Alternative history powerplants

zen

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What happens if....

Bristol builds the BE.30 or 33?
Or AS the P.151?
Or RR one of the RB.106 versions?
Maybe the small RB.126 or the large RB.128

What happens if the Buccaneer flies with the BE.33 instead of the Gyron Junior?
No Spey for the mk2 I might suggest.

What happens if India buys the BE.30 for the Marut?

Might the Gnat mkV get further with one of these?

Might the Lightning be so fitted?

What happens if the F4 is still chosen but instead of the Spey it gets the Thames?
Higher velocity exhaust means a much higher and faster flying F4.

Could we see F104 or F8 with one of these?
Had the bigger Thames versions been built, would this be chosen by Avro Canada for the Arrow?
Without the costs of getting Orenda to develop the Irequois?

Would we see these developed into maritime GT's?
Ships powered by RB.128 instead of Olympus?
Or Tynes replaced by BE.30?

How would it effect the process of Concord? Would it fly with RB.128s?

How might turbofans develop if these new cores exist?
A bypass BE.30 or RB.106 for example.

Let's add a real wildcard in. What happens if a test article is built using EE's ramjet wing?
Could we see a missile development?
 
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sferrin

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"Could we see F104 or F8 with one of these? "

The F-8 actually ended up with the more powerful J75 in the form of the XF8U-3.

"Higher velocity exhaust means a much higher and faster flying F4. "

Not necessarily. The F100-PW-229 has a much higher exhaust velocity than the F110-GE-129 but apparently the latter smokes the former performance wise at all altitudes & speeds. (No idea why.)
 

Archibald

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I love the Marut, cute little pointy jet fighter that never got a viable powerplant in the first place.

J79 and Avon are basically same diameter / size / length / weight. And much smaller than the J57which was bulky - an older generation.

A case could be make that, the J57 stuck into the Crusader... rear end was so large and heavy, the resulting large engine bay & fuselage diameter could have sheltered
- the Lighting and Draken Avon derivatives that flew in the 60's
- plus the improved variants that were cancelled in the mid-50's - RB.106 / 122 /128.

The Crusader III traded a J57 for a J75 but it was essentially a brand new aircraft, the Crusader name was a ploy from Vought to reassure / fool the USN by telling them "oh yes, of course, it a Crusader derivative".
The real loss as far as Crusader derivatives go, was the V-1000 from the late 60's. Considering how the F-104, Skylancer and Super Tiger ruled the skies after trading their XF-104 - Tiger > J65s and Skyray > J57 for the J79, the Crusader would have been boosted by such swap, too.
And then once again, where a J79 fits, an Avon fits, too. Hmmm RB.146 powered Crusader... an Avon powered Phantom, now that's an idea that make so much sense, it is not surprising it was NEVER considered.

Swapping Avons for J79s in a Phantom airframe might be easier than the OTL Spey monstrosity. As far as thrust goes, late Avon and J79 were 7800 kgp when poor Atar 9K50 was barely 7200 kgp. It is no surprise Tonton Marcel hated SNECMA and proposed a boatload of Avon and J79 powered Mirages.

Note that in 1963 Australia was proposed an Atar-Phantom (Model 98DX according to Joe Baugher) for the sake of commonality with their Mirage III-O. some years before in 1960-61 and in a reverse move, Dassault actually flew an Avon-Mirage !
Funnily enough, had the Avon-Mirage been picked by the RAAF, then the Phantom proposal would have to eat Avons, too, ot Atars.
I kind of like these hybrids airframe-engines that never were.
 
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zen

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In context of a comparison between turbojets and turbofans, the fan air is slower and cooler, which means that while it's thrust is potentially equal to a turbojet, the lower velocity /temperature results in less effective power at higher altitudes and speeds.
Thus while the Spey was more efficient at low altitude and consequently lower speeds it's performance at altitude suffered as it did at high speed.
See for instance the debacle of the Spey offering to the P1154.

