SNECMA high-power ATAR

SNECMA developed the Atar-101 ranging from 1700kgp to 4500kgp. Later, this engine evolved into the Atar-9 series (6000 to 7200 kgp)
But in paralel to that, SNECMA tried to create more powerful engines.
This were
- Atar-103 (3500 kgp)
- Atar-104 Vulcain (4500 kgp)
(both engines at a time when the Atar-101 had only 2000 kgp of thrust!)
- Super Atar (8000 to 12000 kgp)
The problem is : its all I know on this subject! so if someone knows more about these engines...

"Super ATAR" was the engine later known as M-53.

This souns strange because the Super Atar aparently date back from 1958, and the M-53 program was launched only in 1968 (after SNECMA learned turbofans technology with the TF-306 program)

Ok, but the M-53 was also called "Super ATAR".

If you consider that Rolls-Royce Spey, PW TF30, are late 1950s designs, so its concievable that SNECMA worked along these lines. They then had an extended flirtation with the TF30, which finally ended 10 years later (1968). SNECMA considered TF-30 too complex and heavy, and went for a simpler, cheaper, lower technology design (M-53).

IMHO, it's more likely that through the TF104/304/306 development history they learned enough about what not to do that the M53 was a natural follow-on. From what I've seen, they managed to de-bug the basic TF30 faster, and possibly better, than P&W did. It would've been interesting seeing SNECMA teamed with RR/Allison to do a proper afterburning version of the TF41. In 1967 the RR/Allison test articles were already demonstrating 27,000 lbt. in full afterburner.

In the 1970s, Marcel Dassault continually complained about the cost of the Jaguar's Adour turbofan, saying it cost twice the price of an ATAR and gave less thrust. Of course, it was also lighter and much more fuel efficient, which he liked to gloss over. Clearly, he wasn't a fan of turbofans generally, and the French government seems to have disliked the idea of a US powerplant, which sunk the TF30 derivatives.

Concerning the Super Atar, I discovered this engine via many projects... here's a short list
- Single-engine Mirage IV (1956)
- Mirage-V
- Griffon III (plus ramjet)
- Sud Aviation SST project, 1957
And some others I forgot... in every case power was between
8500 kgp and 12000 kgp.

Cocnerning Dassault, the old dwarf (I don't like him very much, whereas I'm a fan of the Mirages) disliked cooperations between countries... Remember the AFVG? for two years, Dassault seems to cooperate with the British on a VG aircraft... the truth was he developped its own VG aircraft, the Mirage G!
And don't forget the F-18 case in the 80's... according to him, buying 15 4000hrs old Hornets would be a threat to the Rafale program! so the aeronavale had to stay with Crusaders until 1999...

The Adour was from Turbomeca, which complete SNECMA on smaller engine (particularly for helicopters).

From what I've seen, they managed to de-bug the basic TF30 faster, and possibly better, than P&W did.
The TF-306 apparently gave 10300 kgp of thrust, Vs 9500 kgp for the Tomcat TF-30
This si quite interesting! There was differents versions of the engine (TF-104, TF-106, TF-306). They were tested on a Mirage III-T (T probably stand for turbofan) which flew on june 1964.
The VTOL Mirage III-V, Mirage F-2 /F-3 and Mirage G were all powered by this engine.

Archibald said:

SNECMA developed the Atar-101 ranging from 1700kgp to 4500kgp. Later, this engine evolved into the Atar-9 series (6000 to 7200 kgp)
But in paralel to that, SNECMA tried to create more powerful engines.
This were
- Atar-103 (3500 kgp)
- Atar-104 Vulcain (4500 kgp)
(both engines at a time when the Atar-101 had only 2000 kgp of thrust!)
- Super Atar (8000 to 12000 kgp)
The problem is : its all I know on this subject! so if someone knows more about these engines...

Click to expand...

If you have interest now too (and no other answer on another aerowebsite since this question), I can search in :
L'ATAR ET TOUS LES AUTRES MOTEURS A REACTION FRANCAIS, Bodemer-Laugier, 1996, Ed. J.D. Reber.
and (try to) translate... But it can be long...

ATAR 103 :

Etude débutée en 1946
Version agrandie de l'ATAR 101, mais avec un compresseur à 9 étages et une turbine à deux étages (température d'entrée 750°C)
Prévu pour une poussée maxi au décollage de 4000 kgp, une consommation spécifique de 1,03kg/kgp/h et une masse estimée de 2000 kg. Maître couple de 1 200 mm, longueur de 4 350 mm. Doit être équipé avec une tuyère à aiguille identique à celle de l'ATAR 101.
Par manque de projets d'avion, l'étude est abandonnée en 1948, mais reprise par la suite sous la forme du Vulcain 104 qui tournera au banc d'essai en mai 1952.

