ProfessorStein said:Does GPS work at a quantum level??
Monte55 said:If the downward air from the props had nothing to push against, there can be no lift. The shape of the props make them efficient but the props could be flat and still provide lift or thrust. It's the angle of attack to relative air. An airplane could fly with flat wings with no airfoil shape . The angle of attack provides the lift. Wouldn't fly very well though. I do have a bit of a clue since I have messed with aircraft all my life, got my pilots license in 1985. Been building and flying rc aircraft for the better part of 30 years.
Monte55 said:WHAT.chuddly said:and lets confuse it more than that. Its not actually the thrust down of air that lifts it but also and more the lack of air pressure behind the lead edge of the blade that lifts/sucks its up
It's not being sucked up. The down thrust of air pushing on air below the quad from the props is what makes it go up providing the thrust can overcome the weight of machine. No air such as in a vacuum....no lift at all.
poor Bathy....your brain never stood a chance LOL. Sorry for the super in-depth conversation. But essentially the props work because the difference in air pressure above vs. below and as air is moved downward there is a low air pressure region formed just above the prop. This causes the prop to be pulled up into that region more providing lift and picking the quad up into the air. when the blades spin faster a greater pressure difference is caused making the quad go up faster. When they spin slower there is less pressure difference and not enough lift for the weight of the quad to overcome gravity thus causing it to descend. its more about what happens on top of the prop than what happens under it. to more left the left motors decrease in speed and that side of the quad dips slightly because that side of the quad can no longer overcome gravity and it causes it go left. It gets more complicated from there on out...but i hope this helps you understand it???Bathy said:I got headache lol
chuddly said:This is the reason there are jet drag cars with TONS of thrust but no lift and they stay on the ground
Navman said:Finally, proof that Phantoms suck :mrgreen:
ProfessorStein said:chuddly said:This is the reason there are jet drag cars with TONS of thrust but no lift and they stay on the ground
Eh. There is lift on those rocket cars, simply from the body. Most will have an inverted airfoil to attempt to push them downward into the ground. I used to think that's why they called them "drag cars"... but I dont think that's true. But it IS why even those crazy petrol drag racers are so high in the back (that, and to use larger wheels to increase torque to the track). The trick is to have just the right amount of downward thrust so it doesn't add TOO MUCH friction and drag to the wheels, unduly slowing you forward progress.
But some of those rocket cars... if they hit so much as a stone, they pop off the ground and go flying. Again... most of that is the innertia created by the engine, though.
chuddly said:but this is all off topic LOL
Monte55 said:I think what people don't understand is the term SUCTION.
ianwood said:According to NASA, lower pressure on the upper surface is not the primary source of lift and AoA and deflection of air downward is the primary source of lift.
http://www.grc.nasa.gov/WWW/k-12/airplane/wrong1.html
ProfessorStein said: