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davparir,
I know that the Mk.VIII with the Griffon installed was capable of around 5,100fpm.
F4U-4 375 4150 446at26k 440 2800
Fw-190D-9 385 4430 431at16k 418 2165
Spitfire XIV 389 5000 447at26k 446 3100
IIRC the top speed of the Fw 190D-9 was about 438 mph with MW50 at about 16k.
Yes, much of the data about the FW 190D-9 is testing data from FW done for aerodynamic purposes and not to ascertain top speed.
The Basic Jumo 213A was a bomber engine and ran at 1750hp on 87 octane B4 fuel. Three power raising boost systems were introduced within a few weeks of intial service entry.
1 A rich mixture system that injected fuel into the eye of the supercharger, this achieved 1900hp.
2 The Oldenberg system of MW50 water methanol injection, installed by Luftwaffe technicians. Supercharger pressure was used to pressurise the MW50 tank and blow the mixture into the inlet.
3 A more developed high flow MW50 system that pumped the mixture in, this required control system modificatcations by junkers technicians, this was the 438mph version.
4 There was also a version which combined the above with C3 (96/130) octane fuel may have seen servive on eastern front.
It should be noted that the speed of 438mph is respectable given the low altitude it was achieved at and the 87 octane fuel.
The Jumo 213A used on the Fw 190D-9 engine was a bomber engine left over from cancelled Ju 188 production. It had a single stage two speed supercharger. A proper fighter engine would have been the Jumo 213C which incorporated all of the power boostiing systems and produced 2000hp on C3 alone. It also had the mountings for an engine canon and the required propeller. Jumo 213A was interim solution. The 213C probably fell foul of high octane fuel issues.
The Fw 190D-13 had a Jumo 213F or (potentially EB engine) with a two stage 3 speed supercharger of around 2240 or 2300+ power. It also had hydraulic boosted ailerons. Speed was 458mph. A few got into service and Goetz's Yellow 12 survives in the NASM.
Of course the FW 190D series itself were also interim to the more modified long span high altitude Ta 152H and Ta 152C (which had shorter wings for more agillity)
Some versions of the D-13 were to get wing tanks for considerably greater range, where the outer 20mm guns were.
davparir,
I read the report on 44-1 fuel that you posted. It said the merlin 66 in the Mk.IX was cleared for +25 and the Mk.XIV was cleared for +21 boost. I saw the general statement."It is understood that the maximum permissible boost pressure in these engines is plus 25-lbs per sq.inch". The statement was saying that of all the engines tested safely, that +25 boost was the maximum permitted in ANY of them. Not ALL of them.
Later Griffon engines were cleared for +25 boost, but not the Griffon 61/65. At least not for combat durring WW2. It was tested extensively in hopes of catching V-1s though.
I know that the Mk.VIII with the Griffon installed was capable of around 5,100fpm. That was a prototype for the Mk.XIV. I believe the maximum climb rate of the Spit 14 at +21 is somewhere in the middle of 4,700-5,100fpm. Like I said, I have not seen figures or graph showing the climb rate of the Mk.14 at +21 boost. I would love to though.
I'm agreeing with Vincenzo on this one.
Oh, and one last thing The F4U-4's figures in clean (no pylons) are: 383mph/SL
I have wrestled with the inconsistency of the F4U-4 climb data for many years and I am still not satisfied with an answer. Flight test on the F4U run by the Navy in August '45 and March '48 on tail number identified aircraft clearly indicates that the rate of climb of the F4U at 2100 to 2250 hp is around 3700 to 3750 ft/min. The F4U-4 hp from WEP to Mil varies from 2380 to 2450 for WEP to 2250 to 2100 for Mil, a delta of between 130 to 350 hp. The P-47D, with an increase of hp from 2200 to 2600, a delta of 400 hp gives an increase in climb of 500 ft/min. Now the F4U is a noted better climber than the P-47 so it should do better. The F6F, a better climber than the F4U, shows an increase of 280 hp generates about 400 ft/min. The F4U-1 (W) was tested at 3400 ft/min ROC at 2095 hp and a 3700 ft/min at 2250 hp. That's 300 ft/min for 165 hp increase. Doubling the horsepower gain to 330 hp, the ROC would increase to only 600 ft/min ROC. The F4U-4 itself is tested at an 800 ft/min increase at a 400 hp increase. So, comparing the data with all other F4U testing, a reasonable rate for the F4U-4 at SL would be more accurately put at around 4400 ft/min. It is unreasonable that a max of 350 hp is going to increase the climb of the F4U-4 by 1000 ft/min, maybe with a 1% air vehicle and engine.AND 4,770fpm/SL.