Hence if instead of the Spey the UK fitted the F4 with the Thames, due to the higher temperature and velocity of the exhaust, performance would be superior. Not just to the Spey, but compared to the J79.
Result would be an F4 which can take off with dry thrust at low weights from Ark Royal, higher rates of climb (due to the lower fall off of power at higher altitudes) and potentially higher speeds.
Though on this last point, the F4 was limited to mach 1.9 in non-all-out-war due to the thermal limitations of the cockpit canopy transparencies. Mach 2+ speed meant replacing the transparencies.
However the higher performance, would be felt in accelerations at all altitudes.

While the Thames was predicted to have better s.f.c figures than the Avon. It's reasonable to presume it's not much worse than the Spey which wasn't that much better than a turbojet due to it's low bypass ratio.

The only real world comparable engine to the Thames, is the Orenda Irequois.
 

zen

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I agree that it would have been simpler to opt for a licensed Avon Crusader, with say three 30mm ADEN cannon, AI.23 and Firestreak.
This could then be upgraded with Thames, improved AI.23 and Red Top.
And in turn rather than replace, just upgrade further the AI set and missiles.
 

Archibald

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I don't know how large were the Red Top and Firestreak but the French Crusaders could carry R530 on the sidewinders fuselage pylons.
f8p-01.jpg
 

pathology_doc

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Red Top is not that much smaller than Sparrow, in terms of body diameter and overall wingspan, though it is much lighter - 330lb as opposed to 450-500 (depending on variant). The difference is that Red Top's major fins are not the control surfaces; those are at the tail, and are much smaller. Sparrow's fins are of roughly identical size fore and aft, and the actuator surfaces are the FORWARD wings.
 

apparition13

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The real killer engine here is the RB.106, and I think the biggest powerplant mistake (with the Orenda Iroquois second) since it was being designed as a drop in replacement for the Avon. That should put it at about a length of 126 in (3,200 mm), a diameter of 35.7 in (907 mm) and a weight of 2,890 lb (1,310 kg)*, but with significantly more thrust at 15,000 lbs dry and 20,750 wet.

For comparison, the J79 is longer and wider, and 1000 pounds or so heavier, the J57 is also longer and wider, but 500 or so pounds lighter, with the J52 is a little shorter, slightly wider, and also around 500 pounds lighter, and the Atar much longer, a little wider, and around 300 pounds heavier.

It has 3000 lbs of dry thrust on the US engines and 5500 or so on the Atar, and about the same 3000 lb advantage in afterburner thrust on the J79 and J57, while it has 7500 on the Atar.

Most of the Avon birds are out of production, but as a retrofit would improve all of their performances (imagine a CAC Sabre with 15k thrust), and the J35 at least is still being built.

Both the A-4 and A-6 (J52) would benefit at takeoff and for egress and defensive maneuvering. With the AB the A-4 would be above unity at it's combat weight, and an already pretty good dogfighter might become a great one.

But the killer gains would be for the J79 and Atar aircraft. Between the weight reduction and thrust increases the F-4, F-104, F11-1F Supertiger (the timing is right for an export version using the RB.106), and Mirage III would all be right at or just above a 1-1 thrust to weight ratio.

The Supertiger would now be a much more attractive fighter, especially for carrier ops, and may be attractive to the UK and France in that role, and perhaps for the US Navy as a small carrier replacement for the F-8. A CL1200 like F104 would still be around 1-1. Although I think both scenarios are somewhat unlikely

The already capable Mirage III would be a Boyd and Sprey dream come true, and would demonstrate that in '67.

But the biggest effect would be with the F-4, since that much extra power would make it a much better dogfighter, and I think would have a good possibility of keeping the F-X program that led to the F-15 to it's earlier incarnation of a 60k pounds and variable sweep strike-fighter, the Republic FX-6 being a an example, given the F-4 would be a more capable air superiority fighter.

If the fighter mafia complained, Mirage III or afterburning A-4s should placate them.


