What indicates a successful interception of the VNAV glide path?

A successful interception of the VNAV glide path is indicated by smooth transitions between altitude levels according to VNAV guidance. This reflects the aircraft following the predefined vertical profile established for the flight, resulting in gradual and controlled altitude changes that align with the VNAV path. A smooth transition suggests that the autopilot or flight management system is effectively managing the descent, adjusting as necessary to stay on the glide path.

The other choices, while potentially relevant to overall flight performance, do not directly signify successful interception of the glide path. For instance, a steady descent rate without adjustments may not indicate proper following of the glide path, as it could suggest a rigid flight profile that does not account for necessary adjustments based on VNAV guidance. Continuous altitude alerts could indicate that the aircraft is not maintaining the desired path, which would be a sign of an issue rather than a successful interception. Finally, maintaining the same speed throughout a descent does not contribute to a successful interception, as the VNAV system may require adjustments in airspeed to adhere to the vertical profile correctly. Therefore, smooth transitions are the key indicator of properly following the VNAV glide path.