Studies start in 1946.
Greater ATAR 101 with one 9 stages compressor and one 2 stages turbine (entry temperature 750 degrees)
Thrust 4000 kg, weight 2000 kg, length 4350 mm, diameter (?) 1200 mm
Cancelled in 1948 (no plane for this engine in France). But studies used later for the ATAR 104 Vulcain.


VULCAIN (ATAR 104) :

-1951 : des études commencent pour développer un réacteur (sans post combustion) plus puissant que l'ATAR 101 et destiné à des intercepteurs (appareils sans long rayon d'action). Compresseur axial à 8 étages (9 par la suite), turbine à un étage.
-mai 1952 : premier prototype au banc d'essai. Il donne 4 500 kgp.
-mai 1953 : essai de qualification réussi de 15 h à 4500 kgp, mais avec un compresseur de seulement 7 étages.
-décembre 1953 : 5 300 kgp avec le compresseur à 8 étages
-mars 1954 : réussite d'un essai de 15 h à 5 500 kgp
-? : 6 000 kgp avec le compresseur à 9 étages. Mais rupture d'étages de tête.
-fin 1955 : abandon du programme. Les 9 prototypes ont accumulé 400 h d'essai au banc. Le Vulcain est abandonné en raison de la préférence donnée aux bimoteurs type Vautour et en raison de la nécessité de concentrer tous les efforts sur le moteur le plus prometteur, l'ATAR.

Données :
-diamètre maximal et longueur (mesurées avec une règle sur le dessin et calculées grâce à l'échelle indiquée sur le dessin) : environ 1,15 m et environ 3,75 m
-Vulcain 104 A (compresseur 8 étages) : poussée 5 400 kgp; conso spécifique (kg/kgp/h) 1,07; vitesse de rotation : 6 700 tr/min; température amont turbine : 890°C, poids : 1525 kg.
-Vulcain 104 B (compresseur 9 étages) : poussée 6 000 kgp; conso spécifique : 1,05; température amont turbine : 890°C, poids : 1 600 kg.

-1951 studies start for an an interceptor with an jet engine without post combustion. A 8, later 9, stages compressor, an 1 stage turbine.
-may 1952 first prototype with 4 500 kg thrust
-may 1953 works 15 hours with 4 500 kg thrust (but with one 7 stages compressor)
-december 1953 5 300 kg thrust with the 8 stages compressor
-march 1954 works 15 hours with 5 500 kg thrust
-? : 6 000 kg thrust with a 9 stages compressor, but there is technical problems.
-end 1955 : VULCAIN is cancelled, because planes with two jet engines are preferred and because of the most promising ATAR.

-diameter 1 150 mm, length 3 750 mm, weight 1525 kg (104 A with 8 stages compressor) or 1600 kg (104 B with 9 stages compressor)

SUPER ATAR

-1955 : l'état-major oriente les constructeurs vers des études d'avions capables de voler à
mach 3.
-fin 1956 : SNECMA lance l'étude d'un moteur désigné M.26
-mai 1957 : un prototype de démonstration donne 4700 kgp sans réchauffe
-fin 1958 : le moteur complet commence un essai d'endurance à la poussée maxi de 6 400 kgp avec réchauffe
-septembre 1958 : 5200 kgp sans réchauffe pour l'étape suivante : le M.28
-fin 1960 : abandon du projet suite à l'abandon de l'avion pour lequel il était destiné, le Super Griffon mach 3.
4 moteurs d'essai construits. La version définitive devait atteindre 6000 kgp sans réchauffe et
8 500 kgp avec réchauffe, pour un poids de 1 520 kg.

-1955 : french army staff is interested in mach 3 military planes
-end 1956 : SNECMA starts the M.26 study
-may 1957 : a M.26 works with 4 700 kg thrust without PC
-end 1958 : trials for the M.26 for works with 6 400 kg thrust with PC
-september 1958 : the M.28 (evolution of the M.26) works with 5 200 kg thrust without PC
-end 1960 : SUPER ATAR is cancelled because of the cancellation of the Super Griffon plane.
6 000 kg thrust without PC and 8 500 kg thrust with PC and a weight of 1 520 kg were foreseen.


