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Old 3rd Oct 2010, 09:04   #61 (permalink)
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Software problem doesn't sound like it will cause much of a delay. Depending on the nature of the problem with the hinge - and whether it needs a redesign - this could cause another major delay to the F-35B......

F-35s Grounded for Software, Hinge Fixes

Flight testing of all F-35 Joint Strike Fighter variants has been temporarily suspended until software that controls functioning of the engine's three fuel boost pumps is modified, the Pentagon said Oct. 1.

In addition, short takeoff/vertical landing-mode flight testing operations have been prohibited for the F-35B variant after post-flight inspections revealed an issue with the auxiliary inlet door hinge on test aircraft BF-1, said Lockheed Martin spokesman John Kent.

The auxiliary inlet doors, located immediately aft of the lift fan, open to feed additional air to the engine during short takeoffs, vertical landings, hovers and slow-speed flight, Kent said.

The software problem that grounded all three jet variants and led to incorrect sequencing was discovered during laboratory testing, Pentagon spokeswoman Cheryl Irwin said. Left uncorrected, she said, "This could have possibly triggered a shutdown on the three boost pumps, which could potentially cause an engine stall."

Irwin said that such a simultaneous shutdown would be highly unlikely but that "prudence dictated a suspension of operations, temporarily, until the fuel boost pump signal timing was corrected."

Irwin said that update of the software that controls the functioning of the three boost pumps has been developed and that Lockheed engineers plan to complete functional and safety tests prior to installation in the test aircraft. Kent said the update, developed in partnership with fuel system software developer BAE Systems, will be delivered this weekend.

Flight testing will resume Oct. 5, Irwin said.

Kent said F-35B STOVL-mode flights will resume after the root cause has been identified and corrected.......
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Old 3rd Oct 2010, 13:59   #62 (permalink)
 
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Also, so far they have not identified the problem with the hinge, so it's time for diagnosis, redesign or requalify and possibly fabricate and retrofit, which could all take a while.

It's not as if it was obvious, or anything like that, that designing a jet with a whole bunch of doors exposed to rapid airflow, noise and vibration, that have to close to tight tolerances after take-off, and are all flight-critical on landing, might be a challenge.

So much for rigs, modeling and simulation, and tests being purely validation.
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Old 4th Oct 2010, 09:15   #63 (permalink)
 
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It's not as if it was obvious, or anything like that, that designing a jet with a whole bunch of doors exposed to rapid airflow, noise and vibration, that have to close to tight tolerances after take-off, and are all flight-critical on landing, might be a challenge.
Hmm - not good. Wasn't that what a famous VTOL test pilot (and forum poster here) said they might have trouble with....???
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Old 7th Oct 2010, 08:35   #64 (permalink)
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Defense News: DoD Decertifies Lockheed's F-35 Progress Tracker

The Pentagon suspended its certification of Lockheed's system for tracking the progress on the F-35 Joint Strike Fighter and the F-16 Fighting Falcon programs today, underscoring DoD's tough talk about running weapon buys as efficiently as possible.

The department is withdrawing its certification of the company's Earned Value Management System (EVMS) at its Fort Worth, Texas, facility to ensure Lockheed "devotes the needed attention" to revamp its system, which measures progress on the programs, according to a Oct. 5 Pentagon statement. An "internal discussion on what path to now take is ongoing within the department with regard to Lockheed's EVMS," Pentagon spokeswoman Cheryl Irwin said.

Lockheed officials acknowledged that the Pentagon's full review of the restructured F-35 program could change its schedule and cause a corresponding slip in the recertification of its EVMS, according to an Oct. 4 company statement.

The "technical baseline review of the F-35 program … may affect the content and timing of the new F-35 baseline and thus the EVMS re-audit," reads the company statement. The government will determine the schedule of the re-audit." The company's EVMS combines measurements of scope, schedule and cost in a single system to give an "early warning of performance problems," the Lockheed statement reads........
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Old 9th Oct 2010, 08:21   #65 (permalink)
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Evening Standard: David Cameron ‘rules out slash and burn defence cuts’

......Plans to use vertical take-off aircraft on the carriers have been abandoned, however, and cheaper jets that take off and land by using a catapult and wire will be used instead......
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Old 9th Oct 2010, 09:20   #66 (permalink)
 
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Please God, let that be the case. Goodbye RVL, hello unworried sleep.....
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Old 9th Oct 2010, 13:14   #67 (permalink)
 
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If true, this could be a waste of $13M....

Lockheed gets funds for UK F-35 landing modification

...perhaps a last ditch attempt by USN/Lockheed to influence UK decisions?
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Old 9th Oct 2010, 13:38   #68 (permalink)
 
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NaB...

