P-51D maneuvrability - what it was in reality ...

[Rapecq]

Hi

I've been reflecting on this aspect of P-51 Mustang characteristics and I couldn't get to any reasonable conclusion. I've heard that laminar wing reduced drag, but it will also stall earlier. However, I also read that P51 could turn very sharply and was quite controlable at high speeds.

So guys I would be grateful If someone could enlighten me on P51 maneuvrability (turning, rate of roll, handling at high speeds) in comparison to German Fighters like Fw 190 A or Bf 109G-K.

Regards,

 

[FalkeEins]

..... late model Gs were capable performers and the well armed "Beule" was a easily a match for a Mustang.. in a 1 v 1 turning fight the P-51 has little chance ..it was heavier and in a tight turn the 109 could gain some height advantage, the pilot also being able to pull harder in the turn by adjusting the angle of incidence of the tailplane... easing off the throttle a little could easily bring the 109 around on the tail of the P-51..

.. Unfortunately for your average 109 pilot the P-51 was rarely encountered alone.

"...You always had to watch out for the wingmen, which many of us tended to forget. But above all the main thing was, never go into a dive with a Mustang on your tail!.."

( the above adapted from an account by a III./JG 300 pilot)

 

[Hop]

Have you read the test reports at WWII Aircraft Performance

If you look at the Mustang section, they have an AFDU (British testing unit) comparison of the Mustang III (P-51B/C) against some of its contemporaries.

 

[Brain32]

Yes that WWII Aircraft Performance site has enourmus amount of very usefull documents However please keep in mind that all those comparisons are made with captured axis planes in questionable condition and with pilots which were most certanly not as familiar with the planes of their enemy as they were with their planes

I have some Russian turn time numbers, however condition of both P51 as also the axis planes is again unknown(atleast to me)
Turns were made at 1000m
P51 - 23sec
FW190A8(3900kg) - 21-22sec
BF109G2 - 20-21,6sec

And yes P51 had very light controls at high speeds

 

[FLYBOYJ]

Don't forget - later in the war P-51 drivers had G suits....

 

[syscom3]

And above all it had speed and a good rate of climb.

Speed = energy = maneuverability

 

[Soren]

Be very careful using the WWIIaircraftperformance site as reference for German fighter performance as it has a habbit of presenting the very lowest of figures obtainable in this area - the author being known for his bias toward Allied a/c.

Nontheless it is a good source for info on allied a/c, but please draw your conclusion(s) from the originial data available and not from what someone says !

As to the P-51 maneuverability, well at low to medium speeds it was clumsy compared to the German fighters while at high speed it could compete.

 

[syscom3]

s to the P-51 maneuverability, well at low to medium speeds it was clumsy compared to the German fighters while at high speed it could compete.

You mean the German fighters could compete........... the P51 was 50 mph faster than the -109 and 30 mph than the -190.

 

[Udet]

You mean the German fighters could compete........... the P51 was 50 mph faster than the -109 and 30 mph than the -190.

Sorry syscom but this data is incorrect.

The P-51 D had a maximum speed of 703km/hr at altitude on WEP which could be utilized for a couple of minutes only. No WEP being applied and the maximum speed of the plane is of course lower than that...do you know what the maximum speeds of the 109 G-10 was?

50mph faster than the 109? Where on earth did you get that from?

You are knocking on Kufurst´s door.

 

[Kurfürst]

Hi

I've been reflecting on this aspect of P-51 Mustang characteristics and I couldn't get to any reasonable conclusion. I've heard that laminar wing reduced drag, but it will also stall earlier. However, I also read that P51 could turn very sharply and was quite controlable at high speeds.

So guys I would be grateful If someone could enlighten me on P51 maneuvrability (turning, rate of roll, handling at high speeds) in comparison to German Fighters like Fw 190 A or Bf 109G-K.

Regards,

I would say the pilot's statements on the Mustang's manouveribilty was relative to the previous 8th AAF fighter the flew, which mostly meant the P-47. The 47 was big, and was rather poor at turns with it's great weight and wignloading. The 51 was a big improvement compared to it in this regard.

