Did The Prop Doom The Westland Whirlwind?

[MIflyer]

The following link has a well done article on what the real problems were with the Westland Whirlwind.

The Aviation Historian - Issue 20 : Free Download & Streaming : Internet Archive

And this link has the 1938 technical paper referenced in the article.

https://ia802707.us.archive.org/29/...19930091714/NASA_NTRS_Archive_19930091714.pdf

I found all this fascinating and quite informative.

 

[Greyman]

While there's no doubt numerous improvements could have been made to the Whirlwind - we have what 'doomed' the Whirlwind in black and white from the powers-that-be themselves: engine rationalization.

 

[swampyankee]

While I think the Whirlwind had a lot of potential, the Peregrine wasn't much easier to produce than the Merlin, and one could probably produce five Spitfires for the same effort as three Whirlwinds (engines were a major part of aircraft cost at the time, as much as 40%) and they could do essentially the same mission.

 

[stona]

Well it wasn't as manoeuvrable as a Spitfire, it was far from viceless, and the leading edge slats had to be wired shut. Not a promising start.

The propeller part is very interesting, but nothing would have saved the Whirlwind.

Quite apart from the issues with the engines, Rolls Royce, Westlands and the Air Ministry, the woes of the aircraft's introduction at squadron level are best described in Robert Bowaters '263 and 137 Squadrons - The Whirlwind Years'.

Cheers

Steve

 

[Shortround6]

This is what fatally wounded the Whirlwind

The rationalization of engine production was just the final blow.

The overwhelming need for an aircraft that would be found totally useless for modern warfare by the end of June 1940 pushed the Whirlwind to the back burner for too long and catching up could not be done in the desperate days of summer and fall of 1940.

To have had any real chance the Whirlwind needed to be sorted out and in at least some sort of production in 1939 but the Lysander had priority.

 

[stona]

It wasn't just the Lysander that held up the Whirlwind.

In March 1938 work on the first prototype more or less ceased because Rolls Royce (which testing two pairs of Peregrines for the Whirlwind and the second Gloster F.9/37 prototype) didn't have the engines ready. They arrived at the end of April and beginning of May. The Peregrine II didn't finish its full type test until July, and was then installed in Rolls Royce's He 70 for endurance tests.

In August it was decided to replace the mechanical engine controls with Exactor units...more delay.

The same month a crack in the casting forming one of the fuel tank walls meant that the outer wings had to be removed and a new tank installed. This created another delay of nearly a month.

There were many more.

In July 1938, before those additional delays, Sholto-Douglas told Freeman that deliveries to the RAF might start in June 1940, which seemed "an unnecessarily long time to produce an aircraft designed early in 1936". He also suggested that Westland should be helped to expand its capacity or that another company be brought into the Whirlwind programme. Verney objected to bringing in another company, citing the problems of sub-contracting work on the Spitfire. He insisted that the aircraft should be in production by Westland and that final production proved drawings could be issued. Lemon thought that another company would have to be involved. "If the F.37./35 is required in any quantity , it would be beyond the capacity of Westlands. Their shops are poorly equipped and their is insufficient labour in the district."

This last point is important. A shortage of skilled labour plagued the British aircraft industry (and RAF which could not simply take skilled men from industry). In August 1938, before the take over by John Brown, the company employed just 726 productive workers (about a fifth the number employed by Bristol). The company was involved in not just Lysander production, for which it sub-contracted 13% of the production man hours, but the Hurricane (35% sub-contracted) and Spitfire (60% sub-contracted).
Westland was based at Yeovil. It was and still is a largely rural area, sparsely populated and better known for fruit and dairy farming. It was not an area where a skilled industrial work force could quickly be found.

It's still remote today, and there was no M5 in 1938!

There were a lot of things stacked against Westland and the Whirlwind, the Lysander was just one of them.

Cheers

Steve

 

[Shortround6]

True but at times they were cranking out 5-7 Lysanders a week.

Many British firms/factories had problems running multiple programs at the same time.

