Missed approach is an instrument flight rules

Instrument flight rules

Instrument flight rules are one of two sets of regulations governing all aspects of civil aviation aircraft operations; the other are visual flight rules ....

 procedure which is a standard (but optional) component segment of an instrument approach

Instrument approach

For aircraft operating under instrument flight rules , an instrument approach or instrument approach procedure is a series of predetermined maneuvers for the orderly transfer of an aircraft under instrument flight conditions from the beginning of the initial approach to a landing, or to a point...

. Generally, if the pilot flying or the pilot in command determines by the time the aircraft is at the decision height (for a precision approach) or missed approach point

Missed approach point

Missed approach point is the "point prescribed in each instrument approach at which a missed approach procedure shall be executed if the required visual reference does not exist." It defines the point for precision and non-precision approaches when the missed approach segment of a flight begins...

 (for a non-precision approach), that the runway or its environment is not in sight, or that a safe landing cannot be accomplished for any reason, the landing approach must be discontinued and the missed approach procedure must be initiated immediately. It is also common for pilots to deliberately execute a missed approach as part of initial or recurrent instrument training. In such cases a pilot may execute three or four instrument approaches in a row with a missed approach between each one.

The missed approach procedure normally includes an initial heading or track and altitude to climb to, typically followed by holding instructions at a nearby navigation fix. The pilot is expected to inform ATC

Air traffic control

Air traffic control is a service provided by ground-based controllers who direct aircraft on the ground and in the air. The primary purpose of ATC systems worldwide is to separate aircraft to prevent collisions, to organize and expedite the flow of traffic, and to provide information and other...

by radio of the initiation of the missed approach as soon as possible.

ATC may simply acknowledge the missed approach call, or modify the missed approach instructions, for example with vectors to some other fix. ATC may subsequently clear the flight for another approach attempt, depending on the pilot's intentions, as well as weather and traffic considerations.