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Old 07-22-2015, 02:55 PM   #11
saburo_cz
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Quote:
Originally Posted by otto View Post
The p51 turns better than the 109.
This is true.
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Old 07-22-2015, 03:23 PM   #12
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Quote:
Originally Posted by saburo_cz View Post
This is true.
What altitude, what speed range and what load. It all matters. You can't just say plane A turns better than plane B. In some cases differences are more pronouced... but not in case of Me109K4 vs P-51D

For both planes with standard loads:
At high speed IAS (550-750+ kph) at low alt 0-3000m, P-51D is going to turn better than 109 simply because the 109 pilot won't have enough strenght to pull. At around 300-450kph the difference between those planes will probably be impossible to track. Both pilots would probably be able to turn simillarly. At speed bellow 300kph, the 109 is going to have an advantage in a sustained turn and pushing the nose into vertical will create a situation where the P-51 pilot will be unable to follow (beeing heavier and having less power).


At high altitude(7000-9000m) it would also be close, but P-51 should be able to outturn the 109.

*Disclaimer! All numbers are rough estimates based on my personal experience with DCS and other simulations and many read books and articles.
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Last edited by Solty; 07-22-2015 at 03:31 PM.
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Old 07-22-2015, 03:56 PM   #13
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What Solty said. At normal multiplayer altitudes, sustained turning ability matters more than instantaneous turn, in general, because the fight drops down to sustained speeds quickly. You can't keep up a high-speed fight for long unless you've got loads of altitude to burn.

More importantly, a fighter that only turns better at high speed needs to start out with an altitude advantage over his opponent, because these high-speed turns bleed too much energy to do it in a normal situation; in a standard duel merge, by the time the P-51 has "gotten behind" his opponent, his opponent is now too high above him to reach before stalling. And now the opponent can do a nice sustained turn overhead, out-turn on a higher plane, then roll over for the attack. "Out-turn him at high speed" is something that people always recommend to pilots of lesser-turning aircraft like the P-51, but it only works in situations that are unusual in a co-X fight.

So, again, my objection: "The P-51 turns better than the 109" is technically true, as part of a larger statement ("the P-51 turns better than the 109 under specific conditions"), but the implied meaning from leaving the statement unfinished like that is dishonest, because the implication is that the P-51 usually or always turns better than the 109, which is false more often than it is true (in normal multiplayer battles, which tend to occur somewhere around ten thousand feet).

In the end, what I see is players with a 109 that's performing better than the P-51 (because the P-51 is underperforming for several reasons), expressing disappointment that the 109 isn't doing even better, and then pretending that the P-51 has the advantage (when it usually has the disadvantage, under these conditions). I can't see it as anything else but intellectual dishonesty & poor sportsmanship.

Last edited by Echo38; 07-22-2015 at 04:01 PM.
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Old 07-22-2015, 04:03 PM   #14
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Seems like this is drifting off topic a little guys, lets be careful...
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Old 07-23-2015, 01:08 PM   #15
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Quote:
Originally Posted by Solty View Post
What altitude, what speed range and what load. It all matters. You can't just say plane A turns better than plane B. In some cases differences are more pronouced... but not in case of Me109K4 vs P-51D

For both planes with standard loads:
At high speed IAS (550-750+ kph) at low alt 0-3000m, P-51D is going to turn better than 109 simply because the 109 pilot won't have enough strenght to pull.
Even if we assume that the 109 pilot can't pull as much Gs at high speed as the P-51 pilot, it will be only true for instantenous turn rate since the "g-pull limit" advantage will be in speed regions which cannot be sustained on any prop job during manouvering. So its at best a very brief turn advantage before the speed bleeds down quickly.

At high speeds sustained turn is so limited because of repidly increasing drag that any sustained turn will be marginal and unsuited for any combat manouver.

The only possibility of having better high speed sustained turn is either lower parasitic drag and/or higher thrust - and the 51 certainly will not have higher thrust, since its engine is weaker, at all altitudes.

Which leaves parasitic drag, where the 51 may have a very slight advantage or parity, the question is, whether it is enough to not only offset, but exceed the thrust advantage of the 109K... given the great similarity in top speeds, its may be just enough at lower altitudes for parity, but certainly not for greater excess thrust, especially not at altitude.

Quote:
Originally Posted by Solty View Post
At around 300-450kph the difference between those planes will probably be impossible to track. Both pilots would probably be able to turn simillarly. At speed bellow 300kph, the 109 is going to have an advantage in a sustained turn and pushing the nose into vertical will create a situation where the P-51 pilot will be unable to follow (beeing heavier and having less power).
Again, roughly the same physics apply and same power and drag characteristics are possessed at any but extreme high speeds near Vne, except that parasitic drag becomes less and less important, which is why the 109 turn advantage increases.

Quote:
Originally Posted by Solty View Post
At high altitude(7000-9000m) it would also be close, but P-51 should be able to outturn the 109.
Why? Aspect ratio, overall drag in turns (=less drag) high altititude propeller efficeny and engine output (=more thrust)...? High altitude is essentially analogous low speed turning environment.


*Disclaimer! All numbers are rough estimates based on my personal experience with DCS and other simulations and many read books and articles.
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Old 07-23-2015, 11:10 PM   #16
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As long as it is only flat turns, as P-47s out turned 109s.
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Old 07-24-2015, 06:24 PM   #17
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Wait, what? At least at normal altitudes, the Thunderbolt didn't come close to out-turning 109s in sustained turns. In the two or three wartime graphs I've seen of sustained turning circle comparisons, the Thunderbolt was way behind the 109 & P-38 et al, and considerably behind the P-51 as well (which, in turn, was behind the P-38 & Me 109). The only major fighter that the P-47 could flat turn with, for more than brief times, was the FW 190.

At extremely high altitudes, where the P-47 was really at home, that might change; perhaps there, the Thunderbolt could out-turn the 109. But we don't usually fight at angels 30 & 40 in multiplayer.
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Old 01-21-2020, 10:13 AM   #18
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I know this is a very old thread however does anyone know the conditions that the climb tests were performed at, i.e the IAS
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Old 01-22-2020, 08:48 AM   #19
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Quote:
Originally Posted by otto View Post
As tested by DavidRed and other talented pilots.The p51 turns better than the 109.Less talented pilots have a different opinion.
I think you wanted to say "P-51 has much more manageable stick forces then bf 109".
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Old 01-23-2020, 01:32 PM   #20
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Any one have power chart for db605db ??
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