The Whirlwind ran into an almost perfect storm of problems of which next to none had anything to do with basic design/concept.
And due the excessive delays in the program it fell behind what was thought to be obtainable in other ways (four cannon Hurricanes, four cannon Spitfires and Typhoons) and was canceled before some these proved to be less than optimal solutions until they too, had extended periods of development (or short comings in Performance=Hurricane IIc).

 

[michaelmaltby]

".... the program it fell behind what was thought to be obtainable in other ways ..."
That and the Peregrine Program.
But ... since, "Necessity is the Mother of Invention" ... had the Whirlwind gone into mass production deploymnent, what under-served niche would it have fulfilled? It was hardly stellar during the Chanel Dash. Could it have packed two big canons on the nose and replaced the Hurricanes in N Africa? 2 engines are a plus in CAS platforms, no?

 

[Shortround6]

It could have had a go at replacing that wonder plane of the era, the Hawker Typhoon.

250 square ft of wing 8310lbs empty and 24 cylinders vs

279 sq ft of wing, 8840lbs empty and 24 cylinders

Typhoon doesn't carry 1000lb bombs until well into 1944?

I would note that not much of anything performed in a Stellar fashion during the channel dash except the aircrew.

 

[stona]

... had the Whirlwind gone into mass production deploymnent, what under-served niche would it have fulfilled?

It wasn't intended to fill a niche at all.

F.37/35 is explicitly for a "day and night fighter" which can fulfill various conditions, the first and foremost of which were to have a speed at least 40 mph faster than "the contemporary bomber" at 15,000 feet and to "have a sufficient number of forward firing 20mm or 23mm calibre guns to effect a decisive result in a short space of time and from longer ranges than is possible with machine guns".

That means that it was primarily intended as an air superiority fighter and bomber interceptor.

Edit: I should mention that the first versions of the specification called for a single engine aircraft, but this was dropped in the later version issued to the aircraft industry (specifically Armstrong-Whitworth, Fairey, Hawker, Vickers and of course Westland).

Cheers

Steve

 

[Dimlee]

Let me just peek in and say that this is another promising thread. Thanks for topic starter and participants.
I know too little about the subject to contribute but Whirlwind is so sexy... No, like that - so sexy that I am eager to read everything.
Now I shut up and switch back to listening mode.

 

[michaelmaltby]

".... I would note that not much of anything performed in a Stellar fashion during the channel dash except the aircrew."
Herr Galland might argue that point with you

 

[MIflyer]

I think of the Whirlwind when I see this twin-engined P-40. But the P-40 twin has two Merlins, which seems more than a little excessive. Something smaller would seem more likely, like the V-770 Ranger, another failure.

 

[stona]

The Merlin Whirlwind was proposed by Petter, by-passing the normal chain of command, directly to Sholto-Douglas. It was a last ditch effort and there is no evidence that Westland had really solved the problems of fitting the Merlin in the aircraft, particularly the extensive redesign of the nacelles and landing gear attachments that would be needed to accommodate the Merlin's up draught carburettor.

I think Bowater had it about right when he wrote:

"Had the aircraft been ordered off the drawing board, delivered on time, and had the engine not been cancelled, the RAF would have had several squadrons of Whirlwinds during the Battle of Britain. The carnage they would have caused amongst the Luftwaffe bomber formations can only be imagined but, as it was, by the time the aircraft became operational at the end of 1940, the majority of combats took place at 20,000 feet plus, well above her operational ceiling. The Whirlwind had missed its raison d'être, but the two squadrons who operated them against the enemy made excellent use of them in a different role – that of ground attack."

The point about the engines is important. When the first Peregrine engine was delivered the decision had already been taken to cease production after just 290 units. From that point the Whirlwind was doomed, it was just a question of how many, if any, Whirlwinds would be produced. The eventual 114 is about as many as was ever going to be possible.

I'm not sure about the carnage either. Yes, the Whirlwind was armed with four 20mm cannon, but with just 60 rounds for each, that's roughly two three second bursts. The armament was not as reliable as the pilots would have hoped either.

Cheers

Steve

 

[Shortround6]

The Merlin Whirlwind was proposed by Petter, by-passing the normal chain of command, directly to Sholto-Douglas. It was a last ditch effort and there is no evidence that Westland had really solved the problems of fitting the Merlin in the aircraft, particularly the extensive redesign of the nacelles and landing gear attachments that would be needed to accommodate the Merlin's up draught carburettor.

