FAA Private Pilot Helicopter (PRH)Performance and LimitationsHard
A helicopter's flight manual lists a structural maximum gross weight of 3,000 pounds. Performance charts for the current density altitude and temperature show that the maximum weight for an OGE hover is only 2,700 pounds. Which weight limit applies to this flight if an OGE hover is required?
- ANeither limit applies since OGE hover is optional
- B2,850 lb, the average of the two limits
- C3,000 lb, since the structural limit always takes precedence
- D2,700 lb, since the more restrictive performance limit governs the operation
Show answer & explanationAnswer & explanation
Correct answer: D. 2,700 lb, since the more restrictive performance limit governs the operation
When a performance-based limit (such as maximum weight for an OGE hover) is more restrictive than the structural maximum gross weight, the more restrictive limit governs the operation. In this case 2,700 lb is the limiting weight for a safe OGE hover, even though the aircraft is structurally certified to 3,000 lb.
Why the other options are wrong
- A. If an OGE hover is required for the mission, the performance limit must still be respected.
- B. Averaging limits is not a valid method of determining operating limitations.
- C. Incorrect; the structural limit is not the sole governing factor when performance is more restrictive.
Structural vs Performance-Limited Weight
The maximum operating weight for a given flight is the lesser of the structural maximum gross weight and any performance-limited weight (such as for hover, takeoff, or climb) under existing conditions.
- Structural limit is fixed by the manufacturer
- Performance limits vary with density altitude, wind, and temperature
- The more restrictive limit always governs the flight
Memory trick: The lowest fence wins — always obey the tighter limit.