Definition
An unintended low-resistance electrical path that allows current to bypass the normal load and flow directly between two points in a circuit, typically between a hot conductor and ground or between conductors of opposite polarity. Because the resistance is very low, current flow becomes very high, which can blow fuses, trip circuit breakers, overheat wiring, and start fires.
Plain English
When electricity finds an accidental shortcut and skips the equipment it was supposed to power, current shoots up dangerously and something usually melts, trips, or burns.
Context Anchor
Seen in aircraft electrical system discussions, maintenance write-ups, abnormal procedures, and troubleshooting after a breaker trips or equipment stops working.
Derivation
The word 'short' here means 'shortened path,' not 'small.' Current takes a shorter route than the designer intended, skipping the load. Knowing this prevents the common assumption that a short circuit is just a 'minor' or 'small' electrical problem.
Why Pilots Care
Can lead to overheating, fires, or failure of critical electrical systems in flight.
Analogy
Think of water meant to flow through a hose nozzle, but a hole opens in the hose before the nozzle. The water takes the easier path through the hole instead of doing the job it was supposed to do.
Intuition Check
“Short” does not mean the circuit is physically small. Here it means electricity is taking an unintended easier path, often with too much flow.
Example Sentence 1
After the landing light breaker popped twice in a row, the pilot suspected a short circuit in the wiring and left the breaker out for the rest of the flight.
Example Sentence 2
During preflight, a short circuit in the avionics bus can drain the battery quickly.