F4U vs. P-51 essay

[Shortround6]

I am not saying the Corsair can out turn the Mustang (some test indicates it couldn't) but a P-61 could.

It has to do with wing area and the co-efficient of lift of the wing at the angle of attack being used in the turn vs the weight. weight alone or even wing loading alone won't tell the story.

Corsair had nearly the same wing loading as a Mustang since it's wing was about 33% bigger. What it didn't have was good coefficient of lift. In part, according to one test, due the spoiler strip on the right wing to cure the asymmetric stall.

 

[Dawncaster]

I don't see how the Corsair that weighs 3000+ lbs more can out turn the Mustang...that goes against the laws of physics...

I am not saying the Corsair can out turn the Mustang (some test indicates it couldn't) but a P-61 could.

It has to do with wing area and the co-efficient of lift of the wing at the angle of attack being used in the turn vs the weight. weight alone or even wing loading alone won't tell the story.

Corsair had nearly the same wing loading as a Mustang since it's wing was about 33% bigger. What it didn't have was good coefficient of lift. In part, according to one test, due the spoiler strip on the right wing to cure the asymmetric stall.

actual factors are follows

----------------------------------------------------------------------------------------

P-51H's 1G stall speed with 9540 lbs take-off weight (9500 lbs gross weight for power-off clean)

120 mph CIAS for power off clean condition, Clmax is 1.093
calculated with (9500 * 2) / (236 * 0.0023769 * 176 * 176)

111 mph CIAS for power on cruise condition, Clmax is 1.283
calculated with (9540 * 2) / (236 * 0.0023769 * 162.8 * 162.8)

105 mph CIAS for power on climb condition, Clmax is 1.434
calculated with (9540 * 2) / (236 * 0.0023769 * 154 * 154)

103 mph CIAS for power off landing condition, Clmax is 1.49
calculated with (9540 * 2) / (236 * 0.0023769 * 151.066667 * 151.066667)

98 mph CIAS for power on landing condition, Clmax is 1.646
calculated with (9540 * 2) / (236 * 0.0023769 * 143.733333 * 143.733333)

power ratings for power on stall are 36"hg 2300 rpm for cruise, 46"hg 2700 rpm for climb and 23"hg 2000 rpm for landing condition.

with military or combat power, Clmax will be higher.

----------------------------------------------------------------------------------------

F4U-4's 1G stall speed with 12500 lbs weight.

89.4 knots CIAS for power off clean condition, Clmax is 1.471
calculated with (12500 * 2) / (314 * 0.0023769 * 150.890201 * 150.890201)

84.6 knots CIAS for power on cruise condition, Clmax is 1.643
calculated with (12500 * 2) / (314 * 0.0023769 * 142.788714 * 142.788714)

77.7 knots CIAS for power off landing condition, Clmax is 1.948
calculated with (12500 * 2) / (314 * 0.0023769 * 131.142826 * 131.142826)

64.2 knots CIAS for power on landing condition, Clmax is 2.853
calculated with (12500 * 2) / (314 * 0.0023769 * 108.357393 * 108.357393)

power ratings for power on stall are only 21"hg 2100 rpm for cruise and 25"hg 2400 rpm for landing condition.

with military or combat power, Clmax will be much higher.

----------------------------------------------------------------------------------------

as you can see, similar wing loading but better maximum lift cofficient, Corsair can do a tighter turn for most speeds.

even with the 46"hg normal power rating, mustang's Clmax is bit lower than Corsair with minimum power rating which for barely maintain level flight until stall.

Mustang's wing was designed for speed and counter compressibility, It was somewhat unexpected, but as a result, got the high speed and high critical mach number, but it's not so great for tight TnB ACM situation.

In the TAIC and USN reports, Corsair out turn the Mustang.

Zeke caught the advantage or firing position with a just one turn for Mustang, Thunderbolt and Lightning at 10000 ft and 25000 ft.

but against Corsair, three and one-half turns were needed at 10000 ft, and at 30000 ft, there was only a slight margin in turn performance between Corsair and Zeke.

in addition, with combat flaps, the Corsair could stay with Zeke in turn until 150 knots, any other US aircrafts in the report could not do it.

and for other issue, there are two types of stall strips.

One is the type mentioned in the NACA report and the book, such as 'Americas Hundred Thousand'.

This caused much damage to the Clmax and the one pilot in test stated that he had difficult for it.

so it's not used for actual military service.

Second is equipped with production type Corsairs for military service condition.

it's much smaller than previous type and fitted in different position.

