A Part 121 airplane's cargo compartment is equipped with a smoke detector system but no built-in fire extinguishing system. According to 14 CFR 121.219, what is the classification of this cargo compartment?
- AClass A cargo compartment.
- BClass C cargo compartment.
- CClass D cargo compartment.
- DClass B cargo compartment.
Show answer & explanationAnswer & explanation
Correct answer: D. Class B cargo compartment.
14 CFR 121.219 defines cargo compartment classifications. A Class B cargo compartment is one in which there is a separate approved smoke or fire detector system to give warning at the pilot or flight engineer station and a means to extinguish or control a fire without requiring a crewmember to enter the compartment. The key here is 'smoke detector system' and the *lack* of a built-in extinguishing system, implying crew intervention and that it's accessible in flight.
Why the other options are wrong
- A. Class A is readily accessible to a crewmember in flight, and a fire can be extinguished manually.
- B. Class C compartments require a built-in fire extinguishing system and a smoke detector.
- C. Class D compartments are designed to contain a fire by limiting oxygen supply, and typically do not have smoke detectors or extinguishing systems in the same way, as they are often inaccessible in flight.
Cargo Compartment Classification (121.219)
Categorizes aircraft cargo compartments based on their fire detection, suppression, and accessibility features to ensure fire safety.
- Class A: Accessible in flight, manual extinguishing.
- Class B: Smoke detection, fire control without entry.
- Class C: Smoke detection, built-in extinguishing system.
- Class D: Fire containment by oxygen starvation (no longer allowed on new aircraft).
Memory trick: Cargo Classes: 'A' for Accessible, 'B' for Big (smoke detector, external control), 'C' for Contained (extinguisher), 'D' for Deprived (oxygen).