It did occur to me the other day that SRVL has another fun aspect: How long does it take to kill the thrust on that lift system, and how long (consequently) are you gliding along the deck like a hovercraft?

I would guess that you could slam all your IGVs closed as soon as you had weight on wheels, but that might send a powerful shock through the engine. And it's going to take a few seconds for everything to stop spinning and pumping air.
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Old 9th Oct 2010, 14:16   #69 (permalink)
 
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F-35 canx? Anything with carrier capability and a working AESA radar should be considered as a replacement.

That narrows the options somewhat.

Last edited by Willard Whyte; 9th Oct 2010 at 15:30.
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Old 21st Oct 2010, 13:25   #70 (permalink)
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British Shift to F-35C: A Blow to the Beleaguered Joint Strike Fighter 'B' Model


The UK government has decided to shift its Royal Navy purchases of the Joint Strike Fighter (JSF) from the F-35B short take-off and vertical model (STOVL) to the F-35C carrier version, according to news reports. UK Prime Minister David Cameron said the F-35C is “more capable, less expensive and longer-range.”

The decision may have grave implications for the F-35B, which is the version of the JSF most troubled by technical problems and cost growth. The Brits’ decision means only the U.S. Marine Corps and the Italians plan on using the B model.

Fewer overall purchases of F-35Bs may increase the per unit price, weakening the case for the F-35B. According to a troubling August Armed Forces Journal article by Lt. Cmdr. Perry Solomon, “As the first airframe in full-scale production, the F-35B will experience the greatest fluctuation in price if quantities later in the production run are changed.” Solomon also notes that the “F-35B is four years behind schedule, and the per-unit acquisition cost has exceeded $120 million — almost triple the amount envisioned by the Joint Initial Requirements Document for the Joint Strike Fighter.”

Solomon explores some of the myriad problems associated with the F-35B in context of fiscal and international political pressures on the overall JSF program and concludes that “Marine Corps aviation is in danger of collapsing under the weight of its ‘inside the Beltway’ leadership.”

With problems with the F-35B and pressure from the U.S. Navy mounting, the U.S. Marine Corps leadership has recently signaled that it could be open to buying some F-35Cs in lieu of an all-F-35B force.

“So we have these two competing things, and we hold both dear, so what does that mean in context of JSF?” Lt. Gen. George Trautman, deputy commandant for aviation, told Inside the Navy on October 7. “What it means is we need to get the C [carrier] variant flying, we need to get it on the carrier, see what problems it has, what issues it has. Then we need to get the B [STOVL] flying, we need to get it on an L-class [amphibious ship] to see what issues it has, what problems it has, and then we need to get the B variant onto the carrier to see what technical issues occur and what it means for the operation of a carrier.”
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Old 21st Oct 2010, 13:49   #71 (permalink)
 
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I doubt we will ever even get the F35C.

I suspect that the carrier(s) will be delivered well after their announced date. They are being built because it is cheaper to go ahead with them than cancel them - so I can't see HMG putting a lot of pressure on the constructor once the inevitable cost overruns and delays start to build up. Indeed, HMG might well prefer to string out the construction process for as long as possible in order to secure construction jobs.

By the time they are delivered, we will have been without any FW naval aircraft for a very long time - and unless there is an unexpected UOR I can't see HMG itching to rebuild the capacity.

My guess is that we are building the world's biggest and most expensive helicopter carrier.
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Old 22nd Oct 2010, 11:57   #72 (permalink)
 
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As noted on another thread: For the time being the UK plan has to say F-35B, because the official US plan is that there will be no other CV jet in production after 2015, and the Super Hornet starts to retire in 2030.

However, in many ways the UK, RN and Marine JSF plans were propping one another up. The Marines were pointing to the UK and saying "We can't bin the B and leave the UK with two big grey cruise liners" and the USN thought that as long as it was paying for the B it had to go along with the C.

Now, it is becoming legitimate and almost respectable to start asking that old dodgy question - "Why does the Navy's army need its own air force?" - and if the answer is "it's a nice idea but it adds only xx per cent to the capability of a joint force" then Marine TacAir goes, and if that happens the Navy will scrap the C in a picosecond.
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Old 22nd Oct 2010, 12:56   #73 (permalink)
 
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LO, while i don't disagree for a second that the USMC's 'B' buy is now in doubt, i don't believe for a second that the USN is going to shit-can the billions its spent on developing 'C' just so that it can go back to the drawing board and spend more billions to develop an aircraft that looks like JSF, is bound to be even more expensive, and gets into service 10 years later.

as well as being 10 - 15 years behind the USAF in the 'first day of war' business...
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Old 22nd Oct 2010, 17:51   #74 (permalink)
 
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CC - It's not the billions spent developing the C so far. It's the remaining billions on completing and testing the mission systems so that they do some of what the Super Hornet already does, and the billions more that's represented by the difference between the price of 260 Supers and the price of 260 F-35Cs...

