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Sea Furies only win when the P-51s are not entered. Streg and Voodoo are much faster although Rare Bear was just as fast. That being said I wouldn't use Reno as an example. The aircraft are far, far removed from practicality.Just look at Reno Unlimited`s, thats been won by annular air cooled (effectively no different to a water cooled annular) and belly scoop systems (p51),
and planes like Sea Fury`s which have both leading edge and annular cooling systems at once.
Here's a fact in the report that should not be overlooked:
"With an annular radiator the power plant weight is 180 lb. heavier than with the underslung type,..."
That is a big difference and would have an effect on performance, negating some of the drag benefits and reducing rate of climb. It is also moved the c of g forward 2 1/4 in which might require counter balancing (think P-39 nose armor.....or maybe not). Note that the chin radiator is already well forward on the Tempest, for the Hornet moving the radiator from the leading edge to the front of the engine would result in a much greater c of g shift.
Standing tall amongst pygmies. The underslung radiator was not an exemplar of good aerodynamic design. It was a holdover from the Typhoon adopted as an expedient to get the Tempest into production ASAP. The Mark I Tempest was much faster and climbed quicker according to this website:Here it is said that the Tempest with annular radiator at least appears to be better at the climb than its counterpart with underslung radiator, but concrete climb times haven't been recorded.
Rolls Royce didn't think their powerplant installation was any different from a leading edge radiator in terms of drag. From "The Merlin in Perspective" by Alec Harvey-Bailey
"The same Mosquito was subsequently fitted with Rolls-Royce powerplants with chin radiators. Tests before and after conversion using the same Merlin 23 engines and propellers showed no measurable difference in performance at the same all up weight. On calibration test flights the speed was 378 mph true at 18,000 ft at a weight of 18,400 lb."
If it truly did 452, which I doubt, it would be faster than the Tempest. That Sabre IV must have pumped out 4000 hp to move the brick like Typhoon that quickly The disruption to production had to be less than for the Tempest which also had a new forward fuselage plus a new wing. It would seem to be a no brainer to modify the engine bearers rather than build a new wing.Something a bit confusing for me here, wiki says that an annular radiator was tried on the Typhoon, so the same thing on a Tempest is covering old ground "
One Typhoon, R8694, was used by Napier for trials with the more powerful Sabre IV, cooled using an annular radiator and driving a four-bladed propeller. The new engine and radiator arrangement required substantial modifications to the forward fuselage and engine bearer structures. Although a maximum speed of 452 mph (727 km/h) was claimed by Napier, it was decided that the modifications would not be worthwhile, mainly because of the promising development of the Tempest, and because the disruption to Typhoon production would not be sufficiently outweighed by any benefit achieved.[79][80]"
I think Napier were the UKs version of Bell, a lot of fanciful BHP and speed figures. The new wing and fuselage were for the Tempest which was really a better Typhoon, as I understand it the Typhoon for ground attack was good enough so they just wanted as many as possible. They werent made in the same factory.If it truly did 452 which I doubt, it would be faster than the Tempest. That Sabre IV must have pumped out 4000 hp to get the brick like Typhoon that quick. The disruption to production had to be less than the new wing and lover fuselage for the Tempest.w
In my notes I have the Typhoon R8694 fitted with a Sabre VI engine and the annular radiator with cooling fan.
I have never been able to find any authoritative data on the power curve for this setup.
View attachment 674235
re annular radiator tests on the Tempest
Apparently there were several variants of annular radiator tested.
View attachment 674237
ww2aircraft thread at "Hawker Tempest V production batches"
The Fairy Firefly went from a chin radiator to a rather protruding leading edge system. I wonder if there any performance comparison between the two installations was ever done.Curses, my photo of the comparison graph is so blurry I cant see a damn thing.
However, it DID say that the main problem with the leading-edge radiator installation for this prototype Napier fighter was that the required radiator size combined
with the very thin wing desired, meant that putting in the leading edge radiator meant compromising the profile, as a "Bump" would be needed. So it may well be that
as with most proposals, some things work well in some planes, and less well in others.
View attachment 674198
According to the report posted by spicmart the Tempest I had to locate everything forward of the front spar which was less than ideal. The Firefly installation is well forward of the front spar but appears to have much more space.Exactly what is a leading edge system?
Inlets, radiator matrix and outlet/s all have to be forward of the forward wing spar?
Inlets and radiator matrix have to be forward of the wing spar, with outlet/s behind the forward spar?
Inlets have to be forward of the wing spar, with and radiator matrix outlet/s behind the forward spar?
If you are trying to cram all three in front of the spar and exit the cooling air above or below the the spar it seems like the turn may be fairly tight?
Obviously you have less frontal area than a chin radiator but the speed changes in the airflow may not be as good as as a good ventral radiator.
A lot depends on the airflow through the ducts in addition to the size of the frontal area?
First of all what is it cooling? The Mosquito Hornet had everything in the wing leading edge, while the leading edge set up quoted by Napier was for a P&W R2800 so that can only be for oil and any intercooler ancilaries?Exactly what is a leading edge system?
Inlets, radiator matrix and outlet/s all have to be forward of the forward wing spar?
Inlets and radiator matrix have to be forward of the wing spar, with outlet/s behind the forward spar?
Inlets have to be forward of the wing spar, with and radiator matrix outlet/s behind the forward spar?
If you are trying to cram all three in front of the spar and exit the cooling air above or below the the spar it seems like the turn may be fairly tight?
Obviously you have less frontal area than a chin radiator but the speed changes in the airflow may not be as good as as a good ventral radiator.
A lot depends on the airflow through the ducts in addition to the size of the frontal area?
The leading edge set up was for a Tempest I.First of all what is it cooling? The Mosquito Hornet had everything in the wing leading edge, while the leading edge set up quoted by Napier was for a P&W R2800 so that can only be for oil and any intercooler ancilaries?
In the article posted by Spicmart post #26 the engine is a P&W R2800The leading edge set up was for a Tempest I.
View attachment 674405
No its not. The table in the flight article is the same table I excerpted rom the original report. Nowhere in the Flight article does it state that the drag data is for the PW 2800. In fact the table does include the drag data for the Centaurus Tempest. The R-2800 is only mentioned towards the end of the article in a weight comparison.In the article posted by Spicmart post #26 the engine is a P&W R2800
Is that based on test results?The sliding ring cowl configuration does not add drag unlike the ones with hinged, articulated gills, including the leading edge system with its single flap outlet.