Pilot-Initiated Go-Around

You may also decide to go around on your own initiative. This happens when you have visual contact with the runway but encounter an unsafe landing situation—crosswind stronger than expected, landing gear not indicating down, another aircraft in the landing zone, or an instrument failure. As the pilot in command, you have the authority to initiate a go-around at any time to preserve flight safety.
When you initiate a go-around, you must inform ATC immediately. Use the phrase "going around" to signal your action. If you can give a brief reason, do so, but do not delay the radio call waiting for perfect phraseology. Safety first.

Pilot-Initiated Go-Around

Brussels Tower · OE-LBA

PILOT: Brussels Tower, OE-LBA, on final, we have a gear indication issue, going around.
ATC OE-LBA, go-around APPROVED, climb to flight level two-zero-zero, turn left heading three-four-zero.
PILOT: Climb to flight level two-zero-zero, turn left heading three-four-zero, OE-LBA.