In a study conducted by the Federal Aviation Administration, it was projected that accidents and collision due to runway incursions could cause more US domestic jet deaths over the next two decades than all other accidents combined. The US National Transportation Safety Board (NSTB) believes that runway incursions are one of the most significant hazards in aviation today.
Runway incursion as defined by the International Civil Aviation Organization (ICAO) means "any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle, or person on the protected area of a surface designated for the landing and take-off of aircraft." 
In New Zealand, in spite of lesser traffic density and decreasing number of runway incursions from a peak of around 90 in 1994 to less than 40 in 2008, the Civil Aviation Authority acknowledges the timely and urgent need to raise awareness on runway incursion and the causal factors which lead to potentially disastrous incidents.
According to Transport Canada, the factors that may be a causal factor to the increase in runway incursion are:
-the increase in traffic volume which would increase the likelihood of runway incursion
-if traffic remained the same then the potential increases when capacity – enhancing procedures are put in place
-complex aerodrome layouts from improvement projects which together with inadequate signage’s, markings, aerodrome design standards and lack of standard taxi routes
-the increase in environmental pressure for optimised ATC practices which may require too many configuration changes.
Runway Incursion Examples
Location: Logan International Airport, Boston, Massachussetts
Date: 9 June 2005 (1940 Eastern Daylight Time)
Aer Lingus Flight 132 (EIN132), an Airbus 333, and US Airways Flight 1170 (USA1170), a Boeing 737, were involved in a runway incursion which occurred during daylight visual meteorological conditions. Both aircraft were under control of the Boston Air Traffic Control Tower; the Local Control West (LCW) controller was responsible for EIN132 and the Local Control East (LCE) controller was responsible for USA1170. At 2339:10, LCW cleared EIN132 for takeoff from runway 15R. Five seconds later, forgetting that he had released the runway to allow EIN132 to depart, LCE cleared USA1170 for departure from runway 9. The first officer on USA1170 saw EIN132 and pushed the control column forward to prevent the captain from taking off. Once EIN132 had passed through the intersection, USA1170 became airborne. The Airport Movement Area Safety System (AMASS) did not activate because in its configuration at that time, it was not designed to operate on intersecting runways due to the number of nuisance alerts.
Location: OHare International Airport, Chicago
Date: 23 July 2006
This three dimensional animated presentation made by NTSB shows the runway incursion incident between an Atlas Air B747 and an United Airlines B737 which was nearly catastrophic had it not been for the quick thinking pilot who rotated early to avoid the crossing B747 by 35ft. The incident reconstruction displays information from the flight data recorder, Air Traffic Communication, recorded radar data, and aircraft performance data.
Location: O'Hare International Airport, Chicago, Illinois
Date: 1 April 1999 (0220 Central Standard Time)
Air China Flight 9018 (CCA9018), a Boeing 747, and Korean Air Flight 36 (KAL36), also a Boeing 747, were involved in a near collision on runway 14R which occurred during night visual meteorological conditions. CCA9018 landed on runway 14R and was instructed by the tower controller to exit the runway via a right turn on taxiway T-10 and a left turn on taxiway K, and to cross runway 27L to the cargo ramp. The same controller cleared KAL36 for takeoff as the CCA9018 was exiting the runway. CCA9018 turned right onto taxiway T-10 and left onto taxiway M instead of taxiway K. CCA9018 entered runway 14R as KAL36 was taking off. KAL36 flew over CCA9018 by 25 to 50 feet.
Location: Los Angeles International Airport (LAX), California
Date: 01 February 1991
This is a 3D animation recreating runway incursion after the controller leaves a Skywest Airlines Flight 5569 (Fairchild Metroliner) positioned and holding while clearing the USAir Flight 1493 (Boeing B737-3B7) to land resulting in a deadly collision killing 34.
Among the factors cited by the NTSB includes LAX's handling of runways which placed much of the responsibility for the runways on the local controllers, the Metroliner's lighting, both flight crew's failure to follow "see and avoid" principles during VMC conditions and the local controller's loss of situational awareness.
Location: Chiang Kai Shek (CKS) Airport (the main international civil aerodrome serving Taipei) of Taoyuan Country, Taiwan, Republic of China (ROC)
Date: 15 July 2010
This incident involves a Singapore Airlines commercial passenger Airbus A330-300 and a Antonov Airlines cargo freighter Antonov AN-124.
The AN-124 was taxiing from the apron dedicated for cargo freighter aircraft, which is located northeast of the airport, to Runway 05 which is being used for departure flights at the time of incident. The AN-124 was required to taxi from the freighter apron via Taxiway N13, N11, NC and N1 onto Runway 05 for takeoff. The taxi route of the AN-124 requires the flight crew to cross the end of runway 05 (the starting point of Runway 23) while moving along Taxiway N13 and N11.