In comparison to German fighters, it was fair. It was probably a match to the FW 190 in turns, and rather inferior to the 109 in turns, which is supported by Mark Hanna who flew both. In roll rate, it was completely inferior to the FW 190, and vs the 109 it was a mixed matter. The 51 had excellent roll rates at high speed, whereas the 109 was restricted in this regard, otoh the low speed rolling of the 109 was better.

Generally the controls of the 51 were light and responsive, a bit like the 190, but it's stall characteristics were not as docile as the 109s or other better behaving fighters.

In speed it was considerably faster than the FW 190A models, and about the same as the Dora-9. The 109s it again depends on model; the early 1943 G-6 models that Allied tests were performed against were of course, much slower. The high altitude 109Gs (/AS models, 109K, G-10) which begun to appear at about the same time as the Mustang were entirely comparable at all altitudes, ie. doing around 690-710 km/h max speed at around 7500 meters, same as the Mustang. Most 40-50 mph accounts are based on British tests with Mustang vs. '109G' and 'FW 190A', but the tested Axis planes were rather old, worn models not representative of the latest types the LW had entering service parallel to the Mustang.

The zoom climb there was little difference, both German models were good at zoom climbs, whereas in the dives the 51 had some advantage. In climbs the 109s easily outmatched it, esp later models, the 190A being about the same, perhaps poorer at altitude, the 190D being better at most altitudes. In dives the accounts are rather mixed,but generally there was not that much difference between WW2 fighters anyway as most would believe in this regard.

Firepower was a mixed matter. The 190A had clearly outclassed it. The 109G is a matter of taste, as a guideline the USN considered three .50 HMGs equal of one 20mm cannon (and the Germans had the advantage of the best cannon rounds, far better than that of the USN had). The P-51 models had either 4 (early models) or 6 x .50s. The 109s base armament was 1x20mm and 2x13mm HMGs, or about 5 HMGs as per the USN's formula - about the same firepower but in a different package. Generally the 'six-pack' of fifties was sufficient vs fighters, but I'd guess they were in for a headache in they'd have to intercept big bombers. The late MK 108 fitted 109s had an extremely devastating gun at their disposal, but it was somewhat balanced out by it's worse ballistics vs. fighters.

Overall, probably the best desrcription of the Mustang would be a fair, good over-all fighter that's best quality was speed and range, and was not exceedngly great or poor in any other regard. A jack of all trades, master of none.

 

[Soundbreaker Welch?]

Those encounter reports of the Mustang pilots are cool and interesting, even if you can't verify all the kills.

 

[Civettone]

Excellent Kurfürst!

I only disagree that the devestation done by the MK 108 was somewhat balanced out by its worse ballistics. I think the MK 108 had sufficient ballistics for short-range combat and that the disadvantage of its lower MV has been systematically overrated.


And apparently, in the beginning of 1945 1/3 of the P-51s still had 4 MGs.

Kris

 

[FLYBOYJ]

And apparently, in the beginning of 1945 1/3 of the P-51s still had 4 MGs.

Kris

That was a pilot option which allowed 400 rounds per gun.

 

[lesofprimus]

The pilots who had the use of the Mk 108 were amazed at its destructive power, as u guys know... The MV was almost irrelevant, as they only used it inclose, ranging the target/bomber with the MGs prior to launching a salvo...

 

[GregP]

P-47 D: Empty: 10,605 lbs; Loaded: 17,411 lbs; Engine: 2,500 HP; Wing Area: 300.3 sq. ft.; Power Loading: 7.0 lbs per HP, Wing Loading: 58.0 lbs per sq ft

P-51D: Empty: 7,639 lbs; Loaded: 11,095 lbs; Engine: 1,475 HP; Wing Area: 233.0 sq ft; Power Loading: 6.5 lbs per HP; Wing Loading: 47.6 lbs per sq ft

Bf 109 G-6: Empty: 5,895 lbs; Loaded: 6,942 lbs; Engine: 1,475 HP; Wing Area: 174.0 sq ft; Power Loading: 4.7 lbs per HP; Wing Loading: 39.9 lbs per sq ft

