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FM/DM threads Everything about FM/DM in CoD

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  #1  
Old 05-04-2011, 10:18 AM
Viper2000 Viper2000 is offline
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It's not really very useful to say that aircraft x out turns aircraft y unless you specify the conditions more precisely.

For example, in IL2 I could quite easily out turn Spitfires with my Fw190; but only in certain (relatively small) parts of the envelope.

In the case of the Spitfire I and Hurricane I, they should have identical engines, and I think they should have identical props (though this isn't immediately obvious since their top speeds are sufficiently different that it might have been worth designing different props, especially in the early fixed pitch or 2 pitch days).

This means that altitude shouldn't be a major factor, because the engine power should be identical (apart from ram) at all altitudes. Note however that the cooling drag is obviously different, so if you're minded to lump this into the "engine" section of the drag & mass accountancy then YMMV (IMO this sort of distinction is academic until such time as we know how 1c have actually built the models, though I suspect that cooling drag will be part of the airframe model rather than the engine model).

I would expect the Spitfire to outperform the Hurricane in a constant energy turn at high speeds, simply because the Spitfire is faster.

I would expect the Hurricane to achieve a higher maximum turn rate and a tighter minimum turn radius than the Spitfire because its wing loading is lower.

I would also point out that both measures are academic unless you're crazy enough to stay in a turn fight for several complete circles, since otherwise differences in roll rate (and thus turn entry time) will be important; the Spitfire is likely to win here because its span is shorter and therefore it may be expected to have less roll damping, all else being equal (which I know it isn't before somebody starts).

Equally, very few real fights are going to take place at constant "total" specific energy (quote marks used because of course this fighter pilot's definition of total energy is only kinetic + gravitational potential). I would expect the Spitfire to have superior instantaneous turn performance because of its lower stick force per g and higher roll rate; so basically if you're going fast enough to have spare energy for an instantaneous turn, the Spitfire is likely to be able to dump energy into angles rather faster than the Hurricane.

IME, once one aeroplane in a fight starts to develop any kind of advantage, there is a tendency for the losing pilot to pull too hard in an attempt to catch up, which tends to actually make his position worse (because he's then fighting the other pilot's fight instead of his own).

Lots of people around here at the moment seem to pull too hard and get themselves deep on the wrong side of the excess power curve and then complain about the poor aircraft performance which results.

Finally, I would observe that the vast majority of pilots who lived to tell war stories spent very little time at the edges of the flight envelope, especially with regard to sustained turns. For this reason, the majority of accounts stating "Aircraft x clearly out turns aircraft y, because I did this numerous times in combat" are best taken with a pinch of salt.

Statistically, the sample is extremely biased, because dead men tell no tales.

Consider this scenario:
  • I want to find out whether or not it is safe to fly a kite in a thunderstorm.
  • I briefly review the literature, and find that Benjamin Franklin did this successfully and wrote about it.

Is it therefore safe to fly a kite in a thunderstorm? Or was Benjamin Franklin simply a fairly lucky man? The Wikipedia page strongly suggests the latter, but it cites no sources in regard to its claim that:
Quote:
The experiment also garnered attention and many attempted to recreate it. Some of the experimenters are known to have died during recreating the experiment.
I'm not suggesting that there are no references to be found on this subject - I'm just saying that one good "war story" told from the perspective of a "winner" is likely to assume more importance within the general literature than a secondary account of the experiences of those who gambled with their lives and lost.

So, you can find accounts saying that for example Spitfires would easily out turn 109s and you can equally find accounts saying that 109s could easily out turn Spitfires. What these accounts tell you is that the people who won fights tended to write more books about it than the people who lost them.

Genuinely satisfactory comparisons are extremely hard to come by. Genuine A/B comparisons under controlled conditions relied upon the use of captured aeroplanes which were inevitably less than representative of the average service machine (due to such factors as battle damage, lack of proper maintenance, incorrect fuel and lubricants, lack of proper batteries, lack of pilot experience, deliberate over-boosting to investigate development potential, questionable loadouts due to both lack of detailed knowledge and lack of suitable ordnance etc etc).

