By SCOTT MCCARTNEY
The Wall Street Journal
US Airways Flight 27 was roaring down Runway 15R at Boston's Logan Airport when a pickup truck suddenly pulled into its path. The Phoenix-bound jet with 89 people on board lifted off just two seconds before possible collision, according to a Federal Aviation Administration investigation.
Look out the window of your next flight and you will likely see a lot more than big jets. Vehicles operate all around runways, from mowers to wildlife patrols, maintenance workers, runway inspectors and construction crews. During a snowstorm at a big airport, 40 vehicles may be out in the runway area. And any one of them could end up driving into the path of a jet.
A new ground-traffic program, developed partly in response to the 2009 Flight 27 close call, equips ground vehicles at Logan with identifying transmitters so they are easily seen and labeled on radar in the control tower.
These transmitters, a small part of the massive conversion of air-traffic control to digital technology, eventually will be rolled out at airports across the U.S. to cut the risk of collisions and improve efficiency for air-traffic controllers, acting Federal Aviation Administration chief Michael Huerta said.
"An airport is a complicated environment with a lot of players," Mr. Huerta said. "If you know what everything is, you can make a decision better."
"Runway incursions"—when a plane or vehicle mistakenly ends up in the path of an aircraft—have been a major safety focus at the FAA and pilot organizations for several years. The most serious—those requiring "extreme action" or having "significant potential" for collision—have fallen considerably, from 67 in 2000 to fewer than 10 a year lately, thanks to better signs and warning lights at runway entrances, new taxiways and other improvements. Yet the total number of incursions actually increased 21% in the past year. The number of vehicle-related incursions was up 9% last year to 199 from 183, according to FAA statistics.
Flight 27 startled airport managers at Logan who already had been working to reduce incursions. The Airbus A320 was on a normal takeoff roll at 6:36 a.m. on June 18, 2009, when the driver of a construction vehicle, mistakenly thinking that Runway 15R was closed, pulled out onto the surface. The jet pulled up normally, never seeing the truck. The FAA incident report said the closest proximity was 500 feet on the ground—a distance the jet would cover in about two seconds at takeoff speed of about 170 to 180 miles per hour.
"That was an eye-opener," said Vincent Cardillo, deputy director of airport operations for the Massachusetts Port Authority, known as Massport, which operates the airport.
After the Boston near-disaster, Massport overhauled procedures for ground vehicles mixing with planes in runway areas. The airport began studying ways for vehicles to be seen better in the control tower—a pressing issue at small, congested airports like Logan, where vehicles and planes operate in close proximity.
By placing "transponders"—6-inch-wide boxes mounted under dashboards that respond to radar with identifying information—in vehicles that drive across and around runways, the latest generation of ground radar can pick up trucks just like planes. In low visibility, the ground-radar display may be the only picture controllers have in the tower, 250 feet up. In any conditions, computers alert them to potential traffic conflicts and mistakes. Before controllers can reopen a runway or clear a plane to take off or land, they must ensure no mowers, plows or other vehicles are in the way.
"This takes you to the next level of safety," said Flavio Leo, Massport's deputy director of aviation planning and strategy.
To make the system work, the airport spent $600,000 and a lot of staff time on developing a new transponder that would work reliably in airport vehicles. As part of its joint effort with Massport, the FAA says it spent about $650,000, upgraded its ground radar at Logan, and tested transponders and systems at its Atlantic City, N.J., lab, among other services. ITT Exelis Inc. XLS +0.17% made applications and software for airport vehicles.
The system is part of the FAA's "NextGen" modernization, a multidecade, multibillion-dollar digital conversion designed to cut delays and improve safety.
An FAA spokeswoman said San Francisco, Denver and Chicago's O'Hare International Airport have expressed interest in the ground-traffic program, but there is no timeline for rolling out the system.
Eventually, pilots could have the same picture of ground vehicles on their screens and a system to warn them when a vehicle is on a runway they are using. Another idea in the works: have the radar turn on warning lights on runways to automatically alert pilots when vehicles encroach seconds before landing.
For now, the radar alone is a big improvement. In the Logan control tower, the ground-radar display showing aircraft in light green or yellow now tracks and labels pickups, snowplows and other vehicles in darker green. The pickup driven by the shift manager for airport operations is automatically tagged as BOSP25, for example, with a radio call sign of "Port 25."
Before the transponders, vehicles had to radio controllers to identify themselves. Controllers had to find the right blip on the ground-radar display and type in an identifying tag that sometimes dropped off the vehicle as it moved around. If the driver didn't call in, the controller might end up broadcasting requests for mystery vehicles to identify themselves. Now, the system is automatic and constant, and cuts down on both typing and radio transmissions so controllers can focus on planes.
"The objective is for these guys to be heads up and looking out the window," said Andy Hale, the FAA's tower manager in Boston, as he watched controllers direct takeoffs and landings on a recent day. "Anything that enhances our situational awareness is a bonus, and this definitely does that."
The system also could reduce delays, officials say, since controllers are able to reopen runways earlier when they know exactly where vehicles are.
Drivers get a copy of the radar display on iPads mounted in their vehicles, so they can see exactly where they are on the complex layout of taxiways and runways.
Massport has been testing the new system on nine vehicles for more than a year. About 70 vehicles will have it installed by the end of this month, including several snow plows. Each vehicle transponder costs about $6,000.
Logan has also undertaken a comprehensive program to cut down on runway incursions of all kinds.
The airport built a new taxiway between two heavily used runways so planes can pull off more easily after landing and avoid running into the parallel runway. Logan rebuilt some intersections where planes had a difficult time maneuvering and pilots occasionally got confused. The airport limited the number of people who could drive on the airport, forcing more to go with trained escorts. And it put extra checkpoints on the perimeter road around runways to remind drivers where they are by forcing them to stop and swipe their ID cards.
http://online.wsj.com
No comments:
Post a Comment