Sud Aviation ECAT: French T-38s and F-5A

Archibald

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I've just unearthed this thread, and it is dynamite alt-history !


Sud Aviation SA-X-125 was a competitor to Breguet 121 (future Jaguar) for ECAT, and lost. What is truly astonishing is its T-38 / F-5A connections.
There, enter a flamboyant and mysterious individual: Paul Stehlin, on Northrop payroll that year 1964.

Stehlin was rather unhappy of Dassault growing monopoly on French combat aircraft: clearly he wanted to balance that through Breguet or the public companies: Nord Aviation and Sud Aviation, to merge into SNIAS / Aérospatiale only in 1970.

So whatif Stehlin, helped by Puget, managed the impossible. https://fr.wikipedia.org/wiki/André_Puget_(militaire)

Together they argue that Nothrop extended N-156 family (T-38 & F-5) are a perfect match for ECAT: supersonic trainer morphing into a LWF combat aircraft.

So why re-invent the wheel ? just propose the British to licence-build Northrop aircraft with Sud Aviation. T-38 / F-5A become SA-X-125.

Against all odds the French & British governments accept the proposal and SA-X-125 are a go, with some twist: 2*Adours or 1*M45G engines (Turboméca & SNECMA with Rolls Royce) are mandatory.

Dassault of course is incensed but they are confident any Mirage can beat the crap of any N-156 derivative.

The French government concedes a Breguet / Aérospatiale alliance is useful to balance Dassault on combat aircraft.

They are not unhappy either with Turboméca playing a similar role related to SNECMA: the latter a public company not able to get out of their Atar monoculture. Turboméca in stark contrast is the Dassault of helicopter turbines and turboprops: a dynamic private company.

Granting them a foothold into SNECMA fiefdom - combat aircraft engines: M45 & Adour - may push SNECMA to get their head out of their ass.

Indeed Turboméca now has Rolls Royce expertise on small turbofans, Adours and M45s. Much more advanced than any Atar... and a direct threat to the future M53.

Notably if the M45G someday pulls an "Adour Mk.106" and gets +30% thrust from 5500 kg: this would put right between 9K50 and M53-2... yet much smaller and lighter and probably with much better sfc.

Licence-build N-156s are also far cheaper than any ECAT.

What do you think ?
 
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The British are intrigued by the N-156 / SA-X-125 potential. Quite inevitably the project starts growing as Jaguar did OTL.
The british are now considering
- a 2*Adour F-5A (Hello Ching Kuo my old friend...)
- a 1*M45G variant (Hello F-20 my old friend...)
- Quite inevitably a 2*M45G variant is also drawn.
Which is essentially an Anglo-French Hornet, ten years before the Hornet... and this worried Dassault a lot, because it is also on Mirage F1 territory.

Drats, now the Anglo-French have between their hands
- T-38s
- F-5As
- a Ching Kuo lookalike
- a F-20 lookalike
- a Hornet lookalike
 
I'll probably get my head bitten off for raining on parades again but here goes. Some random thoughts regarding the British position in no particular order:

  • Budget, double budget, protectionism and role.
  • Your growth variants are not happening anytime before the mid-80s, where I see them being folded into an "EFA Lite".
  • The 1 M45G variant isn't happening. Why would you purchase a F-5/T-38 licence and then tear-up the back half of it?
  • The RAF is still going to be as loathe to operate a supersonic trainer as they were with the Jaguar, especially in a post-73 world.
  • So what does the F-5Adour bring to the table in the light strike/recce role that a Jaguar doesn't?
  • I don't want to try to land a F-5Adour on a rough field even if it was just a fad.
  • What did Hawker Siddeley/BAC do in this timeline to piss off the MoD?
  • A licence still requires US$ at a time we weren't super-popular with the US (Vietnam), already spending limited $ on F-4K/M/F-111K/C-130K and when A-F co-op was the order of the day so why are we not designing in-house(s)?
 
I'll probably get my head bitten off for raining on parades again but here goes. Some random thoughts regarding the British position in no particular order:

  • Budget, double budget, protectionism and role.
  • Your growth variants are not happening anytime before the mid-80s, where I see them being folded into an "EFA Lite".
  • The 1 M45G variant isn't happening. Why would you purchase a F-5/T-38 licence and then tear-up the back half of it?
  • The RAF is still going to be as loathe to operate a supersonic trainer as they were with the Jaguar, especially in a post-73 world.
  • So what does the F-5Adour bring to the table in the light strike/recce role that a Jaguar doesn't?
  • I don't want to try to land a F-5Adour on a rough field even if it was just a fad.
  • What did Hawker Siddeley/BAC do in this timeline to piss off the MoD?
  • A licence still requires US$ at a time we weren't super-popular with the US (Vietnam), already spending limited $ on F-4K/M/F-111K/C-130K and when A-F co-op was the order of the day so why are we not designing in-house(s)?

