Rated altitude was at 15000 ft. There it was supposed to make 885 HP, RPM being 3000 and boost of +6.75 psi*.My understanding is that the peregrine had a relatively low critical altitude, top speed is given at 15,000 ft on the Wiki, though of course I don't know if that is accurate.
I don't think that the Whirlwind had featherable props, either, nor did any British made aircraft of that era other than the Manchester.
Even at that the Whirlwind pilots were more willing to fly home from France with one turnin' and one burnin' than were the Typhoon pilots with a misbehaving engine. I'd guess that the ditching characteristics of the Whirlwind were better than the Typhoon; they hardly could have been any worse.
More evidence that even in 1941 it was quite hard for a twin to top a P-38.
Well I don't think it was enough power at altitude for an aircraft of that weight. Spitfires and Bf 109s had higher than 25,000' ceiling and were still performing pretty well at that altitude. Because of the nature of the BoB a lot of the fighting was done at that altitude.
12Y may have been "hopeless" but on the <6,000 lb D.520 it was able to confer a 10,000 meter ceiling
You are assuming the intake system (supercharger, carb, ducting, valves, etc) on the Peregrine has capacity to increase boost at more less same efficiency. However, if limitations in system e.g. max airflow through carb has been reached, preventing additional airflow, the increased boost might simply be heating mixture. From what I see in charts, Peregrine gained ~80hp from 5 psi (max cruise) to 6.75psi (max power); Given you're only increasing 2.25 psi, getting 1k hp isn't exactly easy-peasy. Definitely worthy of betting a pint over.Rated altitude was at 15000 ft. There it was supposed to make 885 HP, RPM being 3000 and boost of +6.75 psi*.
* Wikipedia is wrong here wrt. boost: Power output: 885 hp (660 kW) at 3,000 rpm, +9 psi boost
At +9psi, we'd get easy-peasy 1000 HP from a Peregrine (but at perhaps 10000-12000 ft, not at 15000).
tl;dr: rated altitude of the RR Peregrine was just fine for 1940.
Lower wing loading/better airfoil of Spitfire means it does have same altitude limitations as Whirlwind. Spitfire Mk.1 has ~34.5k' service ceiling (with Rotol CS prop)Didn’t the Whirlwind have same altitude limitations that the Spitfire Mk 1 had ?
The extra 5k' (30.3k' vs 25k' service ceiling) for Rotol over DH is less altitude limited, but still not in Spitfire league.And don't forget that the one prototype with the Dowty props was not altitude limited in the way the DH prop aircraft were.
In 1940, the P-36 was still a serious adversary - the French Curtiss 75C-1 accounted for a majority of victories over the Luftwaffe.
I've read on the internet that Whirlwind have had two engines, meaning that available power at 15000 ft was 1770 HP. Even the He 113 was worse there.
How much the high wing loading was to blame the Whirly dishing it out at 25000 ft?
What was the percentage of LW bomber sorties flown at 25000 ft?
Where have I stated that D.520 have had a hopeless engine?
The P-36 had a ceiling of 32,000+ feet - not sure how much higher one would need to go, considering BoB's average combat height was 15,000 feet.The P-36 / Hawk 75 was indeed a serious adversary, but in France it did most of it's fighting over the battlefield where most of the bombers were flying low. Same for Finland. There is a big difference between a close air support role and the fighter cover for that, vs. strategic (and terror) bombing of the type going on in the BoB. Russian fighters also had fairly poor high altitude performance but they didn't need it.
Over England though, the fighters needed to be able to fly high.
Different Theaters, different environments, different requirements.