I don't understand how some planes ended up being so fast

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The importance of top speed and rate of climb in addition to the obvious, is that they are indicators of an aircraft's potential.
The faster plane will have more options.

top speed is done flying straight and level. As soon as you begin to bank the speed falls off. Deflection of the control surfaces cause drag, flying with wings tilted/banked causes drag as in the loss of lift has to be countered by an increase in the angle of attack of the wing.
Take two planes, one that can do 330mph and one that can do 360mph at the same height. The 2nd plane can actually be performing gentile maneuvers at 330mph, wide turn or gentile climb as opposed to just flying straight and level.

Even if you are at 300mph the faster plane still has more options because it has more surplus power to accelerate with, or climb or compensate for a steeper bank angle/tighter turn.

Nobody had enough power to compensate for a 5-6 G turn for very long even if the pilot didn't black out, without loosing altitude.

The "faster" plane may not be using it's "speed" at all times but you can bet the pilot (if he is any good) is using the extra power that speed margin represents.
 



Actually, the 13' 1" paddle blade prop was adopted by the Corsair early in -1D production, and retrofit to earlier aircraft as available, meaning the Avenger, Corsair and Hellcat all wound up with the same prop. Climb and low speed acceleration was slightly improved (If my memory isn't sabotaged). My buddy Bruce (he has the 11th from the last FG-1D with some factory F2G mods) had some brand new bat-handle blades (13' 4") and briefly considered backdating the plane but traded them away for more relevant parts.

(He also had a short tailwheel strut.)
 
On the topic of exhaust thrust, if you want to see an extreme example of the power of it, go to youtube and look up Jeff Diehl header break. These engines are now putting out over 11,000 HP out of an 8.4 Litre engine and I have been told that it takes roughly 1,000 HP to drive the supercharger alone!
 

Thats actually pretty efficent iirc a RR Merlin 60 series engine producing 1600hp was taking around 400hp to drive the supercharger.
 

Actually what you may be seeing is the exhaust gas collecting under the car vs venting out the side. It wouldn't take more than a few pounds per sq in of pressure under that body to lift the car off the ground. I am guessing that is what blew the hood off.
Interesting that the car swung to the left, opposite the intact right side headers, Exhaust thrust from those pipes may have been what shoved the car to the left?

I would note that these racers don't seem to be using much of the exhaust thrust for propulsion. With the upcurve in the end of the pipes they may be using the "thrust" to help keep the car on the ground?

I know I could practically clean street gutters with the exhaust from one of the fire trucks I drove.

Exhaust thrust is both simple and complicated. It is mass time velocity, that is simple. Getting it pointed in the direction you want it, keeping it stream lined, and not using a long convoluted pipe that allows it to both cool (reduces pressure/velocity) and slow down due to friction in the pipe and turbulence in the bends is more difficult, keeping up the velocity of the exhaust stream while sending it through a turbine, collecting it and redirecting it through a rear facing outlet is a lot harder.
 

The Bearcat is another good example. Considering its size, its extremely smooth outer surface, and considerably high amount of power, you'd think it would be much faster than any version of the P-47 or Corsair, but that just wasn't the case...
 
The Bearcat is another good example. Considering its size, its extremely smooth outer surface, and considerably high amount of power, you'd think it would be much faster than any version of the P-47 or Corsair, but that just wasn't the case...

You can only go so fast using a prop. 500 MPH and you're up against the wall for speed; hence the move to the jet engine.
 
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you have to compare speeds at the same altitudes, The Bearcat used a single stage supercharger so it's 2000 plus horsepower tended to disappear pretty quick.

A clean F8F-1 using military power of 2100hp was good for 331knots (380.9mph) at sea level while a P-47D using water injection and 2210hp was good for 289.3 knots (333mph) at sea level.
F8F-1 was almost 50mph faster while using just over 100hp less.

P-47D could hit 435mph at 31,000ft where the engine was making 2220hp thanks to the turbo. The F8F-1 engine was good for just 1700hp at 16,000ft and had dropped over 30% (down to around 1200hp?) from that so by the time it got to 31,000 where it's speed was around 400mph? (405 at 30,000ft).

Corsair used a two stage supercharger so while not as good as the P-47 in had hundreds more horsepower at some altitudes compared to the F8F-1.
 


People here are doing a lot of jumping though hoops to prove your false premise. No combat jug would do 500 plus and the corsairs did not do high 400, not in any models that saw significant production anyway in WWII. At any lower altitudes the huge amount of air that a Jug had to push out of the way slowed it. Same with the corsair to a lessor degree. The Mustang's smaller air frame, narrow nose and laminar flow and low drag far outweighed having less HP.