As you can see above sections for Corsair's Clmax and according to USN manuals and reports, it did not do much damage to Clmax.

 

[pbehn]

I don't see how the Corsair that weighs 3000+ lbs more can out turn the Mustang...that goes against the laws of physics...

Not against the laws of physics as I understand them but counter to what you would normally think.

I have no figures but in general if it has big enough wing area and strong enough wings it can turn instantaneously quicker than a Mustang. For sustained turn it needs enough surplus thrust to drag to maintain a higher rate of turn. Total weight is an important but not deciding factor. I believe a P47 could turn with a Bf109 in combat.

 

[grampi]

All good stuff!

 

[XBe02Drvr]

I don't see how the Corsair that weighs 3000+ lbs more can out turn the Mustang...that goes against the laws of physics...

1. More horsepower.
2. More lift.
3. Faster roll gets the turn established quicker.
Cheers,
Wes

 

[CORSNING]

Not against the laws of physics as I understand them but counter to what you would normally think.

I have no figures but in general if it has big enough wing area and strong enough wings it can turn instantaneously quicker than a Mustang. For sustained turn it needs enough surplus thrust to drag to maintain a higher rate of turn. Total weight is an important but not deciding factor. I believe a P47 could turn with a Bf109 in combat.

What made the P-47 so valuable and maneuverable at 25,000-35,000 ft. was its beautiful R-2800 and
the correct high altitude supercharger. At the right power levels and these altitudes it could outturn
any Bf.109. It could not perform this feat at lower levels though.

 

[drgondog]

it was just a joke.

from F4U-1 ACP - it optained range for internal wing tanks with drop tank at same time.

12039 lbs with 237 gal = 4.283 for no external stores.
12836 lbs with 361 gal = 4.197 for no external stores, 124 gal internal wing tanks
14003 lbs with 536 gal = 3.992 for 175 gal centerline drop tank, 124 gal internal wing tanks
12763 lbs with 536 gal = 4.142 for 175 gal centerline drop tank, 124 gal internal wing tanks, light weighted - ferry condition.

from F4U-1D ACP - 150 gallon drop tank mounted on the wing pylons shows a serious drop in miles per gallon.

12175 lbs with 237 gal = 4.135 for 2 x capped wing pylons.
14370 lbs with 537 gal = 3.529 for 2 x wing pylons with 2 x 150 gal drop tanks.

then theoretically maximum possible fuel configuration is....

use the F4U-1, 16334 lbs with 838 gal = 175 gal centerline drop tank and 2 x wing pylons with 2 x 150 gal drop tanks, plus 124 gal internal wing tanks. Not so fast.

Maximum Gross Weight for F4U-1 is theoretically 14,000 pounds, Empty Wt = 8980+ with WI; Basic Weight ~ 9670; Total Disposable Load ~ 4100 pounds. According to Dean's America's 100K, the highest table gross weight for F4U-1 was 13,900 with full internal 361 gallons of fuel, ammo and 175 gallon external tank. For F4U-4 the highest listed per Table gross weight at take-off was 14,700 pounds with 1000 pounds ordnance and 1x150 gallon C/L tank and full ammo.

yeah, over the 4000 lbs extra weight! You need to re-start at the published Max GW at Take Off Power per the tables - and you need to subtract Warm up, Taki/Take Off, Climb to Cruise and account for standard 30 minute loiter at the destination.

Maybe only 2300 pounds over max GW for -1, with 175. No proof that the -1 could carry more than the 361 internal and 175 external and take off safely and repeatedly.
So, re-do with realistic Max GW at TO? The F4U-1 R-2800-8W produced 100HP less of Take Off power than the R-2800-18W in the F4U-4.

It's like a 4000lbs challenge that lindberg did with his Corsair.

Ah, how much internal fuel and ammo for the Lindberg test? Sources? It seems BuNav did not see fit to revise ops procedures and raise Max GW at T.O. That said, I don't know what the Lindberg TO weight was. Do You?

Pilots will be in danger of taking off, can the pilot make it?

Lindberg make it with old crosswind technique of making a curving takeoff run!

That would certainly be a spectacle on a carrier. Would be interesting to see the stress analysis for a 'curving TO' on main gear in a Corsair on even a smooth concrete runway?

so now! Corsair airborne!



It is time to measure range.

start from 3.529 miles per gallon with 2 x wing pylons and 2 x 150 gal drop tanks.

