Mk II Westland Whirlwind ‘What if’

Sigh…..What might have been.

😎

Hi Jerry

As for “What If?” developments of the Peregrine-powered Whirlwind, Rolls bench tested the Peregrine at 12 lbs boost and extracted over 1000 hp from it. This configuration was also flight tested in the summer of 1940 in one of the 3 Whirlwinds used by 25 Squadron for operational trials. Rolls also tested another Whirlwind at Hucknall with fin-and-tube radiators and external, straight down carburettor air intakes – in this form they clocked the aircraft at 362 mph (vs 338 for the standard article). Ultimately though the Whirlwind didn’t really need more sea level power – on the deck it was the fastest aircraft in the RAF inventory when it entered service – what the Peregrine really needed was a new supercharger to address its lamentable performance at altitude.

Niall

Hi Naill,
Thanks for the reply and comments, so the allison V1710 was an earlier idea, pity no drawings seem to be around.

I never really understood why the R-R mod’s were not incorporated, the a/c was just sent to westlands to restore back to normal config, (no front line squadron trials).

Cheers
Jerry

P.S sorry for the red thumb don’t know where it came from !!!

Allison Whirlwinds?

But back to what if’s, what american engine was it being considered,
Beaverbrook states in a letter, 27 Oct 40,
…..there was an alternative proposal to fit american engines……

Seem to recall when I wrote to westlands( in the 90’s) they hadn’t heard about it.

So What If …
allison V1710 C-15 ,Wright R-1820 or Pratt & Whitney R-1830

Westlands were preparing ‘…Hawk’s’ for service use, I think in late 1940, so they would have had a few engines around…
cheers
Jerry

Hi Jerry

The American engine proposed for the Whirlwind was the Allison, but this proposal predates by a couple of years Beaverbrook’s comments about it in 1940 (or Westland’s involvement with the P40).

When the Operational requirement F.18/37 for a new 8-12 gun fighter to replace the Spitfire and Hurricane was initially discussed Wilfrid Freeman thought it was not worth pursuing as it did not represent a great enough advance on the performance of the Whirlwind. The Whirlwind – which had not yet flown – was forecast (mainly by the ever-optimistic Petter) to have a top speed of 370-380 mph whereas F.18/37 asked for 400. Freeman took the step of commissioning an alternative 12-Browning gun nose from Westland (which project was later given to Martin Baker) so that the Whirlwind could be made at least partially compliant with F.18/37. Petter appears to have proposed the Allison at this point to make the aircraft’s projected performance fully compliant with F.18/37. At the time – and for some while later – Petter was absolutely convinced that the compact, highly-loaded Whirlwind would require handed engines which rather limited the possibilities if more power than the Peregrine was needed. In the end when the tendered designs for F.18/37 were evaluated, none of the twin-engined offerings appeared to offer any real advantage over a single engined-design and the Air Min accordingly ordered prototypes of the Tornado/Typhoon.

As for “What If?” developments of the Peregrine-powered Whirlwind, Rolls bench tested the Peregrine at 12 lbs boost and extracted over 1000 hp from it. This configuration was also flight tested in the summer of 1940 in one of the 3 Whirlwinds used by 25 Squadron for operational trials. Rolls also tested another Whirlwind at Hucknall with fin-and-tube radiators and external, straight down carburettor air intakes – in this form they clocked the aircraft at 362 mph (vs 338 for the standard article). Ultimately though the Whirlwind didn’t really need more sea level power – on the deck it was the fastest aircraft in the RAF inventory when it entered service – what the Peregrine really needed was a new supercharger to address its lamentable performance at altitude.

Incidentally I’ve lost count of the number of times I’ve read that the Peregrine was “unreliable”, but I’ve never seen any data provided to support the assertion. Most of the “engine failures” in service appear to have been nothing of the sort – in most cases they were caused by fuel shortage or problems with the wretched Exactor controls.

Niall

Better Things to Do at Yeovil than Weird Whirlwinds.

