Linked Questions
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How are the glide polar and L/D ratio charts related?
We know from other questions and answers that airplanes and gliders in particular can have their performance described in terms of glide polar and Lift-to-Drag ratio.
As it appears from the images in ...
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6
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2
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Is the maximum lift-drag ratio found at minimum drag?
Figure 10-5 of the FAA's Pilot's Handbook of Aeronautical Knowledge shows:
I didn't think $L/D_{MAX}$ coincided with $D_{MIN}$. Is this Figure accurate?
user2168
7
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3
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Why is the L/D ratio numerically equal to the glide ratio?
*L/D is ratio of two forces, lift and drag.
*Glide ratio is ratio of two distances.
Can you explain mathematically how they end up numerically equal and are they always equal?
user52248
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4
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Are there any situations where having high lift but low lift to drag ratio would be beneficial?
From my understanding, high lift to drag ratio could make an aircraft efficient during cruising conditions. This is when the aircraft is in equilibrium, lift is equal to weight, and thrust is equal to ...
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3
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3
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What is physics explanation for minimum sink rate airspeed?
I did some research on Minimum Sink Rate, and saw much information defining it, (such as it is the speed at which the aircraft will remain in the air for the longest time, etc.) and how it is ...
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'Gravitational' power vs. engine power
A glider gets the power it needs to fly from the decrease of gravitational potential energy associated to the descent. My question is: for the same weight $W$, airspeed $V$, and a prop efficiency of ...
- 11.2k
4
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Can weight reduce a plane's glide ratio?
The FAA says glide ratio doesn't change, regardless of weight, here on page 5-7.
Glide ratio is not affected by weight because,
while a heavier glider sinks faster, it does so at a greater
airspeed. ...
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0
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4
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How does increasing the angle of attack increase the lift?
When the pitch of a plane increases (facing upwards), it has a positive angle of attack, and when it decreases to face downwards, it has a negative angle of attack.
Increasing the angle of attack ...
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2
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What does deploying landing flaps do to the (L/D)max and minimum drag speed of an airplane?
I thought that deploying flaps will increase both the drag and lift, thus increasing L/D ratio? But do they increase proportionately? And how exactly does that correlate with the increase/decrease of ...
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-1
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2
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If i have equal lift and drag, do they cancel each other out?
I am working on a throw glider and was wondering, How much lift would be too much lift, as in it causes the glider to stall (maybe thrust that causes this, but still). also, if I create a body that ...
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Descending on a given glide slope (e.g. ILS) at a given airspeed-- is the size of the lift vector different in headwind versus tailwind?
We had a discussion with friend and we were talking about if the airplane is on approach and the one is landing with tailwind and the other one is landing with headwind, so both have the same value of ...
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2
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Does an airfoil drag coefficient takes parasite drag into account?
Im trying to understand why does L/D MAX, (the top of the polar curve that computes CL & CD ratio for any airfoil) is also the lowest point of the total drag curve.
Im guessing the reason is that ...
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