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ARC: Abnormal runway contact - Any landing or takeoff involving abnormal runway or landing surface contact.
- Events such as hard/heavy landings, long/fast landings, off center landings, crabbed landings, nose wheel first touchdown, tail strikes, and wingtip/nacelle strikes are included in this category.
- Gear-up landings are also recorded here. However, if a system/component failure or malfunction occurred, which led to the gear up landing, the event is also coded under the appropriate system/component failure or malfunction category.
- Do not use this category for runway contacts after losing control, e.g. runway contact after take-off.
- Occurrences, in which the gear collapses during the take-off run or the landing roll are not included here except if a condition in the usage notes above has been met.
NOTE: Throughout the definition of occurrence categories the term runway or landing area is taken in its broadest sense and includes runways, landing strips, waterways, designated unimproved landing areas, and landing pads (which may include offshore platforms, building roofs, roads, ships, and fields), or other designated landing areas.
NOTE: Does not include helicopter hard/heavy landings after an off-field emergency autorotation when there was no intention to land before the autorotation was entered.
NOTE: Includes (tail) rotor striking the intended landing surface during take-off and landing. However, collisions with obstacles during take-off and landing, such as trees or walls, should be coded under CTOL.
NOTE: Does not include off-field landing by gliders.
ARC can be used for helicopter normal hard landings at an off-aerodrome landing site.
Not to be used in forced landings.
Not to be used in conjunction with USOS.