Uploaded January 2014 | Updated September 2026, 2 weeks ago
The airfoil chord is a vital part of understanding the angle of attack of an airfoil, as well as other aerodynamic parameters in aircraft design. The definition of the chord line is straightforward, while the definition for the leading edge (LE)/trailing edge (TE) are a little more ambiguous.
"Second of All" Comment
The "first of all" comment (that I made in the video) was that the angle of attack actually changes based off of where you define the leading edge to be. The comment I forget to say in the video is that the chord length also changes based on the LE location. For the "minimum x value LE", the chord line is longer than the "minimum radius of curvature LE".
The airfoil chord is a vital part of understanding the angle of attack of an airfoil, as well as other aerodynamic parameters in aircraft design. The definition of the chord line is straightforward, while the definition for the leading edge (LE)/trailing edge (TE) are a little more ambiguous.
"Second of All" Comment
The "first of all" comment (that I made in the video) was that the angle of attack actually changes based off of where you define the leading edge to be. The comment I forget to say in the video is that the chord length also changes based on the LE location. For the "minimum x value LE", the chord line is longer than the "minimum radius of curvature LE".

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→ Detailed Afterburner Video
https://goo.gl/nt9KBp
REFERENCES
► Afterburners in The Aerothermodynamics of Aircraft Gas Turbine Engines, Zukoski
► Mechanics and Thermodynamics of Propulsion, Hill and Peterson
► Aerothermodynamics of Gas Turbine and Rocket Propulsion, Oates
► Aircraft Propulsion, Farokhi
► Aerospace Propulsion Systems, Ward
► Fundamentals of Jet Propulsion with Applications, Flack
THUMBNAIL PHOTO CREDIT
By United States Navy, Mass Communications Specialist 2nd Class Michael D. Cole [Public domain], via Wikimedia Commons In a Nutshell: Afterburners](https://i.ytimg.com/vi/EuITkZPd5c4/mqdefault.jpg)


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Chord Line: http://www.youtube.com/watch?v=Eh5W61iswSY Explained: Angle of Attack [Airplanes]](https://i.ytimg.com/vi/Fm2Az-PgPUU/mqdefault.jpg)




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https://goo.gl/50saau
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Photo Credit:
By NASA Glenn Research Center [Public domain], via Wikimedia Commons How To: Find Mach Number from a Picture (Part 2)](https://i.ytimg.com/vi/H25svaGf9-Y/mqdefault.jpg)