Why wouldn't you google before posting the question?

F4U Corsair - WW2 US Navy Fighter Plane - History, Specs, Pictures

Republic P-47 Thunderbolt - The Seven Ton Milk Jug, WW2 Fighter Plane

The mustang was faster but it wasn't just about raw top speed because the jug would only fly it's top speed at very high altitude and both it and the corsair climbed like a school bus compared to the mustang. The Mustang had usable speed at every altitude. The mustang would fly an astounding 388 miles per hour at sea lever, 50 mph faster than a Jug. The jug's fastest speeds were at 38 to 40 thousand feet. That's not where dogfights happen. Loaded bomber didn't cruise or bomb anywhere near that high, more like 20 to 25 thousand feet so there is no practical advantage to the jug's 40 thousand foot speed.

dogfights happened at the bomber altitude on down. That's where the huge difference in lower altitude speed of the mustang was a huge advantage. If a jug ends up with a German on his tail at 25 thousand feet and he can't out-turn him or out fly him but he can shove the stick forward and get a gap in a dive. He better get a big one though because if it's an FW190 that sticks close enough the FW will reel in the Jug. The mustang will motor away. Reverse the situation at mid to low altitude and make the mustang the pursuer he's going to close the gap on anything in the sky. Think about a 50 mph advantage on the deck. Say the mustang is chase from a mile behind. He's gaining about 50 or 60 feet per second. Or flipped around from low to mid altitude, where most fur balls end up the mustang will run away from anything he can't out turn.


P-51 Mustang Performance
P-47 Performance Tests
 
"Carboncrank, posted:The Mustang's smaller air frame, narrow nose and laminar flow and low drag far outweighed having less HP.

Laminar Flow was never accomplished on the Pony.

Why wouldn't you google before posting the question?

I'm wondering why you haven't used google.

The mustang was faster but it wasn't just about raw top speed because the jug would only fly it's top speed at very high altitude and both it and the corsair climbed like a school bus compared to the mustang. The Mustang had usable speed at every altitude. The mustang would fly an astounding 388 miles per hour at sea lever, 50 mph faster than a Jug. The jug's fastest speeds were at 38 to 40 thousand feet. That's not where dogfights happen. Loaded bomber didn't cruise or bomb anywhere near that high, more like 20 to 25 thousand feet so there is no practical advantage to the jug's 40 thousand foot speed.

The Jug's top speed was approx. 32,000 ft on the D's 435 mph, M's - 473 mph (granted only 100 made), N's - 457 mph. As you can see it's not at 38-40,000 ft. Alt. is energy, energy is what you need to effectively fight in any aircraft; whether from high power, sleek design or Altitude. Better yet is to have all three in one aircraft.

dogfights happened at the bomber altitude on down. That's where the huge difference in lower altitude speed of the mustang was a huge advantage. If a jug ends up with a German on his tail at 25 thousand feet and he can't out-turn him or out fly him but he can shove the stick forward and get a gap in a dive. He better get a big one though because if it's an FW190 that sticks close enough the FW will reel in the Jug. The mustang will motor away. Reverse the situation at mid to low altitude and make the mustang the pursuer he's going to close the gap on anything in the sky. Think about a 50 mph advantage on the deck. Say the mustang is chase from a mile behind. He's gaining about 50 or 60 feet per second. Or flipped around from low to mid altitude, where most fur balls end up the mustang will run away from anything he can't out turn.

At 25,000 ft the FW 190 is struggling. The Jug will out turn it at 250 mph and out run it level speed at that alt. Even at 10,000 ft as long as the Jug's speed is over 250 it can out turn the 190; at least that's what the flight test against each other says.

The Mustang was a jack of all trades. It did all things good, but the only one excellent was range. That is what made the Mustang very good for the job that was required of it.

Oh and forgot to mention. The 109 had one of the least aerodynamically clean airframes of that time period for fighter aircraft. Of the different marks the F model was as clean as it would get; although the G-10 and K models were close.
 
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The other side of the coin is why some planes don't get faster, for example the P-38 only improved from 400 -> 420mph, from a power increase of 2 x 1150 -> 2 x 1600hp!

The 1937 Ki-15 3 seat fixed landing gear recon plane is interesting that it got to 300mph from a 750hp radial and a 2400km range, must be close to best performance/$hp, and did set world endurance records back in its time!

