Well anyway, I just wanted to say regarding this thread, I'm glad someone revived it because I really enjoyed reading the whole thing. Thanks to everyone who posted in it thus far, it has been both an entertaining and informative read. I was waiting to really chime in on the major themes until I'd read through the whole thing, and I finally have.
So here is my two cents, FWIW:
First to restate the obvious, of course this is a "what-if" -we know what really happened, they didn't continue the design. Ultimately it doesn't matter what we think, they did what they did. This is just for fun and as a thought experiment. I know sometimes we all get kind of invested in this or that aircraft design on an emotional level. We all do it. We all have our favorites and our little underdogs we root for, it's not rational but it's part of the fun of being into WW2 aviation, right? And of course we have our national biases, but we should try to keep in mind that just because we are familiar with the rationalizations of why our own nation made this or that decision, doesn't mean we necessarily should buy into it.
All that said, I think Shortround6 is right about the Lysander. And the Defiant too. At least the Lysander (1,786 built) and the Defiant (1,064 built) still had a combat role, however limited or marginal, before being relegated to target tug duties. Others like the Henley (202 built) never did and designs like the Battle (2,200 built) and the Blackburn Botha (580 built) and Roc (136 built) should have been retired right away as soon as it was apparent how hopeless they were. The British were not alone in this by any mean. In the US, we had aircraft like the dreaded Brewster SB2A Buccaneer (with 771 built), and of absolutely no use to any air force anywhere, and the Curtiss SO3C Seamew (795 built), which had to be quickly withdrawn from service... just to mention two obvious cases. We also had quite a few marginal types which didn't do much good and even killed a lot of good pilots but I don't want to get into side arguments so I'll leave them unnamed.
The point being that the Western Allies in general and the British specifically definitely had some aircraft in production that they had no reason to built. In fact those which ever even saw action were probably costing lives of those unlucky enough to get sent into combat in them.
Which makes a
proven design like the Whirlwind a shame to have to shut down with such a short production run. I do understand the issue with the engine.
Personally, were I to show up in the halls power in England circa 1939, I wouldn't advocate a radical redesign of the Whirlwind, like to put Merlins in it or something. I would say stop the Lysander production line right now, transfer the contract to the Whirlwind and make a few minor tweaks for a Mk 1 variant. Now built 500 or 1,000 more of those ASAP. If necessary for manpower, money or any other resources please immediately stop production of the Defiant and the Botha and get Blackburn and Boulton Paul to help make Whirlwinds (if that is even possible).
The Whirlwind was a small plane, that is why it was so fast. It's too small for Merlin engines. It works well with the wings it has, so leave them be. Some people think a small plane is a problem, and I'm not sure if it was entirely apparent in 1938 or 39, but small planes were
faster, all things being equal. The Spitfire was small and the even zippier Bf 109 was smaller still. Sure they both had short range but the need for improved versions of both types continued to the very end of the war. Especially in the era before 1,500+ hp engines, smaller was just
better for a fighter in many ways. So in my opinion the Peregrine engine, far from being a dead end, was a really good idea. I don't know how rare it was or if other nations had equivalent designs, but to me it's a stroke of genius. A smaller engine that can power that 1940 era bird to 360 mph is something special. Especially since we know with a little work they got have gotten it much faster still. I bet if it had been developed for another year or two the Whirlwind could well have become a 400 mph airplane.
Designing a new fighter is
always a roll of the dice. You never knew when a new design was going to pan out or if it ever would. Shortround6 pointed out the long painful saga of the Typhoon. The US had similar teething problems with the P-38, with the failed P-46 and P-60 and so forth. The Germans had the Me 210 and He 177 and so on. That is why a proven design that clearly only needed a little fine-tuning really shouldn't have been abandoned so lightly.
I basically agree with Shortround6 that a relatively 'lite' refit was all that was needed to make the Mk 1 version a fully viable combat aircraft. Cross feed the two fuel systems and plumb for external tanks, convert armament to 3 x 20mm with belt feed and more ammunition, improve radiators, put in bigger tyres, maybe replace the hydraulics if it's not too radical of a change, and generally tweak anything that was breaking on a routine basis. And bingo, you had a fighter which could do things few others available to Britan in 1940 could:
- It was a proven design capable of flying combat missions, with all the major design flaws worked out. It only needed some fine tuning.
- Pilots liked it. Same could not be said for the Typhoon or say, the P-39 (outside of Russia).
- It could top 360 mph, that is fast enough to contend with Bf 109s. It's kind of the red line for a good fighter in 1940-41. Anything over 350 mph is in the mix for Western fighters.
- In spite of being a twin, it was apparently quite agile.
- Though it was only a low altitude design (at least initially) there was a need for good low altitude fighters!
- It was versatile and looks like a good fighter, a good short range recon plane, and a good CAS / precision bomber.
- Apparently it could fly reasonably well on one engine. Not all two engined warplanes could do that.
- It was the most heavily armed operational Allied fighter of it's day, certainly in it's (over 350 mph) performance class.
