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1 vote

Which airplane has the biggest ratio of Vne to stall speed?

Re "of airplanes that cannot hover" -- if you are at all familiar with "3D" model-airplane flying you will have seen all kinds of videos of maneuvers involving airplanes hanging on ...
quiet flyer's user avatar
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-1 votes

Which airplane has the biggest ratio of Vne to stall speed?

The Antonov AN-2 has no declared stall speed. So even with a maximum speed of 258 km/h, it has an infinite ratio of stall speed to vne. Rumours give the stall speed at 40 km/h. So a ratio of 6.5. The ...
EarlGrey's user avatar
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5 votes

Which airplane has the biggest ratio of Vne to stall speed?

According to the following flight envelope (source), at sea level the F-15 has a maximum speed of Mach 1.2 and a stall speed ($C_{L_{MAX}}$) of 0.1, giving a ratio of 12. The F-14 comes close (source)...
sophit's user avatar
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4 votes

Which airplane has the biggest ratio of Vne to stall speed?

A good candidate is an airplane which has good high-lift devices for landing while being designed to go fast at low level. A swing wing helps, too. So I propose the B-1A or B-1B Lancer. Specs are hard ...
Peter Kämpf's user avatar
0 votes

Can a single-bladed rotor with cyclically varying torque emulate a swashplate?

Probably not as you describe. You would need to vary the speed of the rotor throughout the revolution. You might need to double or halve the speed for part of a rev -- that much acceleration would ...
Rob McDonald's user avatar
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3 votes

How would you know the difference between a compressor stall and a surge based on indications in the cockpit?

Stall and surge are two different, although related, physical phenomena. Stall: One or more blade stages exceed the critical AoA, the airflow is turbulent, and the smooth airflow through the ...
El_Muntagnin's user avatar
1 vote

What are the correct Cd0 and Cdi values for a NACA 2412 airfoil?

My quandary is that if all this is true, there should be a noticeable deceleration when the aircraft is rotated at 55 knots while taking off, resulting from a doubling of drag. This is not observed. ...
sophit's user avatar
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5 votes

What are the correct Cd0 and Cdi values for a NACA 2412 airfoil?

Answering the question: Why are induced and parasite drag equal at best L/D? It is easy enough to do the math... Starting with a simple parabolic polar $C_D=C_{D,0}+K\,{C_L}^2$ Divide both sides by $...
Rob McDonald's user avatar
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2 votes

What are the correct Cd0 and Cdi values for a NACA 2412 airfoil?

Is it possible the mathematical modeling is overestimating Cdi? Maybe they used the wrong data! For the answer, below, a simple approach is taken that converges on the desired result. In completing ...
Thomas Perry's user avatar
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3 votes

What are the correct Cd0 and Cdi values for a NACA 2412 airfoil?

An airfoil does not have $c_{d,i}$. Induced drag is a 3D effect. An airfoil is a 2D entity. When you look at airfoil drag data in a book, the non-constant value (that sometimes looks like a parabola)...
Rob McDonald's user avatar
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1 vote

Computing the eigenvalues of the longitudinal dynamics _analytically_: is there a method to simplify the task, or must it be brute force?

are they telling to express the eigenvalues algebraically in terms of the entries of the general matrix of longitudinal dynamics? The way I read the problem yes they are. Although I'm not familiar ...
Daniel K's user avatar
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1 vote

How/why does engine torque and horsepower affect aircraft speed?

Horsepower and torque affects RPM. For a given torque, an aircraft needs greater RPM to achieve greater speed. And that means more horsepower. For a given RPM, an aircraft with a higher blade pitch ...
Abdullah is not an Amalekite's user avatar
0 votes

How/why does engine torque and horsepower affect aircraft speed?

Perhaps, in context, this example may be helpful. We have, say, a piston engine turning a propeller sufficiently to produce enough thrust from that propeller to maintain an aircraft in flight. ...
Thomas Perry's user avatar
  • 1,192
0 votes

How/why does engine torque and horsepower affect aircraft speed?

Horsepower is a measure of the total power output, this is proportional to RPM multiplied by torque. How this relates to static thrust depends on the diameter and pitch of the propeller; a bigger ...
Frog's user avatar
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