It will also be costly because much of the work will be confined to 400-some B models.
There is also a problem with growing stealth platforms, which is that you can't add capability through pods, or even add antennas or apertures without installing cavities and stealth-compatible radomes/windows. This can be done, but is expensive. Of all the stealth aircraft deployed so far, the F-117 is the only one to have had major upgrades, and that mostly to replace stuff that was initially borrowed from other aircraft.
Now consider that the F-35 architecture is just not the way you'd do things today, being built around two massive central processors. A problem with this is that you can't just port technology over from other programs (newer AESA tech for instance).
And, sure, you can do a lot with software - but S/W and hardware go hand in hand.
Even the modest upgrades to the F-22 (not even AIM-9X yet) have cost a bomb.
As to JTO's point, Raytheon is now preaching that line on-the-record. RCS is locked-in, but detection is progressing quickly.
Last edited by LowObservable; 18th Nov 2013 at 11:47.
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F-35B WEIGHTY Discussion in OZ Federal Parliament Mar 2012
Anyone have any later references to F-35B weight growth since this one in March 2012? Tah.
F-35A Discussed in Australian Federal Parliament Committee 16 March 2012
House of Representatives Committees ? Parliament of Australia
F-35A Discussed in Australian Federal Parliament Committee 16 March 2012
"...Dr JENSEN: You were talking about weight not being an issue. The problem is that the JSF is already over the 28,948 pounds from the planned amount not to be exceeded. It has already gone over the not-to-exceed weight. There are some problems in the system that have been identified, such as structural issues and so on, that will need to be fixed. That will ultimately result in not only more weight for the direct fix but more weight to make adjustments to the centre of gravity and so on. This is obviously going to adversely affect performance. Is this figured into your calculations for the future at all?
Air Vice Marshall Osley: I do not believe your statement about the F35 being overweight is correct. I do not have the figures here, but the latest estimate that I have is that it is around 90 pounds or so under its maximum weight. The conventional takeoff and landing aircraft last exceeded its allowable weight back in late 2004.
Dr JENSEN: The SWOT analysis?
Air Vice Marshall Osley: Yes. There was a very extensive program that went through and modified many, many parts in the aircraft to reduce the weight. They took several thousand pounds off the aeroplane and it has since been under the not-to-exceed weight and it continues to be under the not-to-exceed weight as of the latest reporting I saw yesterday at the JSF Executive Steering Board.
Dr JENSEN: It has certainly crept up. As I said, my info is that it has already gone over, but anyway—
Air Vice Marshall Osley: That is not correct....
...Senator FAWCETT: Weight margins on the aircraft: in terms of length of useful life of an aircraft, modifications, weight margin and also power available are critical factors, and my reading of available literature indicates that there is a very small weight margin available. Could you comment?
Mr Burbage: Weight is most critical on the short take-off, vertical-landing jet. That is the one that has the toughest requirement for taking off from and landing on small ships. You saw in the movie that we did that, this year. We predict the weight on that airplane to grow at about three per cent per year throughout the rest of the test program and it could grow some more throughout its life if more capability that has substantial weight goes on the airplane. If you look at the STOVL jet and you look at our weight charts, which you are more than welcome to see, we have now gone two years without any weight increase on the STOVL jet, and that is while accommodating engineering changes to the doors, which we have replaced with heavier doors, and other changes that were made to the airplane. We manage the weight very tightly on that airplane—for good reasons, because it needs to be. The other two airplanes are not as sensitive to weight. We are actually probably several thousand pounds away from the first compromise of the performance requirements of those two airplanes. We do, however, manage the weight very tightly on all three airplanes. The metric that we look at is when the weight growth curve levels off, that means your design has stabilised. You are no longer making lots of changes to the design. All three airplanes are now in that level-off phase. The best one is the STOVL where you can go back and see that we have not increased any weight at all in a full two years.
Senator FAWCETT: So having reached that steady state, you are saying you are some thousands of pounds away from—
Mr Burbage: On the non-STOVL jets.
Senator FAWCETT: So the conventional take-off and landing—
Mr Burbage: The key performance requirements that are weight-dependent have large margins still ahead of them. On the STOVL the key performance parameters are much tighter to the weight, because it is more physics than aerodynamics."...
...Dr JENSEN: You said quite explicitly that in the last two years the STOVL version had seen no weight increase.
Mr Burbage: That is correct.
Dr JENSEN: The QLR charts seem to indicate differently. I am referring to the quick look review that was conducted last year.
Mr Burbage: I could show you the chart if I had my computer here. We were actually planning to.
Dr JENSEN: I will show you the chart. I am afraid it is a bit small, but you can see there is January 2010 and there is January 2012. Clearly there has been a weight increase.
Mr Burbage: This increase right here is a ground rule change, not unlike other ground rule changes—when the weight of the electro-optical targeting system was added in, it is just a step function increase. If I bring this down and I measure that point directly back, it goes back two years to intercept that curve there.
CHAIR: Can I just pause there. For the benefit of Hansard, it is impossible to put up on record what you are talking about.
