What is unique about the holding speed?

• A. It is minimum drag
• B. It is maximum endurance
• C. It is maximum speed
• D. It is equal to Vref

Answer: (A)

Holding speed is chosen at the speed where drag is minimized for the aircraft in level flight. At this speed the total drag is at its lowest because induced drag (which dominates at slow speeds) and parasite drag (which grows at higher speeds) balance out. Minimizing drag means you need the least thrust to stay aloft, which in turn minimizes fuel flow and maximizes endurance in the hold. That’s why this speed is described as the unique holding speed. If you flew faster or slower, drag and fuel burn would rise, reducing efficiency. The other options don’t match what’s special about holding speed: a maximum speed would waste fuel, Vref is a landing reference speed not the holding speed, and while endurance relates to fuel efficiency, the defining trait of holding speed is its minimum drag.