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FM/DM threads Everything about FM/DM in CoD

View Poll Results: Are the incorrect British FM killing the enjoyment of the game?
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No 48 24.74%
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  #241  
Old 08-23-2012, 08:29 PM
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Crumpp Crumpp is offline
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Now can you please explain how stick force per G is nothing to do with stability and control without going against everything you contributed to that thread?
I said:

Quote:
Stick force per G is a control characteristic, not stability.
http://forum.1cpublishing.eu/showpos...&postcount=200

It was in answer to your claim:

Quote:
if there was no resistance to input then by definition it has no stability (the nature of returning to original condition) it is that resistance which pulls the controls back to original position therefore the relationship between stability and control force is almost proportional
There are numerous designs that have both very light control forces and good stability. One of them is in my hanger right now. Good stability with light control forces does make for a very pleasant airplane to fly.

It is false that stability and control forces are proportional such that you must have instability to have light control forces. The designer has considerable freedom in the management of control forces.

Please point out in anything remotely close to your claim of:

Quote:
you raised exactly this point yourself in 'that' thread, remember?
Please provide a link to the exact claim you think I am making that is wrong.
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  #242  
Old 08-23-2012, 08:34 PM
NZtyphoon NZtyphoon is offline
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Question is how quickly and how far did the oil pressure drop below the emergency minimum (30 lbs - normal pressure = 60lb/sq.in.) under negative g? Under what circumstances would the oil pressure drop below this minimum, and how long would it take for significant damage to occur to the Merlin, or any other engine? How would this be quantified and replicated in a flight sim?

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Originally Posted by swift View Post
So, do we know if the current overheating issue with all spit versions is a bug or incorrect FM? I really would like to know as I really struggle with these birds.
There shouldn't be a problem as long as your temperatures stay within the limits set by the Pilot's Notes - trouble is now the Merlins overheat far too quickly.
  #243  
Old 08-23-2012, 08:44 PM
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Originally Posted by NZtyphoon View Post

Question is how quickly and how far did the oil pressure drop below the emergency minimum (30 lbs - normal pressure = 60lb/sq.in.) under negative g? Under what circumstances would the oil pressure drop below this minimum, and how long would it take for significant damage to occur to the Merlin, or any other engine? How would this be quantified and replicated in a flight sim?



There shouldn't be a problem as long as your temperatures stay within the limits set by the Pilot's Notes - trouble is now the Merlins overheat far too quickly.
Engine damage in seconds from lubrication starvation, in a Merlin or any other engine. Bearing coatings burns away, piston's are scored...would be nice to have engine proper use pilot notes posted. Many here push well beyond manufacturer use recommendations, that I'm sure of
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  #244  
Old 08-23-2012, 09:24 PM
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Supermarine test pilot Alex Henshaw was once critised by a new manager for doing so much sustained inverted flying (i.e -1g) in Spitfire demonstrations. His reply was (in Sigh for a Merlin p79):

"Spitfires are not flown inverted on test. It is true they are rolled and in some cases an inverted glide takes place, but as the engine cuts immediately on negative 'G', there is no power in use. I have discussed this at some length with the Rolls-Royce technicians and they are happy no damage occurs."

He goes on to say at one stage he and Geoffrey Quill were asked to invert a Spit from 20000 ft and no engine damage ocurred.

Here is the only known footage of Henshaw doing his routine in the movie "Ferry pilot". This is a Spit Va, you can hear the engine cutting during the inverted glides. I wonder whether at this point it was necessary to cut throttle to avoid sustained inverted running as the motor was less susceptible to neg g cutout.

  #245  
Old 08-23-2012, 09:39 PM
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Quote:
Originally Posted by camber View Post
Supermarine test pilot Alex Henshaw was once critised by a new manager for doing so much sustained inverted flying (i.e -1g) in Spitfire demonstrations. His reply was (in Sigh for a Merlin p79):

"Spitfires are not flown inverted on test. It is true they are rolled and in some cases an inverted glide takes place, but as the engine cuts immediately on negative 'G', there is no power in use. I have discussed this at some length with the Rolls-Royce technicians and they are happy no damage occurs."

He goes on to say at one stage he and Geoffrey Quill were asked to invert a Spit from 20000 ft and no engine damage ocurred.

Here is the only known footage of Henshaw doing his routine in the movie "Ferry pilot". This is a Spit Va, you can hear the engine cutting during the inverted glides. I wonder whether at this point it was necessary to cut throttle to avoid sustained inverted running as the motor was less susceptible to neg g cutout.