No substantiation for capability for F4U-1 to Ferry with more than 1x175 gallon external? BTW the incremental Parasite drag for the incremental 175 gallon external tank and Rack is substantial - hindering MPG until the tanks are dropped. The induced drag for the increased CL required for level flight is also an increase to Total Drag

and adds the following:

- 2.0%(4.197 / 4.283) for 124 gal internal wing tanks.
- 4.9%(3.992 / 4.197) for 175 gal centerline drop tank.

result is 3.289 miles per gallon.

but I think the above factors will cause synergy.

so I will subtract 5% more.

then only 3.125 miles per gallon.

final result is...

3.125 * 838 = 2619 miles.

let's compare it to the Mustang's range.

from Mustang's Tactical Planning Characteristics & Performace Chart

Mustang with 569 gal = 2600 miles for long range power setting.

Which includes warm up, take off and climb to cruise at T.O Power - plus 30 minute reserve at destination. About 40 gallons of fuel you are not compensating for.

see? SEEEE?

CORSAIR WINS!

with approx 190 mph cruise speed at 1500 ft altitude.

See below for 'complexities' not already addressed

This is harsh, LOL

Interesting try. To get a realistic estimation you need Brequet's equations.

In this particular case, given Propeller efficiency as a Calculated known as function of RPM and Hp and Prop diameter and effective Power Coefficient; Specific Fuel Consumption rates as function of HP and velocity for different Drag conditions; and accounting for decreased weights as fuel is consumed are knowns for each condition (3x external tanks, then 1x external tank as two are dropped, then clean except racks but full internal fuel load) change L/D as step functions - as 'Knowns', then you could estimate the Range.

You reduced your presentation to extracting Gallons per mile for some of the external conditions, but that doesn't take into account the necessary changes to propeller efficiencies, as RPM/Hp changes as fuel is consumed, to attain optimal SFC for optimal cruise. You didn't account for the Delta Drag except to 'pull' mile per gallon estimates. You didn't account for velocity changes as Hp and, therefore, SFC changed. You didn't account for the Change to CL as weight and Velocity changed to maintain optimal SFC at constant altitude.

The Brequet Equation is proportional to L/D, which changes as the external drag items go way to reduce Parasite Drag and lower Induced Drag. It is also directly proportional to Velocity/SFC which changes along the flight path.

 

[CORSNING]

Dawncaster,
I have not done all the research yet to prove your graphs, but in
my opinion I think you did an awesome job putting them together
and posting them.
, Jeff

 

[CORSNING]

Damn Bill,
Nice information.

 

[Neil Stirling]

Posted a few years ago but worth repeating.

Americas Hundred Thousand page 600.

P51 D
Fuel 269 US gallons internal + 2 75 gallon drop tanks = Combat Radius 700miles.

Conditions:-
Warm up and take off = 5 minutes normal rated power.
Climb to 25,000ft normal rated power no distance included.
Cruise out at 25,000ft at 210. I.A.S (about 315mph)
Drop tanks.
Cruise back at 25,000ft at 210mph I.A.S
30 minutes reserve at minimum cruise.
Combat 5 minutes Wep and 15 minutes Military power.
Takes no account for decreased fuel consumption during decent.
No allowance is made for formation flight or evasive action other than 20 minutes combat.

F4U-1 Corsair (no wing tanks) I.A.W. Pilots Manual page 50 and 63

Total fuel including 154 gallon drop tank 391 gallons.

Warm up and take off 18 gallons
Climb to 25,000ft 64 gallons ( difference split between Combat climb and Ferry climb)
Combat 5 minutes wep and 15 minutes military power 91 gallons
30 minutes reserve at minimum cruise = 21 gallons

Total = 194 gallons.
391-194 = 197

197 gallons at 315mph at max cruise at 26,000ft (82 gallons per hour) 197/82 = 2.4
2.4 * 315mph = 756
756/2 = 378 miles.

F4U-1 combat radius = 378 miles.

Or in other words 54% of a P51-D.


Mustang IV Full internal fuel + 2 imp 125 gall drop tanks, 2,690 miles at 20,000ft at 253mph

http://www.wwiiaircraftperformance.org/mustang/mustang-IV-ads.jpg

Corsair IV Full internal fuel + 2 137 imp gall drop tanks, 1,562 miles at 20,000ft at 261mph

http://www.wwiiaircraftperformance.org/f4u/corsair-IV-ads.jpg


Neil.

 

[Dawncaster]

Dawncaster,
I have not done all the research yet to prove your graphs, but in
my opinion I think you did an awesome job putting them together
and posting them.
, Jeff

Thank you for appreciate!

