Geoff_BIts not an arresting wire issue as other aircraft work fine with them as they are, its a design flaw with the F-35C. The wires when tensioned between the spools sit on top of a set single leaf springs parrallel to the flight line to raise the wire slightly above the deck to give the hook a better chance of catching and not gouging the hook into the flight deck.
The problem with the F-35C is that they set the hook axis too close to the main gear as they were focused on the stealth aspect more than carrier operations. So on landing the uncompressed wheels push the wire down at they touch and start to compress as they take the weight of the aircraft, leaving the hook dangling close behind grasping for a wire that hasn’t yet fully sprung back to its correct position.
Nice to see Burbage admit its a design flaw, and whilst he is confident about the hook fixes will work he is hedging his bets i noticed. He stipulated that the aircraft must be perfectly positioned to have the best chance of trapping a wire and that the Stealth requirement forces the hook location and position.
I get the suspicion by the Navy Times tone that whilst the fixes may allow the F-35C to make arrested landings, its trap percentage may fall below the expected KPP 🙁 when it comes to test the system in a couple of months and then on sea trials next year if the land trials are successful.
Now this allows LM to go back to the USN and see if they will accept a higher bolter rate with the revised design or if not will they accept a drop off in the stealth profile to allow for the hook to be positioned further aft. They could probably engineer braces from the bulkhead to move the hook axis further aft but they wouldn’t be able to fully enclose the hook in a stealth housing anymore. To be honest thats probably the better option, sacrificing some of the sideways stealth profile for a safer carrier landing system.
Geoff_BWell I would say that, but it is increasingly obvious that the use of facts around here is clearly frowned upon, if they happen to relate to a project some of the people have a personal issue with…
What the hell, I’ll do it anyway and at least be consistent…
Fact.
The F-35 program has confirmed orders from 7 separate nations all bar one (the UK) of whom are still waiting for their first aircraft to roll off the production line.
Who here can tell me the other fighter project in the world that can better that fact? Which other fighter program has 7 (or more) customers signed up, still waiting for their jets?
Offhand, even the F-16 isn’t doing so well, only having orders for new build aircraft from Greece, Turkey, Iraq, Oman and Morocco that remain unfulfilled.
FACT
How many of those customers signed on with the assumption that they would have their aircraft this decade to replace their legacy aircraft with an affordable and capable aircraft.
Its all very well selling the idea like any Salesman full of BS about the next best thing since sliced bread or your either in the programe or you loose out, but when you fail to deliver the product on time, to budget and too specification then its time to face the music.
Think about it another way there wouldn’t be these discussions if the LM had delivered what they had agreed too, the F-35 was supposed to be better !!!. Afterall it was building the F-16, it had developed and built the F-22, it won the JSF contest by developing & building the X-35’s on time. The schedule laid down for the F-35 wasn’t impossed upon them it was what they agreed too and promised they could deliver. They failed
Geoff_BYeap in the select committee session last July over the GAO report into Carrier Strike switch in the 2010 SDSR they included the money earmarked for the long term replacement Strike Aircraft for the switch from STOVL to CATOBAR Carrier Strike as part of the savings.
The F-35C is in effect the RAF Tornado GR4 replacement as well as the Harrier, and being Carrier capable and qualified the RAF unit(s) would either deploy alongside the embarked FAA unit on CVF or could even deploy on either a US CVN or the French CVN to enforce UK policy as part of a coalition action
Geoff_BThe catapult launches have gone reasonably well from all reports and there have been plenty of video and photos.
I’ll wait and see what the L-M engineers manage to achieve with the redesigns they had already begun to try to resolve or at least sufficiently manage this issue.
There was some suggestion the design and production of the modifications to the tailhook will be completed in April 2012. Considering the magnitude of the work likely to be required if they don’t work, I don’t think that is an unreasonable time to wait to see if the issue can be resolved quickly.
Well they need to test to see if the revised hook and damper will keep the hook down to see how well it catches a wire and the effect that has on the hook, the deck and the wire as excessive ware on any would not be acceptable to the USN.
Then they need to test the arrested landings to test the system works to specification. This so they can get back to testing the effects of the full arrested landing performance and its effect on the aircraft so they can establish the CATOBAR parameters before full Carrier sea trials next year.
The worry is that the fix proves to be insufficient to meet the requirements that finding an acceptable solution will push the program back and increase costs. This is not the best of years to have such an issue arise with the pressing budget concerns.
Geoff_BWould that be 59 attempted arrestments resulting in 3 successes? There may be no connection between catapult launches and arrestments.
What I wonder is whether the very short distance between wheels and hook will pose special problems. I have seen a graphic comparing wheel – hook distances for several carrier capable aircraft. IIRC the F-35C was less than 8 feet while the next nearest was 9+ feet.
No the tests were seperate, the catapult launches would involve accelerating the aircraft using the catapult at various weights and configurations to assess the performance, the behaviour and the impact of a cat launch. The Arrestments indicates stopping the aircraft by use of the arrector hook on a wire to assess the performance on the hook and the impact it has on the aircrafts airframe, systems and pilot as a result of the deceleration.
