Within what percentage of the runway must you stop?

• A. 50%
• B. 60%
• C. 70%
• D. 80%

Answer: (B)

The key idea is planning your stop distance with a built‑in safety margin on the runway. Stopping within sixty percent of the runway gives you a practical balance: you have enough distance to stop reliably under various conditions (braking action, weight, wind, runway surface) while not consuming so much of the runway that any small error or unexpected condition could leave you with insufficient remaining distance.

If you had to stop within only half of the runway, any drop in braking efficiency or adverse conditions could push you past the available length. On the other hand, aiming to stop within seventy or eighty percent of the runway would demand more stopping distance than is typically safe or guaranteed under all conditions, reducing margins for errors. So sixty percent is the choice that best preserves safety while keeping stopping requirements achievable.