Those are the hard facts and choices of production, the 301 Peregrine engines produced probably cost Rolls Royce 600-900 in lost Merlin production, so the RAF got two squadrons of Whirlwinds, lost the engines for at least 600 S/E fighters and Rolls Royce lost money on the whole thing. It is very difficult to rationalise production when you are making more than one product.
Westland Whirlwind in Battle of Britain
- Thread starter Admiral Beez
- Start date
Shortround6
Lieutenant General
Not without a time machine.
The old retroscope is clearly working!
It wasn't until 18th July 1940 that de Havilland was instructed to finish one prototype as a fighter.
The only version that could be considered a day fighter was the F. Mk II which was described as a day and night long range fighter and intruder (a word that came into vogue in 1941) and first flew on 15 May 1941. Most of these aircraft were refurbished for operations with 100 Group, obviously not as day fighters. Others were converted for PR duties. The Mosquito never operated as a day fighter in a meaningful way, and with very good reason.
Shortround6
Lieutenant General
Sort of the same reason the Grumman F5F skyrocket got those huge Wright Cyclone engines. P&W stopped development of the promised two stage supercharged R-1535 engine, in fact P & W stopped any and all development of the R-1535 engine to concentrate on the R-1830 and R-2800.
The R-1535 was simply too small to make the needed power new aircraft designs demanded.
Junkers canned the Jumo 210 for about the same reason.
yulzari
Tech Sergeant
So why did Rolls Royce make the Peregrine in the first place?
It was a development on from the Kestrel, allowing more boost, the Vulture was also a development being 4 banks of Kestrel/Peregrine cylinders. Things moved on quickly, the Kestrel Peregrine type engine was just too small for designs that were emerging.
Shortround6
Lieutenant General
Because it could be made with a lot of the tooling used for the Kestrel.
I don't know when it was first proposed or test run but British aircraft development in the mid to late 1930s seemed to be like trying to jog through Portland harbor mud.
The Kestrel had been the big money maker for RR during the late 20s and up until the mid 30s (4750 built) , offering an updated version should have seemed like a no brainer.
However the market was shifting and what planes could have used the moderately sized engine took too long to develop.
And the Merlin took over the top spot (Buzzard and paper Griffons of the 1930s being a little too much of a stretch for the airframe designers.)
Bristol fell into the same hole with the Taurus. yes it offered several advantages over the Pegasus but not enough to give planes powered by it a big advantage and it was too small to power the larger planes the Hercules could power.
Companies were desperate coming out of the depression years and were trying to offer a broad selection of "products"for the aircraft designers, but they were trying to see 2-4 years into the future.
Had the war not come would the commercial airlines have been asking for 1400-2000hp engines in the early 40s or would they have been happy with 1000-1500hp engines?
P&W got it right with when the stopped the R-1535 and then got it wrong less than 10 years later when they built the R-2180 which was 1/2 of the 28 cylinder R-4360. The Airlines that could afford new planes wanted 2000hp engines (R-2800s) and the ones that couldn't afford new planes bought surplus C-47s, C-46s and C-54s leaving P & W with no market for the R-2180.
I don't know when it was first proposed or test run but British aircraft development in the mid to late 1930s seemed to be like trying to jog through Portland harbor mud.
The Kestrel had been the big money maker for RR during the late 20s and up until the mid 30s (4750 built) , offering an updated version should have seemed like a no brainer.
However the market was shifting and what planes could have used the moderately sized engine took too long to develop.
And the Merlin took over the top spot (Buzzard and paper Griffons of the 1930s being a little too much of a stretch for the airframe designers.)
Bristol fell into the same hole with the Taurus. yes it offered several advantages over the Pegasus but not enough to give planes powered by it a big advantage and it was too small to power the larger planes the Hercules could power.
Companies were desperate coming out of the depression years and were trying to offer a broad selection of "products"for the aircraft designers, but they were trying to see 2-4 years into the future.
Had the war not come would the commercial airlines have been asking for 1400-2000hp engines in the early 40s or would they have been happy with 1000-1500hp engines?