* figures from wiki, so grain of salt, especially regarding diameters.
 

zen

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I think the Avon was 37" diameter, but otherwise yes.
The reheat section is very close to those of the Spey. Likely RR just ported over the work on such reheat units.
The RB.106 ought to be lighter than the Avon due to much higher use of titanium. So the closest real figures would come from scaling the Irequois down a bit.
 

zen

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So had any or all of the trio of RB.123, P.151 or BE.30 gone ahead from '54, they would exert an enormous influence on decisions and designs.
In essence they would figure not just in the NA.39 winner B.103 that became the Buccaneer, but would be the chosen powerplants of the Bristol T.188 research machine, the P.177 or Avro 720 mixed powerplant fighter and at least AWA's and DH's submissions to F.155.
As the P.151 alreawdy figured in the Avro 726, we can also see them likely used instead of Gyron juniors in the 729.

In multiples they would likely crop up in the supersonic recce/bomber studies.

Such engines certain would be explored both for retrofit to the likes of the Hunter, Sea Vixen, Scimitar and Canberra as they would figure in variants of new designs.
As I've said elsewhere, had Hawkers used a pair of these on a P1103 study, this would rightly fall into ideal carrier fighter territory.
These would certainly fit into the Lightning, and rather like the later RB.153 so studied, offset the lower thrust with lower weight and easier installation/access for maintenance, to no appreciable drop in performance.

Had HAL used such in the Marut it would certainly drive the machine to the desired speeds and as a consequence encourage India to fund it's further development.

These would also be a prime option for the later supersonic trainer.

They also fit into the size to power category used for Vickers OR.346 studies, such as the Type 581 group.
 

steelpillow

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What happens if the F4 is still chosen but instead of the Spey it gets the Thames?

Well the Speys hanging out the back caused it a real problem with the sound barrier. The engine change would obviously bring with it a Thames Ba... >mfff!< [gurgle!] ... "come along quietly now, Sir"....:D
 

Grey Havoc

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If Rolls-Royce had been allowed to proceed with their 1964 turbo-ramjet proposal, it could have opened up even more possibilities, especially in the areas of strategic reconnaissance & sub-strategic strike.
 

pathology_doc

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Let's take this thread in another direction - what would have happened if RR had actually made the Vulture work, and Napier had not struggled so much with the Sabre?

Should RR have forgotten about ever starting the Vulture and just gone with the R engine/Griffon from the start? IIRC the Peregrine was never the finest aero engine in history; bolting two of them together (which is what I understand the Vulture to be) could only ever have been a disaster in the making.
 

Nick Sumner

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Let's take this thread in another direction - what would have happened if RR had actually made the Vulture work, and Napier had not struggled so much with the Sabre?

Should RR have forgotten about ever starting the Vulture and just gone with the R engine/Griffon from the start? IIRC the Peregrine was never the finest aero engine in history; bolting two of them together (which is what I understand the Vulture to be) could only ever have been a disaster in the making.

IMHO, the Vulture, or developments thereof could have been very fine engines. The Vulture used Peregrine cylinders, yes, but the spacing on the crank was the same as Merlin, suggesting Merlin cylinders could have been used in later versions. This would give a displacement jump from 42 to 54L . RR characteristically pushed development with incremental changes such as raising boost and RPM which took Merlin from being a 900hp engine (Merlin C) to a 2400 + hp engine (RM17SM development stage). Also, the fix for Vulture (a balance tube to ensure even lubrication IIRC) wasn't even that tricky, they just perfected it after official interest in the vulture had ceased and they'd bolted the supercharger on the back of a Merlin anyway.
 

zen

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Actually another thought keeps hitting me, the UK put increasing funding behind the Avon series engines. Yet the US stuck with a licensed Sapphire, and seem to spiral off away from AS's designs and not to much improvement.

Why didn't the US look at licensed Avons?
 

Hood

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Maybe Rolls-Royce didn't want to sell licences to potential US competitors (having been burned by Comrade Klimov)?
Please correct me if I'm wrong, but RR didn't really begin to sell jet licenses until the Spey series?
 

EwenS

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Let's take this thread in another direction - what would have happened if RR had actually made the Vulture work, and Napier had not struggled so much with the Sabre?

