Which climb departure utilizes the least trip fuel?

The option that utilizes the least trip fuel is the best rate of climb. This climb profile optimizes the altitude gained per unit of time, allowing the aircraft to reach higher altitudes more efficiently in terms of fuel consumption. When climbing at the best rate of climb speed, the aircraft ascends at the maximum vertical speed, which minimizes the time spent in slower, less efficient ascent phases.

Efficiency in this context means less fuel burn over the trip because reaching cruising altitude faster allows for a quicker transition into a more fuel-efficient cruise mode. While other options have their respective benefits in terms of distance or obstacle clearance, they typically result in longer climb times, which can increase fuel consumption overall. Thus, the best rate of climb is specifically designed to balance performance and efficiency, making it the optimal choice for minimizing trip fuel consumption during a climb.