Go-around
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A go-around is an aborted landing of an aircraft which is on final approach.
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[edit] Origin of the term
The term arises from the traditional use of circuits at airfields — a landing aircraft will first join the circuit pattern and prepare for landing in an orderly fashion. If for some reason the pilot decides not to land, he can simply fly back up to circuit height, and complete another circuit — in other words, go around again. The term go-around is still used even for modern airliners, though they may not use traditional circuit patterns for landing.
[edit] Reasons for going around
The go-around procedure may be initiated either by the air traffic control (normally the local or 'tower' controller in a controlled field) or by the pilot in command of the aircraft.
In a controlled field, the local controller may instruct the pilot to go around if there is an aircraft, vehicle or object on the runway or some other unsafe condition. In both controlled and uncontrolled fields, the pilot in command may decide to go around at any time, for example if the aircraft is not lined up or configured properly for a safe landing; an aircraft, vehicle or other object has not cleared the runway; no landing clearance was received (in a controlled field); the landing gear is not properly extended; a dangerous meteorological condition is experienced on final approach (e.g. poor visibility, excessive cross-winds, etc.); or some other unsafe condition is detected.
A go-around does not in itself constitute any sort of emergency (although it may on rare occasions be in response to an emergency). A properly executed go-around is a routine, safe and well-practiced maneuver. Nevertheless, a go-around may cause passengers to become anxious, and if a second go-around is performed many airline policies advise pilots at that point to divert to another airport, rather than attempt landing a third time.
Flights conducted under instrument flight rules, including all airline traffic, refer to "executing the missed approach" rather than going around. The maneuver itself is the same, but the pilot instead follows a pre-defined navigational "missed approach" sequence, published on the approach chart, instead of entering a circuit or pattern. Absent further instructions from the controller, a missed approach sequence directs an aircraft around traffic patterns and terrain into a safe place to begin a holding pattern.
[edit] The go-around procedure
When the pilot is instructed, or decides him/herself to go around, s/he will apply full power to the engine(s), adopt an appropriate climb attitude and airspeed, retract landing gear, retract flaps as necessary, follow the instructions of the air traffic controller (in a controlled field) and typically climb into the traffic pattern for another circuit if required.
Many modern aircraft such as the Airbus series use fly-by-wire systems with go-around modes that automatically set maximum available power and pitch the aircraft for best performance. On other aircraft, the pilot performs the go-around manually. In a typical small aircraft, such as those found in general aviation, this might involve:
- applying full power
- adopting an appropriate climb attitude and airspeed
- removing one stage of flap if necessary
- checking for a positive rate of climb
- raising the landing gear, if the aircraft has retractable gear
- raising the flaps fully once a positive rate of climb is established and the aircraft is above a certain safe altitude
- removing carburetor heat, if on
- climbing back to pattern altitude
- advising control tower and/or other traffic about go around decision by radio
This is easily remembered by the mnemonic "5C's" -- Cram it, Climb it, Clean it up, Cool it, and Call it!, or sometimes the "5 Ups": Power Up, Nose Up, Gear Up, Flaps Up, Speak Up.
