vtracy wrote: ↑08 Nov 2020, 03:59
Dudley,
with all due respect (as they say so often in war films): The whine/whistle of the 109 is not (predominantly) from some opening. It is, I believe, a true supercharger sound. That is why I mentioned my BMW. Whenever I revved the engine, I could hear the turbine whine go up the frequency. Although it was a diesel engine, it was so well encapsulated that one could hear the turbine (a testament to the culture of the 6-cyl technology).
So, my conclusion: your planes may produce their sound by „external means“ (like a Stuka‘s sirens
), my Me 109 whines from within. (After all, she has to hace at least something better than the superior US fighter ...).
Volker
I understand your opinion and I certainly respect your right to express it and the subject of the "whine" certainly isn't important enough to cause hard feelings between friends on this forum.
I have no doubt at all that you might very well be able to hear the charger installed inside a car. A fighter plane at high speed however is another matter. At high speed and especially in curved flight where g is increasing and angle of attack from the relative wind is striking various openings the total sum of the produced sound from this would certainly drown out any internal sound emitted from a supercharger. Also, you will note that the "whine" you are hearing isn't constant. Even considering doppler effect the whine changes in intensity as the fighter changes its attitude in pitch. The supercharger on the other hand, in the case of the Mustang anyway, at the altitude we are discussing here such as viewing a display, is operating at a constant speed. In the case of the P51 for example, the low blower ratio as I recall is around 6.391 x the crank speed. In high blower which is never used at low altitudes, that ratio is bumped up to around 8. something. The sound you are hearing from the famous "whine" is varying in intensity so it can't come from the charger which is operating at a constant speed in relation to the engine crankshaft.
Acoustic experts the world over have studied the issue of the famous whine and the consensus is as I have described in my prior post.
I certainly, as I said respect your right to an opposing opinion. I can only comment here on this forum as that relates to my personal experience flying these warbirds and discussing these issues at various times in my career with world class experts.
Fear not however..........the argument over the source of the famous "whine" will no doubt go on long after I am gone. LOL
Dudley Henriques
), my Me 109 whines from within. (After all, she has to hace at least something better than the superior US fighter ...).
