What is the appropriate airspeed to use when climbing with one engine inoperative, without obstacles?

The appropriate airspeed to use when climbing with one engine inoperative is VYSE, also known as the "Blue Line" speed. This speed is specifically designed for situations where an aircraft is operating with one engine out, allowing for the best rate of climb. At VYSE, the aircraft achieves the ideal balance of power and drag, maximizing altitude gain over time under these less-than-ideal conditions.

VYSE is critical because it provides a safety margin during single-engine operations, ensuring that the aircraft maintains positive control and sufficient lift, which is crucial for avoiding stalls during climbs. This performance is significantly important in multi-engine aircraft, where the failure of one engine can greatly affect climb capabilities.

In contrast, options like VX (best angle of climb) and VYZ (a lesser-known term that may refer to another airspeed related to climb performance) do not apply in this specific scenario. VX is focused on achieving the highest altitude over the shortest horizontal distance, which is not the goal when dealing with an engine failure. VNE represents the maximum speed for safe operation, beyond which structural integrity could be compromised, making it unsuitable for climbing conditions at all.

Choosing VYSE ensures that pilots maintain safety while optimizing climb performance even when faced