POST SUPER ATAR : (pour/for info)

-1966 : contrat d'étude entre la SNECMA et le Centre de prospective et d'évaluation (CPE) et en accord avec les Avions Marcel Dassault pour des avant-projets de turboréacteurs militaires
mach 3. Plusieurs types de propulseurs sont étudiés, 3 formules sont retenues : TF 306 DS, M45B-2S et M.52 (aucune indication de poussée, dimension ou de poids n'est donnée dans le livre).
Afin de pouvoir garantir des performances intéressantes, une deuxième étape de calcul est lancée. Ces études ont pour but de définir les caractéristiques de base de l'avant-projet M.53

-1966 : three jet engines studies (no data) were chosen for mach 3 military planes studies : TF 306 DS, M45B-2S and M.52. The jet engines studies were later used for the M.53 programme.

That's simply fabulous! Merci beaucoup!

Guys, I think we have found another proof of the existence of a French mach 3 project (the Mega Mirage was the first, now we have alternative engines... and once, the M-45 is there... what an engine!)

Dear Deltafan... was the thrust of the Vulcain obtained with the reheat or not ? Well, if this number was obtained with reheat, the engine seems to offers no advantage towards the Atar-9... except the fact that it was available 3 years before (late 1955 instead of 1958 or so)

That's rise some interesting whatifs... Mirage III-01 (late 1956) powered by the vulcain instead of the Atar-101 would have had a powerful engine (and maybe reach mach 2 ?) in early 1957 instead of October 1958...

The Super Atar is interesting, too! The Mirage IV would have much benefited of its thrust (8500 kgp, when the Atar 9K31 only gave 6700...)

Hi Archibald !

The Vulcain was foreseen and built without reheat... Then, the thrust was obtained without reheat

The similar british Olympus obtained 4 400 kgp without reheat at the beginning (firts trials without plane in 1950) and more than 17 000 kgp with reheat in the Concorde. The Vulcain could have an interesting future if... :-\

Merci!
I understand better why Cuny, in his book, said that "certains regretterent l'abandon du vulcain" talking about the (fabulous) Mirage IVB. In the end, this plane has to be powered by J-75s... which killed the project (no foreign engine on the nuclear deterrent bomber!).

why I don't understand is why the Super Atar was developed when the Vulcain was so promising... were the two engines linked ? I mean, was the Super Atar an improved Vulcain ? ???

Hmmm I think that the Vulcain was for bombers (without reheat) when the Super Atar was more for fighters...

I've found many projects with the super atar along the years... first studies of SST in 1957 (Sud Aviation), Griffon III, Mirage V (not the 1967 aircraft... imagine a scaled-up, naval Mirage III with a tail and... a Super Atar instead of the Atar-9. 3-view available on this forum )

And of course, the improved Grognard (check le Fana of this month ;D) had the Vulcain...

Et enfin... M-26 and M-28 added to the list of SNECMA engines...

Archibald said:

(...)
why I don't understand is why the Super Atar was developed when the Vulcain was so promising... were the two engines linked ? I mean, was the Super Atar an improved Vulcain ? ???
(...)

Click to expand...

I guess that THE problem was always THE problem : money... And the french government must choose... I guess too that the Super Atar was more little (diameter) than the Vulcain because I'm not sure about a link between the two engines (6 000 kgp without reheat for the Vulcain in 1954 or 1955 and only 4 500 kgp without reheat for the M.26 in may 1957).
At the beginning, the Vulcain was foreseen for interceptors. Some years later the diameter of the Vulcain was maybe too large for the french planes projects (and the french money...). And the technical capacities of the Vulcain was maybe enough for mach 2 (with reheat) but not for mach 3. The SUPER ATAR was foreseen at the beginning for mach 3.

The Super Atar had maybe the same diameter as the ATAR 9 : it is said in my book about the Super Atar too :
-built with steel only
-one of the four prototype was built with a 2 stages turbin of the ATAR 9

Money was surely the key of this case! In 1957, due to the algerian war, there was big budgets costs which killed many projects...
Thanks for the infos, that's really what I was seeking for some years now

For comparison, here's a link to the CAEA museum. Good article on the
atar 9K-50 (last variant ever, 7200 kgp after 1965)
http://caea.free.fr/fr/coll/atar9k50.html

Archibald said:

(...)
Thanks for the infos, that's really what I was seeking for some years now

Click to expand...

De rien, you did the same thing for me with the drawing of the Mirage F-3

From a pdf "glanné" on the web, here's the caracteristics of all Atar-101 (pendant qu'on y est...)

Super Atar drawing and information

Thanks Overscan

My french book said 8 500 kgp max for the Super Atar. This book says 22 000 lbs (10 000 kgp i think). From where comes your source ?

Archibald said:

From a pdf "glanné" on the web, here's the caracteristics of all Atar-101 (pendant qu'on y est...)

Click to expand...