Spitfire Mk IX: Empty: 4,972 lbs; Loaded: 7,357 lbs; Engine: 1,585 HP; Wing Area: 242.0 sq ft; Power Loading: 4.6 lbs per HP; Wing Loading: 30.4 lbs per sq ft

P-38J: Empty: 14,107 lbs; Loaded: 21,612 lbs; Engines: 2,850 HP; Wing Area: 328.3 sq ft; Power Loading: 5.5 lbs per HP; Wing Loading: 53.3 lbs per sq ft

Fw 190 A3: Empty: 7,053 lbs; Loaded: 8,580 lbs; Engine: 1,700 HP; Wing Area: 197.0 sq ft; Power Loading: 5.0 lbs per HP; Wing Loading: 43.6 lbs per sq ft

The "loadings" above are calculated at Normal Loaded Weight. Most planes never fought at normal loaded weight, particularly the Allies since they had to burn fuel just to GET to the fight. Also, Allied fighters would routinely drop ordnance and/or drop tank before a dogfight.

From the above, the most maneuverable based on wing loading at Normal Loaded Weight would be the Spitfire Mk IX. Of course, things OTHER than wing loading, particularly the choice and cleanliness of the airfoil, affect maneuverability. A dirty airplane was not as good a turner as a clean one, everything else being equal.

The best climber, based purely on power loading, would be the Bf 109 G-6. Again, things other than power loading, particularly the propeller choice and the altitude curve of the supercharger / turbocharger, affect rate of climb.

The Mustang in particular was a very good zoom climber, using momentum to trade speed for height. At faster speeds it could easily out-zoom the Bf 109, but the Bf 109 was better in a sustained climb. Dogfights NEVER involve a sustained climb. Conversely, the Mustang had a relatively high "stick force per g," being in the 25 – 30 pounds per g range at normal center of gravity. So, it was mostly a 3 – 4 g airplane except for emergencies. If the Mustang happened to be fighting at 8,500 lbs, it was very equal to the Bf 109 in all categories, and the Bf 109 had a MUCH smaller fuel fraction, so it was probably much closer to the normal loaded weight than a Mustang that had just flown 500 miles and had dropped tanks and burned fuel from the fuselage tanks.

A few other points: The Bf 109 had no rudder trim and was very tiring to the pilot when out of trim. The other planes did not have this difficulty. The Bf 109's control became VERY heavy at high speeds, making it very much of a "straight line" fighter at 400+ mph, while it was VERY maneuverable at 250 – 300 mph. Hence, the Bf 109 pilot wanted to get the fight slow while the Mustang pilot wanted speed. Similar things can be said for the Spitfire, though not nearly to the degree of the Bf 109.

So … we a re back at the question of exactly HOW to compare the aircraft?

All were good, and we are unlikely to arrive at a "best" since it is 65+ years since WWII and we are still debating it.

 

[FalkeEins]

Overall, probably the best desrcription of the Mustang would be a fair, good over-all fighter that's best quality was speed and range, and was not exceedngly great or poor in any other regard. A jack of all trades, master of none.

...thats got to be the worst description I ever read about the P-51 !!

 

[lesofprimus]

LMAO...

 

[Parmigiano]

Just one technical questio: we always evaluate aircraft engines by power, but there are other parameters, i.e. torque and related power curve.

Is torque directly impacting the performances? For instance providing better acceleration etc.

Now it seems likely that engines with higher displacement may have an higher and better distributed torque, so the 27 liters Merlin should have less torque than a 36 litres DB605, that should be 'worse' than the 44 litres BMW801 that should give in to the big P&W and Wright radials

Is there any documentation of torque measurement for this engines?

 

[Hop]

Torque = (horsepower x 5252) / rpm

Because the prop acts like a continuously variable transmission, meaning the engine doesn't alter speed much at maximum power, torque isn't that useful a figure for aero engines.

 

[FLYBOYJ]

Torque = (horsepower x 5252) / rpm

Because the prop acts like a continuously variable transmission, meaning the engine doesn't alter speed much at maximum power, torque isn't that useful a figure for aero engines.

Great explanation but torque isn't that useful for "recip" aero engines - it's VERY important with regards to turboprops.