Forum: aviation.stackexchange.com
Tags: <propeller><fixed-wing><rotary-wing>
Title: Is a propeller a wing?
Question: An aviation expert claimed to me that a propeller is a wing.  While I understand that propellers use similar principles to generate force, it muddied the definition of a rotary wing aircraft vs a fixed wing aircraft.  If the propeller of a fixed wing aircraft is considered a wing, what is the distinction between the two?  Is it how much surface area each type of wing works on?  Is it the direction of force?

Answers:
sents: text: I think most people would say the answer is no .
text: Consider the dictionary.com definition as it relates to Aeronautics: 9.
text: Aeronautics .
text: a. one of a pair of airfoils attached transversely to the fuselage of an aircraft and providing lift.
text: b.
text: both airfoils, taken collectively.
text: The wings are the big airfoils which are responsible for generating most of the vertical lift.
text: A colloquial test of this definition would be to grab a CFI and ask him/her to "point out the wings on this airplane to me.
text: " They won't point out the propeller.
text: ( Not a scientific experiment )
text: However, both wings and propellers are airfoils (and so are the other wing-like surfaces such as the vertical and horizontal stabilizers).
text: You might get some disagreement about whether those other surfaces are wings, but I believe the answer is still no.
text: There is nothing to be gained by calling them wings, and only leads to ambiguity.
text: We already have a word which describes lifting surfaces in-general, and again, it's airfoil .
answer_details: author: aviation.stackexchange.com/users/6/Bret Copeland
score: 17
sents: text: Is a propeller a wing?
text: Maybe.
text: It depends on how pedantic you feel like being about your definitions.
text: A propeller is certainly an airfoil (usually several of them - each blade is an airfoil, and you can have one blade , two, three, four, or more attached to a hub).
text: A wing is also an airfoil.
text: Aerodynamically a wing and a propeller function the same way:
text: Air moves over the surface of the airfoil(s), producing "lift".
text: In the case of the wing the lift is mainly vertical and we call it "lift", while in the case of a propeller it's mainly horizontal and we call the resulting force "thrust" instead.
text: My two cents, ignoring all the dictionary pedantry?
text: A propeller is an airfoil, but it is not a wing.
text: Why?
text: Simple: If I'm flying along and my propeller magically vanishes I'm now flying a really inefficient glider.
text: My day is ruined and when I catch the guy with the genie-in-a-lamp who wished my propeller away I'll probably beat them up, but I have a fair chance of putting the aircraft on the ground without killing myself or anyone else.
text: If I'm flying along and my right wing magically vanishes the genie-posessing miscreant is safe as I'm almost certainly going to die.
text: All the lift from the remaining wing is going to try to flip the aircraft over, and I'm nowhere near skilled enough to keep control with a missing wing and land safely .
answer_details: author: aviation.stackexchange.com/users/64/voretaq7
score: 12
sents: text: An aviation expert reminded me that a propeller is a wing.
text: This is not false- a wing generates lift by creating a pressure difference, in the same way a propeller does.
text: Wing typically refers to the structure lifting the main weight of the aircraft, while a propeller generates thrust, so from definition it's probably incorrect, from a theoretical standpoint
text: it's the same principle.
text: While I understand that propellers use similar principles to generate force, it muddied the definition of a rotary wing aircraft vs a fixed wing aircraft.
text: A fixed wing aircraft will move at speed to generate sufficient lift to get airborne.
text: A helicopter will be able to lift off vertically by spinning the blades quickly enough, which will have the same effect as moving forward.
text: If the propeller of a fixed wing aircraft is considered a wing, what is the distinction between the two?
text: Is it how much surface area
text: each type of wing works on?
text: Is it the direction of force?
text: Propeller thrust is directed forwards.
text: In level flight it contributes very little to lifting the plane up-
text: that's left to the wings to do.
text: Rotary wing aircraft's blades do really work as a propeller: By increasing the angle of attack on one side, you generate more thrust, and the helicopter flies in the direction you want it to, since there's a force vector in that direction.
text: (source: tiscali.co.uk )
text: Distinction between the two: Rotorcraft generate the thrust to lift off themselves.
text: A propeller generates the thrust (and in turn speed) necessary to create lift over fixed surfaces.
answer_details: author: aviation.stackexchange.com/users/790/Thunderstrike
score: 8
sents: text: Since no one else mentioned this, I thought I would.
text: Wilbur Wright, of the Wright brothers, said that a propeller was nothing more than a twisted wing.
text: If you accept his analogy, then the twisted wings that compose a propeller are clearly specialized wings, but they do generate a differential in air pressure above/in front of and below/behind as the surface moves through the air.
text: That is what a wing does.
answer_details: author: aviation.stackexchange.com/users/1674/Greg Conquest
score: 3
sents: text: When one thinks with respect to plane, things are a lot less "muddy".
text: Forget about definitions and rote and focus on what the function is.
text: First, while airborne, the only thing with respect to ground is gravity.
text: Everything else is dependent on orientation of the aircraft.
text: This is not muddy, it is actually a crucial step in becoming a better pilot.
text: So, starting with straight and level flight, it is obvious what is the wing (lift) and what is the propeller (thrust).
text: Now pitch up, add power and climb.
text: Yes, the propeller is now helping you climb as well as maintaining airspeed.
text: Is it now called a wing?
text: No, it is still out in front of the plane, so, with respect to plane, it is still the propeller!
text: The key is to draw the thrust vector, then break it down to vertical and horizontal components.
text: The propeller is helping lift the plane.
text: Now rotary wing aircraft.
text: All lift is provided by spinning the rotor, and forward motion too!
text: So it is both wing and propeller.
text: Birds have learned this trick as well!
text: So do not worry about muddy, take what you need and fly.
answer_details: author: aviation.stackexchange.com/users/32094/Robert DiGiovanni
score: 1

Summary of the answers:
 A propeller and a wing are certainly airfoils.
It depends on the definition, as a wing and a propeller are both certainly airfoils. However most people would say no it is not.