Westland Whirlwind range (1 Viewer)

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

fastmongrel

1st Sergeant
4,527
3,622
May 28, 2009
Lancashire
The Whirlwind is one of our favourite what if, coulda woulda shoulda planes but I am confused about the range of the plane. Wiki gives 800 mile range and 150 mile combat radius but I have seen other figures giving ranges down to 300 miles and flight times of as little as 45 minutes.

We know that the Whirlwind flew escort missions as far as Antwerp, anti ship dive bombing raids with 2 x 500 pounders as far as Cherbourg and Rhubarb missions with 2 x 250 pound bombs as far as the northern outskirts of Paris.

The last mission of 137 sqn on 21st June 43 was a Rhubarb to an aerodrome at Poix Du Nord, at the time wiki says 137 was based at RAF Rochford which is near Southend Essex which to me seems much too far for a Whirlwind to fly with bombs so possibly 137 was still at RAF Manston. This is still a good distance and I imagine if the radius was 150 miles the pilots were getting very nervous and keeping a good eye on the fuel gauge and mixture lever as they crossed the Channel.

I have also read that the fuel systems for each engine were seperate and if one engine died the other could not draw on the fuel. This seems very stupid and if it was so surely a modification could have been made to cross connect the tanks. Even a fuselage as tight fitting as the Whirlwind someone could have fitted a pipe and fuel c0ck somewhere.
 
We are back to the 'range vs radius' question :)

I have little doubt that a Whirlwind could fly 800 miles in a straight line at best economical speed and altitude and NO reserve. So could an Early P-47 with no drop tank.

Turing those 'ranges' into operational radius is the problem. Needed or wanting to use much higher speeds to approach and withdraw from the target area cut well into the range, Providing a useful reserve to ensure getting home (finding home field in cloud cover/rain squall) cuts the radius as does making allowance for 5-15 minutes of full power combat should it be needed.

On some planes 1 minute of full throttle was worth 4 minutes at best cruising speed.

You are right about the fuel system but I believe a few other early war aircraft may have had the same problem, they just made enough later to fix the problem. There were only 114 Whirlwinds and there was no MK II or even a Ia ;)

In hindsight they should have kept the Whirlwind and junked the Typhoon :)
 
The fuel supply system was, quote, "an Abomination", and would have been the first thing changed on any further development, which never came to pass. Never knew about not being able to transfer fuel from one engine to the other, though. That seems a tad shortsighted......
 
The official data sheet gives 570 miles at most economical speed (210 mph at 20,000 feet).

I believe ( and could well be wrong) that the data sheets have an allowance for warm-up, take-off, reserve and combat? or at least the first 2-3 with a note stating how many miles to reduce range by for every 5 minutes of combat?

Like the one for a Typhoon gives a fuel cap of 154 gallons but takes out 32 gallons for take-off and climb to 15,000ft for a "range" of 610 miles at most economical but subtract 75 miles for every 5 minutes at combat?
 
609 liters.
161 U.S. gallons.

400 liters. Me-109.
535 liters. Fw-190.
1,100 to 1,300 liters. Fw-187. 1,300 liters was projected for mass production version.
1,158 (306 gal). P-38 prior to J model.
1,270 liters. Me-110C.
1,577 liters (410 gal). P-38J.
2,420 liters. Me-210 / Me-410.

Whirlwind combat radius would probably be similar to Spitfire and Me-109.
 
I believe ( and could well be wrong) that the data sheets have an allowance for warm-up, take-off, reserve and combat?

Good point, fuel allowance for the data sheet figure is 32. It appears that with no allowance the distance becomes about 630 miles.
 
Victor Bingham's book on the Whirlwind gives it's range as --720 Miles.
a duration of 3.35hr at 215mph including 15mins take off/landing.
 
First I want to mention, I don't want to turn this thread to a FW 187 thread.

We have done a while ago (mostly delcyros) an analyse of the range of the FW 187 (B) with DB 601A1 and 1100L internal fuel.
Reference was the Bf 110 C and it's flying books.

So perhaps this examples helps to find a realistic combat radius of the Whirlwind.

Estimated performance FW 187 (B):

605 km/h at 5000m altitude at combat power (each ~1030 PS 2500 U/min, 1.30 ata).
at 1.15 ata at 5000m altitude contineous power (each 850 PS and 2200 U/min)= 560 km/h
at 0.8 ata at 5000m altitude saving performance (each 600 PS at 1600 U/min) = 480 km/h

Combat range:
- blocked residual fuel amount (varied from type to type for example Ju 88, 50 liter; Bf 110, 130 Liter) I will calculate with 50 Liter (could be more)
- engine start up, warm-up and roles: 50l (ident Flughandbuch Bf-110C)
- take off and touch-and-go reserve: 50l (ident Flughandbuch Bf-110C)
- climb to 5000m at 1.30 ata: 120l (40km distance after Flughandbuch Bf-110C)
- 30 min combat power reserve for 1.30 ata combat power: 330l (ident Flughandbuch Bf-110C)

1100l - 50l - 50l -120l - 330l = 550l
So we have 550l for combat radius:
470km (+40km climb) at 1.15 ata/ 0.89 Std
740km (+40km climb) at 0.8 ata/ 1.64 Std

in summary the combat radius will be between 255km and 390km varied from the speed.

