Linked Questions

48
votes
2answers
26k views

Why/when is the blunt nose better?

Most large aircraft and some fighters have blunt, rounded nose cone. OTOH many fighters (that don't use the nose for air intake) and notably the two supersonic airliners (Concorde, TU-144) have the ...
20
votes
3answers
27k views

Why and when to use flaps?

On a commercial airliner, what is the purpose of the flaps? I understand that depending on which direction they move in, they can be used to decrease airspeed, but I don't know when flaps are used. ...
22
votes
2answers
10k views

Why do Boeing and Airbus have distinctively different nose designs?

Boeing aircraft generally have a pointy nose, which seems to me to imply better aerodynamic qualities, less drag etc. Airbus aircraft on the other hand have rather bulbous noses. Is this difference ...
23
votes
2answers
3k views

Is a golf ball surface a good idea for wings or fuselage?

I searched for an infamous golf ball question on this site but did not find any, so I guess it's time for one. Would a dimpled surface like a golf ball somehow improve the aerodynamics of an airplane?...
10
votes
2answers
1k views

Why doesn't critical angle of attack increase with airspeed? [duplicate]

Critical angle of attack is related to the Coefficient of Lift, which is a function of Reynold's number. Reynold's number depends on the speed of the aircraft. So why doesn't the Critical Angle of ...
5
votes
5answers
3k views

Why are the leading edges of wings not always made as 'sharp' as possible?

Why is an airplane's wing (the leading edge) not made as sharp as possible to break the air, in the same way that a ship's hull is made sharp to easily break the water? This is unlike Concorde's nose ...
4
votes
4answers
1k views

Why does indicated stall speed change?

Aviation confusing me... I’ve read that stall speed doesn’t change (IAS) no matter what altitude you’re flying - of course under specific conditions ISA, 1G level flight, no wind, gross weight etc. ...
6
votes
1answer
2k views

How does compressibility affect the critical angle of attack?

Why does the critical angle of attack reduce with increasing mach number or What is the effect of compressibility on critical angle of attack?
5
votes
1answer
684 views

What's the theoretical background of the critical angle of attack?

The critical angle of attack seems to be at all (most?) airfoils around 15-20°. Why is that? Why is it in this range and not lower or higher? Is it just the result of optimizing airfoils? Or is it ...
4
votes
2answers
292 views

In this F-104 V-n diagram, why does the stall speed (in terms of IAS) decrease with altitude in some parts of the flight envelope?

(This question has been edited to reflect a change in perspective: based on answers to the related question What is causing these "corners" on this F-104 V-n diagram?, I now believe that the ...
5
votes
1answer
542 views

How do I obtain the max endurance altitude?

There are excellent explanations of the physics that determine maximum endurance speed here, here, and here. I was thinking of aircraft that have to be "on station" without an indicated altitude and ...
2
votes
1answer
398 views

Would adding a slat and a slotted flap increase the max CL of a multi element airfoil to 6.5?

Would adding a slat and a slotted flap increase the of a multi element foil to 6.5? I understand, as a general rule, the max $C_L$ for a classic NACA airfoil is as follows: Base: 1.5 Slat: + 0.7 ...
1
vote
1answer
163 views

Why is it harder to maintain laminar flow on larger aircraft?

I am told that on larger aircraft, suction will be needed to maintain laminar flow because of the larger leading edge radius. Why so? Is it because the air has to travel over a longer distance on the ...