The engine failure case for determining the basic runway length may require A. Only clearway B. Only stop way C. Either a clearway or a stop-way D. Either a clearway or a stop-way or both

The correct answer is: C. Either a clearway or a stop-way.

A clearway is a defined area beyond the end of a runway, intended to provide a safe area for an aircraft to land in the event of an engine failure. A stop-way is a defined area beyond the end of a runway, intended to provide a safe area for an aircraft to stop in the event of an engine failure.

The need for a clearway or stop-way depends on a number of factors, including the length of the runway, the type of aircraft, and the prevailing weather conditions. In some cases, both a clearway and a stop-way may be required.

The following is a brief explanation of each option:

• Option A: Only clearway. This option is incorrect because a clearway is not always required. In some cases, a stop-way may be sufficient.
• Option B: Only stop way. This option is incorrect because a stop-way is not always required. In some cases, a clearway may be sufficient.
• Option C: Either a clearway or a stop-way. This option is correct because a clearway or a stop-way may be required, depending on the specific circumstances.
• Option D: Either a clearway or a stop-way or both. This option is incorrect because a clearway and a stop-way are not always required. In some cases, only one of these may be required.