Theoretical range:
- engine start up, warm-up,roles and take off: 75l
- climb to 5000m at 1.30 ata: 120l

1100l - 75 - 120 = 905l

= 1270km at 0.8 ata (this could be a little more because we had only the distance for 5000m climb at combat power.)

Specific consumption of the DB 601 A1 at 5000m from engine data sheets.
1.15 ata 0,22 gr/PS/h = 0,289 l/PS/h
0.8 ata 0,225 gr/PS/h = 0,296 l/PS/h

So if someone have the specific data's of the Whirwind and the RR Peregrine engine he can do a calculation.

I have my doubts about a theoritical range of the Westland Whirland of 800 miles, because this would be more then the theoretical performance of a FW 187 B with 1100l internal capacity and I don't believe that the Peregrine engines consumes so much less fuel then the early Db 601 A1 with 1100PS.

The combat radius of 150 miles seems reasonable, perhaps a little optimistic. Depends on how much combat power reserve and blocked residual fuel amount.
 
Last edited:
HP = fuel consumption, you can't make power without burning fuel, the Peregrine was a relatively small 21.2 litre engine, output was -

international rating - 860bhp @2850rpm +63/4lb boost 13500ft
Maximum 885 @ 3000rpm +63/4lb boost 15000ft
Max take off 765bhp @ 3000rpm +63/4 boost

I can't find an exact quote for combat range the 720 miles seems to be max duration not operational , but extrapolating distances from bases to targets it seems to have a radius of action of approx. 200 miles, that seems to include combat time over the target, but there seems very little data available on specifics?

Certainly an interesting aircraft, very fast low down quoted as 303mph at sea level, most of it's issues seem to revolve around politics (not including the engine being cancelled), put simply the Air Ministry didn't like Petter and Westland much, he was apparently quite the stubborn mule and didn't take kindly to people offering "advice" about his designs.
A lot of the stories about the Whirlwind seem to have originated from the upper echelons of the RAF rather than the operational people, a lot of them are hearsay and simply incorrect, and a lot of them are exaggerations, suffice to say the guys who flew and serviced them held them in high regard!

but it's removal from service can be blamed on Rolls and the air ministry who stopped making the engines and failed to develop the existing engine to produce power over 15000ft, relegating it to a low level role when the German bombers were operating higher and higher!
 
First I want to mention, I don't want to turn this thread to a FW 187 thread.

Specific consumption of the DB 601 A1 at 5000m from engine data sheets.
1.15 ata 0,22 gr/PS/h = 0,289 l/PS/h
0.8 ata 0,225 gr/PS/h = 0,296 l/PS/h

So if someone have the specific data's of the Whirwind and the RR Peregrine engine he can do a calculation.

I have my doubts about a theoritical range of the Westland Whirland of 800 miles, because this would be more then the theoretical performance of a FW 187 B with 1100l internal capacity and I don't believe that the Peregrine engines consumes so much less fuel then the early Db 601 A1 with 1100PS.

The combat radius of 150 miles seems reasonable, perhaps a little optimistic. Depends on how much combat power reserve and blocked residual fuel amount.

I appreciate the work. But comparing to the Fw 187 requires a bit more. The Whirlwind was a smaller, lighter aircraft. 5 ft less wingspan, 5 ft less length, a wing about 76-77% the size and a loaded weight "clean" of about 600lbs less than a Fw 187 with Jumo 210s.

It has less wing area and weight than a Typhoon or Tempest.

Rolls was "claiming" a fuel burn at cruise (without specifying what cruise was) of 0.48lb/hp/hr or 220grams/hp/hr.

Peregrine might viewed as a 78% early Merlin to some extent?
 
Hello SR6,

is the weight and wingspan important?

At german data sheets the specific fuel consumption is mentioned for the individual engines (Jumo 210, 211, 213 Db 601 etc...) in Liter/h or Gramm/PS/h at X ata.
I think/thought you must only know which speed the a/c will reach which X ata/specific engine and the speed depends on weight, aerodynamik (wingspan etc.) of the individual a/c.

Is this right or have I an error in reasoning?
 
Last edited:
Hello SR6,

is the weight and wingspan important?

At german data sheets the specific fuel consumption is mentioned for the individual engines (Jumo 210, 211, 213 Db 601 etc...) in Liter/h or Gramm/PS/h at X ata.
I think/thought you must only know which speed the a/c will reach which X ata/specific engine and the speed depends on weight, aerodynamik (wingspan etc.) of the individual a/c.

Is this right or have I an error in reasoning?

Your reasoning is not wrong, there seems to be little documentation of the Peregrine (at least in published sources) so it is hard to work up paper estimates.

as far as "is the weight and wingspan important?' goes, just pointing out that the Whirlwind was a smaller plane. It should have less drag although that is guess work too. The Fw 187 was very fast for it's installed power even with the Jumo engines.

Playing with the cube root rule it appears they were closer than I thought.
 

Users who are viewing this thread

Back