An arc fault is a high power discharge of electricity between two or more conductors.
This discharge generates heat, which can break down the wire's insulation and trigger an electrical fire.
In contrast, arc fault circuit breakers use magnetic or other means to detect increases in current draw much more quickly.
For instance, lightning strikes on the outside of an aircraft mimic arc faults in their voltage and current profiles.
Research has been able to largely eliminate such false positives, however, providing the ability to quickly identify and locate repairs that need to be done.