P-51D vs. Spitfire IX

[PAT303]

As mentioned above, the Spitfire XIV entered service more than a year before the P-51H did, months before the P-51D did and at a similar time to the P-51B.

Mustang did it's fighting beyond the range of any Spitfire with guns.

The MkXIV could take on the Me109 and FW190 with the 90G drop tank fitted so it could in fact fly as far as a P51 and still fight.

 

[rochie]

The MkXIV could take on the Me109 and FW190 with the 90G drop tank fitted so it could in fact fly as far as a P51 and still fight.

As much as i would love that to be true, it simply isn't.

from tactical trials

TACTICAL COMPARISON WITH MUSTANG III
Radius of Action
31. Without a long range tank, the Spitfire XIV has no endurance. With a 90 gallon long-range tank it has about half the range of the Mustang III fitted with 2 x 62 1/2 gallon long range tanks.
Maximum Speed
32. The maximum speed are practically identical.
Maximum Climb
33. The Spitfire XIV is very much better.
Dive
34. As for the Spitfire IX. The Mustang pulls away, but less markedly.
Turning Circle
35. The Spitfire XIV is better.
Rate of Roll
36. The advantage tends to be with the Spitfire XIV.
Conclusion
37. With the exception of endurance no conclusions can be drawn, as these two aircraft should never be enemies. The choice is a matter of taste.

 

[NevadaK]

The MkXIV could take on the Me109 and FW190 with the 90G drop tank fitted so it could in fact fly as far as a P51 and still fight.

Greetings Pat303,

There is a difference between Range and Combat Radius. Summarizing from documents over on World War II Aircraft Performance, Range is the farthest an aircraft can fly in a given configuration. In the footnotes for calculating range it is noted that when calculating range no fuel is used for warm up, taxi, take-off, and climb to altitude. The best range I can find for a Spit Mk XIV is 861 miles. Combat Radius of Action is calculated with factors for warm up, taxi, take-off, climb to altitude, and a factor for combat action (duration at WEP). Since I have the calculations for the P-51H handy, this can be demonstrated with the P-51H range being 2514 miles and combat radius for the same configuration is 1024 miles. If you want to do a simple ratio to get a rough idea of the Spitfire's combat radius we can use 40% based on P-51H numbers. The Combat radius for the Spit XIV calculates as 861 x 40% = 344 miles. My guess is that this number is a little high as the percentage of fuel used for WEP goes up with the shorter the range of the fighter.

Going back to my original post, my question really wasn't about which fighter was better, but was questioning a myth that the Spitfire was always more maneuverable or better. This came from references to the Mustang's best combat performance being at higher speeds and the energy maneuvering chart I had come across that showed the Mustang had an advantage at higher speeds. To illustrate, here is a similar chart comparing the F-18 and F-16.

and the chart from my original post with a similar shading showing the envelope where the Spit Mk IX has a definitive advantage and where the Mustang has an advantage.

Aircraft behave differently at different speeds and altitudes and while one aircraft might be "better' in one situation another might outperform it in a different situation. To me, the discussion should be a more nuanced comparison. As Rochie has stated, they are both great aircraft and should be appreciated as such.

 

[rochie]

Yep for us Brits it too easy to think the spitfire is always the most manouverable until you try and out turn an A6m at less than 200 mph !

 

[pbehn]

Greetings Pat303,

There is a difference between Range and Combat Radius. Summarizing from documents over on World War II Aircraft Performance, Range is the farthest an aircraft can fly in a given configuration. In the footnotes for calculating range it is noted that when calculating range no fuel is used for warm up, taxi, take-off, and climb to altitude. The best range I can find for a Spit Mk XIV is 861 miles. Combat Radius of Action is calculated with factors for warm up, taxi, take-off, climb to altitude, and a factor for combat action (duration at WEP). Since I have the calculations for the P-51H handy, this can be demonstrated with the P-51H range being 2514 miles and combat radius for the same configuration is 1024 miles. If you want to do a simple ratio to get a rough idea of the Spitfire's combat radius we can use 40% based on P-51H numbers. The Combat radius for the Spit XIV calculates as 861 x 40% = 344 miles. My guess is that this number is a little high as the percentage of fuel used for WEP goes up with the shorter the range of the fighter.

