ACAS (Airborne Collision Avoidance System) refers to a system which warns pilots of the threat of collision and which meets the requirements for ACAS II systems set out in Appendix 10, Volume IV Chapter 4 (version 7) of the Convention on International Civil Aviation. This system relies on information exchanges between aircraft transponders, based on which pilots are given advisories and alerts of the presence of other aircraft nearby. A system that meets the ACAS II requirements is known as a TCAS (Traffic Collision Avoidance System). The system issues either Traffic Advisories (TA) or Resolution Advisories (RA).
An accident refers to an occurrence associated with the operation of an aircraft which, in the case of a manned aircraft, takes place between the time any person boards the aircraft with the intention of flight until such time as all such persons have disembarked, or in the case of an unmanned aircraft, takes place between the time the aircraft is ready to move with the purpose of flight until such time it comes to rest at the end of the flight and the primary propulsion system is shut down, in which
a) a person is fatally or seriously injured as a result of
• being in the aircraft, or
• direct contact with any part of the aircraft, including parts which have become detached from the aircraft, or,
• direct exposure to jet blast,
except when the injuries are from natural causes, self-inflicted or inflicted by other persons, or when the injuries are to stowaways hiding outside the areas normally available to the passengers and crew; or
b) the aircraft sustains damage or structural failure which adversely affects the structural strength, performance or flight characteristics of the aircraft, and would normally require major repair or replacement of the affected component, except for engine failure or damage, when the damage is limited to a single engine, (including its cowlings or accessories), to propellers, wing tips, antennas, probes, vanes, tires, brakes, wheels, fairings, panels, landing gear doors, windscreens, the aircraft skin (such as small dents or puncture holes) or minor damages to main rotor blades, tail rotor blades, landing gear, and those resulting from hail or bird strike, (including holes in the radome);
c) the aircraft is missing or is completely inaccessible.
A serious injury means an injury which is sustained by a person in an accident and which involves one of the following:
a) hospitalisation for more than 48 hours, commencing within 7 days from the date the injury was received;
b) a fracture of any bone (except simple fractures of fingers, toes, or nose);
c) lacerations which cause severe haemorrhage, nerve, muscle or tendon damage;
d) injury to any internal organ;
e) second or third degree burns, or any burns affecting more than 5% of the body surface;
f) verified exposure to infectious substances or harmful radiation.
A CFIT/near CFIT situation (Controlled flight into or towards terrain, CFIT) is a situation where an airworthy aircraft under the complete control of the pilot is inadvertently flown (or nearly flown) into terrain, water or an obstacle.
Commercial air transport refers to using aircraft for transporting passengers, cargo or mail against payment or other compensation.
European Aviation Safety Agency (EASA) is an agency of the European Union established in 2002 by Regulation (EC) No 216/2008 of the European parliament and the Council in order to ensure a high and uniform level of safety in civil aviation, by the implementation of common safety rules and measures.
Foreign commercial air transport means the transport of passengers, cargo or mail against payment or other compensation using other than a Finnish aircraft, or under an operating licence not issued in Finland.
General aviation refers to all other domains of aviation apart from commercial air transport and aerial work. NB. In this publication, general aviation and aerial work are dealt with as a single category. Recreational aviation is also handled as a separate category.
A ground collision while taxiing to or from a runway in use (Ground collision, GCOL) is a situation where an aircraft comes into contact with another aircraft, a vehicle, a person, an animal, a structure, a building or any other obstacle while moving under its own power in any part of the airport other than the active runway, excluding power pushback.
The International Civil Aviation Organisation (ICAO) is a civil aviation organisation operating under the auspices of the United Nations.
Loss of control in flight (LOC-I) means a situation where the pilot loses control of an airborne aircraft, resulting in a significant deviation from the aircraft’s intended flight path. The loss of control may be total or momentary and caused by such factors as human error, mechanical faults or external factors.
A mid-air collision (MAC) and a near miss/AIRPROX is a situation where airborne aircraft come into contact with one another or in which the distance between aircraft as well as their relative positions and speed have been such that the safety of the aircraft involved may have been compromised.
Recreational aviation refers to the operation of a glider, motor glider, ultra-light aircraft, autogyro and hot-air balloon, hang gliding and paragliding, as well as parachuting. NB. If a hot air balloon is used to transport passengers against a fee, this constitutes commercial air transport. This publication does not deal with hang gliding, paragliding or parachuting.
Runway excursion (RE) refers to uncontrolled exit by an aircraft from a runway during take-off or landing. This may be unintentional or intentional, for instance as the result of an evasive manoeuvre.
Runway incursion (RI-VAP) is any situation where an aircraft, vehicle or person is present on the runway or its protected area, without clearance or otherwise incorrectly. This includes low approaches executed without clearance or otherwise incorrectly.
A serious incident means an incident involving circumstances indicating that there was a high probability of an accident and is associated with the operation of an aircraft, which in the case of a manned aircraft, takes place between the time any person boards the aircraft with the intention of flight until such time as all such persons have disembarked, or in the case of an unmanned aircraft, takes place between the time the aircraft is ready to move with the purpose of flight until such time it comes to rest at the end of the flight and the primary propulsion system is shut down. A list of examples of serious incidents is set out in the Annex to Regulation 996/2010 (EU) (Ulkoinen linkki).