Oh, please, just be my guest.

I threw a list at the (british) wall to see what stuck. No problem, really.
 
A licence still requires US$ at a time we weren't super-popular with the US (Vietnam)

So much for the "special relationship" but I understand there were "highs" and "lows".
I can't see how it could be worse than *De Gaulle* and the NATO quagmire of 1966.
 
So Bristol backed M.45 is posed against RR RB.153 or RB.172 (full size not Adour).

HSA has HS.1173 which could merge with X-125.
French firm focuses on twin scaled RB.172 (Adour), UK firm focuses on single medium M.45/RB.172.

BAC has P.45, which offers in fixed wing variants a proto-Hornet with Breuget. French focus on scaled down twin, British on the larger.

Dassault has twin small engine F1 derivative....could they find a UK backer? Or could these tie ups be accepted as Dassault has AFVG?
Come the day AFVG dies, Dassault discovers they chose the wrong focus. But only after G4 and G8 lead nowhere.....too late!
 
Hell yes, the P.1173. Hawker very own atempt at some kind of F-5 / N-156.

A SA-X-125 / N-156 / H.1173 tri-partite project between Sud, Northrop and Hawker would be something.
 
I'll probably get my head bitten off for raining on parades again but here goes. Some random thoughts regarding the British position in no particular order:

  • Budget, double budget, protectionism and role.

Can't be worse than French protectionism with Dassault, really. TBFH, the Stehlin / Puget / Sud Aviation proposal has few chance in hell from succeeding in the first place.
Although their main chance is that N-156 and its development fits ECAT like a glove.

  • Your growth variants are not happening anytime before the mid-80s, where I see them being folded into an "EFA Lite"
  • The 1 M45G variant isn't happening. Why would you purchase a F-5/T-38 licence and then tear-up the back half of it?

I mostly agree - I essentially piled up a whole bunch of proposal, throwing them at a wall to see what stuck.

I would say that a twin Adour N-156 / SA-X-125 is the closest from OTL Jaguar, so forget all the other ones.

  • The RAF is still going to be as loathe to operate a supersonic trainer as they were with the Jaguar, especially in a post-73 world.
  • So what does the F-5Adour bring to the table in the light strike/recce role that a Jaguar doesn't?

Massive sales and production from the US side. A whole bunch of T-38s (800 ?) plus all the export F-5A/B by 1964. Should drastically lower the unit price.
The Netherlands bought F-5As in the late 60's, so did Spain and countless other countries. Northrop build more than 2000 N-156s of every kind.
The F-5 is also a much better air defense fighter than Jaguar, also it probably suffers in the strike role. J85s however are old turbojets; Adours should be more economical, being more recent turbofans.

Note that in '73 the Thunderbirds went with T-38s to save fuel compared to the Phantoms they had before. T-38s are rather unexpensive to fly, just ask NASA.

  • I don't want to try to land a F-5Adour on a rough field even if it was just a fad.

I don't understand what you mean here.

  • What did Hawker Siddeley/BAC do in this timeline to piss off the MoD?

P.1173 ? Harriers ?

  • A licence still requires US$ at a time we weren't super-popular with the US (Vietnam), already spending limited $ on F-4K/M/F-111K/C-130K and when A-F co-op was the order of the day so why are we not designing in-house(s)?

Can't be worse than De Gaulle on a ordinary day, NATO stance included.
 
I threw a list at the (british) wall to see what stuck. No problem, really.
Miss, miss, @Archibald threw something at me! :) Seriously though, I wish I could comment on the French aspect with any authority but my comments on the French aeros would essentially be too shallow for meaningful discourse. Something like: Farman ugly, Gerfaut cute.

The Netherlands bought F-5As in the late 60's, so did Spain and countless other countries. Northrop build more than 2000 N-156s of every kind.
Some NATO commonality is very much a plus. I'm not sure it is as significant a draw for the British as other powers but it doesn't hurt.

Note that in '73 the Thunderbirds went with T-38s to save fuel compared to the Phantoms they had before. T-38s are rather unexpensive to fly, just ask NASA.
On this one, I can't see much movement, I'm afraid. A T-38 is cheaper than a Phantom but a subsonic single is cheaper than a T-38. Supersonic trainers were very much the exception worldwide, not the rule. I just can't envisage a compelling justification for RAF supersonic trainers. Outside British spaceplanes (and thus chaseplanes) of course!

I don't want to try to land a F-5Adour on a rough field even if it was just a fad.
The Jaguar had some rough-field capability. Now it fell into disuse or you could even argue it was never of much use to begin with but there was some fuss made of this at the time. A F-5 rough field capability would probably mean either a redesigned wing or some ugly bulged landing-gear doors. It is only a minor point for the Jaguar and against a F-5 but I thought it worthy of note.

