Atlas FCA-1 Carver fighter project

[Thorn]

I think we are talking official.
The fibreglass display model of the twin engined model is an official model, but as stated, is really giving an idea of what the twin engined model looked like, as opposed to a developed wind tunnel model.

That drawing above is a non-official extrapolation of the fact that when the project moved from a single engined model to a twin, various configurations were looked at.
These looked-at configurations included single and twin vertical stabilisers.

From the shape and overall layout, the twin-engined variant was in the Mirage 4000 size category, whilst the single engine was in the Mirage 2000 size category..but perhaps marginally bigger due to the requirement for greater range needed by South Africa considering the much larger theatre they were operating in.

In any event, the displayed model of the twin engined variant is only one of the models.
It has been stated by some who have seen them, that there were definitely single and twin vertical stabiliser models.

It is a beautiful looking design either way.

Edit: Thorn..could you not perhaps tap into some of your previous contacts from your previous work in another life and find out more?

Hi kaiserbill

Regarding the edit. I think that I have a good idea, but check out my conversation with you just to make sure... .

 

[Thorn]

The SMR project kicked off in 1989 but I would guess high level discussions opening up the possibility thereof must have been going from 1988 already. Actual technical work only started in 1990 with the SA team going to Russia. They operated as Aerosud as pseudo independant from Atlas. Carver was cancelled in 1990/91 odd to the best of what I can asertain.

Other than an Atar powered single engine design no other engine/airframe combo to the best available information proceeded very far at all.

Thanks for the timeline. Saved me some online browsing and local database diving.

 

[Thorn]

About the size of the twin engine model:

An engineer on the project explained to me that the engine size and weight offers clues as to the eventual size.
This is common sense, and I knew that there was a rough "rule-of-thumb" regarding this before our conversation.

It therefore stands to reason that if the upgraded indigenous ATAR 9k50 was to be used, an aircraft in the same weight and size class as the Mirage 4000 would be the result.
Ditto for a Spey powered example.
If the Aerosud engine was used, some minor gains in making it smaller and lighter could be achieved...probably approximating around a ton in weight.
If the mooted under-the-counter purchase of the M88 had come about, then an aircraft perhaps only marginally heavier and larger than the Rafale.

A completely indigenous engine would only result in complete speculation.

The upgraded ATAR 9k50 had, amongst others, as two of its major goals:
1: A thrust increase.
2: weight reduction.

The thrust increase was apparently achieved (10%).
The weight reduction did not achieve as much as was aimed at before cancellation.

Not much by way of M88 I could find regarding this powerplant & SA, but found this at https://hushkit.net/2019/06/25/10-exotic-cancelled-fighters-from-countries-you-didnt-expect/

"The nation did not have the know-how to build its own jet engines and instead unsuccessfully attempted to acquire French M53s and designs for the M88 by subterfuge, and it was stuck with the elderly Snecma Atar".

 

[MadRat]

If you are looking at Spey, then why not RB.199?

I thought the British cut them off from major programs in that timeframe.

 

[BLACK_MAMBA]

If you are looking at Spey, then why not RB.199?

I thought the British cut them off from major programs in that timeframe.

This is not just a matter of going to the market and picking the engine you want thanks to the sanctions. SA could not even get their hands on J79's from Israel thanks to the strong US link. Obtaining engines needed a seller willing to look the other way and a middleman to hide behind. That is mostly how extra Atar's were obtained.

The Spey was in use on the Buccaneer so there was local familiarity in servicing it although the 101 and 202/3 still have plenty differences. The Spey 202/3 was only used on UK aircraft so no international partners involved unlike with RB199 and it being an older technology engine by this time period maybe under less scrutiny. It must be noted that everything that emerged thus far still points to the Atar as choice engine - simply because of availability I imagine. RR's support was mainly on spares level from 1985 onwards. As I said previously, obtaining enough engines to fit to a fighter fleet with spares is different than getting one or two as is the case with Spey 202/3.

Edit: Kaiserbill brings up some interesting links to exporting the reheat Spey... I still mark it as an outside chance, but certainly not impossible.

 

[Bladerunner]

The three most likely candidates for a powerplant would probably be the reheated Spey, SMR-95 and the ATAR 09k50. I drew all three engines to scale for my twin tail fin illustration to compare their size in the fuselage, and the Spey is quite girthy...lol

 

[zen]

The positives on the Spey extend to greater flexibility in a future engine replacement.

One can also see post Apartheid RR trying to flog 205 as an upgrade.

It would also put the twin engined Carver into F4 or F15 scale. No mean achievement if they had done it.

 

[kaiserbill]

Black Mamba, did you manage to find the pics of the Speys at Swartkop?

I find it particularly interesting the point that, as you said, Atlas re-established good relations with Rolls Royce from 1985 onwards, allowing spares for the Buccaneer Spey engines.
This was at the height of sanctions, although I know plenty of under-the- counter dealing went on.
And it's also a crucial time period of the Carver program.

The head of RR at Atlas that mentioned the Spey in relation to the Carver... I assume this was the South African liaison dealing with RR?

