Too early for panic in air-traffic control tower scenario

As we near the date when some air traffic control towers will close, the claims of unsafe skies are gaining volume. Most of it, though, remains guesswork.

In a story filed today, the Associated Press headlines “Planned closure of nearly 240 air traffic control towers will strip away layer of safety.

The planned shutdown of nearly 240 air traffic control towers across the country under federal budget cuts will strip away an extra layer of safety during takeoffs and landings, leaving pilots to manage the most critical stages of flight on their own.

The towers slated to close are at smaller airports with lighter traffic, and all pilots are trained to land without help by communicating among themselves on a common radio frequency. But airport directors and pilots say there is little doubt the removal of that second pair of eyes on the ground increases risk and will slow the progress that has made the U.S. air system the safest in the world.

I’ve already written extensively on the likely effect of the planned closures because of “the sequester,” so I won’t bother repeating how the system won’t collapse, at least based on the scant information those who say it will have provided so far.

There’s no question that having another set of eyes watching airport operations — even at a dull airport — adds a level of safety; that’s simple logic. But the AP story overstates the threat a bit.

Here’s one description of the comments of the only pilot the AP put in its piece. He flies a small plane:

Chicago pilot Robert McKenzie, who has a commercial license but primarily flies a small Cessna, has a lot of experience landing at smaller airports without control towers.

Doing so involves a lot more concentration, he said. Pilots have to watch for other aircraft, take note of weather conditions, look for debris on runways and make calls over the radio — all while operating their own plane.

A little more concentration isn’t a bad thing. The FAA has been trying to get pilots to add it for years. And, in fact, controllers do not absolve the pilot from the responsibility to see and avoid other aircraft. That’s the pilot’s responsibility. Any pilot who supplies less concentration because there’s a controller in a tower, is doing it wrong in the first place. Winds, weather, stuff on the runway, and talking on the radio? Pilots have to do that whether there’s a control tower or not.

It’s also worth noting that equipment inside even small airplanes is vastly different from just a few years ago. Many, including the one I built, are equipped with passive traffic warning systems. And, although it won’t do any good for this sequester crisis, in a few years, every plane — even the small ones — will have the same image of air traffic in front of them that air traffic controllers have on their screens on the ground.

Most troubling, he said, would be the loss of towers at airports such as Springfield and Santa Fe, which are used by a mix of small private planes and larger passenger aircraft that often converge on airfields at different speeds and using different procedures. Controllers keep those planes safely separated and sequenced for landings.

True, addressed in my previous post on the subject, and not that troubling. But let’s take the afternoon rush hour at Sante Fe, as an example. Here’s what it looked like this afternoon, courtesy of flight aware. The traffic destined for Santa Fe is depicted in light blue. Yes, there was only one.

sante_fe_flightaware.jpg


It’s a SkyWest flight which, at this particular position, probably wasn’t being controlled by Sante Fe tower at all. For most of the flight, it was probably under the watchful eyes of Albuquerque Center, an FAA facility. True, the image is a little misleading because only traffic being controlled in the air traffic control system is depicted.

Over the course of 4 hours today, Sante Fe tower handled 11 flights.

This does bring up, however, one problem with taking away the tower. If there are instrument conditions, controllers taking over for a closed Sante Fe tower would be allowed to send a flight into Santa Fe one at a time, keeping any other flights out of the same airspace. But that’s unlikely to be a significant problem, because Sante Fe doesn’t get that much traffic to begin with, which is why its tower might be among those closed.

But that clearly is going to be a problem at busier airports — Santa Monica, CA., comes to mind — in that there will be some delays for pilots under the so called “one in-one out” policy. But the whole idea of that is safety and separation

In addition to round-the-clock tower closures, overnight shifts could be eliminated at 72 control facilities, including at much larger airports such as Midway, which sees an average of 50 flights daily between 10 p.m. and 7 a.m., nearly all of them passenger flights operated by carriers that include Southwest and Delta.

That raises the possibility that full-size jetliners could be landing there without any help from controllers.

Any help? A “full-size” jetliner is getting help from controllers right up until the time the controller instructs them to “contact the tower,” usually fairly close to the airport. A jetliner would not be “flying blind” into Midway. There are no overnight departures from Midway. Still, it’s hard to see the FAA closing the Midway tower unless the politics of the situation required things to hurt a little more than they otherwise would.

Meanwhile, up in Milwaukee, the news that the tower there could be closed overnight was met with the shrug of the shoulders by the airport manager.

“We don’t have any regularly scheduled airline flights from 11 p.m. to 5 a.m.,” he told the local AP bureau.

Hundreds of small airports around the country routinely operate without controllers, using procedures in place since the earliest days of aviation. Pilots are trained to watch for other aircraft and announce their position over the radio during approaches, landings and takeoffs.

But past crashes, however rare, have exposed weaknesses in that system.

On Nov. 19, 1996, a 19-seat United Express flight landing in Quincy, Ill., collided with another twin-engine turboprop that was taking off. They slammed into each other at the intersection of two runways, killing all 14 people aboard the two planes.

The National Transportation Safety Board concluded the probable cause was a failure of the pilots in the outbound flight to monitor the radio frequency for air traffic and to properly scan for other planes.

“If a tower was there, it’s highly likely that that accident would have been prevented,” said Hanna, who became director of the Quincy airport about two years after the crash and before moving to the job in Springfield.

It’s hard to argue with that. And it sounds simplistic to say “mistakes happen” but they do. They happened over the skies of downtown Saint Paul in 1992 when two planes, under the direction of a tower controller, collided and crashed near the old Gillette plant. They happened in Lexington, KY., in 2006 when a controller didn’t notice the plane he was directing took off from the wrong runway and crashed. They happened when controllers in Minneapolis accidentally put an airliner and a cargo plane on a collision course a few years ago. And they happened when things were so quiet overnight in Washington DC’s tower a few years ago, that the controller nodded off.

But citing those as an example of a control-tower system not working is as inaccurate as citing a 1996 crash at an airport as an example that untowered airports are unsafe.

To be fair, tower controllers do a fine job and serve a valuable function. For the sake of safety, of course it’s better to have them working than furloughed. But in this political chess game of sequester, it’s also important to take a deep breath and assess the extent to which each move inflicts damage.

And to that extent, it’s impossible to say what the overall effect is going to be until the FAA releases a staffing plan for all controllers in the system, and provides us with details on how the workload is going to be divided among those still employed.