Going back to my original post, my question really wasn't about which fighter was better, but was questioning a myth that the Spitfire was always more maneuverable or better. This came from references to the Mustang's best combat performance being at higher speeds and the energy maneuvering chart I had come across that showed the Mustang had an advantage at higher speeds. To illustrate, here is a similar chart comparing the F-18 and F-16.

View attachment 594277

and the chart from my original post with a similar shading showing the envelope where the Spit Mk IX has a definitive advantage and where the Mustang has an advantage.

View attachment 594279

Aircraft behave differently at different speeds and altitudes and while one aircraft might be "better' in one situation another might outperform it in a different situation. To me, the discussion should be a more nuanced comparison. As Rochie has stated, they are both great aircraft and should be appreciated as such.

The thing is your argument is based on a sim chart. Where is the actual data to support the information on high g turns at low and high speed at sea level? AFAIK WW2 piston engines struggled to maintain a turn over 3 G and collecting that type of data at sea level gets people killed.

 

[NevadaK]

The thing is your argument is based on a sim chart. Where is the actual data to support the information on high g turns at low and high speed at sea level? AFAIK WW2 piston engines struggled to maintain a turn over 3 G and collecting that type of data at sea level gets people killed.

Agreed pbehn,

I acknowledged that it was a sim chart at the very start. Then again, my understanding is that many EM calculations are generated as calculations. I will do what I can to track down such information.

Regards,

Kk

 

[pbehn]

Agreed pbehn,

I acknowledged that it was a sim chart at the very start. Then again, my understanding is that many EM calculations are generated as calculations. I will do what I can to track down such information.

Regards,

Kk

There are all sorts of factors like aeroelasticity, feel and balance of controls. The Spitfire gave more notice of stall so was easier to hold near the limit, for example. At extreme speeds in a dive the Spitfire was faster but that is in "wing and propeller falling off" territory.

 

[NevadaK]

Greetings All,

Here is a link to the tactical report that Rochie cited earlier. It is a good read.

Mustang Tactical Trials

 

[GregP]

Hey Graugeist,

We could meet at a pub and drink the Battle of Britain all over again sometime with some SPitfire, Messerschmitt, Stuka, and Mustang. If we were to look, I get we could find some Typhoon and Kamakaze, too.

I would not put too much faith in an energy maneuverability diagram from a gaming website. Energy maneuverability diagrams didn't even begin to be seen until 1966 when John Boyd proposed them. By then, there weren't many, if any, WWII aircraft in regular military service and the civilians who owned the ones flying weren't usually up for beating up their engines and airframes to create documentation they didn't need for civil flying. Any energy diagrams for WWII aircraft are very likely fabricated by someone for games and very likely have little to do with real airplanes other than being vaguely in the correct shape.

Most warbird pilots can pull their fighters around pretty tightly and they can feel the beginnings of a stall nibble as well as anyone. But, I don't know any who have made a diagram for it. The guys who do air combat with lasers in Beech Mentors and SIAI-Marchetti SF.260s may have such a diagram for those airplanes, but they didn't when I looked into it many years ago (back in the 1980s).

 

[Marcel]

Damn...I forgot about this one.

Well, there we have it, folks. The ultimate Spitfire world beater.

Case closed - now on to the great debate of which was better: the P-47 or the Typhoon

A typhoon is way bigger than a single thunderbolt

 

[pbehn]

A typhoon is way bigger than a single thunderbolt

By how many gills (Imperial)?

 

[rochie]

Greetings All,

Here is a link to the tactical report that Rochie cited earlier. It is a good read.

Mustang Tactical Trials

Sorry i thought I'd linked that as well !

 

[PAT303]

As much as i would love that to be true, it simply isn't.

