spitfire v mustang mpg

[Simpo Two]

I think Mustangs were already hitting compressibility issues/tactical Mach with the power they had. More would just have created problems and pilots killing themselves.

[Eric Mc]

That's it, essentially. By the time the notion might have occured to North American, they were already designing their first jet fighter, the J-1 Fury.



However, before it even flew NA had been made aware of the swept wing technology being devleoped in Germany and subtantially revised the Fury into the F-86 Sabre

[Zad]

To continue the theme, here's a photo of a Corvette! Not a V8 though.

[Penguinracer]

I've always had a soft spot for the Griffon powered Spitfires. Yes, they weren't around for the B of B, the Griffon sounds rougher than the Merlin (different firing order so as to reduce harmonic issues), were somewhat less agile than the early Spitties, & were rarer - but they seem to me to be the love child of a P51D & a Mk IX Spittie! I think four Griffon powered P51s were raced at Reno, Precious Metal being one of the four still extant. WorldJet & I think (I may be wrong) Red Baron were Griffon powered.

[Eric Mc]

The Griffon Spits evolved partly in parallel with the Merlin variants.

The first Griffon version was the Mk XII, which was essentially a re-engined Mk II.

The main operational Griffon Spits were the Mk XIV (and its photo recce cousin, the PR.XIX) and the Mk21/22. The latter entered service after WW2 by which time the future was obviously going to be jet powered.

Not that it stopped Supermarine persevering with the Spiteful and Seafang.

Edited by Eric Mc on Thursday 3rd June 14:04

Edited by Eric Mc on Thursday 3rd June 14:05

[FourWheelDrift]

Precious Metal looks like a Shackleton conversion as it has contra props as well.

http://www.warbirdaeropress.com/articles/PMmods/PM...

[Penguinracer]

But you gotta love the 'Bear!" Now with Rod Lewis's considerable resources behind it ol' 77 is due for a come back! Yes, I believe that the Whittington's picked-up four Shackleton Griffons which ran with different (smaller?) superchargers to Spitfire XIV versions. The post-war transport spec Griffons (57s) were considered to be more durable than those fitted to Spitfires (61, 65 & 72) during the war. Just as the Wright R-3350s from DC-7s were higher spec engines using better metals than those used on B-29s during the last part of the War. I apologise for digressing from the OP.

[Firestorm]

To be fair, you'd have to assume that the two aircraft were being flown by pilots of equal skill and experience. The two models that it is most fair to compare would be the Spitfire XIV and P-51D, which were the primary models in service with their respective services in mid-1944. The Spitfire XIV actually entered service in January 1944, five months before the P-51D.

The Spitfire XIV was faster than the Mustang, more maneuverable, had a higher service ceiling, could climb better, and even had a better rate of roll, which was formerly the Mustang's only performance advantage over the Spitfire. It was superior to the P-51D in EVERY combat category except initial dive speed and range, and the only way range came into play in a dogfight is if the P-51 could fly around long enough for the Spit to run out of fuel!

Some quotes:

William Dunn (US fighter ace who flew Spitfires, P-51s, Hurricanes, and P-47s): "Now, if I had to make the choice of one fighter aircraft above all the others - one that I'd rather have tied to the seat of my pants in any tactical situation - it would be, without any doubt, the world's greatest propeller driven flying machine - the magnificent and immortal Spitfire."

Eric Brown (RN test pilot and holder of the world record for number of types of aircraft flown): "I have flown both for many hours, and would choose the Spitfire [over the Mustang] if given a choice in a fight to the death."

Writer Jerry Scutts, quoting German pilots in his book JG 54: "The Jagflieger had to keep a wary eye out for enemy fighters, particularly Spitfires, a type JG 54's pilots had developed a particular aversion to...Pilot reflections do not, surprisingly enough, reflect over-much respect for the Mustang or Lightning, both of which the Germans reckoned their Fockes were equal to - unless they were met in substantial numbers."