Should RR have forgotten about ever starting the Vulture and just gone with the R engine/Griffon from the start? IIRC the Peregrine was never the finest aero engine in history; bolting two of them together (which is what I understand the Vulture to be) could only ever have been a disaster in the making.
If the Vulture is made to work, then no Lancaster, and so no Dambusters, no Tallboy or Grand Slam unless in a later generation aircraft. Maybe even no Halifax depending how soon the problems get ironed out.
 

steelpillow

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My alternative history diverges during the mid-thirties. The likes of Harry Ricardo and Ernest Hives foresaw a steady increase in compression ratios as petroleum fuels increased in octane rating. Such fuels must avoid volatile components, to prevent pre-ignition. They thus approach the specifications for Diesel oils. Moreover, as compression ratios increase so the stresses on the engine increase and its weight grows accordingly. The high weight of Diesel engines has always been their undoing, but that disadvantage was counterbalanced by the greater energy content of Diesel oils, so needing to carry less fuel volume, and would be further eroded away over time. The higher combustion temperatures would benefit both kinds of engine, making the increased weight worth while.

Direct injection is intrinsically superior to the carburettor, avoids pre-ignition and is also an essential feature of oil engines. Germany turned to the injection route exclusively and the Junkers Jumo Diesel became one of the early mainstays of the wartime Luftwaffe. Supercharging and eventually turbocharging were also pencilled in for the future and would appear during the coming war. They too drove compression ratios and combustion temperatures upwards.

Then there is the two-stroke cycle, which in theory has twice the power-to-weight of the four-stroke. High valve overlap (inlet and exhaust valves open at the same time) greatly improves the scavenging of exhaust products and had long been essential in any high-performance two-stroke, but the imprecise fuel timing of the caburettor was holding it back and direct fuel injection would be key to its further exploitation.

In the early 1930s Harry Ricardo began research on a two-stroke Diesel aero engine featuring such advanced ideas as stratified charge and sleeve valves (yes, a two-stroke sleeve valve!). Its potential high power for low weight caught the RAF's eye as a "sprint" engine for interceptor fighters, but they were still stuck in the world of aviation petrol. By the time Rolls-Royce took Ricardo's project forward as the V12 Crecy it had become a petrol engine. However its fundamental flaw eventually proved the particular design's inability to accept a super- or turbo-charger.

The problems which beset Germany in following this path, albeit four-stroke, and led to abandoning further development of the the Junkers Diesel, were all of materials supply and did not hinder the UK.

In my alternative timeline Ricardo faced down the petrol decision, realising that by the time it came to the market, the only fundamental engineering difference between the two fuels would be whether a spark plug was needed, so why make life complicated? The Crecy therefore retained its Diesel fuel, also reducing the need to convert CAV's injection technology and further simplifying the necessary development work. In this timeline Ricardo also had the foresight to design the Crecy in such a way as to make super- and turbo-charging it practicable, a lucky break which would in reality save the day for the Merlin.

By 1941 the basic Crecy prototypes were proving their worth and a two-stage supercharged version was under development. Its fuel injection especially was decisive in giving unparalleled high-altitude performance. The decision was made to abandon the two-stage supercharged high-altitude Merlin and the whole Griffon project, and to focus on getting the Crecy into production. The basic Crecy was manufactured in small numbers from late 1941, with the supercharged version entering volume production in 1942. A low-altitude version finally supplanted both the Merlin and Napier Sabre in 1943, its fuel injection proving the killer feature over the inherently inefficient carburettor (Napier began development of a fuel-injected Sabre but canned it at the end of hostilities). The Bristol radials were relegated to large aircraft which lacked the extreme performance requirements. From then until the advent of the jet, every major British aero engine employed the sleeve valve. The swirl throttle, long pursued by French and Russian, and latterly German designers, finally made it into the Crecy in 1945 but would see war service only in Korea.

(Key references for the real-world background include The Secret Horsepower Race by Calum Douglas and The Rolls-Royce Crecy by Nahum, Foster-Pegg and Birch.)
 
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JohnR

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I've only just read this thread, as it was originated during my computer went boom absence. It is truly fascinating and displays an enviable knowledge of the development of British jet engines.

Could I ask; as usual, for a source of information on the various engine, I did buy Bill Gunston's Encyclopedia but I was rather disappointed in that it just really listed engines largely without any technical details. I'm not looking for anything really technical, just a listing of the basic specification of the engines, dimensions, weights, power rating etc.

Regards.
 

