FAA Private Pilot Helicopter (PRH)Performance and LimitationsHard
A hover ceiling OGE chart shows that at 0°C, the maximum gross weight for an OGE hover at 6,000 feet pressure altitude is 2,200 pounds. At 30°C, the maximum gross weight for an OGE hover at the same pressure altitude drops to 1,900 pounds. A pilot plans a departure at 6,000 feet pressure altitude with an outside air temperature of 30°C and an actual gross weight of 2,050 pounds. Based on this chart data, the pilot should conclude that:
- AAn OGE hover is possible at any weight since temperature does not affect hover ceiling
- BAn OGE hover is not possible because the current gross weight exceeds the 30°C limit of 1,900 pounds
- CAn OGE hover is possible because the weight is below the 0°C limit of 2,200 pounds
- DThe chart is invalid above 20°C and cannot be used for planning
Show answer & explanationAnswer & explanation
Correct answer: B. An OGE hover is not possible because the current gross weight exceeds the 30°C limit of 1,900 pounds
The pilot must use the chart value that corresponds to the actual conditions, which is 30°C at 6,000 feet, giving a maximum OGE hover weight of 1,900 pounds. Since the planned gross weight of 2,050 pounds exceeds this limit by 150 pounds, an OGE hover is not possible at these conditions; the 0°C data is irrelevant to this warmer-day flight.
Why the other options are wrong
- A. Temperature clearly affects the chart, reducing the max weight by 300 lb between 0°C and 30°C.
- C. The 0°C limit does not apply to a flight conducted at 30°C; using it would overestimate performance.
- D. The chart explicitly provides valid data at 30°C in this scenario.
Hover Ceiling Chart Interpolation
Hover ceiling performance charts vary with both pressure altitude and temperature; pilots must select the value matching actual conditions to determine maximum safe gross weight.
- Higher temperature reduces max hover gross weight at a given altitude
- Always use the temperature/altitude combination matching actual conditions
- Exceeding the chart's weight limit means the hover is not achievable
Memory trick: Match your real temperature to the chart—don't borrow a cooler day's numbers