Dr JENSEN: I will get a copy of that chart and provide it so that it can be tabled.
Air Cdre Bentley: That quick look report is a US official use only chart. As such, it has not been released and therefore for us to comment specifically on it is quite out of the ordinary in this type of environment.
Dr JENSEN: Okay. In terms of the STOL weight, would it be true to say that the empty weight now is over NZW?
Mr Burbage: I do not know. I can find out for you. I will take it for the record and provide an answer to you.
Dr JENSEN: If you could take that on notice then.
Mr Burbage: The STOL weight has been very stable and the airplane is meeting all of its performance requirements, so I am not sure what the question is...."
Air Vice Marshall Osley: I do not believe your statement about the F35 being overweight is correct. I do not have the figures here, but the latest estimate that I have is that it is around 90 pounds or so under its maximum weight. The conventional takeoff and landing aircraft last exceeded its allowable weight back in late 2004.
Dr JENSEN: The SWOT analysis?
Air Vice Marshall Osley: Yes. There was a very extensive program that went through and modified many, many parts in the aircraft to reduce the weight. They took several thousand pounds off the aeroplane and it has since been under the not-to-exceed weight and it continues to be under the not-to-exceed weight as of the latest reporting I saw yesterday at the JSF Executive Steering Board.
Dr JENSEN: It has certainly crept up. As I said, my info is that it has already gone over, but anyway—
Air Vice Marshall Osley: That is not correct....
...Senator FAWCETT: Weight margins on the aircraft: in terms of length of useful life of an aircraft, modifications, weight margin and also power available are critical factors, and my reading of available literature indicates that there is a very small weight margin available. Could you comment?
Mr Burbage: Weight is most critical on the short take-off, vertical-landing jet. That is the one that has the toughest requirement for taking off from and landing on small ships. You saw in the movie that we did that, this year. We predict the weight on that airplane to grow at about three per cent per year throughout the rest of the test program and it could grow some more throughout its life if more capability that has substantial weight goes on the airplane. If you look at the STOVL jet and you look at our weight charts, which you are more than welcome to see, we have now gone two years without any weight increase on the STOVL jet, and that is while accommodating engineering changes to the doors, which we have replaced with heavier doors, and other changes that were made to the airplane. We manage the weight very tightly on that airplane—for good reasons, because it needs to be. The other two airplanes are not as sensitive to weight. We are actually probably several thousand pounds away from the first compromise of the performance requirements of those two airplanes. We do, however, manage the weight very tightly on all three airplanes. The metric that we look at is when the weight growth curve levels off, that means your design has stabilised. You are no longer making lots of changes to the design. All three airplanes are now in that level-off phase. The best one is the STOVL where you can go back and see that we have not increased any weight at all in a full two years.
Senator FAWCETT: So having reached that steady state, you are saying you are some thousands of pounds away from—
Mr Burbage: On the non-STOVL jets.
Senator FAWCETT: So the conventional take-off and landing—
Mr Burbage: The key performance requirements that are weight-dependent have large margins still ahead of them. On the STOVL the key performance parameters are much tighter to the weight, because it is more physics than aerodynamics."...
...Dr JENSEN: You said quite explicitly that in the last two years the STOVL version had seen no weight increase.
Mr Burbage: That is correct.
Dr JENSEN: The QLR charts seem to indicate differently. I am referring to the quick look review that was conducted last year.
Mr Burbage: I could show you the chart if I had my computer here. We were actually planning to.
Dr JENSEN: I will show you the chart. I am afraid it is a bit small, but you can see there is January 2010 and there is January 2012. Clearly there has been a weight increase.
Mr Burbage: This increase right here is a ground rule change, not unlike other ground rule changes—when the weight of the electro-optical targeting system was added in, it is just a step function increase. If I bring this down and I measure that point directly back, it goes back two years to intercept that curve there.
CHAIR: Can I just pause there. For the benefit of Hansard, it is impossible to put up on record what you are talking about.
Dr JENSEN: I will get a copy of that chart and provide it so that it can be tabled.
Air Cdre Bentley: That quick look report is a US official use only chart. As such, it has not been released and therefore for us to comment specifically on it is quite out of the ordinary in this type of environment.
Dr JENSEN: Okay. In terms of the STOL weight, would it be true to say that the empty weight now is over NZW?
Mr Burbage: I do not know. I can find out for you. I will take it for the record and provide an answer to you.
Dr JENSEN: If you could take that on notice then.
Mr Burbage: The STOL weight has been very stable and the airplane is meeting all of its performance requirements, so I am not sure what the question is...."
Spaz - That does not appear to show that the STOVL version has any margin for weight increase. The current OEW projection is 2300 pounds over where it was to have been in 2002, with no matching increase in vertical thrust.
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Why is 2002 significant today when a lot has changed in the last decade; and what does 'OEW' mean? (Operating Evaluation Weight is one guess). There was a small thrust increase a few years back on the STOVL engine, that from memory gave an extra 100lbs of thrust vertical - maybe more? I can post a link to that info if required.