Despite being told to hold short of runway 05 due to a departing A330-300, the AN-124 continued to cross the runway while the A330-300 had already commenced its take off roll. Having noticed the incursion of the AN-124 onto the active departure runway 05 where the A330-300 was taking off, the Aerodrome Tower controller immediately informed the AN-124 to increase its taxi speed to evacuate from the runway. The A330-300 was approximately 1100 metres from the AN-124 as the freighter aircraft vacated the runway.
The air traffic controllers involved in the incident were suspended.
A later investigation revealed that the Aerodrome Ground controller had neglected an incorrect acknowledgement by the flight crew of the AN-124. Instead of the issued instructions for them to hold short of the active runway, the pilots had misinterpreted the earlier instructions of the Aerodrome Ground controller as “cleared to cross the runway”.
The incident highlighted the human negligence of the Ground controller to acknowledge a wrong feedback by the flight crew and subsequent failure to correct the wrong feedback by the flight crew of the AN-124. This could be due to linguistic miscommunication between the Chinese Ground controller and the Russian flight crew.
Although this runway incursion occurrence did not lead to a catastrophic event, the incident could still be studied to prevent such potentially-hazardous incidents from repeating in future. After all, aircraft incursion of a runway while another aircraft is taking off or landing on the runway is an incident with high safety risks. If the incident had occurred at a mid-intersection point of the departure runway, the two aircraft would have collided with one another.
The Civil Aeronautics Administration (CAA) of the ROC also revised the current air traffic control procedures of CKS Airport and highlighted the necessity for duty air traffic controllers to dedicate close concentration to all instruction readbacks and maintain close attention to all movements of the aerodrome.
On 11th August 2010, the CKS Airport issued a Notice To Airmen (NOTAM), informing all flight crew members to take note of three critical accident hotspot areas where a service road and two taxiways intersect the two airstrips of the CKS Airport.
AvHerald. (2010, August 19). Incident: Antonov A124 and Singapore A333 at Taipei on Jul 15th 2010, operating irregularity causes runway incursion.
Retrieved on 20 Aug 2010, from http://avherald.com/h?article=42fd4c83&opt=0.
FlightGlobal. (2010, August 19). Taipei Taoyuan reviews air control procedures after runway incident. Retrieved on 20 Aug 2010 from, http://www.flightglobal.com/articles/2010/08/19/346331/taipei-taoyuan-reviews-air-control-procedures-after-runway.html.
Location: Kansai International Airport, Osaka, Japan
Date: 20 October 2007
|Reconstruction of Event (image embedded from [http://www.skybrary.aero/index.php/File:RI_Air_Canada_Kansai_Japan.jpg] on 29 August 2010)|
On the evening of October 20, 2007, an Air Canada Boeing 767-300 passenger aircraft (Flight AC36) was taxiing towards departure Runway 24L for take off at Osaka-Kansai International Airport.
At the same time, a Japan Airlines Boeing 767-300 (Flight JL2576) was granted landing clearance on Runway 24L and was approximate 2 nautical miles from the threshold of Runway 24L.
At 1809hours Osaka Local time (0909 UTC), despite being told to hold short of Runway 24L by the Tower Controller, Flight AC36 proceeded to turn into the runway.
At 1810hours Osaka Local time (0910 UTC), the Tower Controller noticed the runway incursion and immediately instructed the Flight JL2576 to execute a go-around.
This serious incident was the result of Flight AC36 flight crew misinterpreting the hold short instructions by the Tower Controller and the subsequent negligence of the wrong read-back by the Tower Controller.
The incident highlighted that while Japan and Canada use a generally similar internationally-standardised Air Traffic Control (ATC) phraseology, usage of certain terms may bear different meanings. In this case, the usage of the word “position” may defer between Japan and Canada. While the flight crew meant moving to a line up position on Runway 24L by saying “To Position 24L, Air Canada 036”, the Tower Controller most likely interpreted that Flight AC36 stopped at the holding position of Runway 24L.
Henceforth, the varied usage of certain ATC phraseology terms in different countries could have caused mutual miscommunication between the ATC and the flight crews.
Japan Transport Safety Board. (2009, February 27). Aircraft serious incident investigation report ai2009-2. Retrieved 29 August 2010, from http://www.skybrary.aero/bookshelf/books/802.pdf.
MILAN, 8 OCT 2001:
This accident happened when a Scandinavian Airlines MD-87 heading for Copenhagen carrying 104 passengers and six crew members collided with Cessna Citation bound for Paris, France during takeoff.
Heavy fog delayed the takeoff of the MD-87. At the time of the departure, visibility improved to RVR 225m. The Cessna Citation was cleared to taxi on taxiway R5 which doesn’t cross any of the runways at Linate airport. The pilot of the Cessna Citation correctly read back the clearance but mistakenly turned onto taxiway R6, which crosses the main runway. With the fog and the unavailability of the ground radar, which was not yet operational, the controller had no chance of seeing the location of the Citation.
