Which CL1 type of fluid leak will cause a Vehicle to be Non-Mission Capable (NMC)?

• A. Any Fuel Leak
• B. Any Oil Leak
• C. Any Coolant Leak
• D. Any Hydraulic Leak

Answer: (A)

Fuel is essential for propulsion and overall aircraft safety. A fuel leak is inherently dangerous because it can quickly lead to a fire hazard and fuel exhaustion, both of which can completely prevent safe flight or operation. In CL1 classifications, anything that threatens propulsion or the immediate safety of the aircraft is deemed non-mission capable, so even a small fuel leak triggers that status because you cannot guarantee safe continued operation or mission completion.

Oil, coolant, and hydraulic leaks are serious and require maintenance, but they don’t universally render the aircraft unable to perform a mission by themselves. Their acceptability depends on factors like leak rate, location, and system redundancy, whereas a fuel leak by its nature directly compromises flight safety and mission viability.