Wings = Fan Blades? Aeroscience Question.

[oromis]

I was trying an interesting riddle today, and it didn't turn out as planned, because somebody thought Fan Blades and Wings of an airplane were too different to be called synonyms.

Where I'm coming from:
Wings split the air so that it creates pressure, pushing air below it, keeping the airplane up. Helicopter blades do that same exact thing, correct? They spin, that movement splits the air and pushes it downward, causing lift. I then related that to a fan. Am I correct when I say fans create lift? They push air the same way a helicopter blade and wing do, correct? It's just on a different axis, right?

He says:
Helicopters don't create the same lift that airplane wings do, and fans are a different thing entirely because they don't create lift. Wings keep planes up, fans give us a breeze, therefore they are different things.

Can somebody clarify, and maybe post some official information in case he asks for a source or something similar?

[Ad Bot]

[Menen]

Wings =/= Propellers.

Propellers provide lift. Wings stablize the plane.

[aml]

Fans just don't go as fast as a helicopter blade, therefore they get little to no lift.
They are basically the same though.

[oromis]

Propellers provide lift.

wings provide lift too

[Jubel]

Wings be trollin your head.

[Tom]

Propellers provide thrust. They do not create lift.

[Titanium]

In order to answer this question, it is important to understand what is meant by the term "thrust" or by "lift."

Thrust - When a mass exerts force in a given direction, that force will propel the mass in a proportional but opposite direction.  I.e., the blades of a turboprop/turbojet engine.  A turboprop/turbojet engine can produce thrust because the internal mechanisms of the engine drive the prop/fan which sucks air in and and forces it back out, propelling the engine with proportional force, but in the opposite direction.  It cannot generate lift because it is not a mass through which a gradient of air flows creating areas of higher or lower pressure to which the mass is forced.

For example:  An engine flying through the air at full power with unlimited fuel on its own with no other mass or control surfaces connected to it will never fly upwards or sink downwards unless acted upon by another force.  It will simply fly in a straight line (without taking gravity into consideration).

Lift - When a mass deflects air in a manner so that the air flows around the mass, forcing it up or downwards.   I.e., a wing.  Wings generate lift because they are a solid surface over/under which air flows.  Most wings, when viewed from the side, are angled slightly upwards in order to create areas of high pressure on the bottom and low pressure on the top.  When inside a stream of air, wings will naturally be forced upwards toward the area of lower pressure.  It cannot generate thrust because it is a solid surface without the means to push or pull the air, but rather reacts to it indiscriminately.

For example: A wing flying through the air by itself without any other mass or control surfaces connected to it will stay in flight until gravity and lack of continuous thrust cause it to stall and fall back to Earth.  This is how a glider works.  Its wide wings create a cushion of air underneath which pushes the glider upwards against the force of gravity.  Since it has no engines, it cannot maintain constant climb and therefore must eventually land.

tl;dr - Look at the picture.

[Tom]

Nice copypasta.

[General Nick]

The wings make the air above the wing travel a slightly longer distance thus reducing pressure. When the plane gets to very high speeds at take off, the low pressure above the wing is so great that it helps the plane lift up, especially when the flaps are used on the wings too.

The propellers on a helicopter don't do the same really. More or less they operate like a regular air fan except they are positioned so that the "fan" of a helicopter pushes air down at a high and constant rate. That is why helicopters often kick up dust when landing on dirt or water in the ocean.

[Titanium]

Nice copypasta.

Search any of those sentences.  Yes, I read up on the material, but I wrote it.

[A.R.C.]

The answer is magnets.