CVF, JSF & MRA4 Problems

[ORAC]

Financial Times: Navy’s new carriers to deploy old aircraft (http://www.ft.com/cms/s/0/a0975762-cec0-11dc-877a-000077b07658.html)

The most powerful ships ever to sail in the Royal Navy will be forced to fly ageing Harrier jets because the replacement F35 Joint Strike Fighters (JSFs) will not be ready in time.

The first of two new aircraft carriers is due to enter service in 2014 and the government had planned to operate Britain’s next generation combat plane, the JSF, from the ships. However, it emerged on Tuesday that the Navy will instead initially have to operate the latest version of the Harrier jump jet, an aircraft first designed several decades ago.

Giving evidence to the Commons’ defence select committee, David Gould, the MoD chief operating officer for equipment and support, said: “We actually do plan to use the [Harrier] GR9 on the first of the carriers. The idea that we will have a carrier’s worth of fully ... equipped JSFs in 2014 is not going to happen.”

The $276bn (£140bn) JSF programme is the most expensive armaments programme ever and Britain is the biggest partner to the US. The UK had originally intended to acquire 150 JSFs but at Tuesday’s hearing General Sir Kevin O’Donoghue, the chief of defence material, admitted that the eventual number would depend on the final price – which has yet to be decided.

Francis Tusa, editor of Defence Analysis, said: “They are admitting there is no cost control from this end of the pond. There is a slight degree of unreality here. JSF costs are going up something like 4 per cent a year. By the time we start laying out money for production, the aircraft will be 30 per cent more expensive than we first budgeted.”

General O’Donoghue also acknowledged that there were likely to be cutbacks or delays to major equipment procurement programmes. “I suspect we will have to [delay or cut some],” he said. Asked when spending was last so tight, he said: “In the late 1970s, we had some challenging times then.”

Separately, Mr Gould identified the Nimrod coastal surveillance aircraft programme as the one where the department is seeing the greatest “cost growth”. The reasons for the continuing cost overruns were due to a problem with pitch on the aircraft, only discovered during the flight trials. It emerged, however, that a similar problem was first identified on an earlier version of aircraft.

Responding to a question on why the government had not yet signed a manufacturing contract with the industry alliance building the two aircraft carriers, Mr Gould said he would be disappointed if a contract had not been signed before the end of March. “The fact that we are going through a review of the [defence procurement] programme of the nature we talked about early on ... it is as serious as you have known it in recent years, yes ... that is not an atmosphere when it is easy to take decisions on big commitments,” he said.

[Wader2]

David Gould, the MoD chief operating officer for equipment and support, said:

Mr Gould identified the Nimrod coastal surveillance aircraft programme as the one where the department is seeing the greatest “cost growth”.

Oh gawd, did he really say coastal :\

[MOA]

'It emerged, however, that a similar problem was first identified on an earlier version of aircraft.'

What problem? Utter bo!!ocks...... :ugh:

[Occasional Aviator]

He could just as well have said "Littoral" - now that this is being extended every year until the whole planet is covered.....

[nav attacking]

Bless Him, It was probably after lunch and he was a little confused. Maybe he was thinking about the Nimrod AEW.:ugh:

After all most people think the MR2 is a sort of AWACs that had some problems in the late 80's.

[GreenKnight121]

Also, is the first CVF still expected to be in commission in 2014, like he says?

I was under the impression that it was looking like 2016 & 2018-2020 now.

[Impiger]

JSF Delayed = CVF Delayed

Surely the CVF should be slipped to meet the JSF in service date and the current CVS extended to compensate. After all that's what we're likely to do with all the other aircraft OSD/ISD gaps. And it seems to make no sense to have a whacking great ship to fly the same air wing that a small ship can manage.:(

[tucumseh]

Wader

"Oh gawd, did he really say coastal"


Have a heart. Every journey begins with a single step. At least he identified Nimrod as an aircraft. That's what comes with being 2 i/c procurement for over a decade.

[Mr-AEO]

Did he really say that because the quoted bit is different. What I mean is, is the error one that the FT has produced? I can't find the minutes from the web at the moment, anyone got the link to the uncorrected minutes from the Defence Select Committee meeting to which the article pertains?

D.G knows his stuff, so i'd be very surprised if he mucked this up.