After March,1938, Austrian Anschluss, we knew War would happen, we thought in 1941. Pistoneers were stumbling over Big-Power: ASM Tiger had hurt Whitley, Deerhound killed its Super; Fairey, Curtiss D-12 1924 licensee, had failed to put P.24 Monarch (1935-designed) in Barracuda. Napier Dagger (1930) despoiled HP Hereford while Sabre(1936) slashed Hawker P.1005 High Speed Bomber, glider-prototype scrapped 3/7/42. Even trying for Small-Power, Alvis and DH derivatives (Leonides, Gipsy 12) were drifting. Crucial types were absent for engine-related causes: example: a common Hawker airframe with whichever might work from 3 big engines initiated in 1937:
– Hawker “B” – Centaurus in Tempest II: both intended to be built by Bristol;
– Hawker “N” – Napier (Acton) Sabre, in (to be)Typhoon and Tempest V, built at Kingston; .
– Hawker “R” – Tornado at Avro/Yeadon: RR Vulture (Derby); then flirted with Fairey P.24.
A.M did not plan to buy 8xgun,fabric-skin,1934-designed Hurricane in ’44: 12xguns or 4xcannon were wanted, but Vulture flayed Tornado, Sabre delayed Typhoon to late-42. A.M. did not plan to buy 1933-designed Wellington in ’45, but Vickers’ Medium, Warwick -1935, with Vulture; -1939, Centaurus; useable only after ’41 with P&W Double Wasp, by then “free” under Lend/Lease. Centaurus was so vital that MAP 5/40 would explore licenced production by GM and in Canada, and dug the grotesquely expensive troglodyte site, Corsham, for it.

RR nearly stifled 2 war-winners: Merlin delay was a factor in A.M.’s 1938 plan to terminate Spitfire and put (Hercules)/Beaufighter in Supermarine; Vulture shortfalls caused MAP July,’40 to plan to discontinue Avro Manchester and to build Halifax in Chadderton. The HP design had been for 2xVulture; in August,’37 A.M. had substituted 4xMerlin, and by September,40 did the same at Avro, (to be)Lancaster. Dumping Exe, Peregrine, Vulture, was essential, to release production capacity for Merlins, design for Griffon.

Freeman, 1937 selector of deficient engines, despaired of them all. The Westland resource was better applied to Seafire, to liberate Joe Smith to do Griffon/Spit.

Mmm, I think that Mensforth my well have been referring to the high altitude fighter that was being developed at Yeovil at this time. Westland were given the go-ahead to produce two Merlin XX prototypes on January 9, 1941. Its quite possible that in Mensforth’s eyes, this aircraft was a highly developed Whirlwind.

AlertKen, where are you? 😀

Best wishes
Steve P

Hi
Sorry for poaching into the thread again,
But the spec’s mentioned by menesforth in the letter don’t match the welkin.

the letter mentions
merlin XX, 410 Mph, 37,000′, range 800 miles.

welkin
the two 9 jan prototype a/c were originally two crew
( changed on 13-feb-41 to one pilot )

merlin 61, 383 Mph, 44,000′, range 1,480 miles

I often wonder if there was a design in between the whirlwind and the welkin….
… which may have been basically a merlin XX whirlwind, incorporating the whirlwind II mod’s,( i.e. extra fuselage fuel storage [another 60 gallons] and the new gun nose)….

But back to what if’s, what american engine was it being considered,
Beaverbrook states in a letter, 27 Oct 40,
…..there was an alternative proposal to fit american engines……

Seem to recall when I wrote to westlands( in the 90’s) they hadn’t heard about it.

So What If …
allison V1710 C-15 ,Wright R-1820 or Pratt & Whitney R-1830

Westlands were preparing ‘…Hawk’s’ for service use, I think in late 1940, so they would have had a few engines around…
cheers
Jerry

What if Kestrels were fitted instead of Peregrines, the Peregrine was a development of the Kestrel IIRC.

