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5 Degrees of Separation

My flying hit a plateau, so I tried to force some speed on myself by flying at 50 degrees instead of my usual 45. I thought it'd be a minor adjustment but it was waaaaay faster and harder to hold altitude. I kept hitting the ground on hairpins because I wasn't used to how aggressive I had to be on the throttle. I couldn't understand why 5 little degrees could make such a big difference, so I did some math.

Let's say you're flying at 45 degrees and holding altitude. 71% of your total thrust is directed down and  71% is directed back. Now let's go to 50 degrees. Now you have 64% going down, 77% back.

Who knew Solidworks would be perfect for thrust illustrations too?

So now you have 8% more thrust directed backwards (.77/.71 = 1.08), which is faster but not THAT much faster. So why did it feel like a quantum leap?

This is where I spotted my mistake. The vertical component at 50 degrees is .64 versus .71, which means the quad is losing altitude. So let's readjust those triangles so that the quad holds altitude.

Now you have to apply 10% more throttle to hold altitude, which results in 20% more forward thrust (more throttle and more % of throttle dedicated to forward thrust). Now, that doesn't mean you'll be going 20% faster since aero drag increases exponentially, but it's still a LOT faster. Also, with a smaller percentage of total thrust dedicated to lift, bigger stick movements are required to correct for altitude loss. 

Swapped the numbers around to make the thrust gains easier to see (apparently Solidworks doesn't believe in rounding up. That number is 1.197). Math is easier with drawings instead of calculators.

So the net effect is that I'm flying much faster, which is a bit unnerving in itself. Not only that, the throttle stick is centered around a higher, less familiar position, and corrections require bigger, more aggressive movement. No wonder I couldn't fly at all.