From the Safran museum website, here are drawings of the Atar 8B and 9B. Lots more details and articles on their website: www.museesafran.com

…note the CG location marked on the drawings. This rare detail may be relevant for anyone who’s ever dreamt of reengining a Mirage or Etendard! ;-)

Deltafan said:

Hi Archibald !

The Vulcain was foreseen and built without reheat... Then, the thrust was obtained without reheat

The similar british Olympus obtained 4 400 kgp without reheat at the beginning (firts trials without plane in 1950) and more than 17 000 kgp with reheat in the Concorde. The Vulcain could have an interesting future if... :-\

Click to expand...

How large was the Vulcain, was it roughly the same dimensions as an ATAR? would it have fit in the Mirage III airframe? Or was it larger than the ATAR 09?

Yankee_Aviator said:

How large was the Vulcain, was it roughly the same dimensions as an ATAR? would it have fit in the Mirage III airframe? Or was it larger than the ATAR 09?

Click to expand...

A reference to a 1954 low-rated (so presumably developmental) model gives a diameter of 45.6 inches. I wouldn't imagine the final product being substantially smaller. Less than a TF30 so a Mirage IIIT type installation would be doable. Desirable is another matter! It would be short-legged to say the least.

Yankee_Aviator said:

Deltafan said:

Hi Archibald !

The Vulcain was foreseen and built without reheat... Then, the thrust was obtained without reheat

The similar british Olympus obtained 4 400 kgp without reheat at the beginning (firts trials without plane in 1950) and more than 17 000 kgp with reheat in the Concorde. The Vulcain could have an interesting future if... :-\

Click to expand...

How large was the Vulcain, was it roughly the same dimensions as an ATAR? would it have fit in the Mirage III airframe? Or was it larger than the ATAR 09?

Click to expand...

The Vulcain had a larger diameter than the "classic" ATAR 9C of the "classic" Mirage III E/R and 5 :

ATAR 9C : 920/1000 x 5900 mm (with afterburner), 1456 kgs (i don't know why the diameter of the ATAR 9 is sometimes 920 mm and sometimes 1000 mm. I guess it depends on the criteria you take into account. 920 is often mentioned as a "specific" diameter).

VULCAIN 104 : 1160 x 3239 mm (without afterburner), 1525 kgs

But the testbeds Mirage IIIT (one) and Mirage IIIV (two) had french derivatives of the PW TF-30 family (diameter 1240 mm)

overscan (PaulMM) said:

In the 1970s, Marcel Dassault continually complained about the cost of the Jaguar's Adour turbofan, saying it cost twice the price of an ATAR and gave less thrust. Of course, it was also lighter and much more fuel efficient, which he liked to gloss over. Clearly, he wasn't a fan of turbofans generally, and the French government seems to have disliked the idea of a US powerplant, which sunk the TF30 derivatives.

Click to expand...

Does anyone know where there are any Atar 9Cs for sale, in working order with paper work?

Deltafan said:

ATAR 9C : 920/1000 x 5900 mm (with afterburner), 1456 kgs (i don't know why the diameter of the ATAR 9 is sometimes 920 mm and sometimes 1000 mm. I guess it depends on the criteria you take into account. 920 is often mentioned as a "specific" diameter).

Click to expand...

I have specs for a lot of afterburning engines, and many of them have an afterburner module with a significantly larger diameter than the main body of the engine (J79 31.6" & 39.1", J75 43" & 58.5", Spey 201 37.5" & 44", Avon 300 series 41.5" & 44").

So I expect 920mm to be the engine body diameter and 1000mm to be the afterburner module diameter.

I had 35" for the diameter of the non-afterburning Atar 101, and 39" to 40.2" for the largest diameter of the afterburning Atar 9s, but no separate diameter for the Atar 8/9 engine body or the afterburner for the Atar 101G.

You have filled in the engine body diameter for the Atar 8/9s - thanks for that.

@BlackBat242 Or you could refer to the drawings of the Atar 8B and 9C in my post #22: 0.786/0.796m inlet diameter, and 0.858/0.86m diameter for the engine itself (excluding AB section).

I remember measuring the AB section diameter but don’t have the results on hand… however shouldn’t be too hard to count pixels on the drawing.

overscan (PaulMM) said:

In the 1970s, Marcel Dassault continually complained about the cost of the Jaguar's Adour turbofan, saying it cost twice the price of an ATAR and gave less thrust. Of course, it was also lighter and much more fuel efficient, which he liked to gloss over. Clearly, he wasn't a fan of turbofans generally, and the French government seems to have disliked the idea of a US powerplant, which sunk the TF30 derivatives.

Click to expand...

Not entirely Germaine, but that's amusing - the Common Wisdom was that the best way to improve the Thrust / Weight of the Jaguar was to remove 1 engine.