Bristol Brabazon with LR1 engines

[PMN1]

"Whittle: The true story" has some pieces by Whittle in the back about the LR.1 and turbofans

The Bypass ratio of the LR.1 was to be 2.5 - 3.0 and total thrust about 6000lb. The prototype was nearly completed in 1944.

Had Whittle been able to develop his LR1, what are the chances of fitting it to the Brabazon in place of the Proteus?

 

[alertken]

Who would have funded such a thing, and why? In 1944 RAF was not clear that turbines had any role beyond dash. BSAAC/BOAC were happy with big pistons for Mark 1 Brabazon Committee Types, hesitant about Theseus/Mamba turboprops for Marks 2, highly dubious about Ghost/DH.106 Express mail carrier. Airlines are in the payload/range business: turbines offered neither, at unknown fuel/maintenance expense.

 

[PMN1]

Who would have funded such a thing, and why? In 1944 RAF was not clear that turbines had any role beyond dash. BSAAC/BOAC were happy with big pistons for Mark 1 Brabazon Committee Types, hesitant about Theseus/Mamba turboprops for Marks 2, highly dubious about Ghost/DH.106 Express mail carrier. Airlines are in the payload/range business: turbines offered neither, at unknown fuel/maintenance expense.

The UK taxpayer??

Bill Gunston says in his book 'The development of Jet and Turbine Aero Engines' is that when Power Jets was nationalised it was told it must not build another engine and the loss of the LR.1 was of no consequence. When Japan was defeated there was no need for a long range bomber so the engine was cancelled - a few weeks alter the spec for the B35/46 long range bomber was issued.

 

[alertken]

LR.1/T.167 Brabazon

Because it made no sense to duplicate, thus unemploy, taxpayers' investment in Bristol/Napier/RR's Production Groups, Whittle's team became an experimental site in April,1944. He had no monopoly of ideas, nor had he a wand to turn notions into reliable product. Griffith's axials, via MetroVick, were berthed in March,1947 at ASM: with all the resources of HS Group and (ex-Power Jets) NGTE, it took until late-1957 to turn F.9 into Sapphire fit-for Victor. Owner initiated BE.10 late-1946, not fit-for-Vulcan until late-1956. US in 1942 funded GE on turboprop, Westinghouse on turbojet, Allis-Chalmers on turbofan - hefty Corpns. expert at power generation, yet all failed. Just like Bristol had taken forever to make Centaurus fit-for-service, Napier, ditto Sabre, RR...well, they never did on pistons bigger than Griffon, and that took awhile. LR.1 (and PCB/turbofan W.2/700, and more schemes besides) were parked to liberate effort and metals to address 1945's needs. Those were seen as including big turboprop Clyde/Tweed/Theseus. All failed.

If LR.1 had run on an NGTE bench early-1945...it would not have found a berth. In 1946 Bristol sold, not BE.10 but a Theseus upgrade (to be Proteus) into Mark II T.167 to follow Centaurus Mk.I, and Saro chose Tweed for SR.45 (to be Princess). Attlee's interest in a Bomb was inspired by Sen.McMahon 1 August,1946, but not until January,1947 did RAE accept that UK industry was capable of carrying a 5 ton Fat Man 50,000ft./1,500nm., such that MoS could put out the Medium Bomber tender. Napier were seen as incapable of powering that with turbofan E.113 (ultimately RB.80 Conway). Big axials, well-resourced at ASM/Bristol, would be challenge enough.

Vickers and Avro schemed various Brabazon Type III notions, 1946-47, with turbojets x4, x6. The Corpns. wanted nothing to do with any of them. Not until, what: 1959 turboprops, 1960 turbojets, 1962 turbofans, were hot turbines even half fit for long sectors at airline intensity. Wright invented R-3350 turbo-compound piston long after LR.1 was schemed, and sold it into DC-7C/L-1649 long after Proteus had flown. Airlines needed reliability, cost stability NOW please, not speed erratically, sometime, maybe.

 

[PMN1]

As but you are talking 'as was'. i'm wondering if the LR1 could have been fitted to the Brabazon and if so how many would have been needed and what kind of performance could you expect.

Whittle seems to have designed the turbofan long before anyone else but was held back by political moves within the aero-engine industry.

What surprises me is the US didn't take advantage of the UK government virtually throwing the turbofan out of the window.

 

[alertken]

LR.1/T.167 Brabazon

Now we know modest-BPR turbofans (Spey/Conway, JT3D/JT8D) are good things, where economy/reliability are prime. Stovepipes retain the market for sheer grunt: in 1945-48 that was most markets. RR Chief Scientist, ex-RAE axial inseminator Griffith, was given E.113 in 1947, but with junior priority until AJ65 (Avon) was fixed. Pratt did J57 turbojet at the same time, for the same reason: buyers wanted fighter dash, not trundle economy. Griffith/Conway's chance came on 1950 target-marker Valiant B.2, intended as prime purchase, displacing Avon/B.1; its deletion was to release resources for Avon-in-everything-Korean. Resurrected 1955, few saw any benefit over proven Olympus Mk.101, but MoS bought it for Victor B.2 as tightly-priced insurance for Olympus Mk.201/Vulcan B.2. It won some DC-8-40/707-400 business, so inspired a quick-and-dirty J57/JT3C bolt-on, to be the renowned TF33/JT3D.

Sure it would have been good if some soothsayer in 1945 could have anticipated all that. But UK/US wisdom was that big pistons would do long range, little turboprops would do medium, and turbojets would do pointy, noisy. We became blase about 10,000hr TBO by c.1975 (>30,000hr on majestic metallurgy in today's high-BPR products), but in 1945 the 100hr type test was as far off as the moon.

EE sold their Napier turbofan to RR as they could see no market. Nobody moved to hold back a profitable, wanted Whittle.