Originally Posted by
psgugrad
I'll chose not to, and thanks for your kindly allowing me to do so. Here's a simple thought process I'll take you through to demonstrate why:
Imagine, all other factors being equal (which they usually are not, but just for illustration purposes), switching from 0% to 10% fuel increases your engine's rpm from 12,000 to 13,000. That's an 8.3% increase in RPM. Now factor in the fact that as a prop spins faster, diminishing returns kick in...this means that in this example the 8.3% increase in rpm will not result in an 8.3% increase in thrust being generated by your engine-propeller combination (ask any mechanical or aeronautical engineer if you don't believe me). I don' know exactly how much the difference would be, but I know it would be something significantly less than 8.3%. Are there more flyers who would notice that the nitro makes their engine easier to tune, or are there more who would notice something along the lines of a 5% increase in thrust? I would guess the former by a wide margin.
There's no need for us to argue semantics, but your assertion that it's the "end of the story" that nitro's main function is to increase power is akin to asserting that it's the "end of the story" that the main function of beer to enable one to get intoxicated. Drinking enough will certainly do that, but some people just want to have a few with a pizza. In other words, it's not the "end of the story" at all. It's simply your opinion.
You would think that the velocity of the air would increase in proportion to the RPM but actually it does not. Also consider that the resistance of the blade will increase by the square of the velocity so that HP actually is much higher than 8% in your case. I ran this though a propeller calculator and the thrust was about 20% higher for your 8% increase in RPM. Now we have started another discussion I guess.