Not to mention the comforting feeling of being able to fly 500-600 miles from the carrier with one engine... In a jet that weighs 5,000 pounds more than a Super, with the same thrust... When the Super community is pretty comfortable taking on all comers with the help of Growlers and Harm/AARGM...
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Old 22nd Oct 2010, 18:13   #75 (permalink)
 
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LO, while i can see that being an attractive option for the next decade - SH and its weapons and support being cheap(er) than JSF and able to do what JSF does within the current and projected AD capabilities of its potential adversaries - but do the USN really believe that SH is a platform that can take them to 2040 or so?

no disputing that the USN like SH and think JSF is an awful lot of extra cash for not an awful lot more current combat capability - but amazed that they think SH is still going to be cutting edge in 30 years... (and thinking that if they're right, why the fcuk aren't we ditching JSF and opting for SH!).
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Old 22nd Oct 2010, 20:05   #76 (permalink)
 
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Originally Posted by Trim Stab
I doubt we will ever even get the F35C.

I suspect that the carrier(s) will be delivered well after their announced date. They are being built because it is cheaper to go ahead with them than cancel them - so I can't see HMG putting a lot of pressure on the constructor once the inevitable cost overruns and delays start to build up. Indeed, HMG might well prefer to string out the construction process for as long as possible in order to secure construction jobs.

By the time they are delivered, we will have been without any FW naval aircraft for a very long time - and unless there is an unexpected UOR I can't see HMG itching to rebuild the capacity.

My guess is that we are building the world's biggest and most expensive helicopter carrier.
Sadly..... I have an ominous feeling that F-35C won't ever get ordered either, for the same reasons.
I think the cat n trap decision is to make the 2nd carrier more saleable straight after it's finished.... and thus as you say, we'll end up with a large helo carrier....maybe...unless they find a buyer for that as well.
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Old 23rd Oct 2010, 14:57   #77 (permalink)
 
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I don't think that the Super would be the only Navy platform out to 2040. If F-35C goes, there will be something else, and better because it's not a derivative of the Marine STOVL design.
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Old 23rd Oct 2010, 17:24   #78 (permalink)
 
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I doubt the USN can afford another trip down the A12 route..........

If you look at what a USN CAG can do now, compared to (say) 15 years ago, it's a much reduced beast.

No real long endurance interceptor / OCA asset
No real high payload all-weather strike aircraft
No ASuW / ASW patrol capability
No sigint/land surveillance capability
No organic tanker (with anything like a credible offload capacity)

Yes, the CAG is down to 3-4 types compared to 7-8, but not as a planned or even desired event. Yes, the advent of PGM does to some degree reduce the need for higher payload (although note the Bone & Strike Eagle play well at CAS because of their payload). But overall, it's a lighter-punching more fragile beast.

Most of that force contraction can be laid at the vast amount of money spunked at the A12, without a viable plan B. We can also bemoan the fact that Dave is now an uber-expensive superweapon compared to the original SSF concept.

Nevertheless, lose Dave C and the USN has nothing to bring to the party on the first day vs double-digit SAM and a half-decent IADS.

The Rhino is not a viable plan B for the USN........
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Old 23rd Oct 2010, 19:40   #79 (permalink)
 
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The problem is that the Navy is not seeing a lot of upside to Dave-C. Not the most wonderful LO vehicle, and not a superweapon compared to SSF - just more expensive.

The fact is that at some point we have to figure out how to manage programs or we go out of business. Until then we might as well upgrade what we have, because it seems to be the only thing anyone ever manages to get right.
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Old 2nd Nov 2010, 08:58   #80 (permalink)
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Mainstream US media report signals JSF implosion

For those that cling to the view that all is well with the Joint Strike Fighter, or JSF F-35 project this story of the hour on Bloomberg* may loosen your grip on fantasy.

This is a straight up and down leak to a mainstream news resource that, logically, can be explained as a considered strategy to break the news and desensitize the public and political consequences of project failure well in advance of the major shocks.

It’s where you put a story for those that don’t decipher Aviation Week or read Bill Sweetman on its Ares blog, or Air Power Australia, and who are still being fed crap by journals that trade soft coverage for advertising........

*Pentagon May See Higher F-35 Costs, Delays Up to Three Years

Pentagon’s Favorite Jet Delayed as Costs Rise Yet Again
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