The world’s worst airline disaster occurred on a runway when in 1977 582 persons were killed as a KLM Boeing 747 which was taking off slammed into a PAN AM 747 in the Canary Islands. There have been numerous incidents and accidents relating to runway incursions both before and after that fateful event. One of the more significant was the Comair accident which sent flight 5191 onto a wrong runway sending 49 people to their deaths.
by Dr. Ruwantissa Abeyratne
(June 07, Montreal, Sri Lanka Guardian) There is no doubt that the demand for air transport is growing. Exponentially. Airbus Industrie has forecast that almost 26,000 new passenger and freighter aircraft valued at US$3.2 trillion will be needed between 2010 and 2029. Out of the almost 26,000 additional passenger and freighter aircraft needed, around 25,000 will be passenger aircraft valued at over US$2.9 trillion. Of these additional passenger aircraft, 10,000 will replace older less eco-efficient aircraft and some 15,000 will be for growth. Taking into account today’s passenger fleet of over 14,000 aircraft, the world passenger fleet will rise to some 29,000 aircraft by 2029.
The question that the industry would face is, where would all these aircraft be accommodated, given the finite land we have? Foremost among the concerns would be global runway safety.
Runway safety has four aspects to it: Runway incursions; runway excursions; foreign objects and debris (called FOD); and bird strikes against aircraft.
A runway incursion is 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. The Canadian Aviation Safety Board (now the Transportation Safety Board of Canada (TSB)) issued a report In 1987entitled Report on a Special Investigation into the Risk of Collisions Involving Aircraft on or Near the Ground at Canadian Civil Airports. The report stated that both the Canadian and U.S. experience would suggest an extremely wide range of cause-related factors for the occurrences which involve actual or potential ground conflicts, and identified unexpected human behavior as by far the most common causative factors in such occurrences.
Information pertaining to the proximity of aircraft and/or the vehicle; geometry of the encounter; evasive or corrective action; available reaction time; environmental conditions, weather, visibility and surface condition; and factors that affect system performance are all necessary to properly classify the severity of a runway incursion. An operational error is an occurrence attributable to an element of the air traffic control (ATC) system which has two results, the first being two or more aircraft coming within less than the minimum separation minima or between an aircraft and obstacles (vehicles, personnel and equipment on runways) and the second being an aircraft landing or departing on a runway closed to aircraft after receiving air traffic authorization; and a vehicle or pedestrian deviation – an occurrence resulting from a vehicle operator, non-pilot operator of an aircraft or pedestrian deviating onto the movement area including the runway without ATC authorization.
The world’s worst airline disaster occurred on a runway when in 1977 582 persons were killed as a KLM Boeing 747 which was taking off slammed into a PAN AM 747 in the Canary Islands. There have been numerous incidents and accidents relating to runway incursions both before and after that fateful event. One of the more significant was the Comair accident which sent flight 5191 onto a wrong runway sending 49 people to their deaths. A similar incident occurred in 1993 where a pilot who was cleared for take of on a particular runway, accidentally chose a shorter one. In March 2006, the Federal Aviation Administration investigated three close calls at Chicago’s O’Hare Airport. The first involved a Lufthansa jet and Delta Airlines plane that came within 100 feet of each other after both were cleared for take of from intersecting runways. The second incursion involved a United Airlines plane two days after the Lufthansa – Delta incident, which was instructed to take off from a runway already assigned to another carrier. The third incursion took place in mid March 2006 when a regional jet was cleared for takeoff on a runway moments before an Airbus A320 was cleared for takeoff on a runway that would have connected to the one to be used by the regional jet.
A runway excursion occurs when an aircraft departs the runway in use during the take-off or landing run and that such an excursion may be intentional or unintentional. A runway excursion may occur when a departing aircraft fails to become airborne or successfully reject the take off before reaching the end of the designated runway. Another instance would be when a landing aircraft is unable to stop before the end of the designated runway is reached.
There are a couple of instances on runway excursions worth noting. On 14 October 2004, an MK Airlines Boeing 747 collided with terrain at Halifax International Airport, Nova Scotia due to reduced power at take off. The Aviation Investigation Report issued by Transport Canada revealed inter alia that at the time of the accident, MK Airlines was using the Boeing Laptop Tool (BLT) for determining performance calculations. The BLT is a Microsoft Windows based software application used to calculate take-off performance data, landing performance data, and weight and balance information. The Report also revealed that the company did not have a formal training and testing program on the BLT, and it was likely that the user of the BLT in this occurrence was not fully conversant with the software.
On 2 August 2005, an Airbus A 340-313 aircraft (Flight AFR 358) overran Toronto’s Pearson International Airport through heavy rain and caught fire. All passengers were safely evacuated. The Aviation Investigation Report issued by the Transportation Safety Board of Canada discusses four causative factors put forward by the National Aeronautics and Space Administration (NASA) of the United States as likely to contribute to decision errors of the flight crew: ambiguity of information; dynamically changing risks; goal conflicts (organizational or social pressures; and unanticipated circumstances. The Accident Investigative Report discusses that low ceiling and poor visibility due to thunderstorms; rapid changes in surface pressure; lightning, hail, both within and outside a cloud, icing, damaging wind gusts and down drafts due to microbursts can all contribute to the unsafe operation of an aircraft while landing or takeoff. One of the decisions taken by Transport Canada after the accident was to build safety areas at the ends of runways at Canadian airports.