The more i see that LM statement the more i suspect that is only arrested stops as would have read succesful arrested landings if they had meant landings.
Geoff_BAs of Nov. 3, F-35C carrier variant (CV) jets had executed 59 successful catapult launches and three arrestments.
Well that quote is rather vague to use as proof the arrestor system works. LM have said 59 successfull launches and done three arrestments. It does not say succesful arrestments otherwise they would have said “Succesfully executed 59 launches and 3 arrestments” !!! Also it does not say arrested landings it just says arrestments which can imply rolling ground tests !!!.
As i said earlier if they had perfomed a succesful arrested landing we would have had the video appear showing it and the LM PR machine saying it can land but the hook needs some slight revisions to improve its success rate.
Hopefully the hook revisions will prove to be succesful as relocating the hook will be an interesting engineering exercise that will delay the F-35C part of the program. I’m quite sure they can work out a solution but it will take time to design, test and assess the impact on the changes to the F-35C in terms of its production and performance. How big an impact this has on the development, deliveries, in-service date and cost could prove interesting for the F-35C customers.
Geoff_BSo has the F-35C. 3 successful captures in fact. Despite this it failed one set of tests, obviously the conclusion therefore can and should be drawn that the aircraft is a failure…
:rolleyes:
Ok wheres the photo or video, the successful Steam Catapult Launch and the EMALS launch soon appeared on the web by the PR machine, but strangely no arrested landing has yet been seenl. The QLR said it had failed all 8 attempted traps, so it appears odd to have hearsay mention of 3 sucessful traps and no proof of this event which is not like LM.
I expect they will make the tweaks to the arrestor gear and try again this quarter as they need to know if the tweaks have cured the problem or they face a greater engineering challange to design the hook system.
Geoff_BOh there is. I could find lots of other comparisons, with that and other aircraft. The point being that I have heard a lot of the criticisms before and for other aircraft programmes.
Is F-35 worse? I don’t know, I am not involved enough to judge. I do know that that the internet has magnified all criticism
With reference to the subsequent comments on Peter Goon. I did not know so I googled “Peter Goon F-35”. He does seem to have a history of criticising the programme.
Thats becuase there is alot to be critical of when Lockheed won the JSF prize by getting its X-35 to out perform the Boeing X-32 there was an assumption that the production version would be created in fairly short order by the same team of designers and engineers who mastered the X-35.
Afterall LM had succesfully produced the F-117 Stealth Fighter, the F-22 Raptor so expectations were high on that they could deliver the F-35 on time and within budget expectations. Afterall the basics had all been done in the past 10 years to create the X-35 and all they had to do was create a production version. Add to that their on confidence in using new technology to design and develop the aircraft and their experience of years of building combat aircraft that they new where programmes had gone wrong in the past and they would do better.
Well here we are 10 years later and many much wiser and poorer as a result, and still a long way off seeing capable production aircraft entering service.
Many of the fans will go out of their way to ignore or even deny that anything is amiss with the program and often attempt to discredit those who try question their pride and joy either that or use the excuse that the other earlier 4th generation programs were no better and there is no viable alternative. However the simple fact is the F-35 concept was sold to people that its would be better, it would use the lessons learnt from previous programs to keep to the requirement, the schedule and the budget.
Yes there is no doubt they will eventually resolve all the significant issues with the aircraft by either design, engineeing or by lowering the specifications to margins they can meet. The question is how long this will actually take, what it will cost and what the knock on effect will be to the customers as they attempt to cover the resulting capability gaps as legacy aircraft scheduled for replacemnet by the F-35 have to solder on well into the next decade.
Geoff_BItaly is just talking about cutting back numbers, this could be reducing the requirement, cutting one of the variants, deferring some of the orders to a later date. They may still order the B but only as a replacement for the Harriers leaving Cavour to replace Garribaldi and cut back the airforce requirement to replace Tornado & AMX.
Anyway its too early to tell as yet and has nothing to do with the UK and the F-35C issue although it could have the knock on effect of driving up the unit price slightly.
Geoff_BBut Italy has a new carrier, designed around the F-35B, & which will outlast its complement of Harriers by many years!
In these frugal times it wouldn’t surprise me, they are under serious fiscal pressure and moves similar to the UK’s might be the only way to appease the speculators.
Afterall as long as they stay in the program they can always review the decision in a few years time when the program has settled in to a more effective cost and the fiscal situation is better.
Geoff_BYou wouldn’t happen to have even one single photograph of an F-35C at the correct angle of attack for a carrier landing with the tailhook extended by any chance would you?
I’m told the situation with the tailhook looks different when the nose is pointing up in the air somewhat…
Would that be becuase the successful trials they plaster all over their websites and you-tube and the unsuccesful ones are kept quiet about until somebody else mentions it through formal sources. !