In fact, even when the aircraft being compared are fighting on the same side, it can be quite challenging to work out what was really going on; sometimes the manufacturer would "cheat" (e.g. Quill using a Spitfire XII in the race between Typhoon(?), Fw190A3 and Spitfire, making the political point that the Spitfire still had considerable development potential despite claims to the contrary from certain quarters perhaps not a million miles from Kingston). Sometimes you'd find that one pilot was better than the other. Sometimes you'd get a good example of aircraft x vs a bad example of aircraft y (the tolerances were pretty large even at the point of manufacture, and tended to grow in service as mods, wear and tear took their toll; or indeed as careful maintenance and clean-up work improved performance of certain special machines quite considerably - e.g. a few specialist high altitude Spitfires locally modified for extreme altitude performance to deter Ju86 overflights at FL400+).

So there's enough ambiguity for a thousand chart-wars.

IMO it is therefore much more sensible to attempt to match concrete aircraft performance data from original test data compiled for or by the intended end-user of the aeroplane, and to treat turn performance as an emergent behaviour.

If the other performance characteristics, which were defined and recorded in a considerably more satisfactory manner, are all matched, then it follows that the emergent turn performance is likely to be pretty accurate, because it's extremely unlikely that a good match across a number of known parameters (TAS vs altitude, stall speed, ROC vs altitude etc) would be dramatically wrong for unknown parameters (in other words, if I've got a car type, a colour, and a partial number plate, I am quite likely to have enough data to fill in the blanks because although there are lots of cars on the road, relatively few will pass through all of these "filters").
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  #2  
Old 05-04-2011, 11:18 AM
deadmeat313 deadmeat313 is offline
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Excellent post Viper2000!

However, we need to keep this debate going somehow, so errrr - I often find that my Hurricane barrel rolls much slower than I thought it would (based on a dream I had once with a Hurricane in it).

Fix pls Oleg!


T.
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  #3  
Old 05-04-2011, 11:35 AM
Sven Sven is offline
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Well now that I think of it, in IL2 1946 4.10.1 spitfires also easily outturn hurricanes at any speed * ( As well as the newest M*d packs),
and that has been this way since the beginning as far as I remember (Forgotten Battles), not saying that that is what it should be, maybe time for revolution?

*Read for that underlined text: barely outturn it.

Last edited by Sven; 05-04-2011 at 12:06 PM.
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Old 05-04-2011, 11:44 AM
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Kwiatek Kwiatek is offline
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Quote:
Originally Posted by Sven View Post
Well now that I think of it, in IL2 1946 4.10.1 spitfires also easily outturn hurricanes at any speed ( As well as the newest M*d packs),
and that has been this way since the beginning as far as I remember (Forgotten Battles), not saying that that is what it should be, maybe time for revolution?
You havent tried Ultr@Pack 2.01? Haven't you?

Hurricane MK 1 +12 lbs is very close to SPitfire MK1 +12 lbs in UP if not little bit better at lower speeds
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  #5  
Old 05-04-2011, 11:47 AM
Sven Sven is offline
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I find it very difficult in the Hurri to keep up with a Spit in UP 2.01, I mainly fly HSFX 5.0 now so my memory might be off.

EDIT: I just fired it up and can get them in a stable sharp turn and find the Spit to be quicker but it is indeed very close, but that's just feelings.
You are right though that when speed drops to 200 the spit has a harder time keeping up, and I have to let the elevator go a bit to prevent falling down to the earth, whilst the Hurri can push some what further.