P&W got it right with when the stopped the R-1535 and then got it wrong less than 10 years later when they built the R-2180 which was 1/2 of the 28 cylinder R-4360. The Airlines that could afford new planes wanted 2000hp engines (R-2800s) and the ones that couldn't afford new planes bought surplus C-47s, C-46s and C-54s leaving P & W with no market for the R-2180.
To avoid arguments about various means of splitting engines, you could point out that the Typhoons stable mate the Tornado had the Vulture engine that was basically two Peregrine engines running on a common crankshaft. The Vulture used 4 banks of 6 cylinders and the Peregrine used 2 banks of 6.
fastmongrel
1st Sergeant
The Vulture wasn't two Peregrine's. There was hardly any parts crossover the blocks and heads were a different cylinder spacing, the pistons might have been similar but that's about it.
Shortround6
Lieutenant General
Valves, valve springs, etc, even if the cams were different, but that may have been the same or similar cam lobes spaced out more on the shaft.
I was speaking of the general principle not advocating swapping parts. The Peregrine and Vulture had the same bore and stroke and same valve arrangement if not the same timing. When you double the cylinder banks you must increase the bearing area and so increase cylinder spacing. The Tornado and Whirlwind are comparable aircraft in terms of the cylinders of the Whirlwind being joined on a single crankshaft. It wouldn't be advisable to swap engine parts from a 1938 Spitfire Mk I to a 1944 Mk IX even though they are both named "Merlin" Rolls-Royce Engines: Peregrine - Graces Guide
During the 1930s the use of superchargers to increase the effective displacement of an aircraft engine came into common use. Charging of some form was a requirement for high-altitude flight, and as the strength of the engines improved there no reason not to use it at all times. The introduction of such "ground level" supercharger to the Kestrel along with several design changes improved the power-to-weight ratio considerably, and it was generally felt that the resulting Peregrine would be the "standard" fighter engine for the upcoming war. Two Peregrines bolted together on a common crankshaft would produce the Rolls-Royce Vulture, a 1,700 hp X-24 which would be used for bombers.
During the 1930s the use of superchargers to increase the effective displacement of an aircraft engine came into common use. Charging of some form was a requirement for high-altitude flight, and as the strength of the engines improved there no reason not to use it at all times. The introduction of such "ground level" supercharger to the Kestrel along with several design changes improved the power-to-weight ratio considerably, and it was generally felt that the resulting Peregrine would be the "standard" fighter engine for the upcoming war. Two Peregrines bolted together on a common crankshaft would produce the Rolls-Royce Vulture, a 1,700 hp X-24 which would be used for bombers.
- Thread starter
- #32
Admiral Beez
Major
Imagine the Peregrine as a replacement in Kestrel-powered aircraft, like the Hawker Nimrod.
I wonder if the Peregine's tooling would have been useful to making iron block truck or A/IFV engines. Like a smaller, earlier Meteor.
Rolls-Royce Meteor - Wikipedia
The Meteor was developed from the Merlin by W. A. Robotham and his chassis design and development division at Clan Foundry, Belper, as they were not involved in aero-engine work and his engineers were under-used. With the aid of engineers from Leyland, who were engaged in tank work, he considered RR's two V12s; the Kestrel, while having more power than the existing "Liberty" or Meadows engines, did not provide the desirable 20 bhp per ton required, so the 1,030 bhp (770 kW) Merlin III was chosen. Robotham was at pains to point out that Rolls-Royce could not manufacture the engines, so would not benefit commercially.
Clearly the Peregrine would go into lighter applications than the Meteor.
I would think that the Peregrine Kestrel Merlin and others had the same tooling until war was declared. They were all made in the same factory. Production of Kestrels and Peregrines averaged about 2 per day from start to finish.
wuzak
Captain
The only problem with that is the Vulture program started before the Peregrine program, The Vulture ran before the Peregrine and was in production earlier.
It that sense it may be more correct to describe the Peregrine as being, essentially, half a Vulture.
Petter did draw up a Mk II with American Twin Wasp engines using 100 Octane fuel, though these might have had the same altitude issues as the RR Peregrine if they didn't have the right supercharges, but the Air Ministry rejected the idea. A Twin Wasp Whirlwind was projected to have a 380mph top speed and would have been interesting as it would have given the RAF a long-range fighter suitable for use in North Africa and the Far East in 1941.
