What does VNAV allow pilots to optimize during ascent?

VNAV, or Vertical Navigation, is a system used in aviation that allows pilots to manage and optimize their aircraft's vertical trajectory during a flight, particularly during ascent. By utilizing VNAV, pilots can establish and follow a vertical flight profile tailored for the specific aircraft and mission, which includes selecting the optimal climb rate and altitude during the ascent phase of flight.

This optimization helps enhance performance by ensuring that the aircraft climbs at an efficient rate that can save fuel, reduce engine wear, and improve overall flight safety. Determining the vertical profile for climb strategies takes into account factors such as weight, weather conditions, and airspace constraints, allowing for a calculated and efficient ascent trajectory.

The focus on vertical aspects of flight differentiates VNAV from horizontal navigation improvements or descent management. While those elements are relevant to flight operations, they do not specifically address the climb optimization that VNAV is designed to accomplish.