The Citation crossed the holding point and entered the runway as the MD-87 commenced its takeoff. The MD-87 hit the Citation during its rotation, killing all its occupants. It then proceeded to skid along the runway, veering to the right, crashing into the baggage hangar located next to the main hangar. All occupants of the MD 87 and four ground personnel were killed.
Factors Leading to Runway Incursions
“While traffic volume, capacity-enhancing procedures and aerodrome layout may increase the potential for a runway incursion, human error is the mechanism that translates this potential into an actual occurrence.” (Fisher, 2002) 
The FAA records four types of runway incursions, all are based on human error and loss of appropriate separation between aircraft and/or a vehicle: 
- Operational Errors is when an air traffic controller inappropriately clears an aircraft or vehicle into a situation that results in a collision hazard
- Operational Deviations is when a pilot moves an aircraft into a position with air traffic control approval, at a wrong time or place (different runway)
- Pilot Deviations is when a pilot moves an aircraft into a position, without air traffic control approval, that leads to a loss of separation
- Vehicle/Pedestrian Deviations is one where a vehicle or individual enters a runway without air traffic control approval that leads to a collision hazard.
Other factors that could lead to a serious ground incident includes:
- Unfamiliarity of the airport
- Limited visibility of surface movements from the tower
- No surface ground radar and traffic movement monitors
- Language / communication problem
- Airport constructions and signage projects
AIR TRAFFIC CONTROL:
-memory lapses of controllers
-communication errors between controller and pilots
-loss of situational awareness of the controllers
-not visual with traffic from the tower, poor design
- reduced reaction time due to trainee undergoing training
- separation between aircraft being miscalculated
-usage on non standard RT phraseology
-read back/hear back failures
-call sign confusion from similar call signs
-long and complex instructions
-loss of situational awareness
-inadequate support from the non flying pilot (Pilot Monitoring)
-time pressure which lead to “rushed” behaviour
-non compliance of instructions issued by ATC
-inadequate vigilance (complacency) in airports
-lack of crosschecking
-inadequate and complex design
-inadequate signage, marking and lighting systems
-airport layouts that are complex
-spacing between runways which are insufficient
FACT: Between the years 1994 to 2001, Pilot Deviation was the main cause of runway incursions in every year except 1994. The FAA has further broken down the data to show that general aviation pilots were most likely to be involved in a runway incursion. In 2000, general aviation pilots committed 76 percent of the pilot deviations.
Runway Incursion Prevention / Mitigation
The International Civil Aviation Organization (ICAO) has identified as high priority the implementation of several initiatives aimed at reducing or eliminating accidents or incidents attributable to runway incursions. They include efforts that address pilot familiarity with airports, navigation and communications improvements, pilot/controller memory and attention, controller skill development, compliance with regulations by pilots and controllers, and improved dissemination of safety/security-related information.
PRACTICES THAT MITIGATE RUNWAY INCURSION:
PLANNING OF TAXI OPERATIONS:
-prioritisation of workload – reducing workload and increasing attention during briefings will improve situational awareness
-all non critical operations to be completed before pushback
-one pilot always monitors the progress of the taxiing against the aerodrome chart
FAMILIARISATION OF AERODROME
-charts should be studied ahead of time and taxi routes reviewed with detailed briefing of the taxi routes
-latest NOTAMS reviewed with attention to closures of taxiways and runways
-when given an unexpected route or rerouted – take the time needed for reorientation of the new route
-pay attention to the location of hot spots
-usage of standard RT phraseology
-receive and confirm clearances before crossing active runways, reading back all runways crossing/ hold short clearances clearly
-never crossing red stop bars
-prioritise taxiing leaving the checklist for the appropriate time to minimise distractions
-have a clear understanding of the different ICAO phraseologies
-check for traffic before entering a runway
-ensure all pilots are aware of the ATC instruction given
-write down the taxi instruction and compare it with the aerodrome chart
-adopt a sterile flight deck
-progressively follow the aircraft’s position on the aerodrome chart
-look for visual aids and keep track of aircraft location against the aerodrome chart
-read back of clearances in its entirety to minimise ambiguity
-avoid going heads down during the taxiing phases – both pilots actively following the taxiing route
-listen out for other traffic
-if uncertain STOP the aircraft and clarify with ATC
Want to know more?
- Tenerife Airport Disaster
- This page shows a collision involving two Boeing 747 airliners (KLM 4805 and Pan Am 1736) on a runway of Tenerife, one of the island in Canary.
- Logan Airport Runway Incursion
- A near collision between US Airways (US1170) and Aer Lingus (E1132) in Boston, Massachusetts.
- USAir Flight 1493
- A collision between B737 (USAir 1493) and Fairchild Metro II (Skywest 5569)) at Los Angeles International Airport.
- Linate Airport Disaster
- Page showing Scandinavian Airlines Flight 686 colliding on take-off with Cessna Citation (D-IEVX) at Linate Airport, Milan, Italy.