Quote:
Originally Posted by Targ
This is directed at people that were thought it was off and to sensitive.
What are your thoughts on it now?
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First of all we no longer have a ridiculously overmodelled reduced G effect for the Merlins.
Secondly we do have an engine cut on heavily reduced or -ve G which hits performance and is a lot nearer to the truth than the original. I haven't had the opportunity to pitch it against a diving 109 yet.
Lets think about what might be right. We all want that. Someone posted reduced/negative G notes from the pilots General Flying Notes, well these are not specific Merlin notes. I set a lot of store by a current Hurricane I pilot's actual flying experience and opinion and frankly there's a lot of guessing and wishful thinking going on here from people who have never flown one themselves. Even carefully calulated assessments may not be correct although Viper's calculations are detailed, explanatory and pretty close to what our friendly pilot has said. Just how much nearer to the truth do you think you are going to get without specific Merlin notes and performance charts?
So much for what might be right.
But, is it now modelled correctly? I don't know, I suspect it might be a little off (pure speculation), and I was surprised when Luthier said:
"* Completely removed overload assessment from carburetters. Rolls-Royce engines will now cut if overload is negative, and will not cut if it is positive. (old values were sneezing at .5G, and cut-out at .25 which we felt were dead on, but this apparently confused most of the players)"
His original values of 0.5G and perhaps 0.25G weren't that far off what we have been hearing from good sources. So why did we have problems? One or two people may have touched on the answer. If the onset delay was not included or modelled reasonably we may well have had problems because the starvation and rich cut were not instantaneous but they appeared to be instantaneous in level flight assuming there was some turbulence.
Currently we have a workable Merlin engine model. The engine does cut, as IvanK has demonstrated, and more sensibly than it did before. No it won't STOP if only due to windmilling and if I understand Viper correctly he is saying that there may still be combustion occurring at some level. The 109s still have an advantage diving away.
In the longer run 1C may have time to review how they are modelling this and perhaps find a need to revise it, just as they may need to look at the 109 pilot's gripes, but meantime the Merlin is reasonably on track.
At the moment there are now many other issues that need sorting (which may well include any performance issues for the 109).