Dassault Etendard Prototypes and Projects

[Jemiba]

Only a question, I just came along :
There were, planned or actually built, twin seat versions of
the Ouragan, the Mystere, Mystere II and IV, the Breguet 1003
Taon and, of course, of the Mirage series, III to 2000, some
intended as trainers, others as night/all-weather fighters.
But still yet, I didn't find a Etendard IV/Super Etendard twin
seater, wich could have looked like the one below.
Any mention anywhere ?

 

[Archibald]

Jemiba, that's a very, very good question! I checked "les avions de combat francais and there's nothng on the subject (I suppose you did, too )

so I asked the question on this cool forum
http://www.checksix-forums.com/forumdisplay.php?f=279

wait and see...

 

[hesham]

My dear Jemiba,

see this; http://avia.russian.ee/air/france/dassault_etendard4.html

 

[Archibald]

Well done, Hesham!

 

[Archibald]

I found a two-seat Etendard but... it was the Etendard VI. Cuny mention that a two seat variant was drawn.
There was three variant of the Etendard
- II (2*Gabizo)
- IV (atar 101)
- VI (Orpheus)

The program was chaotic, the -II was for the AdA and the -VI for Nato.
The -IV was not planned at the beginning!
After the G.91 victory in NATO NBRM-1, the -VI was abandoned. The II was totally underpowered, and the Gabizos proved unreliable.

so the AdA wanted 300 Etendard IVs... before scrapping its order in favor of the Mirage III!
In the end, the French navy bought a navalised Etendard IV.

 

[Jemiba]

Thanks for the clue with Cuny, I hadn't found it ...

And especially for the Aeronavale I would have thought a two seat
variant of interest, as landing on a carrier probably is something
different, than landing on a conventional runway. But ok, there
wasn't a two seater of the Crusader, too ...

 

[Archibald]

The aeronavale solved the problem with a naval Magister, the CM-175 Zephyr.
What an interesting enigma to solve!! If a naval Etendard had been drawn one day, it could be only on three occasions

- two seat land based Etendard IV (AdA)
- two seat Etendard IVM
- two seat super Etendard

I think I'll ask the question to Le Fana de l'aviation, I'm curious...

 

[Archibald]

Done! Wait and see... ;D

 

[hesham]

Hi,

the Dassault Etendard II was a lightweight twin-engined
naval fighter project;
http://www.vectorsite.net/aveten.html

Three prototypes of the Etendard II were ordered as well,
with the first performing its initial flight on 23 July 1956,
well before the first flight of the Etendard VI, with Paul
Bourdier at the controls. The Etendard II looked much like
the Etendard VI, except for a wider fuselage to accommodate
twin Turbomeca Gabizo turbojets, with 9.2 kN (940 kgp / 2,070 lbf)
thrust each, and with no wing dogtooth. The Etendard II was
slightly larger than the Etendard VI, with a length of 12.89
meters (42 feet 4 inches), a span of 8.74 meters (28 feet 8 inches),
and an empty weight of 4,120 kilograms (9,280 pounds).
Armament was to be twin 30 millimeter DEFA cannon in a pack
that could be swapped out with a pack for 32 Matra 68 millimeter
unguided rockets. Not surprisingly, given greater weight than the
Etendard VI but substantially less engine thrust, the Etendard II
was badly underpowered. This deficiency was in principle to be
addressed with an improved Gabizo with afterburning, but the
engine program foundered. Other engine fits were considered,
but the Etendard II was judged unpromising and cancelled in
November 1956. The second and third prototypes were never
built.

 

[Jemiba]

From Jean-Claude Fayer "Prototypes De L'Aviation Francaise 1945 - 1960":

 

[Petrus]

Here is an excerpt from the Flight magazine on what was then called the Mystere 22 (or XXII) (and subsequently became the Etendard II):