 
A couple of points?
First, Power Available vs Power Required are the two major factors, along with comparative W/L, which determine Climb and Turn Performance.

With respect to Power Required for Climb, the dominant Drag 'adds' over level flight are a.) Cooling Drag and b.) Pressure/Form Drag due both to high Angle of Attack CL, and incremental Drag of the airframe components immersed in the Prop Vortex.

For Power Available, in addition to the THP of the engine/prop combo, the Mustang also had a decided advantage in Exhaust thrust

Relative to comments made earlier about the 'inescapability' of a P-47D from an FW 190A-7 or -8 above 25000 feet? The THp of the FW 190 was declining rapidly above 20,000 feet while the P-47 (and P-51B/C) were steady from 24000 through 29000 feet. The W/L of all three were about the same with combat tanks gone and some internal fuel consumed before combat engaged. The advantage in climb and turn was pronounced for both the P-47 and P-51B/C, over the FW 190A, at bomber altitudes and above.
 
The Hellcat had a much better view over the nose and probably better to the rear, there may have been a price considered worth paying in top speed for this. The Corsair could be landed on a carrier but was not so simple.
 

you very obviously didn't look at the source material a gave. Show me where you get you "facts" otherwise it's just opinion. And I figured you go for numbers on models made in small numbers late in the war that are totally irrelevant.

The fact I errored in the top speed altitude of the Thunderbolt doesn't negate the point. The Mustang and the Jug are about same speed at that altitude, but still, dog fighting doesn't happen at that altitude. The lower you go the more glaring the speed difference between the 2 planes. So if at any point from see level up to 25k if you find yourself in a position where you need to accelerate away you are better of in a Mustang. With the exception of diving from high altitude, anything the Jug could do in air to air a Mustang could do better. Jugs became train killers while the Mustangs dominated the Luftwaffe.

I wasn't comparing the Jug to an FW190, I was comparing it to a Mustang proving the Mustang was a better air plane in every aspect of dog-fighting.

The mustang was obviously the best fighter of the war in all regards. It showed up in theater way later than the jugs and shot down a low-side estimate of 4,950 aircraft at a loss of 2500 while the jug shot down 3,662 and lost 3500. The only P47 squadrons that didn't replaced by the mustangs were the ones kept for short range ground attack missions, which it was very good at.

The air war was decided in the spring of 44. "Big Week" operations with their massive deep penetration raids drew large numbers of German planes up to fight where they lost veteran combat pilots they could not replace. Through Feb and March the Jugs still far outnumbered the mustangs in raw numbers of planes in the big missions yet the mustangs the kill per sortie numbers for the Mustangs was multiples of the Jug, possibly because the Mustangs flew far into Germany where the Germans put up their best efforts to stop the bombers. Air superiority was achieved in about 8 weeks with near domination by June 44 or there would have been no D-day. Keep in mind also that the "Big Week" Mustangs were B models.

We went from a near halt of Missions into Germany in October 43 for lack of long range support (the inadequacy of the P*47) to domination by June 44. Simply put, no P-51, no "big week". No "Big week" no June D-Day invasion,

And don't sound like the range problem wasn't a major flaw. After the disastrous long range missions to Schweinfurt–Regensburg August 17, 1943 and second Schweinfurt October 14th the 8th severely scaled back the bombing for 5 months because of the inadequacies of the P-47, waiting for enough P-51s to replace them.

Here is a daily from Dec 1st 1943 91st bombgroup 322nd squadron mission to bomb the chemical works of I. G. FarbenIndustrie A/C.(Bayer), Leverkusen, Germany. That's just 40 miles into Germany. They put 8 bombers up.
------------
Time: Take Off 0755. Target 1202. Return 1434.
Bomb Load 8 x 500 G.P, 20 x 100 I.lB.'s
Bombing Altitude 26,000
Results: Unobserved 9/10 cloud

Fighter Opposition: 40-50 E/A mostly FW190's and Me-109's with a few
Me-100's and FW-189's. FW-190's were painted to look like out P-47's.
Rocket firing E/A were in evidence. Between 1140 and 1200 hours our
fighter support did not cover our formation. It was during this
period of time that our group suffered its losses (5 A/C M.I.A.) also
4 A/C landing elsewhere in England .

Remarks: The following A/C failed to return: A/C 794 piloted by Lt.
L. J. Anderson, A/C 511 piloted by Lt. J. T. Wennenberg, A/C 836
piloted by Lt. Charles L. Early. Major H. W. Weitzenfeld, C.O. of
the 401st, was group leader.
--------------

Notice the missed hand off between P-47 squadrons. 5 of the 8 bombers were shot down in that 20 minute screw up.