Cheers

Cees

Peregrine

General characteristics
 Type: 12-cylinder supercharged liquid-cooled 60 degree Vee aircraft piston engine
 Bore: 5 inches (127 mm)
 Stroke: 5.5 inches (140 mm)
 Displacement: 1,295.9 in³ (21.24 L)
 Length: 73.6 in (1869 mm)
 Width: 27.1 in (688 mm)
 Height: 41.0 in (1041 mm)
 Dry weight: 1,140 lb (517 kg)
Components
 Valvetrain: Overhead camshaft
 Supercharger: Gear-driven centrifugal type supercharger, single speed, +9 psi boost
 Fuel system: Downdraught carburettor
 Fuel type: Petrol
 Cooling system: Liquid cooled, 70% water/30% Ethylene glycol
Performance
 Power output: 885 hp (660 kW) at 3,000 rpm, +9 psi boost (bmep = 180.3psi)
 Specific power: 0.68 hp/in³ (31.1 kW/L)
 Compression ratio: 6:1
 Power-to-weight ratio: 0.77 lb/hp

Kestrel

General characteristics
 Type: Supercharged liquid-cooled 60-degree V12 engine
 Bore: 5 in (127 mm)
 Stroke: 5.51 in (140 mm)
 Displacement: 1,297 in³ (21.25 L)
 Width: 24.41 in (620 mm)
 Height: 35.63 in (905 mm)
 Dry weight: 957 lb (434 kg)
Components
 Valvetrain: Two inlet and two exhaust poppet valves per cylinder
 Supercharger: Gear-driven centrifugal type supercharger
 Fuel system: Rolls-Royce carburetor
 Fuel type: 87 octane rating gasoline
 Cooling system: Liquid-cooled, pressurised to 300°F (150°C)
 Reduction gear: Spur, 0.553:1
Performance
 Power output:
 685 hp (511 kW) at 2,240 rpm for takeoff
 631 hp (471 kW) at 2,900 rpm at 14,400 ft (4,400 m)
 Specific power: 0.53 hp/in³ (24.05 kW/l)
 Compression ratio: 6.0:1
 Oil consumption: 0.18-0.35 oz/(hp•h) (7-13 g/(kW•h))
 Power-to-weight ratio: 0.72 hp/lb (1.18 kW/kg)

I’ve seen somewhere that the Kestrel could/had produced 1050hp at one point… :confused:

Can anyone confirm that?

What if Kestrels were fitted instead of Peregrines, the Peregrine was a development of the Kestrel IIRC.

Cheers

Cees

We’re beginning here to get away from what could have been done to the Peregrine & existing airframe to make a viable Mk II variant.

So please gentlemen lets not start on a Merlin power Whirly roll again, think of how the Peregrine could be improved, to be less of an asthmatic sprinter always running out of breath before the finishing line! But turn it into a deep chested micro power house… After all Rolls Royce did in the end start to patch up its big brother, the Vulture! And with proposed alterations (Never implemented) could have been a better option than the Sabre, but with the Merlins being an easier path, it ended up being skip fodder!

So, if time and money was available, could the Peregrines have been brought up to 1000-1100 hp and still be, within reason near the same weight and proportions of the standard engine… With 4 blade prop’s, extra fuel capacity, crossover feed systems and superior weapons fitted, would extra power have still been an advantage or would the extra weight negate any benefit the Mk II Peregrine would give the little Whirlwind…

Hi Jerry

Hmmm, well he might have written about fitting Merlins, but when I asked Fred Ballam about this, he told me he had never found anything on paper as to how exactly it was to be done… 🙁

Idea’s anyone…

Mmm, I think that Mensforth my well have been referring to the high altitude fighter that was being developed at Yeovil at this time. Westland were given the go-ahead to produce two Merlin XX prototypes on January 9, 1941. Its quite possible that in Mensforth’s eyes, this aircraft was a highly developed Whirlwind.

AlertKen, where are you? 😀

Best wishes
Steve P

Sorry if this has been suggested before, but surely another reason why the Merlin was not used or seriously considered in the Whirlwind was because there simply were not enough to go round.. Spitfires, Hurricanes, Battles, Lancs etc all taking up what RR were manageing to produce. I doubt if another ‘possible’ customer for the merlin would ever have been entertained?!:confused:

Hi

My favourite stock answer to the many whirlwind / merlin engine debates.

Following extract not from a ‘ what if ‘,
but from genuine preserved correspondence…

Jan 41 in a letter to Sholto Douglas
by Eric Mensforth M.D. Westlands.

……. We are now able, because of the solution of certain undercarriage retraction problems, to offer to install in the whirlwind twin merlin XX engines …..

Therefore in answer to all the long standing internet debates, Westlands in 1941, put in writing that the whirlwind airframe could handle merlin engines..