Gordon Levitt, Israeli fighter pilot, comparing the Spitfire, Mustang, and Avia S-199 (Jumo-engined Bf 109), all of which the Israelis flew: "Despite the pros and cons, the Spitfire was everyone's first choice."

Karl Stein, Luftwaffe Fw 190 pilot (who served mainly on the Eastern front): "English and American aircraft appeared on the scene in those closing days of the European war. Spitfires were the most feared, then Mustangs..."

USAAF 31st FG War Diary (when transferring from Spitfires to P-51s): "Although pilots think that the P-51 is the best American fighter, they think the Spitfire VIII is the best fighter in the air."

USAAF pilot Charles McCorkle (who flew both in combat), reporting on a mock combat between a Spitfire and Mustang in 1944: "Now we could see which was the better aircraft...a Mustang and a Spit took off for a scheduled 'combat', flown by two top young flight commanders. When the fighters returned, the pilots had to agree that the Spitfire had won the joust. The Spit could easily outclimb, outaccelerate, and outmaneuver its opponent..."

The Mustang was a great fighter, but it was great because it had the range the Spitfire lacked, enabling it to take the fight to the enemy.

But in a one-on-one dogfight, there's absolutely no comparison. The Spitfire would win decisively, 99 times out of 100...

[dr_gn]

Firestorm said:

Eric Brown (RN test pilot and holder of the world record for number of types of aircraft flown): "I have flown both for many hours, and would choose the Spitfire [over the Mustang] if given a choice in a fight to the death."

Perhaps a more relevant quote from Eric Brown is

"If I was in a dogfight, I'd prefer to be in a Spitfire. The problem was I wouldn't like to be in a dogfight near Berlin, because I could never get home to Britain in a Spitfire..."

The Mustang laminar flow smooth wing stuff is a bit of a red herring. After all the likes of Airbus and Boeing are still grappling with the issues of designing and building a true laminar flow wing today. For a start the prop wash and gun ports would put paid to any laminar flow for the majority of the span, and a few squashed flies or dents would see to the rest. Any significant drag reduction from the wing design came from the section rather than smoothness. The laminar flow section has its thickest section further back than normal. You can see it quite clearly if you look at a Mustang and, say, an early Spitfire side by side.

The Mustang was simply a very well designed and built aircraft, particularly the radiator duct design.

[Eric Mc]

dr_gn said:

The Mustang was simply a very well designed and built aircraft, particularly the radiator duct design.

Which was very, very clever.

One of the designers who worked on the radiator system, Dale Myers, went on to play a key roll in the design of the Apollo Command and Service Modules - and also worked in key rolls at NASA.

[telecat]

The Spitfire could and indeed did gain a Tank behind the Pilot which increased the range to that of a P-51. Joseph Smith did include the larger tank in the MK XVIII. This was after He and Jeffrey Quill had a MK IX modified with a 75 Gallon Tank behind the Cockpit. A 45 Gallon Drop tank was also added for the flight. The flight was from Salisbury Plan to the Moray Firth and back again, all below 1,000ft. In distance, and not taking into account the various diversions for weather and terrain, it was the equivalent to flying from East Anglia to Berlin and back and took five hours. It did make the Spitfire Unstable when the tank was full but it appears the P-51 also had a similar problem which in both cases had the same solution. Burn the fuel in the rear tank down until the Centre of Gravity was restored. Then use the Drop tank.

[Avipatable]

[quote=Eric Mc]The Mustang had a much more advanced wing than the Spitfire. The US was very advanced when it came to undrstanding airflow around wing sections and had come up with the principle of Laminar Flow - which was applied to the Mustang.

I have read that R.J. Mitchel was aware of laminar flow but chose not to use it due to its fragile nature and stall and climb characteristics... I just can't remember where, perhaps McKinstry's book.

Perhaps it is all compromise... the Spit with its normal aerofoil could climb well but had less range; the Mustang could fly far but with less climb ability. I think its fair though, as many have pointed out, that the Mustang is a later and cleaner design, but also with a far larger internal fuel capacity.

It would be great to have some "mpg" or equivalent for equal speeds.