Aircraft #511 was "Wheel n' Deal". The bombardier was 2nd Lt John W Temple, the husband of my mother's older sister. He spent 18 months in various POW camps.

40 miles into Germany, 160 miles from the coast, 240 miles from England and yet the Jugs had to fly in relays to cover even that, and the result was a missed relay, 5 B-17's shot down, 50 men killed or captured. My uncle's plane was hit by FW190's before the bomb run. It also had an 88 round go up through the plane right behind the pilots a out the top without exploding. The Jugs finally arrived but only covered a few minutes before they had to go home because of the range problem. The force had no fighter escort for the bomb run but "Wheel n' Deal's" didn't make to the run because it was hit again in an engine in a FW190 pass, became a straggler and a sitting duck. Still they didn't go down and they found cloud cover but as soon as they came out of the cloud the 88's were all over them one round leaving a whole in a wing "big enough to drop a cow through". They bailed out, the pilot left it on auto pilot when he left an she flew on another 10 miles or more before belly landing, still on auto pilot, on the Rhine river. The German's fished it out but my uncle had destroyed the bombsite. 9 of the ten survived.

This kind of story repeats itself over and over again until the arrival of the Mustang.

So don't try to make the P-47 into something it was not, Read the 91st dailies, see the losses.

The story of "Wheel N Deal", including it's final fight, is told here. If you don't want to read the whole page do a page search on "Wheel N Deal". BTW that page tells the story of "Memphis Belle" too as it was 91st bombgoup, 324th squadron.

Chapter 4 - One Came Home. The Stories of Those Left Behind



you very obviously didn't look at the source material a gave. Show me where you get you "facts" otherwise it's just opinion. And I figured you go for numbers on models made in small numbers late in the war that are totally irrelevant.

The fact I errored in the top speed altitude of the Thunderbolt doesn't negate the point. The Mustang and the Jug are about same speed at that altitude, but still, dog fighting doesn't happen at that altitude. The lower you go the more glaring the speed difference between the 2 planes. So if at any point from see level up to 25k if you find yourself in a position where you need to accelerate away you are better of in a Mustang. With the exception of diving from high altitude, anything the Jug could do in air to air a Mustang could do better. Jugs became train killers while the Mustangs dominated the Luftwaffe.

I wasn't comparing the Jug to an FW190, I was comparing it to a Mustang proving the Mustang was a better air plane in every aspect of dog-fighting.

The mustang was obviously the best fighter of the war in all regards. It showed up in theater way later than the jugs and shot down a low-side estimate of 4,950 aircraft at a loss of 2500 while the jug shot down 3,662 and lost 3500. The only P47 squadrons that didn't replaced by the mustangs were the ones kept for short range ground attack missions, which it was very good at.

The air war was decided in the spring of 44. "Big Week" operations with their massive deep penetration raids drew large numbers of German planes up to fight where they lost veteran combat pilots they could not replace. Through Feb and March the Jugs still far outnumbered the mustangs in raw numbers of planes in the big missions yet the mustangs the kill per sortie numbers for the Mustangs was multiples of the Jug, possibly because the Mustangs flew far into Germany where the Germans put up their best efforts to stop the bombers. Air superiority was achieved in about 8 weeks with near domination by June 44 or there would have been no D-day. Keep in mind also that the "Big Week" Mustangs were B models.

We went from a near halt of Missions into Germany in October 43 for lack of long range support (the inadequacy of the P*47) to domination by June 44. Simply put, no P-51, no "big week". No "Big week" no June D-Day invasion,

And don't sound like the range problem wasn't a major flaw. After the disastrous long range missions to Schweinfurt–Regensburg August 17, 1943 and second Schweinfurt October 14th the 8th severely scaled back the bombing for 5 months because of the inadequacies of the P-47, waiting for enough P-51s to replace them.

Here is a daily from Dec 1st 1943 91st bombgroup 322nd squadron mission to bomb the chemical works of I. G. FarbenIndustrie A/C.(Bayer), Leverkusen, Germany. That's just 40 miles into Germany. They put 8 bombers up.
------------
Time: Take Off 0755. Target 1202. Return 1434.
Bomb Load 8 x 500 G.P, 20 x 100 I.lB.'s
Bombing Altitude 26,000
Results: Unobserved 9/10 cloud

Fighter Opposition: 40-50 E/A mostly FW190's and Me-109's with a few
Me-100's and FW-189's. FW-190's were painted to look like out P-47's.
Rocket firing E/A were in evidence. Between 1140 and 1200 hours our
fighter support did not cover our formation. It was during this
period of time that our group suffered its losses (5 A/C M.I.A.) also
4 A/C landing elsewhere in England .