The Mustang can't fight with full tanks and drop tanks the MkXIV could so what I said is true to a degree. Likewise the range thing has been done to death, a Spitfire could never match a P51 but could still go a very long way with aux and drop tanks fitted.

 

[GrauGeist]

A typhoon is way bigger than a single thunderbolt

*technically* a Typhoon is a Thunderstorm.

Soooooo...

 

[pbehn]

Greetings All,

Here is a link to the tactical report that Rochie cited earlier. It is a good read.

Mustang Tactical Trials

It details the performance of a Mustang MkIII (P51C) against the Spitfire Mk IX, Mk XIV and the Tempest V which were its contemporaries. The P-51D was heavier had slightly more drag and at altitude slightly less power but it was optimised as an escort fighter.

 

[GrauGeist]

The Tempest was actually heavier than the P-51, at 9,000 pounds clean compared to the P-51 clean:
B/C at 6,985 pounds
D/K at 7,635 pounds.

 

[NevadaK]

Hi Everyone,

What was the phrase, those who forget history...here is a quote from a similar thread a while back:

Hi guys:

The Air Fighting Development Unit (AFDU) based at Wittering and Duxford was under the control of Fighter Command and the Air Ministry where it conducted comparative trials and developed and promulgated tactics effective against the enemy. Jeffrey Quill, Chief Test Pilot for Supermarine, wrote that the "Air Fighting Development Unit represented Fighter Command and […]did a most useful job in relating the various British fighters to those of the enemy and in developing tactics on behalf of the command."

The author of Comparative Performance of Fighter Aircraft, Sqdn. Ldr. T.S. Wade, D.F.C, A.F.C, R.A.F.V.R., had served as O.C. Flying at the AFDU. Those charts appear to be a product of AFDU evaluations.

The relevant portions from Wade's article relating to this thread's current direction are summarized below:

[…]What follows is intended to give the average non-technically minded reader some idea of how some of these aircraft compare with each other in the matter of performance and manoeuvrability.​

​

Comparison does not mean obtaining results from an indiscriminate dogfight between two fighter types, but a practical assessment of the information gained as a result of specific tests in specific circumstances. These circumstances are standardized by dividing the tests up into two categories, namely, Factual Comparison, which includes speed, rate of climb, range, endurance and acceleration, readily measured against the stop watch, and Competitive Comparison, such as turning circles, rates or roll and dive zoom climbs. Rates of roll, of course be measured either way. The choice is a matter of opinion.​

​

Turning Circles​

​

In circumstances where the ability to turn quickly or tightly are infinitely variable, and where two aircraft are nearly the same, such as the Tempest V and Thunderbolt II, a great deal depends on the ability of the pilots. Speed must be taken into account if the results are going to be of any real value.​

​

For example, if a Tempest dives on a Thunderbolt with an overtaking speed of only 50 mph, the Thunderbolt will easily be able to avoid the attack by turning, although at the same speed in the hands of equally competent pilots, the Tempest will outmanoeuvre the Thunderbolt. This advantage, however, is no by any means so apparent at high altitudes, due to the greater engine efficiency of the Thunderbolt above 25,000ft.​

​

Similarly, where low-altitude and high-altitude fighters are compared any advantage shown by the former will be reduced as the high-altitude fighter gets nearer to its best operational altitude. After taking all these considerations into account, the position of the aircraft relative to each other will be seen from the diagram.​

​

Once again, the Spitfire maintains top place, followed by the Mustang, Meteor, Tempest and Thunderbolt. Too much regard to this order should not be paid, particularly by the individual who will angrily recall the occasion when he out-turned a Meteor when flying his Tempest. This sort of thing is inevitable, but we can only repeat that where the circumstances are common to both aircraft, these positions are not far wrong. (my emphasis) ​

Before smearing S/L Wade with comments such as "wartime propaganda", "biased", "the chart is wrong in that all the aircraft are going in a 45 degree angle", it might be beneficial to read to read more closely what he wrote and note the context in which his conclusions were reached.