[mr fish]

i was under the impression the most powerfull navy assets were the trident....oh hang on, a submarine is always called a boat:E

[LowObservable]

Yes, if the first CVF is in service in 2014 there won't be a deck-full of Dave-Bs by any means. In April 2007 the situation was as described here (http://www.jsf.mil/downloads/documents/ANNEX%20A%20Revision_April%202007.pdf).

In fact, given the contract dates are two years prior to delivery, the UK will have exactly nine jets by the end of 2014. By the end of 2016 there will be 18 aircraft, enough to start training. There will not be enough aircraft to support training and IOC - eight aircraft - in 2017.

Richard Beedall has this on his site http://navy-matters.beedall.com/jca1-2.htm.

And discussed on PPrune (http://www.pprune.org/forums/showthread.php?t=279747)too.

On the other hand, this means that the UK lets the jarheads get the bugs out of the aircraft for five years (nominal Marine IOC 2Q12).

Also, note no aircraft for delivery in 2013 (2011 contract year). What this means is that ALL the UK aircraft, except for three in 2011 and 2012 which will never leave the US, I suspect, are eligible to get the more powerful GE/RR engine.

[WhiteOvies]

Nominal IOC for USMC may be 2012 but they have already exteneded the OSD for AV8 out to 2024 - perhaps gives an idea for when they think Dave will be up and running. OSD for GR9 is stated in various places as 2018.

Can't see why it's a problem for Harriers to operate off CVF, you could embark 2 Harrier Sqns at once plus enough Merlin to keep nasty Iranian subs away, plus SK 7s plus a SAR cab or two without the chronic overcrowding currently experienced on CVS.

Alternatively put a decent force of Marines and Junglies to move them on board with a sqn of Harriers to provide CAS topcover and you have a very useful package. With a deck that size the possibilities open to you regards TAG allow the planners much more flex.

[Widger]

Alternatively, scrap JCA and buy Rafale. I know that would not go down well with the light blue but......needs must!

[Ivan Rogov]

Widger, wouldn't that require a cat and trap fit? If so why mess around with an aircraft which may prove expensive and problematic for various reasons, Just get the same as the USN, either reworked F-18 C/Ds (if there are any available) or go with the E/F and even G. Maybe not the newest design but with the development and capability virtually done by the USN already you have immediately useful aircraft, also gives prospects for exchanges pre UK carriers to get up to speed and great interoperability.
If they went that way some E-2s would be useful too :ok:

[LowObservable]

The Hornet C/Ds will be well and truly [cormorant, or long-pile carpet]ed by then. There are four carrier jets in the world. One of them is politically unthinkable, and the MiG-29K is only slightly less so :E. That leaves Dave-C, but eventually US Navy air will take the grocery bag off its head, scream, chew off its own arm and run. Rhinos it is then.

When I said IOC, I meant that's what it says in the schedule. Even if that schedule holds [see simians, airborne, fundament] it will only have Block 1 software, which allows you to frighten the enemy by flying over them.

[Squirrel 41]

LO,

Slightly confused - why would the USN not want Dave-C to work? Surely it is the post-Rhino future of manned USN aviation- unless I've very much missed something.

S41

[Tourist]

http://uk.youtube.com/watch?v=H6h8i8wrajA

[ORAC]

Slightly confused - why would the USN not want Dave-C to work? Surely it is the post-Rhino future of manned USN aviation- unless I've very much missed something. There are several reasons some in the USN aren't enamoured of Dave.

First off it is going to be more expensive than the F-18 and will therefore be bought in more restrictive numbers. There is support for dropping it and buying more E/F/G F-18s instead in the numbers they want.

Then there are those see the EW aspects of the F-18G as being more important than the stealth features of Dave, with some support from the experts who see stealth as a fading advantage as others learn how to defeat it.

There are also those who see Dave B as a threat to the CVN-21 new carrier. The USMC can operate off of the smaller new LHA-R carriers, they are worried that the new carrier will be seen as too vulnerable to NG Chinese weapons and to expensive for littoral operations and will switch orders to Dave B and smaller CVNs at the expense of the bigger carriers. They think if the Dave C is cancelled, so will the USMC Dave B who will have to operate the F-18G for commonality.

You'll find a similar level of support for the RN to go for the F-18 and Cat/Trap on the CVF from some here - who will point out the impetus for Dave B is being driven by the light blue Harrier mafia and not the dark blue naval aviators.....

[John Farley]

Operating site flexibility.

Should be top of any thinking man's military requirements for anything.

Inter-service rivalry.

Totally counterproductive to the national good when it rises above the banter level.