Remarks: The following A/C failed to return: A/C 794 piloted by Lt.
L. J. Anderson, A/C 511 piloted by Lt. J. T. Wennenberg, A/C 836
piloted by Lt. Charles L. Early. Major H. W. Weitzenfeld, C.O. of
the 401st, was group leader.
--------------

Notice the missed hand off between P-47 squadrons. 5 of the 8 bombers were shot down in that 20 minute screw up.

Aircraft #511 was "Wheel n' Deal". The bombardier was 2nd Lt John W Temple, the husband of my mother's older sister. He spent 18 months in various POW camps.

40 miles into Germany, 160 miles from the coast, 240 miles from England and yet the Jugs had to fly in relays to cover even that, and the result was a missed relay, 5 B-17's shot down, 50 men killed or captured. My uncle's plane was hit by FW190's before the bomb run. It also had an 88 round go up through the plane right behind the pilots a out the top without exploding. The Jugs finally arrived but only covered a few minutes before they had to go home because of the range problem. The force had no fighter escort for the bomb run but "Wheel n' Deal's" didn't make to the run because it was hit again in an engine in a FW190 pass, became a straggler and a sitting duck. Still they didn't go down and they found cloud cover but as soon as they came out of the cloud the 88's were all over them one round leaving a whole in a wing "big enough to drop a cow through". They bailed out, the pilot left it on auto pilot when he left an she flew on another 10 miles or more before belly landing, still on auto pilot, on the Rhine river. The German's fished it out but my uncle had destroyed the bombsite. 9 of the ten survived.

This kind of story repeats itself over and over again until the arrival of the Mustang.

So don't try to make the P-47 into something it was not, Read the 91st dailies, see the losses.

The story of "Wheel N Deal", including it's final fight, is told here. If you don't want to read the whole page do a page search on "Wheel N Deal". BTW that page tells the story of "Memphis Belle" too as it was 91st bombgoup, 324th squadron.

Chapter 4 - One Came Home. The Stories of Those Left Behind
 
The mustang was obviously the best fighter of the war in all regards.
It quite obviously wasn't. It was no match for anything at altitude from 1939 to 1943. It was no match for a Griffon engined Spitfire or an Me 262 when they came in to service. What it did have was good performance at all altitudes, fantastic range and huge numbers. Those numbers were magnified by the use of P 47s P 38s and Spitfires. After D Day when combats were at lower altitude it was no match for a Tempest in performance nor a P 47 for firepower and durability.

Mistakes made in the early days of the bombing offensive were not the fault of the machines involved. It was a learning experience for the group and required many more re con planes and weather reports to solve.
 
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I would be rather leery of using operational mistakes/mishaps in evaluating performance of aircraft.
A missed rendezvous can happen to any aircraft unless it can be shown that due to excessive head winds or some other factor that a particular aircraft could not over come that another one could.

I would also note that while the P-51 was a much superior escort fighter the P-47 was constantly evolving. Jan 1944 seeing the start of the equipping of the P-47 planes already in theater with under wing tanks in addition to the under fuselage tanks to extend range.
The under fuselage tank itself under going a series of changes and the 150 gal, under fuselage tank was introduced in Feb 1944 just in time for "Big week". it added 15 minutes of flying time (over the 108 gallon tank?) and extended radius to 350 miles.
Big week escorts were mostly P-47s.
May of 1944 starts to see the P-47D-25 show up with another 65 gallons of internal fuel which really extends the radius, even though most are being sent to the 9th Air Force. And most in theater P-47s are being transferred to the 9th Air Force as quickly as deliveries of P-51s allow.

There was a fair amount of overlap and things were happening very quickly. As of Dec 1st 1943 the Mustangs still had lots of bugs and were not yet operating with either rear fuselage tanks or under wing drop tanks. By March of 1944 all three US fighters were using under wing tanks and often larger than what what they were using in the fall of 1943 for the P-38.
Please remember that it could take several months from when a particular serial number aircraft rolled out the door of it's factory in the US and when it flew it's first combat mission in Europe.
A lot of decisions were made without the benefit of combat experience as there just wasn't time.
Fortunately they guessed correctly.
 

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