Stockholm-Arlanda Airport has 218,500 take-offs and landings per year. The number of full emergency alerts per year is about 25. The airport takes steps to heighten its readiness at the slightest indication that a landing is not normal.
Ordinarily it is the pilot who initiates a full emergency alert by contacting the air traffic control tower at the airport. The air traffic controllers then issue a full emergency alert, which means that the Rescue Service and affected parties at the airport are alerted. The Airport Fire Brigade moves to the affected runway and stands ready to act.
Pilots routinely tell air traffic controllers about malfunction indications in their aircraft, which may lead to a full emergency alert. An assessment of the situation is made on the basis of a situation list.
The situation list presents possible malfunctions and what decisions should be made. The alternatives are either to issue a full emergency alert or to let the commanding officer decide, i.e. leave it up to the pilot to determine whether a full emergency alert should be issued or not.
Once an aircraft has landed without incident, the rescue mission co-ordinator cancels the alert.
The municipal Rescue Service and the airport’s Fire Brigade respond to full emergency alerts.
The hospitals in the surrounding area heighten their readiness until the alert is cancelled.
Aircraft accident alert
When an incident affects an aircraft, it is referred to as an accident. The air traffic controllers in the tower issue an aircraft accident alert, which means that the Rescue Service and affected parties are alerted. The Rescue Service’s procedures are different in the case of aircraft accident and full emergency alerts.
The accident that has occurred may have been caused by incidents of varying degrees of severity: for example, an aircraft may be standing with its nose wheel off the runway, an aircraft may be missing or a crash may have occurred.
Go-around
A go-around is an aborted landing. One example of a reason for aborting a landing is that the previously landing aircraft has not yet moved off the runway. The aircraft approaching the runway aborts its landing, climbs and makes a turn in order to carry out a new landing.
Fly-by
A fly-by means that the air traffic controllers in the control tower performs a visual inspection of an aircraft while it is still airborne. The aircraft flies past the tower at the altitude of the controllers’ positions, for example to enable them to see whether the aircraft’s landing gear has been lowered.
High-speed landing
A high-speed landing is carried out when an aircraft has problems with its hydraulic system, rendering the aircraft unable to slow down before landing.
The wing area provides an aircraft with its lifting power. When the wing flaps are lowered, thus diminishing the surface of the wing, this reduces the aircraft’s lifting power as well as its speed. When the hydraulic system malfunctions, the wing flaps cannot be lowered and aircraft speed remains high upon landing.
Aircraft are capable of landing at a high speed, but passengers sitting on board the aircraft may find it an unpleasant experience.