Pylons (wing racks) have little impact on climb other than some added weight.(actually the climb rate is with the double clip wing pylons).
I'll correct my data so all your apples line up.Apple s to apples and interceptor to interceptor.
SL
P-51B (no racks) 386 mph 4430 ft/min
5k
P-51 400 4420
10k
P-51 420 3900
20k
P-51 442 3200
It is interesting to note that the P-51B/D was operationally capable of performing at these levels in May, 1944,.
davparir,
Where did the Spitfire and 190 figures come from? Can you post a graph with info? I would love to see them.
Great stuff buddy. Thanks, Jeff.
Vincenzo said:i'm not sure that P-51 was operationally at these levels from may, but a month or two more is not a large difference
But 75" was approved by AAF, and that did not mean that it was not available or that it was not used.the trouble is you use 75" boost but 8th AF used 72" boost,
I am not sure where I came up with the value for 5k. However, on looking at the climb test for the 44-1 fuel in detail, this shows actuals where test points are actually noted by *.in other 5k climb it's for lightweight 51
davparir,
Thanks for the info.
The figures I used for the F4U-4 came from www.wwiiaircraftperformance.com. I have seen it posted on other Corsair sights also. It can be viewed at that sight or you can go back to Vincenzo's post #250 on this thread and just click on F4U-4 Performance Summery. Speeds given in the foot note on page 3 titled CLEAN CONDITION show 383/S.L. and 463.76 mph/20,600 ft. This shows that pylons slowed the plane 8-12 mph. Speeds and climb can be taken off the graphs on page 4. Page 2 shows F4U-4 loading condition (2) that was used for the graphs.
And this represents a problem with comparing old performance tests. In the first one, the North American data has several unexplained apparent errors. The first one is the claim that the P-51B normal gross weight is 8460 lbs. This obviously is in error. The empty weight of the P-51B is 6988 lbs. Gun installation, pyrotechnics, and trapped fuel and oil raise the basic weight to 7325 lb. That would leave 1135 lbs for the pilot (200lbs), oil (94 lbs), and ammo (325lbs), which leave 516 lbs for fuel, or 86 gallons, which is slightly less than one wing tank (the P-51 has two). Gross weight as stated by Wagner in "American Combat Planes" is 9800 lbs (P-51C). I calculated the plane full up with 180 gallons (full wing tanks) as 9024 lbs. In no way is 8460 lbs normal gross weight. This looks like a 1000 lb error in the weight statement. A second problem is that it does not match the AAF test in the variation of the climb rate of 67" as compared to 75". This chart shows SL difference of 300 ft/min increase. The AAF test shows a 560 ft/min, almost twice as much. I think there is a problem with the NA charts, which does not identify a tail number.Vincenzo said:for the 5k climb
there is a chart for a 8460 lbs P-51B-5 that show 4520 fpm,
ones for a 9680 lbs B-15 that show 4000 fpm
ones for a 9335 lbs B-15 that show 4000 fpm
This Mustang III had a Merlin 100 engine and not the V-1650-7. I do not know the difference but I don't think you can compare the performance differences.ones for a 9260 lbs Mustang III tah show a bit less of 4000 fpm (+25" boost)
We know the AAF approved the 75". We have discussed the 8th AF requirements, 72", which were apparently taken with a wink. What about the 5th AF, 9th, the 11th AF, the 12th AF, the 14th AF, the 15th AF, 20th AF, and the FEAF? All had P-51s and apparently had the option of how much boost they would allow up to 75".on encounter reports maybe, it's also possible that a few pilots giving all boost thinked to give 75" but they were 72" alone. just for readers is same site that report the limit to 72" for the 8th AF