Interesting try. To get a realistic estimation you need Brequet's equations.

In this particular case, given Propeller efficiency as a Calculated known as function of RPM and Hp and Prop diameter and effective Power Coefficient; Specific Fuel Consumption rates as function of HP and velocity for different Drag conditions; and accounting for decreased weights as fuel is consumed are knowns for each condition (3x external tanks, then 1x external tank as two are dropped, then clean except racks but full internal fuel load) change L/D as step functions - as 'Knowns', then you could estimate the Range.

You reduced your presentation to extracting Gallons per mile for some of the external conditions, but that doesn't take into account the necessary changes to propeller efficiencies, as RPM/Hp changes as fuel is consumed, to attain optimal SFC for optimal cruise. You didn't account for the Delta Drag except to 'pull' mile per gallon estimates. You didn't account for velocity changes as Hp and, therefore, SFC changed. You didn't account for the Change to CL as weight and Velocity changed to maintain optimal SFC at constant altitude.

The Brequet Equation is proportional to L/D, which changes as the external drag items go way to reduce Parasite Drag and lower Induced Drag. It is also directly proportional to Velocity/SFC which changes along the flight path.

Posted a few years ago but worth repeating.

Americas Hundred Thousand page 600.

P51 D
Fuel 269 US gallons internal + 2 75 gallon drop tanks = Combat Radius 700miles.

Conditions:-
Warm up and take off = 5 minutes normal rated power.
Climb to 25,000ft normal rated power no distance included.
Cruise out at 25,000ft at 210. I.A.S (about 315mph)
Drop tanks.
Cruise back at 25,000ft at 210mph I.A.S
30 minutes reserve at minimum cruise.
Combat 5 minutes Wep and 15 minutes Military power.
Takes no account for decreased fuel consumption during decent.
No allowance is made for formation flight or evasive action other than 20 minutes combat.

F4U-1 Corsair (no wing tanks) I.A.W. Pilots Manual page 50 and 63

Total fuel including 154 gallon drop tank 391 gallons.

Warm up and take off 18 gallons
Climb to 25,000ft 64 gallons ( difference split between Combat climb and Ferry climb)
Combat 5 minutes wep and 15 minutes military power 91 gallons
30 minutes reserve at minimum cruise = 21 gallons

Total = 194 gallons.
391-194 = 197

197 gallons at 315mph at max cruise at 26,000ft (82 gallons per hour) 197/82 = 2.4
2.4 * 315mph = 756
756/2 = 378 miles.

F4U-1 combat radius = 378 miles.

Or in other words 54% of a P51-D.


Mustang IV Full internal fuel + 2 imp 125 gall drop tanks, 2,690 miles at 20,000ft at 253mph

http://www.wwiiaircraftperformance.org/mustang/mustang-IV-ads.jpg

Corsair IV Full internal fuel + 2 137 imp gall drop tanks, 1,562 miles at 20,000ft at 261mph

http://www.wwiiaircraftperformance.org/f4u/corsair-IV-ads.jpg


Neil.

Good informations, Thank you!

It was a fun experience.

The ACP reflects the range at 1500 feet, but I did not think it could be used for combat sortie.

and also, felt something was lacking in writing.

both of you scratched that parts coolly.

it was itchy parts for me.

and I'm glad to know that the Corsair had a longer range with faster crusing speed than I expected.

according to ACP, -1 Corsair's best documented combat radius I knew was 555 miles even with two 150 gallon drop tanks.

in addition, it's altitude was just 15000 ft for vmax crusing out, and only 1500 ft for crusing back with 170 knots slow speed.

even considering condition was one drop tank was self-sealed and carried the entire distance, I always thought that Corsair's crusing performance was lacking to compared with ETO fighters which have high and fast cruise performances.

but 20000~26000 feet altitude? 400~500kph crusing speed? and yet acceptable range?

It was not so bad as I thought.

Goooooood.

Maximum Gross Weight for F4U-1 is theoretically 14,000 pounds, Empty Wt = 8980+ with WI; Basic Weight ~ 9670; Total Disposable Load ~ 4100 pounds. According to Dean's America's 100K, the highest table gross weight for F4U-1 was 13,900 with full internal 361 gallons of fuel, ammo and 175 gallon external tank. For F4U-4 the highest listed per Table gross weight at take-off was 14,700 pounds with 1000 pounds ordnance and 1x150 gallon C/L tank and full ammo

however, about take-off weight,

I have different information for it.

that F4U-1 seems the early type without pylons, so theoretically 14000 lbs was maximum take-off weight.

according world war II aircraft action reports,

even the -1 Corsairs operating on the carrier often used over 14000 lbs take-off weight.