My opinion is that the article is interesting when viewed as a pilot's reflections (who happened to head up the trials) on what the comparative tests revealed.

With regards to the main thread subject of P-51 maneuverability; I have many/most of the wartime performance and comparative trials on the type which when taken together paint a fairly clear picture of the P-51's performance capabilities. I find the performance curves to most efficiently impart information such as level speed and climb. It must be said, however, that I had a completely different sense of flying the aircraft in combat and a feeling for how it performed after having read through all the Encounter Reports.

Its one thing for a Technical Report to state:

"The airplane is very maneuverable with excellent controllability at all speeds up to slightly over 400 MPH indicated, the highest speeds attained in level flight. Stability is good about all axes, and recovery from stalls is normal. The airplane has a fairly short radius of turn and an excellent rate of roll."​

That's useful and informative.

Tactical Trials further add to our understading with statements such as:

"The Mustang III is very similar to fly and land as the Mustang 1. It is therefore delightfully easy to handle. It is as easy to fly as a Spitfire IX with the exception that the rudder is needed whenever changing bank…"​

It's a whole other ballgame, however, when you read a pilot's Encounter Report such as that of Lt. Richard D. Bishop wherein he recorded:

"I'll never worry about meeting a FW 190 in a 51 since I was able to outturn, outdive and generally out-maneuver him at all altitudes, from 23,000 feet to the deck; I could follow him in anything and do a lot more besides."​

Read a couple hundred of these P-51 Encounter Reports, go ahead – set aside a few hours and do it, you won't regret the time spent - you can't help but be impressed with the P-51's capability.

Mike

from this thread: P-51D maneuvrability - what it was in reality ...

It's time for me to go find a good Mustang/Spitfire beer. Cheers.

Kk

 

[NevadaK]

Hey Graugeist,

We could meet at a pub and drink the Battle of Britain all over again sometime with some SPitfire, Messerschmitt, Stuka, and Mustang. If we were to look, I get we could find some Typhoon and Kamakaze, too.

I would not put too much faith in an energy maneuverability diagram from a gaming website. Energy maneuverability diagrams didn't even begin to be seen until 1966 when John Boyd proposed them. By then, there weren't many, if any, WWII aircraft in regular military service and the civilians who owned the ones flying weren't usually up for beating up their engines and airframes to create documentation they didn't need for civil flying. Any energy diagrams for WWII aircraft are very likely fabricated by someone for games and very likely have little to do with real airplanes other than being vaguely in the correct shape.

Most warbird pilots can pull their fighters around pretty tightly and they can feel the beginnings of a stall nibble as wella s anyone. But, I don't know any who have made a diagram for it. The guys who do air combat with lasers in Beech Mentors and SIAI-Marchetti SF.260s may have such a diagram for those airplanes, but they didn't when I looked into it many years ago (back in the 1980s).

Greetings GregP,

I get what you are saying with a gaming sim. I would be curious to know what parameters and engines they are built on. I suspect that there is more horsepower going into some of the gaming calculators than we give them credit for. I find the EM diagrams really fascinating and how they came to be used as design tools. The F-15, 16, and 18 were all designed using EM performance envelopes as design goals and had a significant impact on the evolution of the fighter jet. As a generalization, I think they can be useful and well, are good for starting a conversation. We do building design modeling that incorporates fluid dynamics and thermal modeling for fairly large complex structures on lesser systems than these gaming platforms.

Regards,

Kk

 

[Marcel]

*technically* a Typhoon is a Thunderstorm.

Soooooo...

So a thunderbolt is part of a typhoon. Hmmm, okay, as the Thunderbold have wings as well, does that make the Typhoon a biplane?

 

[GrauGeist]

So a thunderbolt is part of a typhoon. Hmmm, okay, as the Thunderbold have wings as well, does that make the Typhoon a biplane?

I don't know to be honest, but I do know that where there's Thunder, there's a P-38.

But would that be the result of a Tempest?