avatar_Hobbes

TSR.2 mentioned on Strategypage

Started by Hobbes, December 10, 2004, 02:30:48 AM

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Hobbes

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So, is Hutchison right, or would these problems have been solved eventually?  

overscan

According to my information the TF30 has better fuel consumption in dry thrust than the Olympus but worse in afterburner, which would be expected from the fact that one is a reasonably high bypass turbofan and the other a turbojet. The TSR2 would therefore likely have had less range in an economic medium altitude cruise than F-111. On the flipside, it would have been a better performer in supersonic flight.  
Paul Martell-Mead / Overscan
"What if?" addict

retro_seventies

exactly - there is no doubt that a more efficient, fully developed engine would have been used in production aircraft.
"Computer games don't affect kids. I mean, if Pac-Man affected us as kids, we'd all be running around in darkened rooms, munching magic pills and listening to repetitive electronic music." Kristin Wilson, Nintendo Inc, 1989.

overscan

#3
well- yes, but it would never be as fuel efficient as a turbofan in economic subsonic cruise without turning it into a turbofan. The Olympus was a good engine for Concorde because it was designed to fly at Mach 2.0, a regime where a turbojet is more efficient than a turbofan.

The Russians found this out to their cost with the Tu-144, which used off-the-shelf turbofans and could only cruise at Mach 2+ by using partial afterburner which crippled efficiency. They had to put a pure turbojet in for the Tu-144D, which was a fine machine but had no real purpose and was quietly shelved.
Paul Martell-Mead / Overscan
"What if?" addict

retro_seventies

absolutely Paul - i agree with you 100%...but do you not agree that chances are that in later production TSR2s and almost certainly in MLU's that a powerful yet efficient turbofan would have been introduced?

Would the "traditional" Hi-Lo-Hi mission profile have suited the TSR2s turbojets? Possibly yes, possibly no, but provided that tanker support was available, i believe that she would have been able to get the job done...

Not that i'm saying that the F-111 wouldn't have been a good buy for us - heresy possibly, but it would have been a useful addition to our arsenal, and would have filled a glaring deficiency in our offensive capabilities.  
"Computer games don't affect kids. I mean, if Pac-Man affected us as kids, we'd all be running around in darkened rooms, munching magic pills and listening to repetitive electronic music." Kristin Wilson, Nintendo Inc, 1989.

retro_seventies

very true lee - a pox on the government always.
"Computer games don't affect kids. I mean, if Pac-Man affected us as kids, we'd all be running around in darkened rooms, munching magic pills and listening to repetitive electronic music." Kristin Wilson, Nintendo Inc, 1989.

elmayerle

Quoteexactly - there is no doubt that a more efficient, fully developed engine would have been used in production aircraft.
I've been speculating for some time on an afterburning Medway for the TSR.2 and I've got a couple "Spey" nozzles from an early Revell Phantom for such a purpose.  Truthfully, though, I'd prefer to see the engine be used by the Swedes in the Viggen isntead of the JT8D and the afterburner from that adopted rather than RR developing one.  If you look at what Volvo Flygmotor aan RR did with Avon afterburners, Volvo seems to do the better job.  Failing that, perhaps a joint development effort with SNECMA for advanced Mirage variants would do, especially since SNECMA managed to get better, or at least more stable, performance from the JFT10/TF30 engine than P&W did.
"Reality is the leading cause of stress amongst those in touch with it."
--Jane Wagner and Lily Tomlin

elmayerle

#7
Lee, the intention was to do some reworking of the aft end of a TSR.2 to work with them.  I will admit, I've always wondered why the TSR.2's Olympus was 100 in. longer than an Iroquois of equivalent performance.  Was it all in the afterburner?

I rather suspect the TSR.2 would've hit teething troubles like any new and advanced program, though not the same ones as beset the F-111.  You really have to have done your wind tunnel data reduction wrong to choose what was shown, by later testing and flight testing, to be the highest drag aft-end configuration possible.
"Reality is the leading cause of stress amongst those in touch with it."
--Jane Wagner and Lily Tomlin

overscan

Having looked into it a little, it seems that the TSR2 was heavily optimised for supersonic cruise. The prototype went supersonic on dry thrust only, and it was expected to fly at Mach 2 for long periods of time. This explains both the huge thrust of the engines relative to the weight of the machine and the very large fuel load.

I've got a nice cutaway of the Concorde's Olympus variant which doesn't seem to have an excessively long afterburner section, but then again SNECMA were in charge of the back end of that version!
Paul Martell-Mead / Overscan
"What if?" addict

Zen

1 prefered engine by the UK industry was mainly the 'Medway' the Speys big daddy.
But forced mergers was the name of the game by the government so Bristols Olympus was prefered by the government.
Medway never made it to production, but its little child the spey did.
The alternative preference was for the Conway, again ruled out due it being a RR product. Shame Napier never made their turbofans as they had a very modern bypass ratio and would have been much more fuel efficent than any of the other options.

Another irony is Bristols very own Bs.100 very much in the right performance margines for the TSR.2 especialy with its 'short lift rating' giving it that extra fast increase in thrust for 'escape' and take off. A straight through variant with a big afterburner would have been just the thing and helped it with the P1154 too. IMO a UK Viggen with it would have been a wonderful thing to have seen!

2 the Olympus used for concord was practicaly pulled apart, redesigned and rebuilt to scale up and beef up the core for sustained supersonic flight. This was not exaclty compatible with the Ol.22. The enigne was bigger than the Ol.22 and more expensive too. Where it shared things with the Ol.22 was in technology and basic design along with some 'heritage' from realier Olympuses.

F111 was slower at max speed, slower to accelerate, and I bet had a lower ceiling.

Further the TF30 troubled engine it was and poorly fed by the F111 inlet was not exaclty a supercruise engine like most turbofans of the periode.
Mass flow is what counts there.

3 do note that the Olympus like most of the engines opted for the OR339 machines made them rather overpowerd for the priode and the requirement of cruising at transonic speed at low level. What drove the excess power was the need for a quick take off and the ability to quickly accelerate out of trouble if need be.
The F111's TF30's where more resonalbe in terms of thrust to the weight of the aircraft as is the RB.199 to the Tornado.
To win without fighting, that is the mastry of war.

Zen

Note for the hard of reading and thinking, 'straight though' means no 'four poster' nozzels but the exhaust ejecting straight out the back like most jet engines. Yeah gods I hate having to add that but every time I mention this people manage to completely miss the meaning of it.
To win without fighting, that is the mastry of war.

P1127

#11
But then the design of the TSR2 was Tactical Strike - in UK parlance drop a sub-megaton nuke. Strike meant nuclear weapons, so the max range with a 2000lb store (WE177) would be optimised. It was designed to get there very quickly at low level.

Not designed as a 10,000lb interdictor, hence why the bomb load increase dropped the range.
It's not an effing  jump jet.