When does the landing gear warning horn sound normally?

The landing gear warning horn typically sounds when the power levers are retarded below a specific threshold, usually between 79-82% N1, while the landing gear and flaps are in the up position. This warning serves as a safety mechanism to alert the pilot that the aircraft could be approaching an unsafe flight configuration; specifically, it helps prevent inadvertent gear retraction or prevents flying at an unsafe speed with the landing gear up while the engines are not producing enough thrust.

In this context, the presence of the gear warning horn under these conditions emphasizes the importance of maintaining awareness of the aircraft's configuration and ensuring that the landing gear is correctly deployed during critical phases of flight, such as descent or approach for landing.

In contrast, the other options do not accurately describe the conditions under which the landing gear warning horn would activate. For instance, if the gear is deployed, the warning horn should not sound, as the aircraft is in a safe configuration for landing. Similarly, the horn does not sound when the gear is extended at high speed, as the gear is only meant to be deployed safely within specific parameters. The warning also should not activate simply due to initiating gear retraction, as the conditions specify power lever settings that relate directly to flight