The Westland Whirlwind had a better climb rate at low level than the Spitfire MkIa and Hurricane MkI, and was as fast as the Spitfire at 16,000ft, which was the typical height for Luftwaffe bomber raids in 1940. So the Whirlwind would have got up to the combat level faster and had the speed to chase down the enemy. It had much better visibility and offered the chance of a deadly punch with the four cannon. However, it would have required top cover from the Spitfires to protect it from high-flying 109s, just like the Hurricane. It would probably have been more effective than the Hurricane as long as the pilots could aim straight, otherwise the scatter-gun .303s of the Hurricane presented a better solution than the four cannon with only six seconds of firing time. As regards dogfighting with the ME109E-4, the Whirlwind tangled with late-model Es in 1941 and later with FW190s, so it should have done OK.
What the Whirlwind does offer is the option of low-level sweeps and attacks on the German airfields, a task that was left to Blenheims and Fairy Battles.
As I understand it the kestrel and Peregrine cylinders and heads wer the same, the difference being in strengthening of the bottom end, but the thread is about Whirlwinds.
"...I really do not think these troubles have been any worse than they were on, say, the Spitfire."
They were a lot worse than on the Spitfire.
Collapsed canopies.
Collapsed tail wheels, at best with damage to the tail wheel doors and wooden fairing at the base of the rudder, at worst with a fracture to the bulkhead casting at the base of the fin spar (to which the tail wheel was mounted) and the rudder hinge casting higher up the fin. Over 150 instances were recorded, a problem that was never properly solved by Westlands and the number one cause of unserviceability.
Fatal accidents caused by failures of the outer slats, which were wired closed as an expedient.
Re-set of pitch range of propellers to prevent over speeding in a dive.
Undercarriage mudguards detaching, damaging nacelles and/or propellers (they were eventually deleted).
Failure of welds in carburettor intake ducts.
Wing tip failures (13 Group's Engineer Officer grounded the type until Westlands supplied reinforced wing tips).
Shell ejection problems and damage to aircraft nose during gun firing trials (a crude reinforcement for the nose was devised by 263 squadron).
Fracture of hydraulic pipes.
Change to pneumatic from hydraulic cannon firing system.
Canopy perspex developing cracks.
Corrosion in the cooling system.
Erratic operation of the boost control. Failiure to maintain the rated boost during a climb. An investigation proved that the gauges and pipes in the system all leaked
In September 1940, when some would have hoped to have the type flying in the BoB the aircraft's serviceability rate was just 55%.
In October and November 1940, in the face of these and other problems I haven't mentioned, Westland, the MAP and the Air Ministry all suggested that the Whirlwind's technical problems would be more easily addressed if 263 squadron were moved to 10 Group and the South West of England, nearer to Yeovil. Dowding was reluctant to do so. He told the Air Ministry
"The squadrons in 10 Group have a considerable amount of fighting to do and must be in a fully operational condition."
He was more blunt with Beaverbrook and the MAP
"I purposely put 263 squadron well out of the way because I know Westlands and I know what a packet of trouble the squadron would be in for. I cannot put them anywhere in the South because I cannot carry any passengers in that part of the world."
The MAP loaned a de Havilland Rapide to transport urgently needed Whirlwind spares to Scotland and Dowding kept the Whirlwinds out of the way. On 28 November the squadron did move, to Exeter.
The first operational flight of a Whirlwind was on 7 December 1940, and even that required an element of determination and luck from the men at 263 squadron. Dowding had predicted 'an infinity of trouble' with the Whirlwind and he certainly got it, starting in July 1940, the first occasion on which the type was grounded, just as the Battle of Britain was starting to gain pace.
They were a lot worse than on the Spitfire.
Collapsed canopies.
Collapsed tail wheels, at best with damage to the tail wheel doors and wooden fairing at the base of the rudder, at worst with a fracture to the bulkhead casting at the base of the fin spar (to which the tail wheel was mounted) and the rudder hinge casting higher up the fin. Over 150 instances were recorded, a problem that was never properly solved by Westlands and the number one cause of unserviceability.
Fatal accidents caused by failures of the outer slats, which were wired closed as an expedient.