The point about the engines is important. When the first Peregrine engine was delivered the decision had already been taken to cease production after just 290 units. From that point the Whirlwind was doomed, it was just a question of how many, if any, Whirlwinds would be produced. The eventual 114 is about as many as was ever going to be possible.

I'm not sure about the carnage either. Yes, the Whirlwind was armed with four 20mm cannon, but with just 60 rounds for each, that's roughly two three second bursts. The armament was not as reliable as the pilots would have hoped either.

Much as I like the Whirlwind and think it got a raw deal I think the whole Merlin powered version was a dead end. There is just too much that needed to be changed. The heck with the landing gear attachment points needing to be changed, how about whole new landing gear to deal with the weight of the Merlins, the bigger props, the bigger radiators/oil coolers ? How about needing bigger fuel tanks for the larger engines?
By the time it all got sorted out and ready to be built it would have been 1942.

As for the 20mm guns, at least they were upright and not laid on their sides like the early Spitfires in the BoB
How much trouble did the Beaufighters (first 400) have with their drum fed Hispanos?

I would note that ALL the 109s in the BoB had 60 round drums.

 

[stona]

I would note that ALL the 109s in the BoB had 60 round drums.

And two MG 17s with 1,000 rounds per gun. At a RoF of about 17/sec (firing through the propeller) that's about a minute of continuous fire. Two machine guns isn't much, even by the standards of 1940, but it's a lot better than being effectively unarmed!

Those with cannon in the wings were usually loaded with 55 rounds per gun, those with machine guns in the wings with 500 rounds per gun.

Cheers

Steve

 

[Dimlee]

Since ammo supply was short, was it possible to fire not all 4 cannons at once but 2 and 2 separately, from different buttons/triggers? Just to conserve the ammunition. Probably it could be field modified?

 

[stona]

Various armament combinations were suggested for the Whirlwind, but the four drum fed cannon arrangement that went into production did not have any kind of selector switch.

Rate and weight of fire were considered vital to the chances of shooting down an enemy in the fleeting time expected to be available. All four cannons fired simultaneously (when they worked). The cannons were fired by a single button on the spade grip of the control column.

The cannons, cocked on the ground, were fired hydraulically (up to P6969) and pneumatically on all subsequent aircraft. A field modification would probably have been beyond the squadron capability and would have required approval at a higher level anyway.

Cheers

Steve

 

[MIflyer]

On the P-38 there were a separate buttons on the wheel for the cannon and the machine guns. The radio PTT transmit was via a "Horn Button" in the middle of the wheel. The drop tank release was somewhere under the seat or other hard to reach place. None of this was satisfactory. You never wanted to just fire either the cannon or machine guns; you always wanted both at the same time. Taking a hand off the wheel or throttles to key the radio was not acceptable, either. And fumbling around for the drop tank jettison when you got bounced was not popular.

At least one outfit ganged the cannon and machine guns together on one button, used the former cannon button for the PTT and used the horn button for the drop tank release. Of course, for a while, until they got used to it, some pilots were calling the tower and dropping their tanks instead.

The T-30 throat mike could use a switch that hung around the pilot's neck, but again that required taking your hand off the controls.

 

[Shortround6]

Various armament combinations were suggested for the Whirlwind, but the four drum fed cannon arrangement that went into production did not have any kind of selector switch.

Rate and weight of fire were considered vital to the chances of shooting down an enemy in the fleeting time expected to be available. All four cannons fired simultaneously (when they worked). The cannons were fired by a single button on the spade grip of the control column.

The cannons, cocked on the ground, were fired hydraulically (up to P6969) and pneumatically on all subsequent aircraft. A field modification would probably have been beyond the squadron capability and would have required approval at a higher level anyway.

Cheers

Steve

It made sense, with the quantity of aircraft built, to not waste time/engineering effort in trying to make retrofit changes to the Whirlwind. However, had production continued, there were a number of easy fixes/improvements that could have been incorporated.