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### Why is the Aerodynamic Centre not affected by changes in Angle of Attack? [duplicate]

I understand that the Aerodynamic Centre (AC) is the point in the aircraft where the pitching moment never changes with a change in Angle of Attack (AoA). My understanding of the Centre of Pressure (...
1 vote
430 views

### Why is subsonic lift at 25% of chord? [duplicate]

I pretty much understand the way a wing works and the different ways of explaining it, what I don´t understand is why the lift on a subsonic wing manifest itself at the 25% chord.... The 50% chord ...
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### Is the Centre of Gravity moved by an aircraft travelling at “High Speeds”?

The following quote is from G. Bristol’s book, Ace the Technical Piloting Interview: [The] movement of the centre of gravity is due to a change in weight. The distribution of the aircraft’s weight ...
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### Is a trimmed flight not always an unstable system?

As soon as I am flying in trimmed flight condition, my pitching moment around the center of gravity becomes zero. So my center of pressure has to be located in the center of gravity, so that there is ...
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### Why do tailplanes provide down force, if not for longitudinal static stability?

We can see that most conventional aircraft have their horizontal tail surfaces arranged to provide a down force. This question asks if that is required for static longitudinal stability, and the ...
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### What is the physical meaning of Mean Aerodynamic Chord?

I have not been able to find a consistent definition of what it really is. I have come across definitions such as: "Physically, MAC is the chord of a rectangular wing, which has the same area, full ...
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### Where is the best center of gravity?

I'm designing a plane, and I have a question. What is the best place for the center of gravity, relative to the center of lift? I've heard that it's best put just behind the center of lift, but I ...
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### How does centre of pressure change with angle of attack?

I've been given the distance of centre of pressure from the leading edge with a certain angle of attack and was wondering if it's possible to calculate the new position when the angle of attack ...
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### Center of Gravity and Center of Lift stability

I have recently been reading about the center of gravity and center of lift. On the German Wikipedia there are many different graphics about the relation between the center of gravity and the center ...
1 vote
11k views

### Why should the centre of mass be ahead of the centre of pressure?

Why is the centre of mass located ahead of the centre of pressure? And what would happen if centre of mass would be too close or too far away from the centre of pressure?
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### Are the vortex generators on the Cessna Caravan necessary and sufficient for safety of flight?

I've been doing some reading about the C208B (Cessna Caravan) in prep for my new job flying cargo; I came across this article which (as far as I can tell) is a transcription of litigation surrounding ...
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### Why do we calculate the pitching moment coefficient about quarter chord point?

Why do we calculate the pitching moment coefficient about quarter chord point, when force and moment system can be transferred to any convenient point?
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### How does the vertical height of the wings on a plane affect flight relative to its position? E.g., how does a higher high wing affect flight?

I think I understand how a high wing differentiates from a mid wing or a low wing; what I am asking is how, for instance, a very high high-wing makes itself unique in flight from a very low high-wing. ...
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### Why does centre of pressure (drag?) move forward when transitioning from transonic to supersonic?

I am studying aerospace engineering at college and I am wondering why the centre of pressure moves forward when the aircraft changes from transonic flight to supersonic flight? Also, is centre of ...
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1 vote