Question

NACA 2412 airfoil has

• A. 4% maximum camber with respect to chord
• B. maximum camber at 40% chord
• C. 12% maximum thickness to chord ratio
• D. maximum camber at 20% chord

Hint:

To decode NACA 4-digit airfoils, remember: 1st digit = max camber %, 2nd = location of max camber ×10, last two = thickness % of chord.

Answer 1

The Correct Option is B, C

Step 1: Understanding NACA 4-digit series.
NACA 2412 is a 4-digit airfoil. Each digit gives specific geometric properties:
- The first digit (2) represents the maximum camber as a percentage of chord: \(2%\).
- The second digit (4) indicates the position of maximum camber from the leading edge in tenths of chord: \(0.4c\) or 40%.
- The last two digits (12) represent the maximum thickness to chord ratio: \(12%\).
Step 2: Evaluate all options.
(A) Incorrect: Camber is 2%, not 4%.
(B) Correct: Maximum camber is located at 40% of the chord.
(C) Correct: The airfoil has 12% thickness-to-chord ratio.
(D) Incorrect: Maximum camber is at 40% chord, not 20%.