PMN1

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Let's take this thread in another direction - what would have happened if RR had actually made the Vulture work, and Napier had not struggled so much with the Sabre?

Should RR have forgotten about ever starting the Vulture and just gone with the R engine/Griffon from the start? IIRC the Peregrine was never the finest aero engine in history; bolting two of them together (which is what I understand the Vulture to be) could only ever have been a disaster in the making.
If the Vulture is made to work, then no Lancaster, and so no Dambusters, no Tallboy or Grand Slam unless in a later generation aircraft. Maybe even no Halifax depending how soon the problems get ironed out.

Even when it worked two Vultures were not really enough for the Manchester......
 

norseman

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I loved my chats with old Ed, he was early old school engineering and consultancy for Bristol, RR and a few others in materials development and we got to know each other on a specific naval project we worked together. He was scathing on the handling of the RB.106 and it's bigger brothers. He also worked on some material upgrades on the Avon family and says it never reached it's peak capabilities far less what the 106 was offering. The improvements in maintenance, fuel consumption, performance across the entire range (height, temperature, density etc), growth potential (first production run was looking at more like 16-16.5k dry and 23k wet). Imagine this engine at this time period in early phantoms and current hunters and the ongoing into Mirage 3/5/IV, Super Sabre, Canberra etc. The big boy version's were well up into the low 30k+ arena with minimal development. As a J79 & late Atar competitor it would have wiped the floor and considering the development that went into it, it is staggering how much has been swept under the carpet. Britain had a staggeringly good engine here that was well thought out, played on extrapolated technology from the Avon family with a very impressive adaptive improvement program but all swept away due to the Avon being good enough and some fairly hefty external political pressures. Also how far developed it was is also missing from many history books. We know from the Israeli development on the "Super Phantom" that it could handle a lot of extra power, acceleration and stress without breaking. The use of the 106 here also meant minimal intake modification. To have a really optimised epic Phantom there were 2 missed opportunities here (not including the Israeli approach which was also clever and doable), switch out the J79's for 106's in in a minimal change option or stick with the expensive awkward Spey adaption but use the 17-18k dry/27-28k wet version which didn't need a change from the highly adapted inlets of the base Spey but gave a better all round engine with major performance advantages. They were tested (only 25k wet version which was still epic) but it fell back to that "good enough" line. The joys to have unlimited money for defence....... (still, keeps me in a job I suppose).
 

steelpillow

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the RB.106 ... As a J79 & late Atar competitor it would have wiped the floor and considering the development that went into it, it is staggering how much has been swept under the carpet.
...
We know from the Israeli development on the "Super Phantom" that it could handle a lot of extra power, acceleration and stress without breaking. The use of the 106 here also meant minimal intake modification. To have a really optimised epic Phantom there were 2 missed opportunities here (not including the Israeli approach which was also clever and doable), switch out the J79's for 106's in in a minimal change option ...

According to Wikipedia the outlay on the RB.106 was £100,000 - paltry even in those days. The RB.106 was first choice for the Avro Arrow, but their Plan B was the J67, a license-built Olympus. On termination of both engines, DHC's engine arm Orenda developed its own 106-like engine. I don't know how much R-R effort they licensed, but it is a shame they could not do a "let's develop a joint product here and sell it both sides of the pond."

A perfect what-if scenario for the Orenda-Rolls-Royce ORR.106 Iroquois to put Arrows and UK Phantoms at the tip of an international sales success.
 

JohnR

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What was the power rating of the Rolls Royce Thames Jet Engine?
 

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steelpillow

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What was the power rating of the Rolls Royce Thames Jet Engine?

RB.106 - [Project] Twin-spool turbojet 15,000 lbf dry,* 20,750 lbf reheat
- RB.106: Intended as Avon replacement, project cancelled in March 1957
-- https://www.flightglobal.com/pdfarchive/view/1956/1956 - 1246.html
-- Orig. aimed at 10,000 lbf, poss. named 'Thames', for SR.177, EE P.6D

That link is dead - the Flight archive has been taken down. Here is a copy preserved on the wayback Machine: https://web.archive.org/web/2016030...bal.com/pdfarchive/view/1956/1956 - 1246.html

However the reference is very short and makes no mention of the "Thames" name:

"R.B. 106. No official mention has yet been made of any engine with this designation, but references to such a unit have appeared several times in various publications. All such reports referred to it as a high-thrust turbojet and it is described as having a two-spool layout. An American report states that Westinghouse are anxious to manufacture it under licence."
 