The Mystere 22 ordered by the French Government and the Mystere 26 ordered by NATO had virtually identical air-frames, differing only in the power plants installed, the " 22 " having two turbojets located in the fuselage side-by-side with a paired exhaust, and the " 26 " having a single 4,520 lb. thrust Bristol Orpheus B.Or.2 turbojet. The Mystere 22.01 would eventually be powered by two Turbo-meca Gabizo units which would provide a total maximum thrust of 4,840 lb. and a total maximum cruising thrust of 3,880 lb., but initial flight tests were likely to be conducted late 1956 with two 1,640 thrust Dassault M.D.30 (licence-built A.S. Vipers) installed. The Mystere 22-02 would receive either two R.800 or two R.105 Vesta turbojets for comparative trials, and the third machine -the Mystere 22M- would be a deck-landing variant with A- frame arrester hook, long-stroke under-carriage, catapult spools, etc., in which Aeronavale evinced some interest.
A family resemblance to the larger Mystere fighters can be seen in the wing and tail geometry which is common to both Mysteres 22 and 26. The entire nose section of the fuselage, including the cockpit, is identical on both machines. The wing is swept 45° at quarter chord, has a thickness/chord ratio of six per cent and a span of 25 ft. 4 3/4 in. Overall length and height are 37 ft. 2 in. and 12 ft. 5 1/2 in. respectively. Armament comprises a pair of 30mm. French-built DEFA revolver cannon, similar to the British Aden gun, which are combined with the ammunition (120 rounds per gun) in a detachable pack, which can be winched in and out of the fuselage. Avions Marcel Dassault proposed to augment this armament in the case of the Mystere 22 with an internal rocket missile tray. This tray would project the firing and will be expendable so that it will be unnecessary to retract the tray after firing the salvos of rockets. Owing to the use of two turbojets, the Mystere 22 was somewhat heavier than the Mystere 26, the maximum loaded weight of the latter being some 9,000-10,000 pounds. Both machines carried underwing loads comprising two 500 lb. bombs and twelve 3 in. rocket projectiles, or alternative ordnance loads. The Mystere 24, incidentally, was a projected experimental variant of the basic design with a SNECMA Atar 101G engine.

Below you'll find a photo from the Flight magazine, whose caption says it shows the Etendard IV, but my feeling what may be seen in the picture is the Etendard II as well as profile drawings of the Etendard family (a scan from now defunct Polish magazine "Aero").

Best regards,
Piotr

 

[Jemiba]

"...but my feeling what may be seen in the picture is the Etendard II "

Hard to tell, but from size and shape of the intakes and the fact, that there's
a landing light at the nose wheel strut, it could be the Etendard IV, I think

 

[hesham]

Re: Dassault Etendard Prototypes and Projects

Hi,


I renamed this topic,instead off open a new one.


Here is the early drawing to Dassault Etendard VI (formally Mystere XXVI) early and
initial 3-view from Air Pictorial 4/1955 and Avions De Combat I,also the prototype
for original aircraft actually built.

 

[Petrus]

Re: Dassault Etendard Prototypes and Projects

Here is the early drawing to Dassault Etendard VI (formally Mystere XXVI)

If I am not mistaken the drawing of the early variant of Mystere XXVI project comes from Jean Cuny's "Les Avions de Combat Francaise" (which I unfortunately do not have). Elsewhere on the Internet I've found a scan of the page from that book with this drawing. The 'design initiale' of Mystere XXVI seems very interesting: its armament is apparently not mounted in a bay behind its cockpit (as in the actually built prototype) but instead the guns (two cannon?) are placed in its nose. My impression is it seems that the nose could have been detached and replaced with a nose containing recce cameras.
So I wonder what Cuny has written on the early version of the project in his book. Any input would be appreciated.

Regards,
Piotr

 

[VictorXL188]

May I make a contribution to this thread. I attach a picture and GA drawing of the Etendard II as featured in the Fighters A-Z section in the Air International April 1977 issue. The pic on the bottom is the Etendard IV for comparison.

 

[hesham]

May I make a contribution to this thread. I attach a picture and GA drawing of the Etendard II as featured in the Fighters A-Z section in the Air International April 1977 issue. The pic on the bottom is the Etendard IV for comparison.

Thanks.

 

[H_K]

I didn't find a Etendard IV/Super Etendard twin
seater, wich could have looked like the one below.

@Jemiba @Archibald I just got a copy of “La Saga Etendard” which has a detailed sketch of the 2 seater ETD IV... I’ll post it as soon as I can make a good scan.