It is very clear that there are several actors involved in an accident pertaining to a breach of runway safety. They are mainly: the State and its relevant instrumentalities; the flight crew; the air navigation service provider; and the airport.
A foreign object or debris (FOD) is any object that does not belong in or near airplanes. Damage occurs when a FOD injures airport or airline personnel and damage airplanes. These debris may include any object found in an inappropriate location that -- as a result of being in that location -- can damage equipment or injure airplane or airport personnel. FOD is known to include a wide range of material, including loose hardware, pavement fragments, catering supplies, building materials, rocks, sand, pieces of luggage, and even wildlife. FOD is found at terminal gates, cargo aprons, taxiways, runways, and run-up pads. It causes damage through direct contact with airplanes, such as by cutting airplane tires or being ingested into engines, or as a result of being thrown by jet blast and damaging airplanes or injuring people.
On 25 July 2000 the Concorde (registered F-BTSC) operated by Air France took off from Paris Charles de Gaulle on a charter flight to New York with nine crew and one hundred passengers on board. On takeoff, one of its tires went over a FOD left behind by a departing aircraft that had used the runway on which the Concorde was taking off. This caused the Concorde’s tyre to burst and parts of the tyre to be ingested into one of its engines, causing a fire. The aircraft crashed into a hotel at La Patte d’Oie in Gonesse. All 109 persons in the aircraft perished and 4 others on the ground also died as a result of the collision.
The Final Report of the Investigation identified the following causes as probable in the context of the accident: high-speed passage of a tyre over a part lost by an aircraft that had taken off five minutes earlier and the destruction of the tyre; the ripping out of a large piece of tank in a complex process of transmission of the energy produced by the impact of a piece of tyre at another point on the tank, this transmission associating deformation of the tank skin and the movement of the fuel, with perhaps the contributory effect of other more minor shocks and /or a hydrodynamic pressure surge; Ignition of the leaking fuel by an electric arc in the landing gear bay or through contact with the hot parts of the engine with forward propagation of the flame causing a very large fire under the aircraft’s wing and severe loss of thrust on engine 2 then engine 1; and In addition, the impossibility of retracting the landing gear probably contributing to the retention and stabilisation of the flame throughout the flight.
A bird strike is a collision between a bird and an aircraft which is in flight or on a takeoff or landing mode. However, this term is also used for aircraft collisions with other animals such as bats or other animals on ground. On 15 January 2009, US Airways Flight 1549 took off from La Guardia Airport in New York City at 3:03 P.M. Eastern time on its way to Charlotte, N.C., with 150 passengers and five crew members on board. As it gained altitude, it reportedly ran into a flock of geese, necessitating the ditching of the aircraft on the Hudson River. On 3 October 2006, a Boeing 767-300, departing from Melbourne Australia on an internal flight, ran into a flock of gulls at rotation with evident ingestion and damage to the left engine. The flight crew considered the ingestion was not sufficiently serious to justify a return to land and the intended internal flight was completed. On March 4, 1999, a DC91 operated by USA Jet Airlines, at night and on final approach to land at Kansas City International Airport encountered a flock of large birds. The crew managed to regain sufficient thrust to continue the approach and land without further incident. On 6 December 1997, a British Airways Boeing 747-100, departing from London Heathrow airport, had an engine bird strike just after takeoff, causing substantial damage and falling debris.
Like aircraft, migratory birds also follow well-defined flight paths in numbers and their close proximity to an airport could be hazardous to aircraft landing and taking off in the vicinity. In addition, birds are attracted to open areas of grass and water as well as shrubs and trees which provide food for birds. The issue of bird strikes takes on an added dimension by affecting social and policy issues which are not strictly linked with air transport. The key area of environmental protection - particularly in the fields of wildlife policy and habitat management - brings to bear issues of State responsibility for national policy as well as a commitment towards maintaining the bio-diversity of the ecosystem. An example of dire consequences of a bird strike can be cited in the instance of a Boeing 747 aircraft departing Los Angeles Airport in late August 2000, which had to dump 83 tons of fuel to land safely after a bird strike.
Measures to mitigate the problem
There are several measures that can be taken to mitigate the problem. Although “one size does not fit all” in the context of aircraft, airports and aerodromes of the world, there is a compelling need for harmonization and standardization in order to ensure interoperability. In this context “harmonization” was recognized as consistency and compatibility and “standardization” was recognized as conformity. It was stringently argued that pilot error always plays some part in breaches of runway safety and that such error could be avoided if the flight crew were to adhere to standardization, i.e. follow the instructions on takeoff, approach and landing;
There should be collaboration to ensure runway safety at multiple levels and international organizations must work together in ensuring such collaboration. Runway safety teams ( a team comprised of representatives from aerodrome operations, air traffic service providers, airlines or aircraft operators, pilot and air traffic controllers associations and any other group with a direct involvement in runway operations that advise the appropriate management on the potential runway incursion issues and recommend mitigation strategies) must be established locally and hosted by airports;
Standardization and harmonization must be improved. In this regard guidance must be developed to launch runway safety teams; runway safety definitions must be harmonized along with taxonomies and reporting conditions; and communications procedures must be standardized and improved upon.
Implementable solutions must be promoted and encouraged through appropriate training; runway and taxiway marking; implementation of a Performance Based Navigation (PBN) approach and runway end safety programmes. Finally, runway safety should be monitored through a Continuous Monitoring Approach (CMA) as introduced by the International Civil Aviation Organization.
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