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Contribution of Unstabilised Approaches to Aircraft Accidents and Incidents

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Article Information
Category: Toolkit for ATC - Stabilised Approach Stabilised Approach Awareness Toolkit for ATC
Content source: EUROCONTROL EUROCONTROL
Content control: EUROCONTROL EUROCONTROL

Description

The Flight Safety Foundation established that unstabilised approaches were a causal factor in 66 % of 76 approach and landing accidents and incidents worldwide between 1984 and 1997.

It was found that many low and slow (low energy) approaches have resulted in controlled flight into terrain (CFIT) because of inadequate vertical position awareness. Low energy approaches may also result in "loss-of-control" or "land-short" events.

High energy approaches have resulted in runway excursions and also have contributed to inadequate situational awareness in some of CFIT accidents.

It was found that a crew’s inability to control the aircraft to the desired flight parameters (airspeed, altitude, rate of descent) was a major factor in 45 % of 76 approach-and-landing accidents and serious incidents.

Flight-handling difficulties have occurred in situations which included rushing approaches, attempts to comply with demanding ATC clearances, adverse weather conditions and improper use of automation.

Consequences

Unstabilised approaches can be followed by:

  1. Runway excursions
  2. Landing short
  3. Controlled flight into terrain
  4. Hard landings
  5. Tail Strike

Contributory factors

Weather conditions or approach types which can increase the chances of an unstabilised approach are:

  1. wake turbulence
  2. strong winds
  3. low visibility
  4. heavy precipitation
  5. an approach with no visual references (e.g. night or IMC)
  6. visual approach
  7. circling approach

Aircraft Accidents and Incidents Related to Unstabilised Approach Listed on SKYbrary

  • A319, vicinity Wuxi China, 2010 (On 14 September 2010, the crew of a Sichuan Airlines Airbus A319 continued an ILS approach into Wuxi despite awareness of adverse convective weather conditions at the airport. Their inattention to automation management then led to a low energy warning and the inappropriate response to this led to the activation of flight envelope protection quickly followed by a stall warning. Inappropriate response to this was followed by loss of control and a full stall and high rate of descent from which recovery was finally achieved less than 900 feet agl.)
  • A319, Montego Bay Jamaica, 2014 (On 10 May 2014 the crew of an Airbus A319 failed to manage their daylight non-precision approach at destination effectively and it culminated in a very hard touchdown which exceeded landing gear design criteria. The Investigation concluded that the comprehensively poor performance of both pilots during the preparation for and execution of the approach could be attributed to both their repeated failure to follow SOPs and retain adequate situational awareness and to a failure of the aircraft operator to fully deliver effective training even though both this training and its SMS met relevant regulatory requirements and guidance.)
  • JS32, Torsby Sweden, 2014 (On 31 January 2014, an Estonian-operated BAE Jetstream 32 being used under wet lease to fulfil a government-funded Swedish domestic air service requirement landed long at night and overran the end of the runway. The Investigation concluded that an unstabilised approach had been followed by a late touchdown at excessive speed and that the systemic context for the occurrence had been a complete failure of the aircraft operator to address operational safety at anything like the level appropriate to a commercial operation. Failure of the responsible State Safety Regulator to detect and act on this situation was also noted.)
  • CRJ2/ATP, Stockholm Sweden, 2011 (On 21 January 2011, a Belarusian Bombardier CRJ200 failed to fly the prescribed missed approach procedure at night in IMC and when ATC observed a developing conflict with another aircraft which had just departed another runway with a conflicting clearance, both aircraft were given heading instructions to mitigate the proximity risk. The resulting CPA was 1.8nm at an altitude of 1600 feet. The subsequent investigation attributed the pilot error to a change of aircraft control in the flare when it became apparent that a safe landing was not assured.)
  • A306, vicinity Nagoya Japan, 1994 (On 26 April 1994, the crew of an Airbus A300-600 lost control of their aircraft on final approach to Nagoya and the aircraft crashed within the airport perimeter. The Investigation found that an inadvertent mode selection error had triggered control difficulties which had been ultimately founded on an apparent lack understanding by both pilots of the full nature of the interaction between the systems controlling thrust and pitch on the aircraft type which were not typical of most other contemporary types. It was also concluded that the Captain's delay in taking control from the First Officer had exacerbated the situation.)
  • … further results


Stabilised Approach Awareness Toolkit for ATC

Further Reading

CANSO

Part of the Stabilised Approach Awareness Toolkit for ATC