[Simpo Two]

Avipatable said:

I have read that R.J. Mitchel was aware of laminar flow but chose not to use it due to its fragile nature and stall and climb characteristics... I just can't remember where, perhaps McKinstry's book.

I seem to recall that a laminar flow wing had to be very smooth to work properly - perhaps Mitchell thought he had enough on his hands building the (very complex at the time) airframe of the Spitfire without adding even more complexities?

[dr_gn]

Simpo Two said:

Avipatable said:

I have read that R.J. Mitchel was aware of laminar flow but chose not to use it due to its fragile nature and stall and climb characteristics... I just can't remember where, perhaps McKinstry's book.

I seem to recall that a laminar flow wing had to be very smooth to work properly - perhaps Mitchell thought he had enough on his hands building the (very complex at the time) airframe of the Spitfire without adding even more complexities?

Laminar flow wings in this context just have a section that's different to 'non-laminar flow' wings, not some magical production method that gives impossibly smooth surfaces.

Edited by dr_gn on Tuesday 14th October 23:11

[Simpo Two]

Just to make sure I didn't imagine it - a quick google. First hit:

'The P-51 Mustang was the first aircraft intentionally designed to use laminar flow airfoils. However, wartime NACA research data shows that Mustangs were not manufactured with a sufficient degree of surface quality to maintain much laminar flow on the wing. The RAF found that the Bell P-63, despite being designed with laminar airfoils, also was not manufactured with sufficient surface quality to have much laminar flow.'

http://www.aviation-history.com/theory/lam-flow.ht...

[dr_gn]

Simpo Two said:

Just to make sure I didn't imagine it - a quick google. First hit:

'The P-51 Mustang was the first aircraft intentionally designed to use laminar flow airfoils. However, wartime NACA research data shows that Mustangs were not manufactured with a sufficient degree of surface quality to maintain much laminar flow on the wing. The RAF found that the Bell P-63, despite being designed with laminar airfoils, also was not manufactured with sufficient surface quality to have much laminar flow.'

http://www.aviation-history.com/theory/lam-flow.ht...

yes, section not smoothness defines the so called laminar flow wing, thats what I wrote...The B24 had one, as did the later Hawker Tempests, all built with pretty much identical methods to a Spitfire wing- nothing particularly special about production. ETA The section itself gives lower drag by delaying flow separation at the expense of harsher stall characteristics.

Edited by dr_gn on Wednesday 15th October 13:58

[hidetheelephants]

FourWheelDrift said:

tank slapper said:

Although aerodynamics probably made a difference, fuel capacity was a bigger factor. A Mk XIV Spitfire could carry about 500 litres internally, while the P-51D could carry 1000 litres and close on another 1000 litres in drop tanks.

Although smaller internally Spitfires also carried external tanks, from the VB mark they were designed to use "slipper" drop tank of 30, 90 or 170 gal capacity plus others were modified to carry the same tanks as used on the Mustang.

On my mobile to pain to search for images clear enough to show but this computer image shows it clearly, on the centreline between the undercarriage.

I recall reading in Jeffrey Quill's Spitfire that the slipper tanks could be used as drop tanks, but they 'flew' rather too well and tended to hit the airframe after being released! They were also definitely not stressed for combat!

[AER]

dr_gn said:

Simpo Two said:

Just to make sure I didn't imagine it - a quick google. First hit:

'The P-51 Mustang was the first aircraft intentionally designed to use laminar flow airfoils. However, wartime NACA research data shows that Mustangs were not manufactured with a sufficient degree of surface quality to maintain much laminar flow on the wing. The RAF found that the Bell P-63, despite being designed with laminar airfoils, also was not manufactured with sufficient surface quality to have much laminar flow.'

http://www.aviation-history.com/theory/lam-flow.ht...

yes, section not smoothness defines the so called laminar flow wing, thats what I wrote...The B24 had one, as did the later Hawker Tempests, all built with pretty much identical methods to a Spitfire wing- nothing particularly special about production. ETA The section itself gives lower drag by delaying flow separation at the expense of harsher stall characteristics.