The 2 seater layout is pretty straightforward:

• The 2nd seat takes the space of the nose wheel well and avionics bay immediately behind the pilot.
• These, in turn, shift to the next tranche back, which originally was intended for a Matra 106 retractable rocket launcher (32x 68mm rockets) or a 300L removable fuel tank (which in the production IVM became a fixed 325L tank)
• The 2-seater retained the 2x 30mm DEFA guns (which are in the next tranche)

The book also has sketches of the Etendard II and VI, which I’ll post in the appropriate threads.

 

[H_K]

@hesham @overscan (PaulMM) Can we rename this topic back to the original “Dassault Etendard Prototypes and Projects”?

It already covers the Etendard II and IV, and I’d like to post more info here on the development of the various II/IV/VI models.

Thanks.

 

[Archibald]

Hmm I remember (even 13 years later !) the Fana answer had been a little... rude, and direct. Maybe that's why I didn't posted it back then.

I would be glad to see those drawings, really.

Even if they are for the Etendard IV rather than its Super Etendard offspring. Truth be told, they were extremely similar.

Since Dassault (shameless !) sale pitch to screw the Skyhawk and Corsair II had been

"Yeah, sure, I can rebuild Etendard IV into Super Etendard". And surely you did... except they were brand new airframes.

Although he did it for the prototypes ! So "contract done".

Whatever, the recipe to turn a 1-seat Etendard IV into a 2-seater, should apply straight to a S.E.

 

[Archibald]

fun story with the word "Etendard" - it means "flag" as in La Marseillaise "l'étendard sanglant est levé..."
(the blood stained flag is raised !)

On the Internet at times some English speakers don't know that étendard = flag (not that I blame them !)

Instead I've seen it written

EN-TEN-DARD

as in entendre "to hear" except it doesn't make any sense.

Now, there is a word "EN-TEN-DEUR" in french, although rarely used. Except in a proverb

"A bon entendeur, salut !"

https://www.linguee.fr/francais-anglais/traduction/à+bon+entendeur.html

Alors, à bon entendeur, salut.	So a word to the wise.
A bon entendeur...!	All the best in your good work!

 

[H_K]

Even if they are for the Etendard IV rather than its Super Etendard offspring. Truth be told, they were extremely similar.

Since Dassault (shameless !) sale pitch to screw the Skyhawk and Corsair II had been

"Yeah, sure, I can rebuild Etendard IV into Super Etendard". And surely you did... except they were brand new airframes.

I’m not sure where this myth originated that the Super Etendard was shamelessly pitched as a simple upgrade but ended up a whole new aircraft.

Neither fact is true. The Super Etendard was exactly what the A-4M was to the A-4E, or the F-4S to the F-4B: an entirely new avionics package and minor engine upgrade in a slightly tweaked airframe.

Contrary to internet lore, the Super Etendard did not get an entirely new wing or airframe. The only changes to the wing were larger leading edge slats and the flaps angle increased from 40 to 47 deg; this reduced approach speed by ~6kts. The airframe stayed largely the same, with increased electrical capacity to support the new avionics.

I suspect that people misread the program’s cost increases as implying a significant departure from the original design, when most likely this merely reflects the hyper-inflation of the 70s and the development cost of the new avionics, which truly were ground breaking in France at the time and were then reused in the Mirage (as documented in the Comaero history).

Of course the peanut gallery critics forget that buying the A-4M would have been just as expensive (and probably much more so) by the time Exocet capability and a French Nav-Attack system with French radar had been added...

 

[Archibald]

I

Even if they are for the Etendard IV rather than its Super Etendard offspring. Truth be told, they were extremely similar.

Since Dassault (shameless !) sale pitch to screw the Skyhawk and Corsair II had been

"Yeah, sure, I can rebuild Etendard IV into Super Etendard". And surely you did... except they were brand new airframes.

the peanut gallery critics

 

[H_K]

Couple of goodies, starting with the specs of the Etendard IV 01 prototype (May 1957 actuals).

