FAA Private Pilot Helicopter (PRH)Performance and LimitationsEasy
A helicopter's hover ceiling out-of-ground-effect (OGE) is always
- Aunrelated to ground effect
- Blower than its IGE hover ceiling
- Cthe same as its IGE hover ceiling
- Dhigher than its in-ground-effect (IGE) hover ceiling
Show answer & explanationAnswer & explanation
Correct answer: B. lower than its IGE hover ceiling
Ground effect reduces induced drag and increases rotor efficiency near the surface, allowing a higher hover ceiling IGE. Without ground effect, more power is required for the same performance, so the OGE hover ceiling is always lower.
Why the other options are wrong
- A. Ground effect is directly related to hover ceiling performance.
- C. Ground effect provides a measurable performance benefit, so they are not equal.
- D. This reverses the actual relationship between IGE and OGE performance.
Hover Ceiling IGE vs OGE
Maximum density altitude at which a helicopter can hover, either in ground effect (IGE) or out of ground effect (OGE); OGE is always lower due to increased power requirements.
- Ground effect reduces induced flow and power required
- IGE hover ceiling is typically higher than OGE
- OGE hover is used for performance planning at high density altitude sites
Memory trick: Ground gives a boost — lose it, lose altitude.