FAA Sport Pilot Airplane (SPA)Aircraft Performance and SystemsHard
A pilot notes that at a certain altitude, the airplane's maximum rate of climb has decreased to only 100 feet per minute. This altitude best represents which performance limit?
- ACritical altitude
- BDensity altitude limit
- CService ceiling
- DAbsolute ceiling
Show answer & explanationAnswer & explanation
Correct answer: C. Service ceiling
Service ceiling is defined as the altitude at which the airplane's maximum rate of climb decreases to 100 feet per minute. Absolute ceiling is the altitude at which climb rate reaches zero.
Why the other options are wrong
- A. Critical altitude applies to turbocharged engines maintaining rated power, unrelated to climb rate.
- B. Density altitude limit is not a standard performance term for ceilings.
- D. Absolute ceiling occurs where climb rate reaches zero, not 100 fpm.
Service Ceiling
The maximum density altitude at which an airplane can still achieve a 100 feet-per-minute rate of climb.
- Defined by 100 fpm climb rate, not zero climb
- Absolute ceiling is where climb rate = 0 fpm
- Both ceilings decrease with increased weight or reduced power
Memory trick: Service ceiling: still serving 100 feet a minute.