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Runway Identification
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Definition
Runway Identification is the unequivocal association of a runway with its correct identity when using it for a landing or take off, or when manoeuvring an aircraft on the ground in its vicinity.
Description
Accident and incident reports reveal that flight crew periodically misidentify the runway designated for take off or landing. Sometimes the outcome has been a fatal accident but more usually, just the heightened risk of one. The unintended use or attempted use of parallel taxiways has in the past been at least as common as Wrong Runway Use. In extreme cases, large aircraft on public transport flights have been landed on runways that are not even at the right airport. Runway Misidentification can result in runway incursion, runway excursion and wrong runway use.
The Take Off Case
The most typical take off case involves a departing aircraft lining up on a parallel taxiway after being cleared to do so on the adjacent runway. There are also cases of aircraft lining up on the runway edge lights in the mistaken belief that they were runway centreline lights and, since this error can be difficult for ATC to detect, then making a take off on this false alignment. Such errors usually occur either in restricted visibility or at night. See for example the take off by an ATR 72 from Dresden, Germany in 2002 (upload due-ConList No 152) and B738, Oslo Gardermoen Norway, 2005 (RE HF) which both occurred at night. However,the serious incident A320, Oslo Norway, 2010 (RE HF) when a take off from the same parallel taxiway as the one involved in the 2005 incident was made in daylight in the presence of frozen deposits on the manoeuvring surfaces. Norway is somewhat unusual in that it uses surface markings which are contrary to the ICAO Standard usually encountered. This is apparently a state-wide response to the perceived difficutites with standard white markings in the winter period when a 'back to blacktop' policy for removal of frozen deposits is frequently considered to be impracticable.
Less often, and usually in the presence of complex airport layouts, a runway parallel or nearly parallel to that authorised is inadvertently used for take off - see for example B732, Seattle WA USA, 2006 (RE HF). If a wrong runway is involved and it is closed or partially closed for Runway Maintenance, then the eventual outcome, if the line up error is undetected, can be a collision with obstructions - see for example B744, Taipei Taiwan, 2000 (RE FIRE HF). More often, a take off from a parallel taxiway is (just) successful, albeit with considerably reduced margins of safety which leave no margin for unexpected occurrences during the take off roll - see for example A343, Anchorage AK USA, 2002 (RE HF) .
The Landing Case
The most typical take off case involves a landing on a taxiway parallel to the correct runway, by day or by night. See for example B732, London Gatwick UK, 1993 (RE HF) and B739, Akita Japan, 2007 (RE HF). Less often another runway at the same airport is inadvertently used; even less often, a runway with a similar orientation in the vicinity of the extended centerline of the correct runway, but at a different airport, is used.
The Common Feature
Almost all occurrences where the correct runway was not positively identified have been because of complacency in visual acquisition. The failure usually occurs when a paved surface near to the correct one is selected, which has the same orientation. An exception is CRJ1, Lexington KY USA, 2006 (HF RE FIRE).
In most departure cases and almost all landing cases, visual reference is not restricted and there is simply a complete absence of any attempt at positive runway identification. Most documented occurrences have involved multi-crew aircraft, which indicates an additional failure of the effectiveness of monitoring by the PM. Incidents involving operations in restricted visibility occasionally feature in the take off case; but it appears that the more rigorous procedures and heightened flight crew awareness of the scope for inadvertent error which apply in these circumstanced are generally effective.
Defences
- Pre flight briefing should include a review of airport layouts which are not wholly familiar to any member of the flight crew
- Ensure that Flight Crew progressive position awareness is maintained during taxi out. A check for the correct take off position alignment alone cannot provide assurance that the aircraft is on the correct runway (although of course a check against the ILS LLZ display - can).
- At all times ensure that the monitoring of the actions of PF by PM is effective.
- If a straight-in ILS approach is being flown to minimums or near minimums, flight crew should double check that the frequency tuned and the audio ident correspond to the correct runway.
- If an offset ILS, any non precision approach (NPA), a circling approach or an entirely visual approach is being flown, the approach briefing should include discussion of how positive runway identification will be accomplished.
- Runway Lighting is coloured completely differently to Taxiway Lighting and should provide a normally alert flight crew with an opportunity to distinguish one from the other.
- If ATC have surface movement radar or better to track aircraft ground movements, this can prevent an error in runway identification from having a serious consequence. If time permits or if there is are any indications of position uncertainty in respect of a particular aircraft, especially in restricted visibility conditions, then active aircraft ground position monitoring is especially valuable prior to the issue of a take off clearance. A-SMGCS can additionally provide a range of alerts where an aircraft fails to follow its issued clearance.
- The addition of RAAS functionality to ‘standard’ TAWS provides a direct means of confirming that runway identification is correct.