Talk:Airfoil

message: The "Lift and drag curves for a typical airfoil" is a meaningless chart since it does not mention the Reynolds Number.  It also looks dramatically wrong - real lift and drag coefficients never look like that.  Someone should insert a real chart in place.  — Preceding unsigned comment added by 2001:8000:1BED:6D00:C2D:7209:A7E7:3834 (talk) 10:51, 24 May 2020 (UTC)
replies: text: The chart is an aid to understanding the twin concepts of lift coefficient and drag coefficient; and their relationship with the angle of attack. It is supplied to help readers who are new to the subject. The chart is not intended to be a scientific document to be used by aerodynamicists and aircraft engineers in the design of an actual aircraft. If the chart showed Reynolds Number and Mach Number, as well as angle of attack, it would not be appropriate in this article so we would have to find an alternative, more appropriate diagram. This principle is well explained at Wikipedia:Make technical articles understandable. Dolphin (t) 11:56, 24 May 2020 (UTC)
thread_title:  Missing Re on the last diagram 

message: Airfoil doesn't seem to discuss laminar flow airfoils. Will (Talk - contribs) 10:39, 5 June 2020 (UTC)
thread_title:  Why does [[laminar flow airfoil]] redirect here? 

message: I accidentally stumbled onto a resource that might have some value as an encyclopedic resource of airfoil information from the past.
It mentions another resource as well that may be worth a look.
I do not plan to edit here but leave this as a drive by link drop for idle hands to do what they want.
https://m-selig.ae.illinois.edu/ads/aircraft.html
Idyllic press (talk) 19:44, 21 March 2021 (UTC)
thread_title:  Potential resource 

message: The current version of the article begins with a definition of an airfoil (or aerofoil), saying it is "...the cross-sectional shape of an object ..." By defining an airfoil as a cross-sectional shape, Wikipedia is saying it is a two-dimensional figure.
Paradoxically, elsewhere in the article is the clear implication that an airfoil is not simply a two-dimensional figure because it is stated that airfoils generate lift. (A two-dimensional figure has a planform area of zero because it has thickness of zero, and therefore regardless of the pressure difference on the two sides of the figure there will be no force generated.) Consider the following expressions taken from the lead:
:"resulting in a force on the airfoil in the opposite direction to the deflection."
:"An airfoil is a streamlined shape that is capable of generating significantly more lift than drag."
:"The lift on an airfoil is primarily the result of its angle of attack."
:"... cambered airfoils can generate lift at zero angle of attack.
These four examples show that Wikipedia considers airfoils as devices that can generate lift, and therefore are three-dimensional. The sole inconsistency is in the first sentence which defines an airfoil as a "cross-sectional shape".
I will attempt to eliminate this inconsistency by adjusting the definition of an airfoil to include all bodies that are capable of generating significantly more lift than drag. As a result, it will be reasonable for Wikipedia to state, or imply, that wings, propeller blades, rotor blades and stabilizers are all examples of airfoils. 
Here is the definition I intend to insert into the first sentence of the lead:
:"An airfoil (American English) or aerofoil (British English) is a streamlined body that is capable of generating significantly more lift than drag. Wings, sails and propeller blades are examples of airfoils."
The two-dimensional cross-sectional shape of typical airfoils should hereafter be described as "airfoil sections". Dolphin (t) 11:54, 28 April 2023 (UTC)
thread_title:  Definition of an airfoil 

message: When were aerofoils applied to flight? Was there a development path from ancient times or was the principle discovered in the 20th century? Humphrey Tribble (talk) 13:14, 21 August 2023 (UTC)
replies: text: If we accept the idea that the wings of birds and other flying creatures are aerofoils, we must accept that aerofoils have been operating almost since the beginning of geological time. However, one idea is that aerofoils are man-made devices that must qualify under fairly strict criteria, then the first aerofoil was likely seen in the wing of the glider designed and built by George Cayley in the first decade of the nineteenth century. See George Cayley#Flying machines. The strict criteria I am referring to include the requirement that an aerofoil must be able to develop significantly greater lift than drag. Dolphin (t) 13:45, 21 August 2023 (UTC)
thread_title:  No history?