Archibald

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The Iroquois was indeed an extremely impressive achievement for Canada. It put them at the level of GB and USA, ahead of USSR which was lagging behind. And far, far ahead of France SNECMA and its Atar dead-end.

J75 / J93 / J58 = Iroquois = Gyron / RB.122 / Olympus / Conway

That were the most powerful / advanced engines in the world, circa 1958.
 

Hood

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The RB.106 Thames could have been a real game changer.

There are a couple of things that cloud the dream though.
What aircraft would it have realistically powered? The cuts of 1957 meant there was little that would have immediately used it from British drawing boards, maybe the Bristol Type 188 and TSR.2. There was nothing else around this time and by 1960 Bristol Siddeley looked to be getting a far better deal with its four-posters (P.1127, HS.1154, 681) in terms of future orders. Some good points have been raised about Phantom re-engining in the posts above, but in 1957 I doubt that RR would have realistically foreseen the Spey F-4K/M or the future market for F-4 or F-104 upgrades in the 1970s. In 1957 it would not be supposed either type would outlast the 1960s. The potential market must have looked reasonably small for such a high-end military engine, although a non-reheated civil variant might have been useful in that intermediate time before high-bypass became a reality.

It would probably have killed off the Spey given that RR couldn't fund everything and that might be a shame given the commercial success of the Spey series in civil and military form, the only other RR jet that really emulated the sales success of the Avon before the high-bypass fans really took off. As good as RB.106 might have been, its hard to assume it would have had quite as many applications or been released for export to Yugoslavia and China!

I think it would have been a good replacement for the Olympus in the TSR.2 and Concorde. The ultimate Olympus versions had some serious problems, a paper design like RB.106 looks good but we can't tell what snags might have arisen. But if it had been as reliable as the Avon then a lot of development hassle and cost would have been saved on both programmes. But would the MoA take the gamble of leaving Bristol Siddeley with just Pegasus/BS.100 and small jets like the Viper and Orpheus? An earlier RR/BS merger feels likely.

A marine RB.106 also leads to some mouth watering naval what-ifs.
 

zen

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I might intrude here that the straight through Pegasus variants offered proper high bypass turbofans.
Arguably a better basis for progress than the low bypass Medway and it's scaled down version Spey.

The Viggen powered by this was looked at later on. With better fuel economy and a faster throttle than the JT8D clone used.

And as such the supersonic BS.100 as a straight through engine would be a significant development.

Along with the scaled down straight through Pegasus variant BS.75.
 

JFC Fuller

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The RB.106 appears to have had two false starts. It first appears in 1953/4 where it is the original engine for the CF-105 Arrow and is also proposed for the Supermarine Type 545. According to various CF-105 histories Rolls Royce decided to abandon development of the type in 1954, hence the change of engine in that type. There is a file at Kew that I have not read yet, AVIA 65/12 sponsorship of RB 106: financial policy, that probably contains the reason for Rolls Royce dropping it.

It then comes back to life around 1956 in scaled form for the OR.329 fighters, the much higher RB numbers indicative of the long pause (RB.122 and RB.128). Though the RB.126 for the english Electric P.8 was described as a "straightforward development or the RA.24 [Avon]" the combination of its RB number, the requirement the P.8 was designed against (OR.329) and its supposed performance characteristics (increased mass flow and turbine temperatures) makes me wonder whether it did have RB.106 DNA too.

Either way it is tantalising, the Supermarine Type 545 and the English Electric P.8 immediately come to mind as particularly interesting but any Avon powered type could potentially have been enhanced alongside other improvements (e.g. thin-wing, two-seat FAW Scimitars) whilst a scaled version could have been an option for the P.1121 if it had been adopted on an Alternative History timeline.

