Question

Which of the following is correct?

(a) Ground roll = 0.5 * \(\int_{Vi}^{Vf}(\frac{1}{a})dV^2\)

(b) Ground roll = \(\int_{Vi}^{Vf}(\frac{1}{a})dV^2\)

(c) Ground roll = 0.5 / \(\int_{Vi}^{Vf}(\frac{1}{a})dV^2\)

(d) Ground roll = \(\int_{Vi}^{Vf}dV^2\)

I have been asked this question in an interview.

The query is from Flight Mechanics in section Performance and Flight Mechanics of Aircraft Design

Answer 1

The correct option is (a) Ground roll = 0.5 * \(\int_{Vi}^{Vf}(\frac{1}{a})dV^2\)

To explain: A typical ground roll distance can be determined by using integration. If we integrate velocity divided by acceleration as shown by the above equation then, we can easily determine ground roll distance. Hence, ground roll distance is given by, Ground roll = 0.5 * \(\int_{Vi}^{Vf}(\frac{1}{a})dV^2\)  Where, V is velocity and a = acceleration.