WASHINGTON (CNN) — Beginning in mid-May, pilots who intrude into restricted airspace over the nation’s capital will be warned by pulsating red and green laser beams, part of a government effort to prevent a terrorist attack.
The U.S. military will activate the ground-based lasers whenever unauthorized or unresponsive aircraft enter the restricted zone, a huge swath of airspace surrounding the region’s three major airports.
The bright laser beams, which flash red-red-green, are easily seen, even during daylight or in a sea of city lights. But because the beams are directional, they rarely will be seen by other aircraft or by the public, except in hazy conditions. The laser beams can be seen 15 to 20 miles away, authorities said, except in cloudy conditions.
The lasers are harmless, say authorities, who are quick to distinguish them from the high-intensity laser pointers that have vexed some pilots in recent months.
«This is good laser, if you will,» said U.S. Air Force Col. Ed Daniel of the North American Aerospace Defense Command. «It is very eye safe.»
Private pilots who have been briefed on the new system generally support it, but said they don’t know if the lasers will work under all conditions. «If you are flying west in the afternoon and the sun is directly in your eyes, it will be very difficult to see anything else,» said Fayek Zabaneh.
While NORAD would still prepare to launch jet fighters during each intrusion, a quick response by an errant pilot might keep the fighters on the ground, saving the tens of thousands of dollars it costs each time jets are scrambled.
Hundreds of incursions per year
Incursions into the restricted space are common. NORAD officials said there are typically two or three incursions a day, usually by pilots not familiar with the restrictions or who stray from their intended flight paths.
The most notable incident occurred during President Reagan’s funeral activities last summer when a jet carrying Kentucky Gov. Ernie Fletcher entered the airspace with a broken transponder, prompting the evacuation of the U.S. Capitol.
Following the September 11, 2001, terrorist attacks, the government severely restricted air traffic in the region. It established an Air Defense Identification Zone — an area consisting of a 30-mile diameter circle around Reagan Washington National Airport and 22-mile circles around Dulles and Baltimore-Washington international airports.
Pilots in the airspace must communicate with air traffic controllers, transmit a four-digit identifier with their transponders and take other measures to let controllers know their identity and intentions.
Restrictions are more severe in a 15.75-mile inner circle called the Flight Restricted Zone.
«There are so many high-value targets in this area. It is the center of government. We need to do everything we can to protect it,» Daniel said.
Red-red-green sequence
If an errant plane cannot be contacted by radio, authorities would attempt to get the pilot’s attention by aiming the lasers and flashing the rapid red-red-green signal — colors chosen because they are easily seen and a sequence not otherwise used in aviation.
NORAD says that whenever it uses the lasers, it will notify the Federal Aviation Administration and others through the Domestic Events Network, an open phone line that connects government agencies charged with protecting Washington.
Authorities declined to say how many ground-based lasers there are, nor did they reveal their locations, although that may eventually become apparent to residents.
Officials refused to give the total cost of the system, but said individual, costs for unmanned laser sites totaled $500,000.
NORAD developed the system in two years, constructing it from off-the-shelf technology. There are no plans to put similar systems in other cities, although it could be considered for locations such as the presidential retreat at Camp David.
NORAD said that both military and independent medical personnel have validated the safety of the system.
The military says it considered using spotlights to warn planes, but that lasers are more discrete and, because they can be aimed at a specific aircraft, less likely to cause confusion to other planes.
Pilots have been concerned about a spate of incidents involving people who have pointed lasers at airlines.
The Federal Aviation Administration has announced new protocols, requiring pilots to report laser lights to air traffic controllers, who will warn nearby pilots and notify police.