As it stands today, runway safety relies on simple trust and acknowledgment. There are no railway-style gates, stoplights or other mechanical means to stop a crew from errantly crossing a runway or taxiway. There are, however, standardized tarmac markings, signs and very specific protocols that all commercial pilots are familiar with.
Crews acknowledge "hold short" instructions that allow them to taxi up to, but not onto, an active runway. When cleared "into position and hold" (or, if overseas, "line up and wait") they may proceed onto the runway but are not yet authorized to take off. Finally comes "cleared for takeoff," meaning just what it says.
On arrival pilots are "cleared to land," meaning the plane is allowed to continue its approach and touch down without further communication. Implicitly, whether or not it's visible to the crew, the runway will be clear of other aircraft. (This generally happens around the time you hear the landing gear clunking into place. The "we've now been cleared to land" announcement commonly made by flight attendants is bogus; they haven't the slightest idea when the pilots are cleared to land.) During taxi in, pilots may be instructed to "hold short" of other runways. Each of these directives must be acknowledged using specific language -- basically, the crew reads back the exact instruction:
Control tower: "United 502, taxi into position and hold, runway one-six." Pilot: "Position and hold, runway one-six, United 502."
A truncated "Roger, 502" or other muddled reply will get the controller snapping back at you, asking for clarification.
Communication is sometimes hampered by radio congestion. Foreign crews with marginal English skills and the lack of standardized worldwide phraseology are also negative factors. But the premise is simple and extremely effective: You do not land on, depart from, taxi onto or otherwise cross a runway without explicit permission to do so. If you're at all unsure, don't do it.
Of course, this is only half of the picture. A pilot can do everything perfectly and still be victimized by a controller's error. To that end, advanced ground surveillance radar, which allows ATC to closely monitor airplanes -- and certain vehicles -- as they maneuver around the tarmac, is becoming increasingly common. Thus far, however, the FAA has not come up with a solution for the chronic understaffing found at many ATC facilities. Call me old-fashioned, but if the agency believes that high-tech radars and fancy lighting schemes can compensate for reduced manpower, it is probably, and perhaps dangerously, mistaken.
The trouble with, for instance, flashing lights or a highway-style traffic signal is that we might come to rely on them too thoroughly. As any number of motorists who've been broadsided at intersections know, putting your trust in a stoplight isn't enough. As a driver, I feel more comfortable at a four-way stop than at a crossing controlled by lights. Technology, for all its usefulness, isn't the solution. In the end, staying out of harm's way relies on basic vigilance and situational awareness.
A little-discussed aspect of this issue is the influx of thousands of extremely low-time pilots into the system. Entry-level qualifications at regional carriers have fallen sharply, putting new hires with fewer than 500 flight hours at the controls of $30 million R.J.s, flying into some of the most congested airports in the country. An acquaintance of mine was recently hired by one regional affiliate with 280 total hours. When I had that level of experience, I could not have fathomed the idea of working for an airline. He had never landed at a busy commercial airport in his life; his first day on the job began with a rush-hour trip into LaGuardia. As discussed in this column in December, even the lowest-time first officer is highly trained, and is always accompanied by a more experienced captain. Experience, per se, is not a good indicator of a pilot's potential for screwing up. But on some level this is one more risk factor.
Which is not to inspire undue worry or panic. Remember, close to 20,000 commercial flights operate daily in the United States, virtually all of them safely. I don't feel the current situation represents a crisis, or reveals any large-scale breakdown of the system. But even the strongest chain has its weakest link, and there's no harm in pointing that out -- or trying to make it stronger.
Incursions are still very rare, and I'll remind passengers that certain experiences shouldn't be construed as close calls. For example, you'll occasionally be on approach, close to the ground, when suddenly your plane accelerates and begins to climb away. The captain comes on and explains that traffic on the runway hadn't cleared yet. This is not the same thing as an incursion, and does not, except in highly extraordinary circumstances, propose that you were close to hitting another aircraft. Go-arounds are not near misses. That's what the spacing parameters are there for -- to prevent a near miss from happening.
Meanwhile, the FAA's most valuable contribution to the problem might be something it has already done: stirred up awareness. When it comes right down to it, the best way of preventing collisions is for pilots and controllers to always be conscious of their possibility.
Had those planes in Chicago not missed each other that night in 1999, it wouldn't have been the first time a pair of 747s met in disaster. Not to close on a morbid note, but I'll remind you that aviation's worst-ever catastrophe involved two 747s that never left the ground. It happened at Tenerife, in Spain's Canary Islands, in March 1977. An unlikely chain of events, capped by an overanxious captain who took off without permission, led to a foggy collision that killed 583 people. Two summers ago I spent an afternoon with Bob Bragg, the surviving copilot of the Pan American plane involved in the crash. Hearing Bragg's riveting firsthand account, described here, I reckon that the smartest thing the FAA could do is hire Bragg to travel around the country, sharing his story with every pilot and controller.
Do you have questions for Salon's aviation expert? Contact Patrick Smith through his Web site and look for answers in a future column.
About the writer
Patrick Smith is an airline pilot. His column is archived here.
Related Stories
Ask the pilot
Dangerous airlines, deadly airports, foggy landings and other hazards of flying: Sorting out facts from fancy.
Ask the pilot
Can someone with no flight training safely land an airliner? Plus: Pilotless planes, overpaid pilots and other aviation myths.
Ask the pilot
Facing a serious pilot shortage, airlines are hiring crew members with remarkably little experience. What does this mean for safety?
Story finder (3 ways to search Salon)
Salon Directory (browse by topic)