What is the stated requirement for anti-collision lights at night?

• A. Anti-collision lights must be on at all times
• B. Anti-collision lights are required only during flight in good weather
• C. Anti-collision lights must be on unless unsafe (on ground in clouds)
• D. Anti-collision lights are never required at night

Answer: (C)

Anti-collision lights are there to make your aircraft more visible to others, especially at night when it’s harder to spot airplanes against the background. The stated rule is that these lights must be on during night operations unless turning them on would create an unsafe situation. That means the default expectation is illumination to improve conspicuity, but an explicit safety exception allows turning them off if keeping them on would be unsafe. The other ideas aren’t correct because lights aren’t limited to good weather, they aren’t never required at night, and they aren’t mandated to be on all the time without exception.