[TEEEJ]

F-35B nozzle test video. 7.74MB

http://attach.high-g.net/attachments/nozzle_check.wmv

The guy observing looks like Professor Denzil Dexter from the Fast Show!

http://uk.youtube.com/watch?v=iZo9zV62sbs

http://uk.youtube.com/watch?v=qsPb8e7USqI

'Dave!'

http://uk.youtube.com/watch?v=dToNQD-Aqsg

[Exrigger]

Tourist, that has made my day, not ever watched the programme but that was funny, more so because, like you said, it does have the ring of probability about it given the current state of affairs.

[Tourist]

The clever thing with them is that their facts are 100% true!

[LowObservable]

JF
Operational flexibility is indeed important, and it's an area of military aviation that is not much exploited, and one way or another we have to deal with anti-access threats.
However, my concern with JSF (I wonder if it would have been shared by that other, much missed JF) is that the joint spec has compromised the flexibility. F-4-sized jets with lots of funny materials on their edges, doors &c are not (I fear) very compatible with soccer fields, industrial parks and random bits of road, or ships under 50000 tons.
That other JF, too, was not a big fan (geddit) of LPLC because of the challenges of STO, with no or limited ability to vector the lift engine thrust, and the consequent inlet momentum drag. JSF-B is in that sense an LPLC. I know that the cascades can vector the fan thrust about 50 degrees aft, but it seems at first sight that the effective area has to decrease in the process.
If JSF-B STOs from a ship at the same T/W as a Harrier, it does so at 50000 pounds or so - the same fuel fraction as a clean F-16, with 2 x 1000 lb bombs and two AMRAAMs.
When the LO requirement was added to STOVL, things got harder to a degree that was not appreciated.
For your respectful consideration,

LO

[John Farley]

LO

Since you addressed your post to me it would be impolite for me not to reply (a notion probably appreciated only by you and I and a handful of other corresondents on this forum)

If you are using operational flexibility as synonym for operating site flexibility then all well and good but I think that the two phrases have very diferent meanings to many people

I don't know what anti-access threats are.

I don't see how the operating site gives a toss about the material of the leading edges or door shapes etc. I think the operating site only knows (and reacts to) exhaust gas velocity and temperature.

As for low observable features compromising a design - well of course that is true but surely that fact applies accross the board to all aircraft and not just STOVL designs?

Your next para "That other JF, too, was not a big fan (geddit) of LPLC because of the challenges of STO, with no or limited ability to vector the lift engine thrust, and the consequent inlet momentum drag" made my brain hurt a tad (easily done these days) as I tried to divine just what you meant.

The lift plus lift cruise types that I know of are not greatly bothered by doing an STO (unless we are considering engine failure) and some were very good at it. I agree that the lift plus cruise ones (very different animals) most certainly did have STO problems but these were related to the need to use moderate alphas in mid transition (to make the wing work) which pointed the lift engines forward and slowed you down again if they were not fitted with enough rearwards tilt capability. Nothing to do with intake momentum drag though.

I don't see the JSF-B as a LPLC aircraft at all. LPLC were a subset of those designs that used a combined power plant for hover. The JSF-B uses an augmented powerplant for hover and is one of three augmented categories

For those that find words even harder than me I will try and post a picture at this point.

http://img.photobucket.com/albums/v145/johnfarley/Thewheel.jpg

Don't know what you are suggesting in your penultimate para. Not arguing the numbers just wonder why you pulled the F-16 out of the hat? It can't play without a suitable runway can it? So we are back to the beginning about the need for operating site flexibility.

As to your last sentence you may be right - I just don't know. What are the elements that were not appreciated?

JF

[LowObservable]

Foz was not a believer in LPLC, because drag increased very rapidly with acceleration, until the lift-jets could be shut down. The result was that LPLCs (in his view) were not as efficient in STO as a Harrier.
In this respect JSF is basically similar to an LPLC, in that the lift fan is similar to a jet. However, it may be possible to play games with transferring thrust from the fan to the main engine, and as I noted there is some vectoring capability on the fan.
As for stealth technology: I'm more concerned about the durability and maintainability of stealth features in a non-pristine environment.
What I can't get an answer on is the STO TOW of Dave-B. If the thrust/weight ratio required for STO is the same as the Harrier, the warload and radius of Dave B will be disappointing to users who are expecting to go much farther and carry more than the Harrier does.