Hell yes, the P.1173.
Would avoid the US$ issue, maintain British jobs and importantly institutional knowledge, so ticks a lot of boxes for this side. A French-built example would look killer in Aegean Blue with one of those splendid anniversaire tails!
 
Whenever developing 60s alternates it is always worth remembering that left to its own devices after TSR2 and P1154 die (and probably earlier) what the RAF wants is the F4 off the shelf and as many as it can get.
Politics forces it to accept Harriers (keeping Hawker Siddeley going), Jaguar (keeping BAC going and helping us get in the EEC) and MRCA/Tornado (German money). But if the RAF could have done it would have had an all F4 combat fleet by 1980. Trainers in that case might have been T38s rather than Hawk.
 
In 1963 the Air Staff of the RAF did indeed compare the T-38 against AST.362 which was then being drawn up. Frustratingly I don't have that exact document in front of me at this time.

There was never any serious consideration of it as a possible contender, but it was an inspiration for the sort of trainer performance wanted but the Air Staff wanted cherries on top, AST.362 began as far back as 1961 when the Air Staff began looking at supersonic trainer with a variable-geometry wing (and even V/STOL was seen a desirable feature).

Interestingly, around the same time as the T-38 number-crunching the Air Staff had devised a rule of thumb; 12 years was the maximum time before a trainer became unrepresentative of frontline types based on previous experience of fighter and trainer generations (an assumption the Hawk has smashed ironically).
 
No F4 for MRI is an interim solution.
Jaguar is evolved to this mission.
Reason....costs.
F4K cost excessive. Running costs far far in excess of what it replaced.
Jaguar offers much more cost effective solution.
P.1127 Harrier driven by perception of need for V/STOL.

Supersonic trainer was a fad of the times. Evaluation resulted in cheaper subsonic solutions.
 
In 1963 the Air Staff of the RAF did indeed compare the T-38 against AST.362 which was then being drawn up. Frustratingly I don't have that exact document in front of me at this time.

There was never any serious consideration of it as a possible contender, but it was an inspiration for the sort of trainer performance wanted but the Air Staff wanted cherries on top, AST.362 began as far back as 1961 when the Air Staff began looking at supersonic trainer with a variable-geometry wing (and even V/STOL was seen a desirable feature).

And there was much rejoicing. Yeeeeaaayah !

View: https://www.youtube.com/watch?v=yciX2meIkXI


AST.362, ECAT. And T-38 as a template. Good !

Let's say... anglo-french options

- N-156 lookalikes except slightly enlarged with 2*Adour
- Great Britain: AST.362 use of T-38 as template.
- France: Sud Aviation SA-X-125, also a N-156 clone.

- HS.1173 with 1*M45G

- Breguet 121

- Dassault Cavalier

Engines:
- Rolls Royce
with
- Turboméca for Adour
- SNECMA for M45G

It starts to make some sense...
 
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Supersonic trainer was a fad of the times. Evaluation resulted in cheaper subsonic solutions.
To quote the projected running costs as per 1963:

Cost per hour/annual cost

Chipmunk: £3/ £21,780

Gnat: £84/ £1,267,728

Hunter: £90/ £242,000 (£291,000 if extra airframes acquired)

Jet Provost: £25/ £1,760,000

Jet Provost: £25/ £1,430,000 [I'm presuming one of these figures is for the Mk.3 and the other for Mk.4]

AST.362: £200/ £4,743,000 (£4,260,000 if extra airframes acquired)
 
The RAF wanted the original US built F4 with US engines. It was never going to get it of course.
The RAF really saw no point in VSTOL and had to be forced by Healey to accept P1127RAF instead of more F4s.
AFVG then UKVG was the closest the RAF would accept to a non-F4 solution.
F1-11 confuses the picture as the RAF knows 50 is too small a number for an effective force (ironic in view of the fact that it has to keep 48 Vulcan B2s in service to do the same job)
Jaguar has to be seen in the context of MRCA. The decision to buy strike Jaguars is taken after MRCA becomes the strike aircraft for the 70s. Moving the F4s to replace Lightnings was always planned. More by luck Jaguar (and Buccaneers) turned out to be excellent.
My only point in telling this story here is that the RAF are very clear in their requirement for a tactical fighter. It has to be as close to an F4 as they can get.
 
Looking at Bac P.141, a two Adour / one M45 / two M45 airframe, oriented for air defense first with secondary strike, is the way to go.

A Jaguar done the right way: an AFVG without the VG; a HS.1173 or P.141 or P.146...
I think 2*Adours or 1*M45G may be the right way to go. In that case, Northrop is showing a possible way with N-156T & N-156F, and we are back to ECAT square one... after all the F-5A/E made a nice low-end to the Phantom.
 

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