500 lbs bomb.
1090 lbs for 150 gal drop tank.
1150 lbs for 8 x HVAR with racks.

this loadout is often used for Corsairs with carrier operation in 1945.

with 12175 lbs for F4U-1D's gross weight with two pylons.

total take-off weight is 14915 lbs.

if case of .50 cal ammunitions were not full, report stated 16500 rds .50 cal ammunitions used for 11 Corsairs, it means at least average 1500 rds .50cal ammunitions carried.

F4U-1D's full ammunition is 2400 rds, so subtract 270 lbs(weight of 900 rds of .50cal ammo).

14645 lbs, it's minimum take-off weight for this loadout.

and landbased corsairs, showed around 15000 lbs take-off weight.

2000 lbs for 2 x 1000 lbs bomb.
1220 lbs for 175 gal centerline drop tank.

this loadout is often used for land based Corsairs in 1945.

with 12175 lbs for F4U-1D's gross weight with two pylons.

total take-off weight is 15395 lbs.

if case of .50cal ammunitions was not full, assuming carried half of ammo(report stated no .50cal ammunitions used in sortie).

then subtract 360 lbs(weight of 1200 rds of .50cal ammo).

total take-off weight is now 15035 lbs.

and seems unpractical case, combat sortie without .50cal ammunitions.

but why not?

subtract 360 lbs again.

14675 lbs with no ammo, it's minimum take-off weight for this loadout.

now case of F4U-4, manual recommanded max 15800 lbs for take-off from runaway or catapulting.

there are a some pictures that might fit here, I have.

4 x 250 lbs bombs, 2 x 100 lbs bombs, 1000 lbs bomb, 1090 lbs drop tank, total 3290 lbs extra weight.

if their ammunitions and internal fuel tank were full, those F4U-4B's gross weight was approx 15700 lbs.

well, that pictures require the aircraft action reports for Korean War to prove above factors, so maybe not, but according to world war II action reports, most case, internal fuel tank was full filled before drop tank fitted for CV operation.

In addition, SAC stated F4U-4's maximum take-off weight was 16160 lbs.

Perhaps it's seems more close the theoretical maximum.

Improved performance of the F4U-4 provided better practical bomb load capacity over the F4U-1s.

but I think 1944 was the year of the Corsair with bombs.

At the time, there were many attempts to increase the F4U's bomb load capacity, and it's sometimes exceeded the existing limits, such as Lindberg's 4000 lbs bombs carrying which including a huge 2000 lbs bomb.

(Maj Haynes's Corsair of VMF-155, Kwajalein Atoll, 1944-08-27)

As a result of many attempts, after more precise limitations were found, such unpractical loadouts were rarely attempted in 1945.

especially for 2000 lbs bomb, it's only 22 times dropped in 1945 by VF type airplanes.

after long times, according to maunal, 2000 lbs bomb formally returned to the Corsair with F4U-5's centerline hardpoint. (F4U-4 had no centerline hardpoint for drop tank or bomb)

well, the limit load factor for all Corsairs even including AU-1 was 7.5G at 12000 lbs.

strength of the airframes were seems enough for all models.

and, not just by take-off power, maximum take-off weight was seems also affected by available take-off distance and hard points.

unpractical, but if the running distance or some conditions for take-off is given abnormally great, take-off weight could be higher than recommended maximum.

with the attempts in 1944, this is the source of early Corsair's bomb load capacity 'myth', I think.

 

[pbehn]

What made the P-47 so valuable and maneuverable at 25,000-35,000 ft. was its beautiful R-2800 and
the correct high altitude supercharger. At the right power levels and these altitudes it could outturn
any Bf.109. It could not perform this feat at lower levels though.

Thanks Corsning, I only used it as an example because when I first read it I didn't believe it, thinking it was pilots favouring their own plane. Then I read LW pilots confirm it and had to read up into how it could be possible. What you posted also shows it isn't a constant, a plane can be superior at one altitude and inferior at another. Having seen all the ammunition a P47 was loaded and where it was loaded I would say there was also a huge difference in turn and roll performance between one that has just reached 25,000ft and one that has been in combat used its ammunition and is about to head home.