The fact is, it's pointless to select a laminar flow section and make it out of a riveted aluminium construction because the wobbly skins lose you all the advantages you thought you had, but leave you with all the downsides. On the other hand, it might have been a reasonable choice for the Mosquito with its cold-moulded style construction. In reality, it actually did have a foil with a delayed thickness, but not so much that it could be termed laminar flow.

Edited by AER on Wednesday 15th October 07:04

[jamieduff1981]

dr_gn said:

Simpo Two said:

Just to make sure I didn't imagine it - a quick google. First hit:

'The P-51 Mustang was the first aircraft intentionally designed to use laminar flow airfoils. However, wartime NACA research data shows that Mustangs were not manufactured with a sufficient degree of surface quality to maintain much laminar flow on the wing. The RAF found that the Bell P-63, despite being designed with laminar airfoils, also was not manufactured with sufficient surface quality to have much laminar flow.'

http://www.aviation-history.com/theory/lam-flow.ht...

yes, section not smoothness defines the so called laminar flow wing, thats what I wrote...The B24 had one, as did the later Hawker Tempests, all built with pretty much identical methods to a Spitfire wing- nothing particularly special about production. ETA The section itself gives lower drag by delaying flow separation at the expense of harsher stall characteristics.

Edited by dr_gn on Tuesday 14th October 23:54

Edited by dr_gn on Tuesday 14th October 23:58

Mark Hanna seemed to attribute a great deal of the Spitfire's manouverability and general handling capability to its impeccable stall characteristics. He described that the Spitfire began to buffet fairly early as the angle of attack increased and implied a very predictable and linear sounding build up towards a full stall. I remember him saying one would need to be "crass" to lose control of a Spitfire.

Such characteristics would indeed allow a fairly average pilot to extract close to maximum turn performance from the aircraft, unlike a Mustang which could bite if mishandled. Probably not dangerous to widow-maker degrees unless at very low altitude where Mustangs didn't choose to spend their time, but possibly enough to lose the edge over a Spitfire in combat.

[dr_gn]

AER said:

dr_gn said:

Simpo Two said:

Just to make sure I didn't imagine it - a quick google. First hit:

'The P-51 Mustang was the first aircraft intentionally designed to use laminar flow airfoils. However, wartime NACA research data shows that Mustangs were not manufactured with a sufficient degree of surface quality to maintain much laminar flow on the wing. The RAF found that the Bell P-63, despite being designed with laminar airfoils, also was not manufactured with sufficient surface quality to have much laminar flow.'

http://www.aviation-history.com/theory/lam-flow.ht...

yes, section not smoothness defines the so called laminar flow wing, thats what I wrote...The B24 had one, as did the later Hawker Tempests, all built with pretty much identical methods to a Spitfire wing- nothing particularly special about production. ETA The section itself gives lower drag by delaying flow separation at the expense of harsher stall characteristics.

The fact is, it's pointless to select a laminar flow section and make it out of a riveted aluminium construction because the wobbly skins lose you all the advantages you thought you had, but leave you with all the downsides. On the other hand, it might have been a reasonable choice for the Mosquito with its cold-moulded style construction. In reality, it actually did have a foil with a delayed thickness, but not so much that it could be termed laminar flow.

Edited by AER on Wednesday 15th October 07:04

It's clearly not pointless: Why did NAA keep it on the Mustang if it gave no benefit AND gave the aircraft compromised handling? Why would Hawker and Supermarine subsequently select it for the later versions of the Tempest and Spitfire? Neither had particularly different skin smoothnesses form previous versions, definitely nowhere near that required for true laminar flow. Plus the gun ports and prop wash etc. produce turbulent flow for the vast majority of the wing surface. A gun port (or any other discontinuity from a tiny squashed fly upwards) produces a triangle of turbulent air streaming back over the wing.

As I said, the section itself gives lower drag without needing a perfectly smooth surface finish. Even today no aircraft in volume production has a true laminar flow wing through surface finish alone.