This whole thing started with the government sniping at its own people!

They keep them in the city and then they and the Russians can say “oh well, we tried. You can’t say we didn’t try…” They will then increase the bombardment under the pretext that they gave anyone truly innocent the chance to escape.

This is a pretty absurd post, with all due respect Mrmalaya.

The BBC Effect…

You get the feeling Goldust and Byoin are familiar with each other….

What does that tell us about the original engine fitted to the Mirage?

It tells us various things actually, mostly that customers wanted options, a lot of it for political or industrial reasons.

The Avon powered Mirage was looked at by Australia, as they had used an earlier version of that engine to e=re-engine their licence built CAC Sabres, and there was some political influence apparently to get a British component on board. Remember this was really the first time Australia had moved away from a British fighter (apart from perhaps WW2 and all the expediency that entailed) and was incidentally the first fighter used, and licence built in Australia that had been designed in the metric system.

The Australians were interested in the more powerful ATAR 09K, but by the time a decision needed to be made, it hadn’t yet been fitted to a Mirage III airframe, and thus the lower risk and lower powered 09C was selected.

” Thus by early May it was apparent that the expected advantages in takeoff performance, rate of climb, and range for the Mirage III with the Avon Mk67 were not a significant improvement over the Mirage IIIE, whereas overall performance above 40 000ft was somewhat inferior, although the Avon version was able to achieve higher speeds without afterburner at altitudes below 45 000ft. On the other hand, the development potential of the Avon Mk67 engine was limited to the fitment of a larger tailpipe (36″ diameter as opposed to 28.8″ in the standard engine) and the expected benefits to thrust and fuel consumption were not comparable with those available from the ATAR 9K.
The ATAR engine offered important additional benefits, being lighter and cheaper than the Avon and was perceived to have benefits due to ease of manufacturing and servicing together with simplicity of operation…”

Incidentally, 160 ATAR 09C’s were licence produced in Australia in the end, with a final local content of 85%.
Here is an excellent reference book, detailing much of the above, of the Mirage story in Australia:
http://www.radschool.org.au/Books/the_raaf_mirage_story_opt.pdf

The primary driver for the selection of the J-79 in Israel was military credits/aid from the US, as well as the existing use of that engine by the hundreds in Israeli service, and has been discussed above.

By the time South Africa was re-engining the Cheetah (and Mirage F-1), the Mirage III had been in service around the globe for about 30 years.
In the meantime, the rise of the turbofan had occured, with no new fighter designs then being looked at featuring turbojets.
It is also worthwhile recalling that South Africa was casting an eye around for a modern turbofan to power the Carver, and the re-engining of the Cheetah and Mirage F-1 must be looked at in that light.
It is also worthwhile remembering that whilst looking around and fitting a turbofan to the Cheetah, Mirage F-1, and considering it for the Carver, the ATAR Plus programme was on the go, where certain elements of the ATAR 09K50 were being redesigned (with new compressor, new turbine, and new electronics) to achieve a thrust increase of 10% plus.

The M4k had a very high thrust available, as the Typhoon or Rafale have today (actually, they are a league above, but it is normal as they are another generation)

I’m not so sure of this last part.

Merci Guillaume, Please please, give us a hint of what was there 🙂 extra fuel … ?

It is a hybrid, partly a Kfir airframe design, with the fuselage starting to widen at that junction that was built to house the J-79.
All the original SAAF Mirage airframes were utilised to build the original Cheetah E, R reconnaissance models, and D two seaters.
There weren’t enough left over for the Cheetah C programme.
The Cheetah C utilises portions of the Kfir airframe, but in a slender new build rear fuselage that doesn’t need to somehow accomodate the bulkier, heavier J-79 and its associated cooling requirements.
The front fuselage portions are also new. It’s a very interesting hybrid. The differences between the air-to-air refuelling probes and their position also show there are differences beneath the skin of the Cheetah C and Kfir C10, apart from the obvious differences in the front fuselage/nose, and rear fuselage.

Hence my inference to the “big cats”. I was referring to the Pantera which was equipped with the ATAR 09K50 too. The rear fuselages of the Cheetah C and Pantera are different even with the same engine, which are different yet again from the Kfir. The Cheetah C fuselage in the cockpit area is also deeper than the Pantera.
The J-79 installation was an Israeli expedient, based primarily on supply, military credits, and existing maintenance facilities and supply lines due to them already using hundreds of airframes with the J-79. The Israelis never used the most powerful of the ATAR’s, the 09K50, so I suppose that made sense to them.
I’ll reiterate the point that due to the engine and its associated structural/cooling requirements, the Kfir must weigh more than any ATAR powered model, even the heavier, more powerful ATAR 09K50 editions.

The entire Mirage III development family is very interesting, with airframes turning out quite different as they developed. Even the wing planform changed, and it would have been even more had one of the Advanced Combat Wing designs (there were I think 3 different versions) on the Cheetah been fitted to service aircraft instead of only test aircraft. Again, that was a budget/Cold War ending issue that stopped that.
It is testimony to the wonderful adaptive original design by Dassault. As can be seen, the end of the line of the Mirage III family are very different beasts to the original. Dassault got the basics very right.

hello mein kaiser,

could you tell me more about the cheetah vs kfir’s difference in terms of structure?
it seems that you are implying that the cheetah airframe is better suited for all the modern upgrades (canards, radar, etc)

Hello, my sizzling delicious friend.

I’m not saying that at all.
Lion cubs and cheetahs aren’t the only big cats…you get others, such as a panther for example. All cats, yet all different…;)
For example, have a look at my picture on the last page of the Cheetah C, the one taken from the three-quarter view.
Look at the midway point of the dorsal fuselage, near the low profile airscoops.
You will see something interesting regarding the fuselage structure that hints at something.;)

I’m saying that the slightly more powerful J-79 as fitted to the Kfir was not a better aerodynamic match compared to the ATAR 09K50 in the airframe we are discussing…

On the subject of weight:

It is interesting to view the cockpit position of the Mirage III and developments through time.
The original Mirage IIIC fighter had the rear of the cockpit that started slightly behind the air intakes.
As is well known, the multirole Mirage IIIE had a fuselage extension (about 300mm), bringing the rear of the cockpit in line with the air intakes.
The Cheetah C has a further fuselage extension, with the rear of the cockpit now well forward of the air intakes.

The Mirage IIICZ has an official empty weight of around 6400kg.
The Mirage IIIE had an official empty weight of 7050kg.
The Cheetah C is largely redesigned, with a maximum takeoff weight a full 3 tons heavier than the Mirage IIIE.
It has slightly a slightly enlarged wing area courtesy of the dogtooth extensions instead of the traditional slot.
It has a different, beefed up undercarriage.
It has canards.
It is longer, and has an air-to-air refuelling probe.
It has a heavier, more powerful engine.
It has an internal jamming suite, multimode radar and electronics.
Different control motors for its flight system.
Cockpit canopy…
The list goes on….
Take a look at the pics of the two aircraft below: A Mirage IIICZ and a Cheetah C. They’re almost two different aircraft, sharing the same layout.
The 6600kg empty weight given on wiki for the Cheetah C is fiction, as is the original Kfir empty weight (canards, heavier engine, cooling/heat shield requirements etc) when compared to the Mirage 5 it is based on…
And the developed multirole Kfir C10 will be that much heavier yet again.