Wednesday, November 21, 2007

Improved Airspace Management

The upcoming Thanksgiving holiday season prompted the President last week to reduce projected travel delays by allowing civilian airliners to use military air routes. The military routes are along the Eastern Seaboard (from Florida to Maine) creating a “Thanksgiving express lane” according to White House spokeswoman Dana Perino. The President was prompted to take this unusual action in part because of the extremely high percentage of delays encountered at Kennedy and LaGuardia airports. The on-time arrivals at the country’s two most congested airports were less than 61 percent. The nature of the air traffic control system is such that a delay at a single large airport has a cascading effect throughout the rest of the country. The expected number of travelers for this Thanksgiving will be around 27 million despite increases in fuel and airfares.

The reaction by the President has been applauded by the airlines but really fails at creating a long-term solution to the problem. By adding civilian aircraft to military air routes, military aircraft responding to emergencies alerts will have to exercise additional caution in executing their missions. Military controllers will have to spend additional time and effort identifying aircraft that may be transiting military airspace. Military training missions may potentially be delayed or curtailed during the holiday season. None of these situations enhances the security of the homeland. The increased volume of air traffic is being created without a corresponding increase in the ability to safely monitor and track these aircraft. Additionally, any military aircraft responding to potential attacks or threats will have to waste precious time avoiding any civilian airliners traveling along one of their routes.

All of this could be palatable IF the lack of airspace were the real cause of the problem. Civilian airspace is managed by the Federal Aviation Administration (FAA) which uses radar to observe and control civilian aircraft. Radar technology was first introduced by the British during World War II when it was discovered that radio signals could be bounced off of enemy aircraft. The bounced radio signals could be used to determine the location and heading of these aircraft. The basics of radar technology have remained the same despite improved technology. Early radar used for air traffic control would sweep (a term used to describe the rotational speed of the radar antenna) every 10 seconds. Approach radars sweep is every 5 seconds. With a modern jet airliner traveling at over 400 knots, and flight data for the radar updating only every 10 seconds, it becomes necessary to maintain a large separation between aircraft. Most civilian aircraft traveling under radar control must maintain a minimum horizontal separation of 2 nautical miles AND a minimum vertical separation of 5,000 feet. A near miss is anytime two aircraft come closer either vertically (altitude) or horizontally (distance) than these minimums.

The radar for controlling US airspace is woefully outdated. The radar system in place is pretty much the same system that has been in place since the 1960s. Aircraft are not truly controlled via radar either, aircraft are managed by their transponders. Transponders transmit a unique four digit signal (along with altimeter information) and are used in both tracking as well as collision avoidance. Newer satellite based technology exists which would give pilots far more accurate flight data than is presently available through radar and transponders. Safe distances between aircraft could be reduced as the satellite information would be constantly updated in real-time. However, Global Positioning Satellite (GPS) technology is expensive and would require a major retrofit of both FAA control centers as well as the cockpits of airliners.

Instead of meaningful dialog about ways to fund a replacement to the antiquated radar system, we hear about how airlines are increasing staff availability. Instead of partnering with our allies on retrofitting cockpits with GPS technology, we see the FAA posting more data about flight delays. There is even talk of a congestion pricing plan to discourage travel at peak hours. None of these “strategies” deals with the heart of the matter and more importantly none of the proposed measures does anything to increase security of the homeland. If airliners switched to GPS, it would not only reduce the amount of congestion in the airspace but it would also give military aircraft a tremendous advantage in tracking hijacked aircraft. Air routes could be used more efficiently and congestion could be quickly routed around delays or weather.

GPS is only part of the solution. The United States has not built a major airport since Denver International Airport opened in 1994. As of the time of this writing, no major airports are planned for the future. The increased amount of air travel creates not only congestion but huge crowds of people that could be attacked while waiting for their aircraft to arrive or depart. It wouldn’t take much, a fuel truck crashing through the main terminal or someone infected with a communicable disease (smallpox) walking around the awaiting passengers. The damage from an attack would be increase many fold by people attempting to flee from the area of attack. The attack would create huge delays as the effects of the attack cascade throughout the country. Multiple delays would be encountered and thousands more passengers would be stranded. The U.S. needs to create a strategic plan for addressing the major causes of air traffic delays and stop wasting time tracking symptomatic data points. Unchecked, the problem is not only one of inconvenience but one that also increases our vulnerability to another terrorist attack.

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