In terms of aircraft operations, what do aircraft arresting system lights indicate?

Aircraft arresting system lights are utilized primarily to indicate the distance remaining to the landing area, particularly in the context of arresting gear systems often found on aircraft carriers and certain runways designed for emergency landings. These lights provide critical information to pilots, helping them gauge their approach and landing distance, ensuring they can execute a successful landing or go-around if necessary.

This system enhances situational awareness for the pilot, allowing for timely adjustments during landing while providing feedback on the aircraft's relative position to the arrestor cable or landing zone. By illuminating as the aircraft approaches the designated landing point, these lights guide the pilot in accurately managing their descent, angle, and speed for a safe touchdown.

The other options pertain to unrelated aspects of aircraft operations, such as weather conditions, fuel levels, and runway surface conditions, which, while important for overall flight safety, are not indicated by arresting system lights. Instead, these factors are typically monitored through different instruments and systems specifically designed for those purposes.