One of the interesting things about engines is the knock-on impacts that could be explored. For instance, RR almost killed the Bristol Olympus in 1956 by lobbying to supplant it with the Conway on the Mk.II Vulcan. It was only through pricing shenanigans that they failed. Had they succeeded, that would have potentially made the Medway the only game in town for TSR-2 and in turn it might have ended up in the Saab Viggen. Unless of course all the resource that went into the Pegasus had gone into a conventional Bristol Siddeley turbofan...
 
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steelpillow

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maybe the Bristol Type 188 and TSR.2.

Of course! In real life, when TSR-2 was cancelled BAC went to Dassault and between them they cooked up the Mirage IVK, a Mirage IV airframe with the bulk of TSR-2's avionics and a pair of Speys. The idea was to create a low-cost, reduced-spec TSR2 substitute and keep the United Kingdom's industry employed. But of course the Speys fitted the poor Mirage IV no better than they did Phantom airframe.

Over in the United Whiffdom, a couple of RB.106-es fitted the Mirage like fingers in a glove. During development the microelectronics revolution led to significant size and weight reductions in the avionics. When the Dassault/BAE Mirroir presently entered service, it was far more capable than the original Mirage and, although the airframe only met 95% of the TSR-2 spec, the avionics ore than made up for the loss. It is rumoured that the name "Mirroir" was chosen in part to reflect (sic) the active ECM capabilities which microelectronics allowed the designers to add.

Both air forces kitted out with it, the French making the RB.106 under license as the SNECMA Argentier (silverer of mirrors). Australia dropped its F-111 order late in the negotiations and also adopted the Mirroir.

The low-level Mirroir II featured a canard forward surface for nap-of-the earth manoeuvrability and significantly increased ordnance load.
 

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More additional.
Mentioned elsewhere and there discussed. Vicariously
Starfighters
Crusaders
Mirage IIIs
Etendards even.

The actual proposals for J79s and Spes do prompt musings on things like Avon and RB.106 alternatives.
Which leads to things like UK Starfighters, Crusaders and Mirage IIIs.
It also prompts a few questions such why the US didn't go back to AS for the latest Sapphire designs or their successors? Why didn't they keep relations with Bristol having licensed the Olympus?
 

Pioneer

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Would really like to seem America persist with tupobrops like that of the Pratt & Whitney T57-P-1 and Allison XT40-A-2.......


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My favorite one those days is Phillips / Kockums Stirling engine that made Sewdish SSK so formidable.

The stirling engine was invented in 1816 but stayed in limbo until 1936 when Phillips, Eindhoven, brought i back. Tooks some more decades for the Swedes (Kockums) to turn it into a viable submarine AIP system.

Whatif the nazis when they invaded Eindhoven in May 1940 gots their ugly hands on Phillips reborn AIP technology - and managed (by some nazi-wank tech scenario) to apply it to their U-boats ? (instead of Walter dangerous HTP own AIP tech). ?
 

Dilandu

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Want one submarine thing to play? Air-independent propulsion on sodium superoxide.

Sodium superoxide (NaO2) is a solid yellow crystals, produced by heating Na2O2 in oxygen atmosphere under pressure (about 100 atmospheres). It's pretty easy to store; it does not leak, does not react much. But when heated to circa 100 C, it starts to release oxygen: 2NaO2 = Na2O2 + O2

Now imagine that you build a submarine, or torpedo, that runs on a supply of sodium superoxide? It's much safer to store than pure oxygen, and could allow your diesel engine to work deep underwater, without any snorkel or other air intakes. And it could be done basically in any moment from 1900 till 1950s. Also, the product of the reaction is Na2O2 - which is used to absorb CO.

P.S. USSR tested this approach on M-361 - the last of Project 615 (NATO - Quebec-class) oxygen submarines. While the whole 615 series was considered a failure, the refitted M-361 worked surprisingly well, being perfectly safe to operate. Other works in this direction were cancelled because most efforts were pulled into nuclear submarine program.
 
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Dilandu

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Or perhaps even your silent Sterling engine.

Yep) Or even some kind of turbine, if you need REALLY FAST sub. A very elegant solution, which, unfortunately, came a decade too late; in late 50s nuclear era was at full swing, and nobody was much interested in chem boats.
 
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