The tailhook is a prime example, rumours abounded about there being an issue with the hook but was dimissed by the fans as false speculation till the QLR came out. You can even see it in this thread where some still denied there was a problem becuase they hadn’t seen it mentioned directly.
The first thing they are trying is to replace the hook point with a different design that sits flush with the deck… the problem here is that this sharper point will wear out the wire more quickly, increasing the chance of the wire breaking in use, and shortening the usable life of the wire if it doesn’t break.
Concurrent with the re-design of the hook point is an increase in the strength of the damper to try to hold the hook down against the deck more completely, so as to keep the point in a better position… this would reduce the damage the hook point does to the wire by reducing the number of “dead-center” impacts of hook point against wire.
Only if these measures don’t work will the hook attachment point be relocated.
Hopefully these will work i suspect thats why they put the EMALS trials forward to free them up for another set of landing trials later in the year. It certainly is not going to be helpful to the variant if more extensive work is required.
Geoff_BCanada ready to buy SAS aircraft.
You mean SAR aircraft
Geoff_BActually the deal signed early last year between France and the UK pretty much agreed to that concept. The Rafale and Hawkeye of the Aeronavale should be fairly common visitors to PoW. Likewise F35C will certainly visit the CdG albeit light loaded due to weight issues.
Its a pretty good deal for both sides really. UK gets French help standing up carrier operations and the French don’t have to go through the hassle of sending their aircraft to the US when CdG is going through an overhaul. It will be very interesting to see how the French E2 Hawkeye fit into QE class operations.
Hammond just signed a similar Carrier Cooperation with Panetta yesterday in the US and we already have US advisors involved in the CATOBAR CVF design along with the embedded FAA crews recieving USN training.
Upto 3 months ago the better relationship with France might well have allowed the possibility of Rafales but with the recent French antics after the Euro fallout i somehow doubt that such a proposal would now be acceotable.
Plus i think the Rafale would be seen as an alternative to the F-35C and would trigger Naval Typhoon debates, where as it would be easier to swallow a SuperHornet lease as a stop gap measure. Thus they can nominally remain in the F-35 program for UK industry sake and then review the situation in the next decade when the capabilities and costs of the F-35C are better known.
Geoff_B[QUOTE=Fedaykin;1841971]Well I think people are jumping to conclusions here people!
I haven’t seen any rumors or official statements about an F35C tailhook issue. If there is an issue we don’t know how much leeway to fix it easily, it might be an anticipated issue with planned fixes or something new that will be pricey…until I see something official then I am regarding this as a fantasy problem dreamed up by one of the many F35 detractors out there! For all we know the tailhook if this is a problem wasn’t adjusted properly and it requires a tweek taking a few minutes…
QUOTE]
Its in the QLR, its a very real and potentially serious problem. Thats why we saw nice Youtube shots of the steam catapult tests and none of the landings as the 8 they tried all failed to catch. Thats how they managed to push the EMALS testing forward 6 months becuase teh aircraft was available and they would need it next year to test a revised hook jaws to see it a quick fix will work.
Tommy Tomlinson actually put a detailed post of the Tailhook problem on one of the USN forums which shows the issues they discovered.
Geoff_BThat part should be trial and error, so it wasn’t until now that it was discovered
With the F-35C they actually used the Suoer Hornet design for the hook as they knew this worked, however they failied to fully take into account it relative location to the main gear and the angle the hook would be catching the wire.
Its hoped the a slight revision to the design of the hook jaws will allow the aircraft to catch a wire and then they can test it to validate if it will be an effective fix. The alternative is to relocate the hook further aft which will have a much greater impact as they will need a sort out the internal structure to cope with the stresses of an arrested landingm before getting to the impact on the aerodynamice, stealth profile and the software.
Hmmn thinking about that this could be the news that has concerned Hammond, as it may well put the development of the F-35C back so we would only be able to get aircraft in sufficient numbers untill the next decade !!!.
I wouldn’t take it as red that the UK is getting cold feet, that will depend on how the F-35C program is going and how the US budget cuts will impact on the overall program. Afterall its quite possible they will defer the F-35C back to allow them to resolve the problem and let the A & B get the teething troubles out of the way.
What may happen if the F-35C is deferred they the UK may well do like the RAAF has done and lease F-18E/Fs so we can work up a Carrier Air group and allow the Tornado to be retired early in the next decade and then replace them with the F-35C as and when they become available, as quite possible the USN may yet focus on the NGAD & X-47B mix for its Carrier Air Groups.
I suspect the lease option may be whats at the back of Hammond’s mind from those comment, they can’t have two toothless terrors awaiting an airgroup, they don’t want to loose out on the BAE part of the F-35 program and they do need to train up a Naval Air Group. It seems to be the best way to keep everybody happy, the RN get a airgroup, BAE still part of the F-35 program, LM dont loose a key customer or partner, the Govt doesnt get stuck with aircraftless aircraft carriers, boeing gets to build more superbugs and the USN gets to train and inter-operate with the RN and help cover any shortfall in their capability as they focus more on the Pacific
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