The ETOPS 60-minute range for flight planning is based on which condition?

The correct answer is based on the condition of single engine inoperative. The ETOPS (Extended-range Twin-engine Operational Performance Standards) requirements ensure that twin-engine aircraft can safely operate on extended routes that are far from a diversion airport. The 60-minute range indicates the maximum distance an aircraft can fly from an adequate airport while experiencing a single engine failure.

In this context, if an aircraft were to lose an engine, it still needs to be able to maintain controlled flight. This 60-minute benchmark is critical as it allows operators to plan routes that provide reasonable access to an alternate airport within that timeframe in the event of engine failure. The performance and capability of the aircraft when operating with one engine inoperative play a crucial role in these calculations and regulations.

This safety requirement is designed to ensure that the aircraft can maintain safe operational limits and reach an airport for landing within a safe timeframe, considering the reduced power and performance. As such, flight planning based on the ETOPS 60-minute range emphasizes the importance of having a reliable aircraft performance standard.