Last edited by Sven; 05-04-2011 at 12:04 PM.
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Old 05-04-2011, 02:51 PM
ATAG_Doc ATAG_Doc is offline
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I am sure if we could go back in time and we were actually there and were all part of this, and we each had our plane we'd know what's up. What turns better and what is faster. What to do in a given situation. Because we have it at our disposal at any time we wanted to see and test. But this is a sim. There is and always will be differences based on the interpretations of a given developer.
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  #7  
Old 05-04-2011, 06:52 PM
Viper2000 Viper2000 is offline
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Quote:
Originally Posted by timej31 View Post
I am sure if we could go back in time and we were actually there and were all part of this, and we each had our plane we'd know what's up. What turns better and what is faster. What to do in a given situation. Because we have it at our disposal at any time we wanted to see and test.
Not really. You'd get to fly the type of aeroplane you were given and for most people that would be it. So you might know quite a lot about for example the performance of the Hurricanes your squadron flew, but you wouldn't know very much about the performance of the Bf-109.

People would hear things on the grapevine. Some bits would be closer to the truth than others. Obviously a significant proportion of people who discovered the enemy's performance advantages didn't live to tell anybody about it...

During the Battle, quite a lot of RAF pilots said in their combat reports that they were fighting the He-113 rather than the Bf-109. So much for "knowing" about the enemy's performance...

In fact, it was quite possible to fly a whole tour without seeing an enemy aeroplane at all, especially for Allied pilots later in the war. It's also worth observing that pilots who were trained during the war didn't necessarily get an awful lot of hours in which to experiment with the limits of aircraft performance, because the priority was operations rather than training. And the priority of operations was to attack ground targets and conduct reconnaissance. Fighters only exist to interfere with, or prevent interference with, the aeroplanes attempting to perform this useful work. AFAIK the average pilot in a WWII airforce was not a fighter pilot, though he might have told the girls otherwise.

Later in the war, more concerted efforts were made to convey the strengths & weaknesses of enemy aircraft to pilots, though of course this intelligence information was imperfect.

Since the best tactic to employ against an uncooperative enemy aircraft is entirely a question of relative performance, it follows that aerial combat was mostly a game of extremely high stakes poker.

For this reason, it was an extremely bad career move to actually get into the sort of fight whose outcome depended upon aircraft performance; the vast majority of aces scored their kills by exploiting their opponent's lack of SA and shooting them in the back rather than by getting into aerobatics contests with them.

Of course, if you score most of your kills by bouncing the enemy then you don't know or much care about the turn performance of his aeroplane; you care more about the operational habits of enemy pilots, such as the speeds, altitudes and types of formation in which they are inclined to cruise.

So even the best WWII fighter pilots probably knew considerably less about his opponents than the average sim pilot does.

A consequence of this is that sim pilots tend to make a bigger deal out of small performance differences.

If I feel inclined, I can spend a week or two testing the performance of all of the flyable aeroplanes in the sim. I can discover the 5% performance difference between aircraft x and aircraft y, and I can exploit that performance difference in combat with considerable confidence, leading to many forum posts about aircraft x's performance advantage over aircraft y.

IRL, production tolerances and pilot skill would render this sort of 5% performance difference entirely irrelevant; the absence of a refly button means that winning "most of the time" just doesn't cut it. Mixed reports of the outcome of turn fights would filter back to the squadrons, and the consensus would probably be that turn fighting was a bad idea in general, and an especially bad idea against aircraft y, because the success rate wasn't great.

It's very hard to get away from the fact that the massive psychological differences between fighting in a real war and playing with a flight simulator have a correspondingly massive impact upon the way that people fly, fight, and even think about their aeroplanes.
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  #8  
Old 05-25-2011, 02:40 AM
Danelov Danelov is offline
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Why do Spitfires turn better than Hurricanes?!

Easy, the magic wings of Mr Reginald Mitchell, that is all.
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  #9  
Old 05-25-2011, 02:48 AM
Formula88
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A better question is why do Hurricanes out climb and are faster in level flight than 1a spits...
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  #10  
Old 05-25-2011, 03:05 AM
609_Huetz 609_Huetz is offline
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C
S
P



On a serious note, it's a pain in the a** to see a historical flaw like that ingame day after day.
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