Re-set of pitch range of propellers to prevent over speeding in a dive.
Undercarriage mudguards detaching, damaging nacelles and/or propellers (they were eventually deleted).
Failure of welds in carburettor intake ducts.
Wing tip failures (13 Group's Engineer Officer grounded the type until Westlands supplied reinforced wing tips).
Shell ejection problems and damage to aircraft nose during gun firing trials (a crude reinforcement for the nose was devised by 263 squadron).
Fracture of hydraulic pipes.
Change to pneumatic from hydraulic cannon firing system.
Canopy perspex developing cracks.
Corrosion in the cooling system.
Erratic operation of the boost control. Failiure to maintain the rated boost during a climb. An investigation proved that the gauges and pipes in the system all leaked
In September 1940, when some would have hoped to have the type flying in the BoB the aircraft's serviceability rate was just 55%.
In October and November 1940, in the face of these and other problems I haven't mentioned, Westland, the MAP and the Air Ministry all suggested that the Whirlwind's technical problems would be more easily addressed if 263 squadron were moved to 10 Group and the South West of England, nearer to Yeovil. Dowding was reluctant to do so. He told the Air Ministry
"The squadrons in 10 Group have a considerable amount of fighting to do and must be in a fully operational condition."
He was more blunt with Beaverbrook and the MAP
"I purposely put 263 squadron well out of the way because I know Westlands and I know what a packet of trouble the squadron would be in for. I cannot put them anywhere in the South because I cannot carry any passengers in that part of the world."
The MAP loaned a de Havilland Rapide to transport urgently needed Whirlwind spares to Scotland and Dowding kept the Whirlwinds out of the way. On 28 November the squadron did move, to Exeter.
The first operational flight of a Whirlwind was on 7 December 1940, and even that required an element of determination and luck from the men at 263 squadron. Dowding had predicted 'an infinity of trouble' with the Whirlwind and he certainly got it, starting in July 1940, the first occasion on which the type was grounded, just as the Battle of Britain was starting to gain pace.
Last edited:
Yeah, Petter had a fixation with hydraulic systems, he even used Exactor hydraulics for the throttles instead of conventional cables. When they worked they worked, but it does seem a bit of over-engineering.
Dowding was right in that Westland and 263 Sq had not had sufficient time to develop the aircraft by the BoB, but that ignores the fact both the Hurricane and Spitfire had longer squadron development before the BoB, and both had many issues ironed out before combat, so singling out the Whirlwind as particularly bad is untrue. Hawkers was considered the Air Ministry's most experienced supplier, and one of the reasons the staid Hurricane was ordered in such large numbers was because of the suspicion that Supermarine might not be able to deliver the advanced Spitfire in numbers to an adequate level of operational reliability. Westland was a tiny firm by comparison, so it's not surprising they got short shrift.
The Whirlwind wasn't alone in having problems with pipes leaking, the Spitfire being notorious for the pipes installed for the heating air to the wing guns being prone to leaks, fractures, and even falling right out of the wings! The original Spitfire MkIa aircraft delivered didn't have any gun heating, and it wasn't until RAF operational flights took the aircraft over 15,000ft that the RAF realised that meant all the guns froze up! Thankfully, the early combats for home-based Spitfires were all low down as the heating fix wasn't in place until early 1940.
RAF fighters like the Hurricane and Spitfire also had bottles (metal cylinders) of carbolic gas as a back up system for their landing gear because pipe leakages frequently meant the landing gear wouldn't extend fully and lock. The Spitfire MkI's wings were modified to have a little metal flag that projected upwards when the undercarriage was down and locked, giving the pilot a visual indicator necessary because the cockpit indicators were electrical lights which also often failed to work correctly. Pierre Clostermann's Le Grand Cirque has a vivid description of belly-landing a Spitfire at night after both the regular and carbolic systems failed due to leaks, and that was mid-War!
Another example of early teething issues was with the Hurricane, which had originally come with a retractable tailwheel, but bad spin recovery behaviour meant that Hawkers had to put a small ridge-like fin on the underside of the fuselage exactly where the tailwheel was, leading to the fixed tailwheel. This is a pic of the prototype Hurricane with retractable tailwheel (and braced tailplane):