Keep in mind that possibly the oil pan had been changed out...anyone here having problems should observe their oil gauge as recommended, and learn to alter their flying style. Treat it like a car you just spent a bunch of money on.
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  #246  
Old 08-23-2012, 09:45 PM
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Quote:
I said:


Quote:
Stick force per G is a control characteristic, not stability.
and I said stick force per G is a control characteristic affected by stability



http://forum.1cpublishing.eu/showpos...&postcount=202


So are you saying now that the Spitfire didn't have oversensitive elevators due to longitudinal instability?

Quote:
There are numerous designs that have both very light control forces and good stability
Yes by means of things like servo tabs, stabilators with anti balance tabs, PFC's etc etc......none of which applied to Spits or 109's....nope just good old fashioned hinged control surfaces with nothing but the stability of the aircraft to determine their effectiveness....oh and of course there was the famous 'bob weight'.......strange.....why would increasing control forces make an aircraft more 'stable'? it's almost like theres a relationship between them

Quote:
It is false that stability and control forces are proportional such that you must have instability to have light control forces
if an aircraft is unstable it takes less effort to make it react through control inputs, if it is stable it takes more effort to make it react through control inputs......how is this not getting through?......less effort = light controls, more effort = heavy controls.....is it making any sense yet?

Quote:
Please point out in anything remotely close to your claim of:
I already did but what the hell...here it is again

http://forum.1cpublishing.eu/showthread.php?t=33245


..........
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Last edited by bongodriver; 08-23-2012 at 09:52 PM.
  #247  
Old 08-23-2012, 09:51 PM
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Quote:
Originally Posted by Crumpp View Post
I don't see any difference between them when I play. Have you recorded the Hurricanes stability characteristics?

The Spitfire in game as tested is both static and dynamically stable, something the real aircraft was not.


The issue is will correcting one set of FM parameters make or a more realistic simulation or not? The aircraft represented in the game were on equal footing as dogfighters in the actual battle we are simulating.

I don't think making a frankenplane out of one side is going to accurately represent relative dogfighting capabililties.
Crumpp,

I did say that I would be more comfortable if someone else would fly that test over a longer period. I admit the amplitudes began to decay but there were only three oscillations and I would like to see the flight start from a proper hands-free trim, probably the 2580rpm A&AEE used but with reduced boost (I used maximum) so that the roll motion was eliminated right from the start. Then hands off to see what develops. The stick will of course be dampened by the stick springs although FFB may react differently.

I don't know what started the oscillations because if it was stable they shouldn't have begun. It may have been my hamfistedness trying to get hands-free flight.

So, please don't take my one short test as gospel just because it appears to confirm your belief, it needs more testing and I just don't have the time nor do I want to be the only person that verifies this. My main contribution was in creating the test script.

For anyone willing to give the time here's the link to my thread including the test mission:
http://forum.1cpublishing.eu/showpos...21&postcount=7
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  #248  
Old 08-23-2012, 09:55 PM
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Quote:
Originally Posted by Crumpp View Post
Osprey,

It is defineable and measureable, characteristic.

It is not based on a subjective opinion.



Sorry, I am not up on my gaming lingo.

What is the correct term for a FM that is overmodelled in its capabilities?
"Feel" is absolutely subjective, for example ask any decent golfer if he prefers to use a Titleist ProV1 or a Pinnacle ball - he'll tell you a bit about 'feel', and it's not measured.

"overmodelled"

But you know, if you think the Spitfire is overmodelled then that's laughable, overall it definately isn't.
  #249  
Old 08-23-2012, 10:01 PM
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Quote:
Originally Posted by SlipBall View Post
...would be nice to have engine proper use pilot notes posted. Many here push well beyond manufacturer use recommendations, that I'm sure of

Rolls Royce specify in the notes that you can push past the limits, it is a risk to undertake. It's been published in this thread a few pages back by NZTyphoon.
  #250  
Old 08-23-2012, 10:13 PM
Kurfürst Kurfürst is offline
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Interesting. Reeeallly interesting.

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Il-2Bugtracker: Feature #200: Missing 100 octane subtypes of Bf 109E and Bf 110C http://www.il2bugtracker.com/issues/200
Il-2Bugtracker: Bug #415: Spitfire Mk I, Ia, and Mk II: Stability and Control http://www.il2bugtracker.com/issues/415

Kurfürst - Your resource site on Bf 109 performance! http://kurfurst.org
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