Couple of things to note:

• The IV 01 prototype's empty weight was 5,170kg. This apparently included internal gun and rocket armament (2x 30mm + 32x 68mm), so approx. 4,900kg empty equipped.
• The prototype did not have wing tanks, so fuel capacity was limited to 2,150L (really insufficient!)
• The wing was also smaller than the final aircraft, 25.6m2 with 9.04m span (vs. 29m2 with 9.6m span). There were only 2 wing pylons (vs. 4).
• The engine was an Atar 101E with 3,700 kg thrust

There was a proposal for the French Air Force, the Etendard IV A, essentially a de-navalized IV M with the following changes from the IV 01 prototype:

• More powerful Atar 8 engine (4,400 kg thrust)
• Larger 29m2 wing (9.6m span) with 4 pylons
• Greatly increased fuel capacity of 3,300 L (2,650L fuselage + 650L wing). This included replacing the internal rocket launcher with a 330L fuel tank
• Weight: 5,250kg (empty equipped), so a relatively small weight gain of ~+350kg from the prototype

Estimated performance of the Etendard IV A:

• Max speed estimated Mach 1.1 at 11,000m (36,000ft)
• Time to climb of 6min to 13,000m (42,500 ft)
• Combat radius of 243nm (lo-lo) or 442nm at high altitude

This compares to the Etendard IV M proposal at ~5,800kg, which was ~540kg heavier due to navalization requirements and additional avionics like the Aida radar. As a result the IV A was estimated to climb 40 seconds faster to 13,000m (6m vs 6m40s). However, the French Air Force still deemed the IV A to be too compromised by the navalization weight penalties, and never ordered the IV A.

 

[H_K]

More goodies, including 3 operational variants proposed in 1956/57:

• Etendard IV R Reconnaissance (Dec 1956 proposal)
• Etendard IV E two seater (Dec 1956 proposal)
• Etendard IV M (Feb 1957 proposal, updated Jul 1957)

Note the retractable rocket launcher (32x 68mm) on the naval IV M. This is replaced by cameras on the IV R model.
On the 2-seater the 2nd seat displaces the nose wheel and avionics, which move back to replace the rocket launcher.

 

[H_K]

Posted the 2-seater on the other thread:

https://www.secretprojects.co.uk/threads/dassault-etendard-prototypes-and-projects.11138/post-425556

More goodies, including the two-seater proposal:

• Etendard IV R Reconnaissance (Dec 1956 proposal)
• Etendard IV E two seater (Dec 1956 proposal)
• Etendard IV M (Jul 1957 proposal)

Note the retractable rocket launcher (32x 68mm) on the naval IV M. This is replaced by cameras on the IV R model.
On the 2-seater the 2nd seat displaces the nose wheel and avionics, which move back to replace the rocket launcher.

 

[Archibald]

Is there a detailed list somewhere of all the Etendard prototypes, leading to the IV-M ?
I remember finding one with BLC, another one with a british engine (can't remember, Orpheus, Avon ?)
Unlike the Mirage III variants, it is pretty hard to get a complete list.

By 1957 the Armée de l'Air had a lot of planned aircraft types to cover the air defense / interception mission.
A lot of them were axed in 1958
- a last batch of SMB-2 & Etendard IV-A for daylight, low and medium altitude
- a last batch of Vautours for all weather interception
- Trident and/or the ramjet types (Griffon rather than Leduc 022) above 70 000 ft
- SO-4060 / Mirage IV-C heavy / long range fighter

All this got the axe mostly in favor of the multirole Mirage IIIC circa 1958. It was a kind of Sandys / Diefenbaker "budget crunch" moment, but for France, and with far less severe consequences.

 

[H_K]

Is there a detailed list somewhere of all the Etendard prototypes, leading to the IV-M ?
I remember finding one with BLC, another one with a british engine (can't remember, Orpheus, Avon ?)

I'll post more info on the Avon Etendard IVB prototype later. That's the one with BLC.

 

[Archibald]

Many thanks for that !

 

[Jemiba]

Threads merged, as a twin seater isn't a separate project either, I think.

 

[Archibald]

Google traduction of a very good french website.

Etendard IV, de la genèse au prototype (partie 1/3)

L'histoire du Dassault étendard IV de 1955 à 2000. Les numéros 34 & 36 à l'EALC de Lyon Corbas.

translate.google.fr

An Etendard with an Avon... the mind wonder if it was related to the Mirage III-O prototype, same engine, except with an afterburner...

Well I understand better. That bird got an Avon with 2000 pounds thrust + so that it could run a BLC system. In turn, Dassault target seems to have been all these navies with Colossus / Majestic carriers (as listed there)

1942 Design Light Fleet Carrier - Wikipedia

en.wikipedia.org

They tried Australia and India, without success.

Note that the A-4 Skyhawk become - de facto - the unique choice of many navies... or scrapping the carrier.