- The Whirlwind could apparently tangle with Bf 109s and survive. How many fighters anywhere in the world in 1940 could do that? It's a fairly short list.
- I think it would have been a good Fw 190 killer.
- There was a long period where those capabilities remained in high demand. Not until the Spit IX was available was the 190 threat faced down. All that time Whirlwinds could have been shooting them down, flying with the Spit Vs as backup.
- It could dive-bomb at a steep angle and manage the pull out - with no dive brakes. While not unique that is not a common trait in WW2 aircraft.
- Apparently it could carry two 500 lb bombs which was a heavy bomb load for a fast fighter bomber in 1940 - 41.
- It was a good enough design that the 1.0 version was still able to fly successful combat missions 3 years later. Without any real improvements that I'm aware of.
- It clearly had room for further development. External fuel tanks and a little more internal gas, a few tweaks to engine cooling systems and exhaust, and you already have a much more capable airplane. From there the sky is the limit (especially if they ever developed a 2 speed peregrine)
All in all, it was clearly an unusually good design that already was past the hardest phases of the design cycle. It was in that happy place where you can start to fine tune the basic design and get things out of it you never realized were possible initially (like I bet, 380 or even 400 mph for the Whirlwind) and make all kinds of interesting and useful variants to do other things beyond the original design specs. It had many traits not found in other Anglo-American fighters for years to come and had the versatily to do several useful tasks pretty well.
Finally subjectively, I am of the (not always reliable) school that a good fighter airplane should look beautiful: have sexy lines,
appear to be fast and sleek and elegant. The Whirlwind checks all those boxes for me (in exactly the way the Skua doesn't). I know it's unscientific but the Whirlwind is a damn nice looking fighter. I made a model of it to compare with my other fighters of the early to mid-war, and it stands out for its elegance. That is a small racehorse but it's definitely a throroughbred.
Obviously the big problem was the engine. Sure Rolls Royce wanted to concentrate on their best design the Merlin, and other promising designs to come like the Griffin, but I also think the Peregrine (and the Kestrel) was a good idea in and of itself. The Peregrine seems to have been cancelled due to problems with the Vulture (made up of sticking peregrines together). Nobody seems to have been considering it for it's own merits. Small planes seemed like they were on their way out in 1940 probably because the military people and the company people knew there was a need for more of everything: more bombs, more fuel, more guns, more armor etc.
But how many planes got bloated too quickly, loaded down with too much weight and declined in usefulness as a result. The P-40 is a good earlyish example of that, sure I love it as a design but all that weight had a way of degrading the fighter. Only by stripping them down and overboosting to that elusive ~ 1400 - 1500 hp level did they get it to perform as needed to cope with the best Axis fighters. Another good example is the B-26 Marauder. The earlier Glenn Martin designs - 167 and 187, were sleek and fast, relatively small and light. More and more and more stuff got stuffed into the B-26 and they ended up making a "widow maker" that took a long time to make into a safe, good performing aircraft. It did some useful duty but it never lived up to the hopes of the design (and in my opinion, was never as good as the much simpler and smaller Baltimore). Some other designs ultimately worked out in spite of being too huge and heavy - the P-47 with it's massive engine and turbo could muscle through all that extra drag.
And yet meanwhile the small 32' wingspan Bf 109 kept being improved and kept pace with all the Anglo-American designs to the end of the war*. And the small Russian planes kept pace with the 109s. Turns out you don't need 3,000 horsepower to go 420 mph - you can also do it with a smaller cleaner body and short low-drag wings. To me that underlines the message: smaller is better, at least to some extent.
Of course small has it's downside too. The Whirlwind was never going to be a long range fighter or fighter-bomber.. Eventually you'd have the mosquito for the latter and the P-38 and later still P-51 for the former. But until that point, I think the Whirlwind could have been useful, a Mk I or Mk Ia version, nothing requiring a major investment. Just make about 500 more and I bet it would have helped, and that would have been enough to push for a Mk II.
Mk II or III is where you could talk about making more drastic changes like to the wing or a different engine. But I think they should have stuck with the Peregrine!
S
* we can argue which was better - Spit, P-51, P-47, Fw or 109, but we can probably all agree the 109 remained in contention for the top spot until the very end.
P.S. the Wiki says the No. 263 squadron had "considerable success" vs. Ju 88s, Do 217a, Bf 109s and Fw 190s. Does anyone have more data on that? The Wiki on 263 sqn doesn't mention any dogfights with 109s or Fw 190s, only one possible ju 88 kill. There is also a 6 August 1942 raid where the Wiki claims Whirlwinds shot down 3 x Bf 109s for no losses. Anybody look into that yet?
I don't know if Whirlwinds got any victories during the channel dash fight or not. The fact that all four aircraft made it back to base in spite of apparently fairly heavy damage to three of them actually speaks quite well of the design to me. This is in general one of the advantages of a twin-engined fighter but twin engined fighters also needed to be fast to survive. The Beaufighter was great in the maritime role and as an intruder etc., but it wasn't quite fast enough to be a day time fighter over land. Neither was the Me 110 ultimately. But the Whirlwind was.