It's an intriguing situation.
Not just for perhaps wholly imported engines, but rather for engines built up from imported components with perhaps locally manufactured add-ons.
With a different afterburner section, or exhaust nozzle for example, it could be presented and carried off as a local development of the Spey. There is precedent for this type of subterfuge.
The local turbine industry certainly was moving in the direction of local production and development of turbine blades (including single crystal), hot sections, design, gearboxes etc.

A South African company for example ended up manufacturing gearboxes for RR turbofans in the early/mid 1990's, shortly after sanctions ended.
Clearly, to move with that rapidity, they were utilising work and infrastructure done previously.

 

[BLACK_MAMBA]

It is somewhat hidden in between other engines, but I attach a admittedly poor pic of the reheat section - I have not been able to get to the scrapyard to get better pictures. I also attach some pics of the Spey forward section (exactly the same as the other forward section in the scrapyard beside the reheat section) on public display incorrectly marked as a Spey 101 (they also have a SMR-95 marked as a RD-33...). Notice how even the external plumbing is a match for the attached Phantom Spey.

The head of RR at Atlas that mentioned the Spey in relation to the Carver... I assume this was the South African liaison dealing with RR?

He was in charge of all RR service work at Atlas. I assume some level of direct comunication with RR was involved?

It's an intriguing situation.
Not just for perhaps wholly imported engines, but rather for engines built up from imported components with perhaps locally manufactured add-ons.
With a different afterburner section, or exhaust nozzle for example, it could be presented and carried off as a local development of the Spey. There is precedent for this type of subterfuge.
The local turbine industry certainly was moving in the direction of local production and development of turbine blades (including single crystal), hot sections, design, gearboxes etc.

Atlas did initially pass off the Turbomeca Makila used in the Oryx and Rooivalk as the Atlas Topaz so even a straight rebrand is not off the table...

 

[kaiserbill]

Very very interesting. Thanks.
Would be interesting to discover the date these were acquired, and their providence.

 

[Bladerunner]

The Spey was definitely proposed as a powerplant for the single engine Carver, and would have been a sensible option for the twin engined designs. Had some more fun with illustrations of the single seat twin engined version with the single tail fin (the fiberglass model that was at the Rand Show) with Spey engines, and it looks plausible.

 

[Bladerunner]

Did an illustration of Carver 1 how I think it would have been fitted with the Spey. It's a tight fit at the rear, but it would have performed well.

 

[kaiserbill]

How does the original Spey Mk202/203 exhaust/afterburner nozzle though compare with more modern fully variable exhaust nozzle that came afterwards?
I suspect there was considerable room for improvement there, considering the 20-25 years of passage between the 1960's Spey and the late 1980's.
Does anyone know what work was done in that area for the developed 25 000lbs Spey Mk205 that was kicking around in the same timeframe as Carver in the mid/late 1980's?

 

[BLACK_MAMBA]

Re the Cheetah & F1 - the engine was the same with both airframes from talking to the engineer, but the cold feathers where different (obviously). They however were part of the airframe and not the engine - they connected the the SMR's hot flaps so the engine inside wasn't required to be different, but the tailfeather cone was to match the airframe.

This post of mine from a while ago recently came up again. In the meantime it was confirmed that there was an SMR-95A and B for the Mirage F1 and Cheetah. The difference however was not in the actual engine but in the gearbox accesories. The Cheetah/Mirage III had less airframe space below the engine compared to the F1 so required a different gearbox configuration. Klimov saw and sold the gearbox and engine as a combo, and since the gearboxes differed from there the variants -A and -B.

As to Carver II, I would reason the lower profile Cheetah gearbox would be the prefered choice but that is pure speculation on my part. From that post I still maintain that had the SMR ended up in Carver, it would have been no different from the one used in the other types to retain commonality.

 

[Scott Kenny]

This post of mine from a while ago recently came up again. In the meantime it was confirmed that there was an SMR-95A and B for the Mirage F1 and Cheetah. The difference however was not in the actual engine but in the gearbox accesories. The Cheetah/Mirage III had less airframe space below the engine compared to the F1 so required a different gearbox configuration. Klimov saw and sold the gearbox and engine as a combo, and since the gearboxes differed from there the variants -A and -B.

As to Carver II, I would reason the lower profile Cheetah gearbox would be the prefered choice but that is pure speculation on my part. From that post I still maintain that had the SMR ended up in Carver, it would have been no different from the one used in the other types to retain commonality.

Makes sense. The main difference between the various CFM-56 engines early on was where the accessory drives were. The KC-135R and Airbus engines were at the bottom of the engine, IIRC, while the 737 engines were on the sides. KC0135R engines were otherwise the same as on the 737s, same fan diameter etc.

 

[BLACK_MAMBA]

In clarity to my pervious post - I believe it was more to do with the location of the main gear and their retraction wells, than anything else. The Cheetah D (Mirage IIIDZ, D2Z and Nesher T based all with Atar 09C) was relatively easily upgraded to the same engine as the Mirage F1 namely the Atar 09k50. I do not believe the engine change required gearbox changes, but rather engine control connection changes etc. Both shared the same mounting points. From the attached pictures I think it is clear why I think the Cheetah gearbox would have received the nod for Carver II. Development had already switched to a twin when the SMR project became a reality thus my exclusion of it for consideration in the single engine design.

Cheetah gearbox:



Mirage F1 gearbox: