Questions tagged [lift]
The force acting on an aircraft in opposition to gravity which keeps the aircraft in the air.
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Downwash, Lift-Induced Drag and Wing Tip Vortices [closed]
I've been reading many of the answers that Peter Kämpf and
Jan Hudec have posted over the years. After many hours of reading the responses here, reading Anderson's Performance and Doug McLean's ...
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By what principle is the lift coefficient calculated without first knowing the lift? [closed]
Or air density, or velocity, or wing area? Question: What principle is applied in the calculation and determination of the lift coefficient? The lift coefficient just seems to be a number. How do ...
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How does lift depend on velocity in 3D?
Many resources provide the following type of cross-section view when explaining aerodynamic forces:
The textbook says that $V_a$ is the speed of the aircraft through the surrounding air mass.
Does ...
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Why does the Neutral Point not vary with Tail incidence angle?
The neutral point is the position where if the CG were present, the aircraft would be statically neutral, ie., the moment about the CG would be constant with varying AoA.
Now, consider an aircraft ...
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Why will the max lift point not be at the center of a swept but constant chord wing?
(In this question when I say "swept wing" it means the blue wing seen at the bottom. So no fuselage or anything) If you look at this graph from this answer, you'll see the max lift point of ...
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How do planes deal with excess lift at high speeds?
If I understand correctly, wind force increases quadratically as airspeed increases. Therefore, all other things being equal, lift should also increase quadratically. Does that mean, a plane going ...
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How does the air molecules provide wing lift force when only wing is moving or when only the air is moving?
We use to calculate lift force of a wing as function of air speed squared.
We can imagine 2 different situations:
1 - the wind has speed thus kinetic energy and momentum while the wing is stationary
2-...
user76006
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wave drag: Lift coefficient in Korn's Equation
I have been using the Korn equation:
$$
M_c = \frac{0.95}{cos(\lambda)}-\frac{t/c}{cos(\lambda)^2}-\frac{C_L}{10cos(\lambda)^3}-\sqrt[3]{\frac{0.1}{80}}
$$
to estimate the critical mach number of a ...
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Lift without aerofoil? [duplicate]
I have seen some RC planes flying without any form of airfoil, the wing is literally a flat board.
What I want to understand is how lift is generated under these conditions. I understand kinetic ...
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How can the wing generate more lift than the thrust? [duplicate]
I recently checked about the max takeoff weight of an A380 and the thrust it can provide at TO/GA power and I was quite shocked by the results. The total thrust by the engines was only about 127000 ...
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In a hot air balloon what proportion of the lift comes from the heated air compared to that from the combustion products?
A hot air balloon is heated with propane or similar hydrocarbon. One of the products of combustion is H2O with molar mass 18 so it is substantially less dense than air (78% nitrogen, molar mass 28 and ...
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How does the lift-to-drag ratio depend on absolute sizes?
A dependency is provided here
$$(L/D)_{\max} = \frac{1}{2} \sqrt{\frac{\pi \varepsilon ~ \mathrm{AR}}{C_{D,0}}}$$
AR significantly affects the outcome in this dependency. AR varies significantly among ...
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Does more lift cause a plane to stall at a lower airspeed?
Does more lift cause a wing to stall later? (By more lift I mean a bigger wing) I was looking and saw this question, but the answers didn’t really address why more lift will help a plane not stall.
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Which is more efficient, thickening an airfoil or adding a bottom-surface curve?
So if you were to take a standard airfoil and increase the thickness, you’d increase the lift (Bernoulli’s principle), but it would also increase the drag.
Now imagine you have the same airfoil, but ...
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Conundrum about designing a glider relating to coefficient of lift
I'm designing a high-altitude glider. Just to clarify a few points before my question:
The glider will weigh close to 200 grams.
It will be using the A18 airfoil.
The glider is dropped from 80,000 ...