 

[Archibald]

Folks,

I've just realized that the Super Mystère B1, Mirage IIIO and Etendard IVB all had a RR Avon. It did wonder on all three, and yet none were build. All three types ended with an Atar (SMB-2, Etendard IVM, and RAAF Mirage IIIs)

 

[H_K]

A little more info on the Avon Etendard:

There were actually 2 Avon Etendard proposals. The first Avon proposal was based on the Avon Mk 203 powering the Hunter. It had "similar thrust" to the Atar, which makes sense as the Hunter F.4 had 10,000 lbf (4,500 kgf), so very close to the Atar 8's 9,700 lbf (4,400 kgf).

The Avon Mk 203 installation was expected to be 100kg heavier. The larger diameter required the removal of the rearmost fuel tanks (2x 120L), reducing fuel capacity by ~8% to 3,000L. As a result, there would be no gain in range despite the Avon's lower fuel consumption.

The second Avon proposal was based on the "Avon 51" (11,200 lbf (5,080 kgf), which I believe was a non-reheat variant of the RA28R that equipped the Lightning. This more powerful Avon was ~300kg heavier than the Atar 8 (1,350 vs. 1,050 kg), with 12.5% lower fuel burn at sea level / 350 knots and 4.5% lower fuel burn at 36,000ft / M.085. So the improvement in range, if any, must have been minimal (given the 8% lower internal fuel capacity). However, overall performance improved slightly (Mach 1.07 level speed at 36,000ft, 6m15 climb to 43,000ft).

This 2nd proposal led to the prototype #3 Etendard "IVB" being built, targeting the export market of Colossus/Majestic carrier users (Australia, India, Canada mainly, but perhaps also Brazil, Argentina and the Netherlands).

The other big change with the Etendard IVB was BLC - the blown wing. While this delivered the promised reduction in launch & landing speeds to make the IVB compatible (at least on paper and with tight safety margins) with the 103ft BS4 catapults and Mk13 arrestor wires on Colossus/Majestic class carriers, there was one BIG problem: according to pilots the IVB was "barely controllable" on final approach! Simple reason: when the pilot would reduce the throttle, this would also reduce the bleed air going to the wings, causing a rapid loss of lift.

Dassault's engineers worked on several fixes to make the IVB's throttle response more linear, but it seems like the problem was never fully resolved. Perhaps it could have been with more engineering efforts, but by that point the focus had moved elsewhere. The market opportunity was simply too small: the Australians and Canadians did not have any naval fighter replacement programs (although teams did visit France to look briefly at the IVB). Only an Indian order for 16 IVBs seemed like it might be on the cards, following a test flight by an Indian Navy pilot.

I will post some IVB performance data and carrier take-off/landing speeds next.

 

[kaiserbill]

The second Avon proposal was based on the "Avon 51" (11,200 lbf (5,080 kgf), which I believe was a non-reheat variant of the RA28R that equipped the Lightning. This more powerful Avon was ~300kg heavier than the Atar 8 (1,350 vs. 1,050 kg), with 12.5% lower fuel burn at sea level / 350 knots and 4.5% lower fuel burn at 36,000ft / M.085. So the improvement in range, if any, must have been minimal (given the 8% lower internal fuel capacity).

The weights given are confusing.

The RR Avon 301R that powered the Lightning FMk6 has a listed weight of 1310kg, and this with afterburner fitted. 56.45 kN dry and 76.11 wet.

How would the lighter, less powerful Avon variant above, without an afterburner fitted, be heavier than the Avon 300 with afterburner?

 

[H_K]

The weights given are confusing.

The RR Avon 301R that powered the Lightning FMk6 has a listed weight of 1310kg, and this with afterburner fitted. 56.45 kN dry and 76.11 wet.

How would the lighter, less powerful Avon variant above, without an afterburner fitted, be heavier than the Avon 300 with afterburner?

The weight you are quoting most likely doesn’t include the afterburner.

It is known that the Avon RB 146 installation in the Mirage IIIO increased weight by 640lbs, a similar increase as I quoted above. The Atar 9C weights 1,450kg with afterburner, so by extension an Avon 300 with reheat should weigh ~1,750kg.

 

[H_K]

I will post some IVB performance data and carrier take-off/landing speeds next

Belatedly coming back to this topic. Here are the Etendard IVB’s performance charts and carrier suitability info.

Still digesting the implications, but I think these charts confirm that the IVB was very marginal for launches from a Majestic class carrier with BS4 catapult:

- The MTOW of 22,000lb (10,000kg) in tropical conditions/zero wind would have been too low for a useful payload/range capability

- Weights seem very optimistic... Dassault quoted 21,000lb (9,500kg) with 2x 1,000lb bombs, which implies an empty equipped weight of ~13,500lb (6,000kg). This is the same as an IVM stripped of its internal gun... even though the IVB should be heavier with the added weight of the blown wing and heavier Avon engine.

- Likewise the “normal landing weight” of 14,500-15,500lb (6,600-7,000kg) seems way too low compared to the IVM’s normal landing weight of ~7,500kg.

 

[H_K]

Here is an excerpt from the Flight magazine on what was then called the Mystere 22 (or XXII) (and subsequently became the Etendard II):

The Mystere 22 ordered by the French Government and the Mystere 26 ordered by NATO had virtually identical air-frames, differing only in the power plants installed, the " 22 " having two turbojets located in the fuselage side-by-side with a paired exhaust, and the " 26 " having a single 4,520 lb. thrust Bristol Orpheus B.Or.2 turbojet. The Mystere 22.01 would eventually be powered by two Turbo-meca Gabizo units which would provide a total maximum thrust of 4,840 lb. and a total maximum cruising thrust of 3,880 lb.

Back to the beginning of the Etendard story in 1955/56... I now have drawings and detailed specs of the 3 Mystere XXII variants mentioned above. Fascinating to see the evolution of this 1950s design in such detail.

Here's the first set of Mystere XXII drawings... I'll post detailed characteristics later:

1. Mystere XXII (Jan 1955): Powered by 2 Gabizo non-afterburning turbojets (1,100kgf each). Early drawing with weird sweeping wingtips and tail fin

2. Mystere XXII #01 (Feb 1956): Actual prototype, with normal wingtips & tail fin.

3. Mystere XXII #02 (May 1956): Never flew. The 2 Gabizos are now afterburning (1,530kgf each) providing a greatly increased climb rate. Fuel capacity increased from 1,600L to 1,800L (larger fuel tank in center wing box), larger tail section to fit the afterburner jet pipes, cockpit moved slightly forward to fit more radio/nav equipment.

4. Mystere XXII Marine (June 1956): Same as the #02 with arrestor hook and folding wingtips. Fuel capacity increased further from 1,800L to 2,400L (2x 300L tanks in the wings).

(Note: all drawings at the same scale for easy comparison: 200px = 1m)

 

[Archibald]

Funnily enough less than a decade later the "Mystere XX" moniker was recycled by Dassault for its first bizjet.
I've heard it was because the wings were close from the ones of the Mystere IV.

Just like Learjet borrowed its wings (indirecltly at least) from FFA P-16.

 

[H_K]

And now here are the side-by-side characteristics for the 3 Mystere Xxii designs, showing the incremental optimizations over time to improve range & performance.

1. Mystere XXII 01 Prototype (May 1955, updated May 1957)

2. Mystere XXII Marine early concept (June 1955): Note the increased fuel (from 1,600L to 2,400L) and R105 engines (which are slightly heavier and more powerful than Gabizos: +100kg engine weight). Climb rate at 10,000m altitude doubles from 11m/s to 22m/s. Navalisation penalty is approx. 230kg + 75kg additional equipment.

3. Mystere XXII 02 (Jun 1956): Note the afterburning Gabizos. This increases engine weight by 210kg (from 580kg to 790kg). Structural weight also increases by ~400kg (not sure why by so much). On the positive side, note the greatly increased climb rate at both sea level (from 44m/s to 80 m/s) and at 10,000m altitude (from 11m/s to 40m/s). Speed at altitude is also now slightly supersonic (from M=0.97 to M=1.07).

 

[Archibald]

This supposed Gabizos would work. They did not. At all (funny how Gabizo sounds like Les shaddocks language GA-BU-ZO-ME !)

 

[Petrus]

And now here are the side-by-side characteristics for the 3 Mystere XX designs, showing the incremental optimizations over time to improve range & performance

Do you have info on range/radius/endurance of those projects?