Aero-Terms!

Aero-Terms are designed to be a daily reminder of the terms, names, acronyms and explanations of the unique language that populates the aviation world. Aerospace, sport aviation, fixed wing, helo, you name it... it's all fair game.

Aero-Terms should serve as a quick but intriguing reminder of the terms you may use every day, or an introduction to an aspects of the Aero-World you may not yet be familiar with. ANN also encourages readers to go beyond the FMI link, and further research any intriguing terms.

Suggestions for future Aero-Terms are ALWAYS welcome, as are additions or discussion of the explanations given for each Aero-Term.

Mean Aerodynamic Chord (MAC)

MAC stands for Mean Aerodynamic Chord. MAC is the chord through the centroid of a single wing's plan area. A wing's chord can be difficult to measure because only if a wing was completely rectangular is the MAC equal to the chord. Most wing's aerodynamic centers are at 25% MAC. The ratio of the chord of a wing to its span is known as the aspect ratio. Aspect ratio a relative indication of the lift-induced drag the wing might create. In general, planes with higher aspect ratios, as ones with wide, skinny wings, have less drag. This is why high efficiency gliders have such long wings.

FMI: www.faa.gov