Westland Whirlwind revisited

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if Whirlwinds we're produced offshore, by CAC alongside their Beaufort line (shown below at Fishermen's Bend, Melbourne, Australia in 1943), for example. P&W Australia were already making the R-1830 Twin Wasp for the Beauforts.

That is the DAP factory which produced Beauforts, Beaufighters and Lincolns. CAC were on the same airfield and CAC built the Pratt R-1340 and R-1830 engines.
 
I agree. If the P-39 could run a drive shaft between the pilot's legs I don't see why an ammunition belt could be run from behind the pilot to the Whirlwind's guns in the nose.

Because you can't kink a .303 Browning belt through 90 degrees. The links can't flex nearly that far. Even if they could, that much kink is an invitation to jam, pop links free, and otherwise mess up the operation.
 
Because you can't kink a .303 Browning belt through 90 degrees. The links can't flex nearly that far. Even if they could, that much kink is an invitation to jam, pop links free, and otherwise mess up the operation.
This is what I have in mind, like the Lancaster, with belts behind the pilot, turning through 90 degrees to the quad guns.

lanc_ammo_ducts.jpg

Lancaster Mk X, MR/MP Armament


lanbullets.jpg


Or like this, a 90 degree bend from the box to the gun.

3036_102_260-browning-blackhawk.jpg


Just put the Whirlwind's ammo box behind the pilot. Something will need to be moved forward for CoG, maybe fuel or the radio?
 
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Because you can't kink a .303 Browning belt through 90 degrees. The links can't flex nearly that far. Even if they could, that much kink is an invitation to jam, pop links free, and otherwise mess up the operation.
See pictures of the mock ups. they were planning on turning the belt 90 degrees. Granted it is a mock up. it can be done, you just need a lot of room to do it.
Gun pod under a wing is a whole lot different than the front fuselage of the Whirlwind let alone a bomber fuselage. :)
 
Just put the Whirlwind's ammo box behind the pilot. Something will need to be moved forward for CoG, maybe fuel or the radio?
Why????????
If they had belt feeds they could fit about 120 rounds per gun in the forward fuselage. Most planes armed with 20mm guns had about 120-150 rounds per gun. The Mosquito only carried 150rpg so jumping through hoops to give the Whirlwind more than 120 rounds per gun seems like too much work for too little return.
 
Or like this, a 90 degree bend from the box to the gun.

View attachment 591282

Just put the Whirlwind's ammo box behind the pilot. Something will need to be moved forward for CoG, maybe fuel or the radio?
This worked because the aircraft were designed for low G-loads and for firing with right about 1G on. Imagine pulling 5G with those drooping belts and trying to fire them. That's vastly more resistance to the gun trying to pull the belt through.

On the Lanc: "Frequent checks of the ammunition ducts had to be made to ensure that correct alignment was maintained between the separate lengths of duct and between the ducts and the ammunition boxes."

Of course, the F-8 was notorious for ammo feed problems because of the complex feed pattern.
 
See pictures of the mock ups. they were planning on turning the belt 90 degrees. Granted it is a mock up. it can be done, you just need a lot of room to do it.
Gun pod under a wing is a whole lot different than the front fuselage of the Whirlwind let alone a bomber fuselage. :)
I stand corrected!

The corkscrew feed is ... uh ...
 
All in all, I like the four drum-fed cannons on the Whirlwind as is. If we're fixing anything it needs to be in service earlier, with improved HA performance and fuelling, both in endurance and with a tank transfer valve.

Adding underwing .303 pods in place of the two 250 lb. bombs might be useful, but they'll slow her down. Like the Gloster Gladiator's .303 conformal pods, or the Bell P-63 and its larger .50 cal pods. As mentioned earlier, space will need to be found in the wing to support the added armament.

640px-Gloster_Gladiator2.jpg


gunpods.jpg
 
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I like it, and a Bristol radial will free up RR to make their Merlins. From certain angles it would look like the Iman Ro.57. This person modeled one, looking sharp, IMO.