 

[Koopernic]

What made the P-47 so valuable and maneuverable at 25,000-35,000 ft. was its beautiful R-2800 and
the correct high altitude supercharger. At the right power levels and these altitudes it could outturn
any Bf.109. It could not perform this feat at lower levels though.

"At the right power levels and these altitudes it could outturn
any Bf.109."

All this is predicated on the model of P-47 which received improvements in engine and moreso the model of Me 109. The Me 109 with the enlarged superchargers and Water Methanol Injection closed the gap considerably, maybe completely in the case of the G10 and K4. Me 109G6ASM, Me 109G-14AS, Me 109G-10 and Me 109K4 all had this feature. From the Me 109G14AS onwards they are virtually indistinguishable in performance though the K4 was fastest due to its retractable tail wheel.

Pilots were surprised by the Me 109's new turning ability when the new engines gave increased Power to Weight Ratio at altitude.

 

[CORSNING]

Thank you Neil. As always you provide the great information Sir.

PS: Do you happen to have any input on the BF.109F-4?

Your computer friend, Jeff

 

[Neil Stirling]

Dawncaster,

ps. but excuse me, if I did not read wrong british performance cards, the range in stated conditions of Mustang IV seems 2190 miles instead of 2690 miles.

Look at the bottom of the page, 2690 miles is including the rear tank.

 

[Neil Stirling]

Hi Jeff, regarding the 109F I think the higher speeds are not reduced to standard.

This is interesting Me 109 G-1 Flight Test

Basically it shows there was very little difference in performance between the 601E and 605A

Neil.

 

[Dawncaster]

Dawncaster,

ps. but excuse me, if I did not read wrong british performance cards, the range in stated conditions of Mustang IV seems 2190 miles instead of 2690 miles.

Look at the bottom of the page, 2690 miles is including the rear tank.

Oh, I found it.

Thank you!

------------------------------------------------------------------------------

And I have a question for everyone.

http://www.wwiiaircraftperformance.org/mustang/mustang-IV-ads.jpg

in performance card, Mustang IV's extra internal 71 Imp gal fuel increase the 500 miles, miles per gallons is much higher than range of the basic chart.

it seems due to extra fuel has no additional fuel consumtions which already included in basic chart.

http://www.wwiiaircraftperformance.org/f4u/corsair-IV-ads.jpg

Similarly, In addition to 2 x 137 Imp gal drop tanks, if using the centerline 142 Imp gal fuel tank for Corsair have extra 142 Imp gal, is it works great like Mustang IV's extra fuel?

loadout is somewhat supported by the action reports.

above action reports showed Corsairs with 2 x 1000 lbs bombs and a 175 gal 1220 lbs centerline drop tank.

this loadout often used for land based Corsairs.

so, in terms of take-off weight, 2 x 150 gal 1090 lbs drop tank with a 175 gal 1220 lbs centerline drop tank seems be practical loadout.

also, some USN and RNZAF Corsairs used it, in pictures three drop tanks fitted in their Corsairs.

but unlike the Mustang IV's 85 gal internal fuselage tank, 175 gal centerline drop tank is an external store which have much heavier weight and drag.

therefore, complex formula is required for calculation.

and in this part, I lack knowledge for calculation.

Excuse me, but I would really appreciate it, if someone make a cool estimate.

this is started with a my joke of the crawling Corsair, but in the above post, I'm interested by Corsair's practical high speed cruise performance which is far better than I expected.

So I want to see the maximum of it.

ps. Corsair's centerline fuel tank was 1220 lbs with 175 gal capacity in ACP, but in british maunal it has 170 gal capacity (142 Imp gal), it confuses me.

 

[swampyankee]

A lot of aircraft performance, especially with supercharging is not intuitive. US aerodynamicists were also very good.

 

[pbehn]

A lot of aircraft performance, especially with supercharging is not intuitive. US aerodynamicists were also very good.

Not only aircraft, I knew a guy who tried racing a Kawasaki 750 turbo motorcycle, complete disaster, it was a great demonstration that only useable power is important, a huge output that takes one or two seconds to arrive is almost useless and very dangerous.

 

[Shortround6]

It is very hard to compare aircraft and motorcycles. Granted an aircraft engine has massive amounts of torque but they also have that big propeller that acts like a huge flywheel. An aircraft engine, regardless of type of supercharger, is going to take a while to gain hundreds of RPM compared to a motorcycle or car ( which often used lighter flywheels for racing). Also propellers grip on the air is a lot less firm than the ground vehicles grip though it's tires.