March 14, 2000

Pilots say air crisis a 'warning' But they insist that the problem in the skies over Philadelphia is not safety, but capacity.

By Henry J. Holcomb

INQUIRER STAFF WRITER The airline pilots association said that Friday's radar failure at Philadelphia International Airport offered a "scary warning" of crippling future delays if the nation's air traffic control system is not dramatically improved.

But there is little risk of a midair collision, even during a crisis such as Friday's, because commercial passenger aircraft are equipped with "so many redundancies" to track nearby planes, Capt. Paul McCarthy, safety chairman of the Air Line Pilots Association, said yesterday.

There is a looming capacity problem, McCarthy said, adding: "We've got to bring the U.S. air traffic control system into the 21st century. If we don't, we won't have the capacity the nation will need in the years just ahead."

The Federal Aviation Administration yesterday completed a preliminary investigation into what went wrong at 8:03 p.m. Friday, and also declared that there was no safety risk.

The problem on Friday was caused by failure of three circuit boards, Holly Baker, an FAA spokeswoman, said.

The backup system kicked in immediately, she said, enabling controllers to track the location of aircraft. But she said it was nearly a half hour before the alphanumeric displays that accompany each blip on the radar screens were restored.

So, controllers knew where the airplanes were, but did not know their speed, direction or altitude, she said.

As a result, they had to "slow the system down to preserve safety," delaying four arrivals and 36 departures for up to 45 minutes.

Baker said there had been no problems since Friday.

This failure, the fourth at the Philadelphia control tower in less than a year, left politicians seething.

U.S. Sen. Arlen Specter (R., Pa.) said the system "is antiquated . . . it is just a matter of time before something disastrous happens."

U.S. Rep. Robert Brady (D., Pa.) said the system "must be replaced. Our air traffic controllers shouldn't have to rely on a patchwork system. We can't keep having this happen. My two granddaughters are flying Thursday. We've got to straighten this thing out."

The pilots association and the FAA insisted yesterday that the issue is not safety, but capacity, or the number of planes the system can handle with its current technology.

McCarthy, the pilots association safety chairman, said everything on the ground could fail and pilots could still avert collisions - "there are so many redundancies built into the system."

He said the location of every aircraft within 40 miles of his plane is displayed on instruments that airliners are required to have.

"If an aircraft penetrates my safety shield, to use a 'Star Wars' term, its color changes on the display and an automated voice calls out 'Traffic, traffic,' " McCarthy said.

If the pilots of the two aircraft do nothing, their computers communicate and decide what to do, he said.

An automated voice tells one pilot to climb and the other to descend. This happens in time to require only a gentle maneuver - "the passengers won't know what has been done," McCarthy said.

A completely separate set of instruments keeps track of an airliner's location in relation to the ground and such obstructions as hills and radio towers, McCarthy said.

Carol Couchman, a technical officer for the pilots association and former air traffic controller, agreed. "There are so many systems to assure safety," she said.

But she and McCarthy said the United States was increasingly plagued by a patchwork system 20 years behind Europe's.

"Cleveland has one set of problems, New York has another. . . . Philadelphia suffers a severe capacity penalty because its air space lies under the New York City arrival and departure patterns," limiting the number of planes that can arrive and depart at peak hours, McCarthy said.

Unless the U.S. air traffic control system is upgraded into an integrated nationwide system, with reliable equipment and staffing, there won't be enough capacity to meet forecast demands, he said.

-- Martin Thompson (mthom1927@aol.com), March 14, 2000

Answers

Previous articles:

http://greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=002lrb

-- Martin Thompson (mthom1927@aol.com), March 14, 2000.

"So, controllers knew where the airplanes were, but did not know their speed, direction or altitude, she said."

I always thought that altitude was part of an aircraft's location, especially when you are talking about planes coming into and out of an airport. Silly me!

-- C Murray (celiaam@aol.com), March 14, 2000.

I listened to the FAA Y2K hearings on C-Span last summer. The FAA had not remediated computers or replaced majority of them. Something called windowing was used. Temporary fix within a certain time frame, giving FAA time to replace computers in the future. Not even 90 days into the year, and it looks like the time to replace all systems is now. And, this is just the FAA, wonder what other agencies loom to doom?

-- Ruth Angell (bar@bpsinet.com), March 14, 2000.

There is quite a bit in the archives concerning this problem. Got to Air transportation. Or start here:

http://greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=002DGr

-- Martin Thompson (mthom1927@aol.com), March 14, 2000.

The Airline pilot quoted is in error, or at least oversimplifying. I co-wrote the GAO report in 1989 which documented the fact that when similar errors happened in Dallas Ft Worth, there were a number of problems for the controllers, which impacted their ability to control traffic. If the screens are going blank, then the controllers are going bonkers, especially when there is significant traffic in the air (when breakdowns usually occur, due to capacity problems).

-- Bud Hamilton (budham@hotmail.com), March 16, 2000.