Ground Collision: How to Avoid GCOL Incidents and Accidents?

by Admin on September 8, 2022

Ground collision is a collision that occurs while an aircraft is taxiing to or from a runway in use. This collision includes crashing with aircraft, people, ground vehicles, obstacles, buildings, structures, etc.

ICAO calls GCOLs event categories. This is a category used to classify events (i.e. accidents or incidents) at a high level to enable data analysis to support safety solutions. It is important to note that ICAO classifies pushback, powerback and towing events as RAMP events. Collisions that occur while the aircraft is moving under its own power in a gate, ramp, or tie-down area (excluding powerbacks) are encoded as GCOL.

The GCOL event category is one of several categories. Other categories are:

  • Abnormal Runway Contact (ARC): Bumped, off-centre, or crooked landings, wing tip flaps, and other types of abnormal runway contact can contribute to delayed or incomplete deployment of the stopping device, resulting in , may increase stopping distance.
  • Bird Strike (BIRD): Defined as a collision between a bird and an aircraft in flight or during takeoff or landing roll. The term is often extended to cover other wildlife attacks, such as bats and ground animals.It can pose a serious threat to aircraft safety. Significant structural damage can occur in small aircraft, and all aircraft, especially those with jet engines, can lose thrust from birds sucking into the engine’s air intakes. This has resulted in several fatalities. It is most likely to occur during takeoff, initial climb, approach, and landing stages due to the high numbers of birds in flight at low altitudes.
  • Runway Excursion (RE): It’s a runway safety incident in which an aircraft improperly takes off from a runway. Runway excursions include runway overruns where the aircraft cannot stop before reaching the end of the runway. Runway deviations can occur due to pilot error, bad weather, or aircraft malfunction
  • Runway Incursion (RI): It’s Any incident at an airfield involving the inadvertent presence of an aircraft, vehicle or person in the restricted area of ​​the aircraft landing and take-off area.
  • Loss of Ground Control (LOC-G) and Collision: It is loss of control of an aircraft in flight or deviation from its intended flight path. It is an extreme deviation from the intended trajectory.
  • Obstacles (CTOL): Conventional take-off and landing, also known as horizontal take-off and landing (HTOL), is the process by which a conventional fixed-wing aircraft (such as an airliner) takes off and lands on a runway.
  • Undershoot/Overshoot (USOS): A touchdown from the runway surface close to the runway. It also includes an offside touchdown.

They’re classified by ICAO as relevant to runway safety. Runway safety incidents have been identified by ICAO as one of three high-risk accident categories. Other high-risk categories are:

  • Loss of control in flight (LOC-I)
  • Controlled flight into terrain (CFIT).

Partnering with a trusted flight support company is the solution to avoid any aircraft accidents or crashes on ground, with iJET flight support All risks can be mitigated with a professional team coordinating your aircraft ground handling smoothly with high level of performance.


Top Reasons of Ground Collision


  • Stakeholders have failed to actively ensure that aircraft do not collide with other aircraft as they traverse the tarmac and that jet engine emissions from larger aircraft do not pose a threat to smaller aircraft.
  • Failure to actively mitigate the risk of impact damage to parked aircraft, or to ensure that maintenance checks are performed prior to further flight maneuvers, even for seemingly minor impacts.
  • Failure to provide proper signage, marking and lighting to enable crews to comply with tax procedures.
  • Failure to ensure safe parking and docking of aircraft.
  • Failure to train to a quality level consistent with aviation professionals, various types of unauthorized contractors and subcontractors who perform and supervise aircraft ground handling operations on the tarmac and/or near aircraft parking areas or gates.



Scenarios of Ground Collision GCOL

Safety Improvement Sub-Group SISG scenario analysed 20 ground safety events, including both RIs and ground crashes. Some events were accidents, some were incidents, below are examples of areas and risk aspects reviewed:

  • Taxiway landing/departure after failure to comply with ATC clearance due to spatial/positional confusion.
  • Landing/departing from taxiway after failing to comply with ATC clearance due to clearance misunderstanding or misheard.
  • Poor Crew Resource Management (CRM) or Forgotten Planned Actions cause the aircraft to take the wrong guidance route.
  • Due to inadequate CRM or a forgotten planned action, the aircraft erroneously enters the runway in the maneuvering area without ATC clearance.

How to Avoid Ground Collision?

Automatic Ground Collision Avoidance System (Auto GCAS)


Auto-GCAS was developed jointly by Lockheed Martin Skunk Works, the Air Force Research Laboratory, and the National Aeronautics and Space Administration (NASA), Auto GCAS is designed to reduce accidents known as Controlled Flight into Terrain (CFIT). According to U.S. Air Force statistics, CFIT incidents account for 26% of aircraft losses and 75% of all F-16 pilot fatalities.

The system consists of a complex suite of collision avoidance and autonomous decision-making algorithms that use precise navigation, aircraft performance and onboard digital terrain data to determine if a ground collision is imminent. To do. If the system predicts an imminent collision, it will command an autonomous avoidance maneuver (wing level roll and +5 g drag) as a last resort to avoid a ground impact.

Auto-GCAS runs in the background and automatically provides protection even if the pilot is distracted, tired of the task, incapacitated or unconscious. Although the system has a pilot override feature, no pilot action is required.


Real Examples of Some Accidents and Incidents in GCOL

B732, vicinity Washington National DC USA, 1982

A Boeing 737-200 took off from Runway 36 at the Washington National during the day in moderate snowfall, but stalled before colliding with a bridge or vehicle, leaving only 1 After a minute’s flight, it plunged into the river below, killing most of the inmates and some people on the ground. The accident was entirely due to a combination of crew actions and omissions related to the prevailing adverse weather conditions and, most importantly, failure to select engine anti-ice, resulting in an over-reading of actual engine thrust.


B738/B763, Barcelona Spain, 2011

On April 14, 2011, a Boeing 737-800 did not leave enough space while taxiing behind a stationary Boeing 767-300 in Barcelona, ​​causing the 737’s wingtip to hit the 767’s tailplane. collided and damaged both. The 767 crew were unaware of the collision, while the 737 crew were aware of the proximity but dismissed flight attendant reports that passengers witnessed the collision. Both aircraft completed their scheduled flights without incident, but damage was subsequently discovered that required repair before the 767 could be flown further.


FA7X, London City UK, 2016

Dassault Falcon 7X was maneuvered into an unmarked parking position after arriving at London City Airport, when it was erroneously steered into another manned stationary aircraft. Crashed and severely damaged. Investigation revealed that the affected apron was congested, and although the aircraft had been maneuvered with the assistance of wingwalkers in accordance with airport procedures, the sharp corrective turn that produced the “wing growth effect” was a collision hazard. and concluded that the signal was given at the end of the minute by a pedestrian on the wing involved and was not seen by the flight assistant.


B789 / A388, Singapore, 2017

A Boeing 787 taxiing to depart Singapore at night was involved in a minor collision with a parked Airbus A380 that had just been pushed back from the gate and was about to depart. An investigation determined that the cause of the collision was poor control of the GND by the trainee under his supervision and inadequate caution by the crew of his 787 in the face of a possible collision with the A380. concluded to be the cause. The safety recommendations made were primarily related to ATC procedures where it was considered that there was room for improvement in risk management.


Rely on iJET flight support for a comfort trip from A to Z as it offers different services to operate and your mind is stress free

Subscribe to iJET Latest News & Promotions

    iJET Limited Certified: ISO 9001:2015