View attachment 591275

Our resident contrarians will tell us why it shouldn't, couldn't or wouldn't have happened, but a Bristol Whirlwind redesign also presents opportunities to swap in Curtiss and P&W engines if Whirlwinds we're produced offshore, by CAC alongside their Beaufort line (shown below at Fishermen's Bend, Melbourne, Australia in 1943), for example. P&W Australia were already making the R-1830 Twin Wasp for the Beauforts.

Nobody wants to talk about the absolutely bad performance such a plane would have????????

It seems I am one of the resident contrarians,
The Italian plane managed 311mph at 16,404 ft using engines that gave 840hp at 12,500ft. Other sources may differ on power/altitude.
The Fiat engine was only 46.8in in diameter with a frontal area of 11.9 sq ft. The plane carried a pair of 12.7mm machine guns.

Suggested engines seem to be.
The Perseus X ? 750hp for take-off and 880 hp at 15,500ft , 52in in diameter, frontal area 14.7 sq ft. again sources differ on diameter.
The Mercury....725hp for take-off and 840hp at 14,000ft. 51.5in diameter, frontal area 14.5 sq ft.
Taurus less said the better.
Cyclone 9? 1200hp for take-off, 1000hp at 14,000ft, 55.1in diameter and 16.6 sq ft of frontal area.
Twin Wasp? 1200hp for take-off 1050hp at 13,100ft 48.1in diameter 12.6 sq ft frontal area. around 1460lbs for the two speed single stage engine.
None of the these engines provide any exhaust thrust, at least not at this time or with existing cowlings. Not that the Peregrine in the Whirlwind got much in the way of exhaust thrust with the exhaust shrouds/manifolds it used.

Using British radials gives you a total dog of an aircraft and swapping in the American engines comes in late in the game.
The P-36 had about 22% more drag than an early P-40 all due to the radial engine (and loss of exhaust thrust?) and you guys want to hang TWO high drag radials on a small plane????
 
It seems I am one of the resident contrarians,
Not a contrarian = fantasist.

Using British radials gives you a total dog of an aircraft and swapping in the American engines comes in late in the game.
The P-36 had about 22% more drag than an early P-40 all due to the radial engine (and loss of exhaust thrust?) and you guys want to hang TWO high drag radials on a small plane????
And yet, the P-40E gained only 20mph over the P-36 ...

By late war, of course, the radials were getting thrust from the cooling air, along the lines of the famous Meredith effect.
 
Why????
You have four 20mm guns, which, in 1941 could easily have been fitted with belt feeds with double the ammo, a few ,303 guns are going to make very little difference to the target.
If fourty 20mm shells a second doesn't wreck the target then a few .303 guns isn't really going to do much.
You are also falling into the German trap, fitting guns with rather different times of flight/aiming points so if one set of guns is on target the other set is off target.
Belly gun pod also slows the plane down.
Belt fed guns might not have had the exposed recoil springs meaning less drag. Belt fed guns needed more recoil energy to operate the belt feed mechanism
 
Not a contrarian = fantasist.


And yet, the P-40E gained only 20mph over the P-36 ...

By late war, of course, the radials were getting thrust from the cooling air, along the lines of the famous Meredith effect.

Mighty slow P-40E???
P-40E was usually credited with a speed of 354mph at 15,000ft.
P-36 did 334MPH?
This is not a fair comparison as the P-40E engine made more power at higher altitude. so

at 5.000ft P-36A did 281mph using 1045hp from http://www.wwiiaircraftperformance.org/P-36/P-36A_38-180_PHQ-M-19-1180-A.pdf

at 5,000ft P-40B did 319mph using 1085hp from http://www.wwiiaircraftperformance.org/P-36/P-36A_38-180_PHQ-M-19-1180-A.pdf

Please note the P-40B could do 307mph at 5000ft using 950hp

other tests of later P-40s show low drag, like 276mph at 5300ft using 750hp (2280 rpm)
or P-40D doing 326mph at 5175ft using 1150 hp

There are a lot ot tests at Spitfire Performance that show cruising powers needed for speeds for both the P-36 and the P-40s. The P-40s always use much less power despite heavier weights.