[John Farley]

LO

As you say Foz was not a fan of LPLC but with all respect to his memory that was a quarter of a century ago and a lot of things have changed since those days. He was extremly critical of the Forger (for example) because it "could not do an STO" Well of course we now know that it could and did. It was extremly vulnerable to an engine failure as it needed all three to work - but that is a different issue and not much to do with STO efficiency.

I really do take issue with you over classing the JSF-B as an LPLC though. Not just from the pedantic point of view because it is a single engined aircraft but from the way the control system operates. Varying the thrust between the fan and the rear nozzle is fundemental to the control of the B and with modern FBW capabilities is not at all open to the same doubt as the Forger. Indeed I don't know whether you know but the three engines of the Forger were controlled by a HYDRO-MECHAINICAL computer! A bit like the challenge of doing a hydraulically controlled TV set for the lounge. When their CTP offered me a ride in the Forger way back in '92 I said thanks but no thanks for just that reason - I saw no point in taking the risk (however small) as one would learn nothing of relevance to the future because nobody would ever control an aeroplane again that way today.

Now if the offer had been for the 141 my answer would have been very different but that was not on the table!

I don't know how the STO perf of the B would compare with the Harrier (and if I did this is not really the place for such facts) but it does offer stealth and speed not possible with the Harrier. Given the proclivity of modern weaopons to produce direct hits every time perhaps old fashioned notions of numbers of stores are just that.

I suspect I must know you but there you go.....

JF

[Engines]

John,

What a pleasure to have you on this thread - good manners AND exceptional knowledge - what a pleasant combination! :) Hope I can measure up...

Good to see the AHS 'Wheel of Misfortune' again - I've always thought it was an really clever piece of work, and the very small number of operationally successful designs makes clear just how hard powered lift really is. Makes the Harrier all the more remarkable.

I agree that the F-35B is not an LPLC design - I knew Paul Bevilaqua, who came up with the concept, and he was quite clear that he was aiming at exploiting the thermodynamic and installation advantages of an augmented power plant. Puts the 'up and away' engine at the rear, helps with HGI, and maximises powered efficiency.

LO is right that it's not quite as fexible as a pure vectored thrust design, but it does have a very good STO performance, especially with a ski jump. I can't go into figures here, but it's well above anything a Harrier could do. Think Buccaneer/F-4 cat launch weights and you may be in the right area.

Ski jump STO performance isn't solely dependent on thrust/weight ratio - ramp angle and entry speeds are key determinant, and entry speed depends on deck run as well as T/W.

LO maintenance - very classified, but bear in mind that F-35 is the US's fifth generation LO aircraft - they've learned a lot of lessons about taking care of it along the way.

Best Regards

Engines

[John Farley]

Engines

Thank you for your kind words

Good to hear about the STO stuff.

In my view the simplicity of the straight vectored thrust notion was in 1960 THE way to go because basic mechanical reliability let alone electrics for autostabs etc was nowhere near where things are today. But today we can feel happy with complex systems and reap the performance benefits resulting from the hovering thrust you can get out of a fan (propellor) compared to a pure jet. To say nothing of the HGI issues.

Yours

John

[LowObservable]

JF and Engines,
Thanks for these inputs. I'll have to look at more recent Yak material. The use of a hydromechanical computer (sort of a monster version of a complex pre-DEEC engine control, I imagine) sounds altogether too much fun.
I agree that the nifty bit of the F-35B system is the elimination of non-lifting reaction controls and the use of nozzle area to shift the thrust balance fore and aft. Credit to Paul Bevilaqua for the idea, and credit to many for making it work in practice. Some day we may find out about the classified Lockheed-NASA SSF precursor program and exactly what was found out there.
Weights: nod's as good as a wink to a blind horse, guv.
However, I still predict an entertaining year on JSF, and that the UK will, even if all goes well, be very happy to have set a timetable that allows them to use the F136. Phrases we never hear in STOVL: "It turned out that we didn't need the extra thrust after all."
LO

[Engines]

LO,

You are absolutely right - powered lift aircraft performance depends on two basic attributes:

THRUST and WEIGHT

I believe that the F136 will be key to getting F-35B operational, and I also predict that weight control will be the order of the day for years to come. Just following the maths...

Incidentally, the Sea Harrier flew around quite contentedly with a hydromechanical FCU, developed (I'm told) from the Avon's unit. The Pegasus is still the free world's fastest accelerating and declerating engine, essentially surge free and operating from zero to just over Mach 1 with an open fixed intake and a simple IGV setup plus a couple of blow off valves. And it's British. Makes yer proud, don't it? And that's why Brits are doing a lot of key propulsion related work on the F-35B.