Spaz, it's like this:
371 years ago Mr and Mrs Newton had a baby that they named Isaac, and he was really REALLY smart...
The challenge with any vertical landing aircraft is that the landing speed is by definition zero, as is the wing lift. So the total landing weight is less than the thrust, by a margin sufficient to give you some control, and the operating empty weight (OEW) is part of the landing weight. If it goes up the useful load at landing (fuel reserve and weapons) goes down, and there's nowhere to run. I can't tack on a few knots of touchdown speed and use my brakes a bit harder. (That's basically how other fighters, particularly the F-16, have absorbed growth - with bigger brakes.)
None of that has changed in last decade, any more than the laws of gravity. And they did pull out a small vertical thrust increase during the great weight panic of 2004, but not anything like as much as the net weight gain.
371 years ago Mr and Mrs Newton had a baby that they named Isaac, and he was really REALLY smart...
The challenge with any vertical landing aircraft is that the landing speed is by definition zero, as is the wing lift. So the total landing weight is less than the thrust, by a margin sufficient to give you some control, and the operating empty weight (OEW) is part of the landing weight. If it goes up the useful load at landing (fuel reserve and weapons) goes down, and there's nowhere to run. I can't tack on a few knots of touchdown speed and use my brakes a bit harder. (That's basically how other fighters, particularly the F-16, have absorbed growth - with bigger brakes.)
None of that has changed in last decade, any more than the laws of gravity. And they did pull out a small vertical thrust increase during the great weight panic of 2004, but not anything like as much as the net weight gain.
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OEW = Operating Empty Weight - WHO KNEW?
Thanks for defining OEW. How is a 2002 specification - which you have not specified (a link would be nice) for OEW be relevant now in 2013? It is obvious is it not that the F-35B is able to operate in STOVL mode according to KPPs. Where is the issue? If you have up to date figures that define OEW today that would be good. Do you have also the max. vertical landing weight on a specific temp/altitude day also for the F-35B? Humour me some more.
Who knew? Wikipedia does. Pretty common term.
The weight was quoted as 29735 lb in 2002 and if you look at this thread in May 2013 you will find that number cited with a source by someone who is familiar to you.
http://www.pprune.org/military-aircr...ml#post7835852
The current 32300 lb figure is in LM's own Fast Facts.
The issue is not whether the jet can make KPPs but growth margin, of which there is none.
The weight was quoted as 29735 lb in 2002 and if you look at this thread in May 2013 you will find that number cited with a source by someone who is familiar to you.
http://www.pprune.org/military-aircr...ml#post7835852
The current 32300 lb figure is in LM's own Fast Facts.
The issue is not whether the jet can make KPPs but growth margin, of which there is none.
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Still no specification of the 'growth margin'. How about that detail. Thanks. And yes I'm familiar with old figures - what I'm asking for are specific 'uptodate' details rather than the blather given so far about 'growth margin'. And I did not realise WickedPedia was a source as reliable as that. Who'da thunk.
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To be a bit of an anorak, or possibly just being precise, the quoted 32,300 lbs is for an F35B in what configuration?
Is this the weight after the technical refresh and the placement of all the sensors in the airframe or is this the weight now?
Also what has or has not been factored into this weight to reflect the as I understand it need to replace some of the spars with stronger, probably heavier, components. These were the spars made of the lighter than Titanium alloy.
Interesting point on the F16 brakes, I will be interested to see how performing an SRVL with a heavy load effects the brakes.
As has been stated not a lot of room for growth in weight.
Is this the weight after the technical refresh and the placement of all the sensors in the airframe or is this the weight now?
Also what has or has not been factored into this weight to reflect the as I understand it need to replace some of the spars with stronger, probably heavier, components. These were the spars made of the lighter than Titanium alloy.
Interesting point on the F16 brakes, I will be interested to see how performing an SRVL with a heavy load effects the brakes.
As has been stated not a lot of room for growth in weight.
The F-35B is about 300lb below its KPP weight, which isn't very much for growth. However the lift fan and engine are capable of another 10% growth in VLBB, but its not required or requested. The KPP bring back includes 6% engine degradation, apparently.
Rolling landings will/could increase bring back by 2-4000lb.
Indeed. I thought the main growth factor was adding electronics for additional weapons which is impossible with the F-35 as it has to be done with (weightless) software. The other is structural improvements, the recent of which was quite low weight.
Why are they doing it? Why are so many countries so keen on the F-35 despite the issues and costs. Do they know something we don't?
Rolling landings will/could increase bring back by 2-4000lb.
Originally Posted by SpazinBad
Still no specification of the 'growth margin'. How about that detail.
Originally Posted by LO
What is to discuss is how South Korea's entire procurement process was overturned in weeks. Or how the budget for 60 Eagles suddenly covers only 40 super-affordable wonder jets.
The only sure thing here is that this decision has Sweet Fanny Adams to do with economics or operational effectiveness.
The only sure thing here is that this decision has Sweet Fanny Adams to do with economics or operational effectiveness.