Yes radial installations got better, in some cases much better, but that rather requires a time machine to get the radial Whirlwind to work, unless the goal is to have radial Whirlwinds in 1943/44 at which point they are really not needed.

The experimental two stage R-1830 installed in the 10th P-40 airframe by P & W is reckoned to have gotten the drag difference down to 8% (and/or made much better use of exhaust thrust than most other radials). ANd please note the R-1830 is the smallest diameter (least frontal area ) engine of the available engines, which means the others are just going to be worse.
 
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Contrarian or someone who sticks to established facts and precedents.

Fact number 1. Once the Peregrine was abandoned the Whirlwind was a dead duck. Everything else is fantasy.

As for armament. The British did develop a successful belt feed for the cannon, they just decided it wasn't worth fitting to the last of the aircraft in the production run and certainly wasn't worth fitting to those already cluttering up airfields in unserviceable states. This relates to Fact number 1.
The British had more pressing things to do in 1941 than fit a new nose and armament package to an aircraft equipping two squadrons, on a good day, when enough of them could be cleared to fly.

I really can't see the point in fitting gun pods on the outboard wings, presumably outside the propeller arcs, even if it was practical. There were enough problems with slats coming off (until they wired them shut) and wing tips failing as it was. This really is fantasy.
 
But if one takes the POD back to the original design then there are advantages to the radial option. Weight and fuel capacity for instance. No special engine. The two small radials and development to the Taurus which was fit for use over the sea IOTL if not developed to push more power out of it. BY 1944 the Taurus Whirlwind could be on 2,600 bhp. with the late heads. The engines are not going to be abandoned and can lever off excess Lysander production.
 
I agree the Whirlwind was dead without the Peregrine. The other engines are just too big for that small aircraft. It's small size was it's selling point. Nor does it need more guns. Of course we know that further development of the aircraft didn't happen so it's only a 'what if'. But if you think any speculation about it is useless why participate in the thread? It's a "what if" thread. We are just exploring the feasibility, as in, "could they have done it." So far we have established the following:
  1. The British were manufacturing at least half a dozen basically useless aircraft, some of them getting very nice engines by the way, for another year or two after the Whirlwind was combat worthy.
  2. RR was not at full capacity making Merlin's and probably did have sufficient slack capacity to make more peregrines, again for at least a year or two.
  3. Whirlwind was still being used in 1943 which is plenty of time to make an improved version.
  4. It would not have been hard to change the guns to belt fed.
I would agree the most useful improvements, aside from changing the guns to belt fed & just fixing some of the early minor design issues like adding redundancy and so on, would be improving fuel capacity as much as was reasonable. A two speed engine would also be nice but I think there was a niche for a maneuverable low / medium altitude fighter with 360 mph speed on the deck. I am certain it would have been helpful both around Malta and in the Western Desert. I suspect it would have been quite helpful in the English channel and the waters along the coast of Norway and so on.

What made the Whirlwind so good so early on, was to a large extent it's small size. So I don't see putting bigger engines on it, especially radials which would increase low altitude drag a lot. And obviously due to the size there will be some inherent limitations as to range, though I think there was room for some more gas. A two speed engine probably wasn't out of the question but would have required time, effort, money and attention from RR or some other Strategically vital firm.
 
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I think the main real reason it wasn't continued is just because they couldn't read the future. They had no way of knowing there was still a need for a good low-level fighter in 1941, 42, and 43. And no, I don't think the Allison Mustang filled that niche. Recon yes, fighter not so much.
 
I am puzzled by references to the Perseus etc. as large engines. Lighter than the Peregrine wet weight and not that much greater in frontal area with a height of 41 inches and adding in the frontal area of the radiators.
 
I agree the Whirlwind was dead without the Peregrine. The other engines are just too big for that small aircraft. It's small size was it's selling point. Nor does it need more guns. Of course we know that further development of the aircraft didn't happen so it's only a 'what if'. But if you think any speculation about it is useless why participate in the thread?

Simply providing a reality check to some of the more ridiculous suggestions.

Consider me out, I won't bother anymore.
 

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