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Author Topic: Jaguar  (Read 17004 times)

Offline JFC Fuller

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Re: Jaguar
« Reply #30 on: March 09, 2012, 06:42:44 am »
Alber Ratman,


Thank you for that, that largely confirms the story as we know it. Once the decision was taken for the Phantom (originally acquired to replace the Hunter FGA.9/FR.10) to replace the Lightning in the AD role (instead of using AFVG for that) there was a gap in the ground-attack role, fortuitously the Jaguar had evolved into a heavy aircraft well suited to the role and so it was adopted to replace the now diverted Phantoms. One suspects that the shortfall in aircraft that emerges later in the decade was brought about in part by the failure of the AFVG programme (which in its dying months had become a strike aircraft for the UK) as well as a general recognition that the UK needed more ground-attack/strike aircraft (interestingly planned AD squadron numbers fall from 12 to 9 in total through the 60s whilst the planned strike/recce fleet goes from 18 to 24/23 squadrons).


The Jaguar seems to have emerged as a happy accident for the RAF, but I think that is as close as we can actually get to calling it a "stop-gap", it certainly became one of the most important RAF types in the second part of the Cold War and enjoyed a long and illustrious career- as well as achieving some exports; all round it was a pretty successful type. 

Offline Alber Ratman

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Re: Jaguar
« Reply #31 on: March 09, 2012, 07:21:12 am »
Alber Ratman,


Thank you for that, that largely confirms the story as we know it. Once the decision was taken for the Phantom (originally acquired to replace the Hunter FGA.9/FR.10) to replace the Lightning in the AD role (instead of using AFVG for that) there was a gap in the ground-attack role, fortuitously the Jaguar had evolved into a heavy aircraft well suited to the role and so it was adopted to replace the now diverted Phantoms. One suspects that the shortfall in aircraft that emerges later in the decade was brought about in part by the failure of the AFVG programme (which in its dying months had become a strike aircraft for the UK) as well as a general recognition that the UK needed more ground-attack/strike aircraft (interestingly planned AD squadron numbers fall from 12 to 9 in total through the 60s whilst the planned strike/recce fleet goes from 18 to 24/23 squadrons).


The Jaguar seems to have emerged as a happy accident for the RAF, but I think that is as close as we can actually get to calling it a "stop-gap", it certainly became one of the most important RAF types in the second part of the Cold War and enjoyed a long and illustrious career- as well as achieving some exports; all round it was a pretty successful type.

Exports, it would certainly have achieved more if Dassault hadn't been allowed to buy out Breguet. Jaguar was never their baby and we all know what happened. Shame the big wing Jaguar was never built, but the afterburning Adour never really was allowed to develop as it should have been for the Jaguar in RAF service, especially the 106, handicapped by its 104 core components. Remember, all the post Grandby upgrades planned in 92 were canned due to lack of cash, until the UOR for the GR1Bs was rushed out and it proved its worth in 95. The upgrades for 96/97 were also done on the cheap as SEMs, avoiding BAE as much as possible, although 106 upgrades did require airframe changes that BAE had to be involved in. Happy accident? Maybe, but as it was designed to be a trainer with some close air support capablitity, some accident. However it showed BAC the way to design a rugged and maintainable aeroplane, ideas taken on in Tornado in some respects, even thought that beast is completely different. The Jaguar being available allowed the Phantoms to be re roled to AD, depends on ones take on the matter.

The Kew files make a very interesting read on the project, I'm really looking forward to next week, when I can get my hands on some of the early files, especially the early research and development documents..
« Last Edit: March 09, 2012, 07:32:15 am by Alber Ratman »

Offline northerndancer2000

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Re: Jaguar
« Reply #32 on: March 09, 2012, 07:36:18 pm »
the aircraft did have some vices that wouldn't forgive if you made a mistake. The aircraft would suffer massive trim changes on changes of power setting and with application of flaps/air brakes. True, there were systems set up to negate these by the auto stab system, but pilots I know have told me of times were they have had to put in major inputs to negate the effects. This would be true of many high performance FJs. The aircraft might have been better still with the big wing envisaged by BAE in the 70s, but who knows.



I've always been interested in the Jaguar M.  It was a handsome plane and the land-based Jaguars seemed to have been well-loved and successful.  The reason typically given for the French Marine nationale declining the Jaguar M was its supposed poor single-engine-out handling and throttle response when landing.   To some extent, many of the English-language sources on the Jaguar wondered if these were just excuses for Dassault to open the way to the all-French Super Etandard (esp. considering that the single-engine-out handling of the Super Etandard was going to be a glider).  I believe that the throttle response issues were also present with the land-based prototypes and that these issues were corrected before introduction to service. 