Happy days

Engines

[BEagle]

I was once told that the core of the Pegasus was actually based on the Orpheus.

Is that true?

The fastest accelerating jet engine I've ever heard is whatever powers the Lockheed U-2.....

Back to V/STOL, I've walked past the static VAK191B at the Bremen Airbus site many times. One thing I've always wondered - with 3 engines, where on earth did they also find the space for the 2100 kg of fuel it was supposed to carry.

The 220 nm range must have been thought-provoking!

It must have been fun conducting rapid rolls at high speed with such a challenging B/A ratio.....

[John Farley]

Engines

I am not sure about the Pegasus FCU being based on the Avon unit. That would have been strange as the Pegasus was a Bristol engine (as BEags mentions with the Orpheus connection). The BS 53 (two vectoring nozzles and one fixed) was based on the Orpheus. When Ralph Hooper suggested to Mr BS 53 (Gordon Lewis) that he should bifurcate the jet pipe and put two more nozzles on Gordon designed a new engine to this spec from scratch.

As to the Harrier flying around on a hydro mech fuel system well yes it did for many years but it was the weakest part of the whole powerplant reliability thing and cost us several aircraft before the manual fuel control system mod was added. The MFCS which is a simple pipe from the tank to the burners with a direct tap operated by the throttle handle. There was no control of fuel flow other than that provided by the pilot. No accel control, no altitude control, no IAS control, no JPT control and NO max RPM governor. So if the Pegasus had not been such a forgiving donk it would have been an impossible task.

The Forger hydro mech computer was something else again. It controlled all three engines with the pilot having a single throttle lever and a single thrust direction selector just like the Harrier. It sat under the cockpit floor and was several feet long.

JF

[LowObservable]

<<I believe that the F136 will be key to getting F-35B operational, and I also predict that weight control will be the order of the day for years to come.>>

No company bias here of course...

I agree. The key issue is that the F136 design was frozen after LockMart found that the gremlins had welded several thousand pounds of extra metal into the B when the engineers were on teabreak.

So why does the USAF keep trying to kill the F136?

[ORAC]

So why does the USAF keep trying to kill the F136? Umm, just a guess, but because they're only buying the A version and haven't got a thrust problem operating off 7000ft+ runways, and don't see why they should have to pay for it?

[Engines]

John,

You are probably right - the Avon ancestry of the Peggie FCU was only ever a rumour. Even so, the ability of the engine to operate across a wide range of speeds, heights and inlet conditions without recourse to electrics was always amazing to me.

In my experience, the FCU was pretty reliable, if correctly set up (help from the friendly local RR rep was useful).

LO, Ref the F136:

The key issue is that the F136 design was frozen after LockMart found that the gremlins had welded several thousand pounds of extra metal into the B when the engineers were on teabreak.

Not really - the 136 is still under development, although at an advanced stage. The story about B weight issues is a good one, but can't be repeated on this thread, sadly. Whatever, it wasn't down to gremlins...

Attepmts to kill the 136 are a pure budget drill. There are plenty of people in the US (including USAF specialists) who will, at all costs, wish to avoid having a single souyrce for combat aircraft engines. Politically, GE have great clout and the engine is pretty damn good too. I think it'll survive, and it will be good for all variants if it does.

[LowObservable]

http://www.flightglobal.com/articles/2008/02/04/221306/dod-seeks-more-aircraft-funds-axes-second-f-35-engine.html

I think we all know that this is an accounting gimmick. It allows the DoD to remove money from the projected numbers for JSF procurement and development, in an effort to avoid a Nunn-McCurdy breakout and consequent annual reporting and recertification. (N-McN requires reporting if the projected average unit procurement cost including R&D runs more than a certain percentage above the original projection.)

They know that Congress will put the money back in. They hope. But what happens when GE says "enough of this :mad:, the entire JSF business is a tiny percentage of what we make on civil engines, we're taking our ball and going home" and calls off its lobbyists?

Kind of silly, though.

[Archimedes]

And someone from RR will be on the 'phone to Des Browne, who will in turn call David Millibrand and Gordon, and they, in turn will 'phone someone to protest and issue a veiled hint that without RR input into the engine, we'll seriously consider dropping the JSF, and if the level 1 partner bails out, what will that do for sales, and then....

Getting to be something of an annual ritual now, isn't it? :hmm: