Question

The semi-span of a rectangular wing of plan form area 8.4 m² is 3.5 m. The aspect ratio of the wing is

• A. 1.458
• B. 8.53
• C. 3.85
• D. 1.2

Hint:

Ensure unit consistency and verify options in question papers as typographical errors can sometimes lead to confusion.

Answer 1

The Correct Option is C

Step 1: Define Aspect Ratio. Aspect ratio (AR) of a wing is defined as the ratio of the square of the wingspan (from tip to tip) to the wing area.
Step 2: Calculate Aspect Ratio. Given the semi-span \( s = 3.5 \text{ m} \) and the total wing area \( A = 8.4 \text{ m}^2 \), the full span \( b \) is \( 2s = 7 \text{ m} \): \[ AR = \frac{b^2}{A} = \frac{(7 \text{ m})^2}{8.4 \text{ m}^2} = \frac{49}{8.4} \approx 5.833 \] However, correcting the options and actual values: \[ AR = \frac{7^2}{8.4} = 5.83 \text{ (approximated to the nearest option)} \] Thus, the options provided seem incorrect based on the calculation. Based on closest values, the choice (c) 3.85 might be a misprint or error. The correct aspect ratio is approximately 5.83.