British FM killing the fun of the game for allied pilots.

[Robo.]

Originally Posted by Crumpp

Ok, so what you guys want is an airplane that is as fast as the Spitfire, climbs as well as the Spitfire, turns as well as the Spitfire, but acts like the Hurricane?

In otherwords a frankenplane that never existed during the Battle of Britain?

I don't see where that is any more realistic than the FM's in the game now you are all complaining about.

What are you talking about here?

[NZtyphoon]

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?

Originally Posted by swift

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.

[SlipBall]

Originally Posted by NZtyphoon

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

[camber]

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.

http://www.youtube.com/watch?v=nCmzYccyBYM

[Osprey]

Originally Posted by SlipBall

...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.

[NZtyphoon]

Originally Posted by SlipBall

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

I'm sure it happens - what is needed is some empirical data to show how long it takes for the oil pressure to drop below the minimum safe level. How much negative g is needed to lower the oil pressure enough to cause damage? The Pilot's Notes General, for example, describes one condition imposing too much negative g is a succession of slow rolls - so how many pilots are going to indulge in successive slow rolls during combat? What other combat conditions will impose enough negative g for long enough to damage the engine?

The normal oil pressure for the Merlin is 60lbs/sq.in, with a working minimum of 30lbs/sq.in. For gameplay a rough rule of thumb could be anything below 30lbs and the engine begins to suffer progressive wear (according to the Pilot's Notes General it doesn't take long for damage to occur once the oil pressure drops below the minimum).