Good morning. Thank you for inviting me to speak to you today about airport safety, a topic that is high on the National Transportation Safety Board's list of concerns.
Passengers who have concerns about flying tend to worry most about the part of their trip that involves being unnaturally separated from the ground. Because we are so concerned about airport safety, 3 weeks ago we held a runway incursion forum, Promoting Runway Safety. Before this forum, few members of the general public knew that the worst accident in aviation history was a runway collision. During a typically foggy day, a KLM 747 took off without a clearance and collided with a Pan Am 747 that was taxiing on the runway. Sadly, 583 people lost their lives.
Captain Robert Bragg, the First Officer of the Pan Am 747, showed us photographs and relayed the harrowing events that he survived 30 years ago. Without a doubt, airport safety is an important issue! Everyone in the aviation industry can positively contribute to airport safety. We don’t only need technological improvements; airport safety requires that each person who is on the airport surface be aware of their location and their surroundings.
Those of us who work in the aviation safety business know that surface operations present some of the most challenging situations for pilots and controllers, and in many cases leave the least room for error. On the airport surface, potentials for traffic conflicts are exacerbated by the myriad of ground support vehicles, including maintenance vehicles, cleaners, fuelers, baggage carts, caterering trucks, snow plows and all sorts of other ground traffic vying for space on a busy airport. In the air, we try to maintain miles of space between aircraft. But, on the airport, the tolerances are comparatively small; the difference between being in a safe place and an unsafe place is measured in feet, not miles. Caution and vigilance are gate-to-gate necessities not only for pilots and controllers, but also for ground support vehicle operators, - and as you know occasionally things even go wrong at the gate.
The hazards of airport surface operations have been a concern of the Safety Board for over 30 years. Since 1973, we have issued over 100 safety recommendations related to runway incursions. These recommendations addressed the need for improvements in air traffic control operations, training and hardware; pilot training; airport signs, lighting and markings, aircraft conspicuity and incident reporting.
The runway incursion issue has been on the Board's Most Wanted List since its inception in 1990. In the late 1980s, an inordinate number of runway incursions/ground collision accidents resulted in substantial loss of life and the Safety Board issued numerous safety recommendations addressing the issue. The FAA completed action on a number of important objectives to make the ground operation of aircraft safer. However, these incidents continue to occur with alarming frequency.
In 2006 there were 330 incursions and, if we continue at the current rate, we’ll surpass that figure in 2007. While the numbers are interesting, we also must focus on severity. Runway incursions are categorized from A through D according to collision risk, with category A and B incursions presenting the highest likelihood of collision. Over the last 3 years the number of serious events have continued to climb. In 2004 there were 28; 2005, 29; and in 2006, there were 31. Any one of these events had the potential to be a catastrophic accident.
Just this year we’ve had 3 near collisions. Two were at Denver International. The first happened at the beginning of January when a Frontier Airbus narrowly missed landing on top of a Metroliner that had inadvertently taxied onto the runway. The second involved a United 737 that almost collided with a snow plow that had crossed the takeoff runway without a clearance. And just last month, in Las Vegas, the controller cleared an Alaska 737 for immediate takeoff then had to cancel the clearance when it appeared that another aircraft on an intersecting runway was going to enter Alaska’s runway. Alaska successfully aborted their takeoff well above 100 kts, but not without damaging the airplane’s tires. Those are 3 very serious events that happened in just 3 months.
In Denver, AMASS, alerted the controllers to the mistake that was made by the pilot just about the time the Frontier airplane was going to touch down. The crew saw the metroliner before the controller was able to issue the warning. In the last two situations, the system did not provide adequate warning.
We have animations of 6 near collisions that were a result of runway incursions. If you’re interested in seeing those animations, they are available on our website, www.ntsb.gov. The graphics really show how narrow the margin of safety becomes when we’re talking about runway incursions.
These incidents and others continue to be of serious concern to the Safety Board. Despite the efforts of pilots, controllers, FAA management, and airport operators to mitigate the risks of surface operations, the continuing occurrence of hazardous incidents shows that we still have work to do.