Cheers
Jerry

Hi Jerry

Hmmm, well he might have written about fitting Merlins, but when I asked Fred Ballam about this, he told me he had never found anything on paper as to how exactly it was to be done… 🙁

Idea’s anyone…

Nice one – thank you – my own resource is somewhat limited in comparison, I was looking at “interceptor” by James Goulding which quotes pretty much what I said as does Tony Buttler, but I’m guessing that has all been discussed a million times already !

What if indeed……….. thanks for the info.

Hi
I must admitt I have an un fair advantage, my whirlwind resources are extensive..
some may call it an addiction… which started in the early 70’s:D….
cheers
jerry

Hi

Therefore in answer to all the long standing internet debates, Westlands in 1941, put in writing that the whirlwind airframe could handle merlin engines..

Cheers
Jerry

Nice one – thank you – my own resource is somewhat limited in comparison, I was looking at “interceptor” by James Goulding which quotes pretty much what I said as does Tony Buttler, but I’m guessing that has all been discussed a million times already !

What if indeed……….. thanks for the info.

IIRC Merlins were too big and too heavy for the design, Petter designed the aircraft to be as small as possible – maybe an “upscale” would have worked but as discussed here on many threads by us Whirlwind lovers/what ifs etc, Westland were too small a company to do it, Spitfires etc were the order of the day – Whirlwinds & MB-5’s got lost along the way.

Hi

My favourite stock answer to the many whirlwind / merlin engine debates.

Following extract not from a ‘ what if ‘,
but from genuine preserved correspondence…

Jan 41 in a letter to Sholto Douglas
by Eric Mensforth M.D. Westlands.

……. We are now able, because of the solution of certain undercarriage retraction problems, to offer to install in the whirlwind twin merlin XX engines …..

Therefore in answer to all the long standing internet debates, Westlands in 1941, put in writing that the whirlwind airframe could handle merlin engines..

Cheers
Jerry

Petter, not Tedder. WAL not a small Co. Near-bankrupt while a branch of Petter’s, but saved 7/38 by investment by AEI Ltd (18.75%) and John Brown Ltd.(50%). Like all other 1936 Expansion equipment, design by the little parent, (intended) production by a new-entrant: Whirlwind, Castle Bromwich Aircraft Factory, run by Nuffield.

Many types disappointed at that time, due to mismatch between airframe evolution and Big Power. See Centaurus, which messed up many a Warwick.

IIRC Merlins were too big and too heavy for the design, Petter designed the aircraft to be as small as possible – maybe an “upscale” would have worked but as discussed here on many threads by us Whirlwind lovers/what ifs etc, Westland were too small a company to do it, Spitfires etc were the order of the day – Whirlwinds & MB-5’s got lost along the way.

One would need to ensure it also had fully-feathering props, a cross-feed for the fuel tanks (shakes head) and radiators re-done a la Mossie, with additional fuel tanks taking up the space where the original rads were. All of the above the might have meant a fairly big fuselage re-design, maybe longer nose and tail?

Westlands have been given the green light by the Air Ministry to produce 400 units of Mr Petters Mk II Whirlwind design. This due mainly to a deal struck between Rolls Royce & Packards to produce another 1000 Peregrine V-12 Aero engines, built under licence to Rolls Royce for use with the Mk II Whirlwind. Packards having agreed to further develop the Peregrine to produce an engine of 1000hp with improved performance & reliability… For this they would be given sole rights to produce the ‘New’ Peregrine 1000 hp V-12 Marine engine to suppliment their 1350, 1400, and 1500 horsepower V-12 units that powered American PT boats …

Petters Mk II now fitted with a couple of reliable Peregrine’s kicking out 985hp each, a new propeller with greater pitch, an extra 35gallon fuel tank and a new nose with room for four 20mm cannon with continuous feed, 120 rpg, plus an extra three 0.303-in Browning guns with 400 rpg…

What job would you give this little ‘She Devil’ now… 😉

Why bother to carry on with development of the Peregrine – just fit a couple of Merlins and use it as a long range, high performance, cannon armed fighter – the de Havilland Hornet of its’ day

Middle East/Malta & long range fighter sweeps into Europe, maybe escort the Banff wing Mossies/Beaus as well?