Given your comments about the Jaguar's massive trim changes, could there have been some validity to the French Marine national's complaints about the Jaguar's suitability as a carrier aircraft? 


Offline Alber Ratman

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Re: Jaguar
« Reply #33 on: March 10, 2012, 02:56:12 am »
I can answer your questions about the M as well. Two carrier trials were conducted on the Clemenceau in 1970 and 1971, before PTR modifications were developed and installed to M05, It is totally biased to write that the Entenards engine out landing capability was a negative to that of the Jaguar with two engines when at that time it was impossible to land a Jag on one! SEPECAT were looking to try PTR engines on M05 or reduce drag on the airframe. There was also discussion of changing the wing planform with increased span and thicker chord.. The aircraft in its orignial form just wasn't suitable for carrier operations as it didn't meet the basic USN specifications for carrier landings the French used and certainly the throttle lag was a factor, the Adours just couldn't power up fast enough for overshoots. The French Navy had also found that the angle of the Adours reheat exhaust was damaging the deck and the catapult of the Clemenceau, and more expensive solutions would be required if the aircraft was to have to land with burners on too. The Navy were very anti PTR in the beginning as one could well understand. The aircraft was being modified to M1 standard when the French Government cancelled the order, not doubts with Dassaults lobbying.. But they didn't have to lobby very hard as the Jag just wasn't going to be a brilliant carrier bourne aircraft. M05 was then modified back towards its orignial land based flap settings and prepared for the spining trials in place of A04 for the single seater tests. Video of M05 spinning is found at the beinging of this episode of Test Pilot shown on the BBC in 1986.

 

Cockpit shots are from the E02 two seater trials, it was even more evil than M05 in the spin.. That is not fuel coming out of M05, but smoke from a generator in the engine exhaust to display the spin pattern to the cameras below..

You are right about the land based prototypes having problems with throttle control. The first trial assesment of E01 made it pretty clear that they were unacceptable for service use, both with the original throttle box detents and the engine mechanical cam box later on. Low speed RPM surges were also a problem later on, solved by a sub idle fuel control unit if I am correct. There is a file on Adour development problems at Kew and it's one I intend to get this week. It will propably mention reheat buzz from co planer burners and associated surges, reheat lighting issues, coking of the combustion chambers, the failure of HP compressor drums (that led to S06's demise) and other tribulations.. This is not slagging off the Adour, but it was only the second turbofan that RR had bolted a burner unit onto after the Spey 22R and a lot of the problems in development seem to have been very similar..
« Last Edit: March 10, 2012, 06:03:23 am by Alber Ratman »

Offline Alber Ratman

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Re: Jaguar
« Reply #34 on: March 10, 2012, 06:20:50 am »
I totally concur bar the stiffness.. Wouldn't mind seeing them through. I would suspect that the wing stiffness wasn't an issue in reality.. Laterial control and trim changes were more down to the reaction of the aircraft to flap/slat extension and ineffective spoiler controls. The aircraft had been modified to have a greater inboard flap extension (45 degrees) and less on the outers (23) after the first land based carrier style approach tests. The French did also look to Corsairs and Skyhawks before the Super Etendard was selected. The land based varients never  totally got rid of the trim change problems in service, even with autostab compensation in pitch. Different configs and speeds would produce effects outside the compensation programming range.
« Last Edit: September 08, 2012, 10:14:54 pm by PaulMM »

Offline northerndancer2000

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Re: Jaguar
« Reply #35 on: March 10, 2012, 10:31:51 am »
These posts are why this site is so good.  All too often secondary sources like books and magazine articles are either written for fanboys or as sales pitches.  The plane (missile, ship, etc., etc.) is all too often described as the greatest plane (etc.) since the Wright Flyer and its faults glossed over. 


Thank you very much. 




Offline Hood

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Re: Jaguar
« Reply #36 on: December 08, 2012, 02:20:51 am »
Here is a photo of a model of the Jaguar from Brassey's Annual 1966. It looks like an early version with some differences from the final design.

Offline hesham

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Re: Jaguar
« Reply #37 on: July 01, 2013, 09:02:53 am »
From an old Russian book about Jaguar,


a strange drawings to a single seat and two seat versions.

Offline Jemiba

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Re: Jaguar
« Reply #38 on: July 01, 2013, 11:59:29 am »
It's a drawing of the Breguet 121 ECAP proposal, which was the basis for the
later bi-national Jaguar
(drawing from Aviation Week July 1965)
It takes a long time, before all mistakes are made ...

Offline hesham

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Re: Jaguar
« Reply #39 on: July 01, 2013, 03:18:29 pm »
Yes,that's right my dear Jemiba,


I don't know what happen to my memory.

Offline flateric

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