Analysis of several near-collisions has shown that AMASS performance is not adequate to prevent serious accidents. As evidenced by the Denver incident, in some cases the system does not provide an alert at all, and when it does alert in critical situations such as the first Denver incident involving Frontier and the metroliner, the warning may come so late as to be of little use. In addition to the incidents I just described, the Board is aware of several near-collisions occurring at AMASS-equipped airports that were prevented not by virtue of a timely warning from the system, but instead were resolved through flight crew actions sometimes bordering on the heroic - along with a lot of luck. That is not good enough.
In order to ensure that all commercial passengers receive effective protection against the dangers of runway incursions, the Board has urged the FAA to develop and demonstrate the effectiveness of ground movement safety systems appropriate for use at a variety of airport types ranging from large international airports to the smaller regional airports served only by commuter airlines. We do not expect that the answer will be a "one size fits all" system, but will instead require creative use of different combinations of sensors, processors, and warning methods tailored to the requirements of each situation. At small and uncomplicated airports, simple methods of aircraft detection and warning may be sufficient, while at complex and busy airports a more elaborate approach may be needed. In the forum that I mentioned before, several companies displayed their products indicating that there are various technologies already available that could help prevent incursions.
We know delivering technological solutions takes time, but the hazards are here now. Consequently, over the past few years the Safety Board has made other recommendations that we believe will improve runway safety without requiring lengthy development periods. For example, we have recommended that the FAA promote more rigorous standards for the marking of temporarily closed runways, in order to minimize the chances of an inadvertent takeoff or landing. Our intent is that the effort put into preventing access to closed areas is commensurate with the hazard of inadvertent use. For example, if a runway is closed briefly to allow paint to dry or because of other benign conditions unlikely to threaten safety in the event of a pilot or controller error, minimal effort would be required. In contrast, if the condition of the surface or the presence of men and heavy equipment renders a serious accident virtually certain in the event of an inadvertent takeoff or landing, the Board believes that substantial prevention efforts are needed. This may require physical access barriers, lighted "X" markings, or other methods for sending pilots an unmistakable message that a runway is not available for use.
Other recommendations have addressed the use of air traffic procedures such as holding aircraft on runways, communications techniques used by controllers, implementation of ICAO standards within the US ATC system instead of US-only procedures, and revision of Federal Air Regulations regarding the need for specific clearance to cross a runway rather than the implied crossing permission that currently comes with certain types of taxi clearances. Our European counterparts have made similar recommendations in response to accidents and incidents occurring within their own area of responsibility.
Operational procedures must take into account the inevitability of human error and, whenever possible, be designed to provide redundancy in order to eliminate the possibility that a single human or equipment failure will lead to a catastrophic accident.
Our recommendations are often intended to improve the awareness of pilots and controllers, so that if one makes a mistake, the other has an opportunity to notice and react. In some cases, this objective suggests that the use of procedures such as "position and hold" (where an aircraft waits on the runway for departure clearance rather than waiting on the taxiway) be limited to circumstances where the runway environment is visible to the crews of landing aircraft in time to execute a go-around if necessary to avoid a ground conflict.
We have also asked the FAA to require that controllers issue traffic advisories when aircraft are landing on converging runways, so that the pilots are aware of the potential conflicting traffic and can respond in a timely manner if spacing is less than needed for a safe landing.
Such recommendations often meet resistance in the form of assertions that redundancy is not needed if everything goes the way it's supposed to. Unfortunately, virtually all of the Safety Board's workload comes from situations where everything doesn't go the way it's supposed to, and often only a minor change in the sequence of events would have turned the accident or incident into a non-event. We'll do whatever it takes to increase the number of non-events in the system - that's one of our main criteria for "having a good year," and I'm sure you all share that goal.
I thank you for allowing me to talk with you today, and I'd like to further thank the leadership of AAAE for sponsoring the numerous classes, seminars, and other training opportunities that help improve safety at airports all across the country. I would also like to thank Mr. Thomas Zoeller, from AAAE who took the time to speak at our forum! I would be pleased to answer any questions you may have about our efforts in runway safety or other aspects of the Board's work.