475,000 Takeoffs and Landings a Year

The Summer Games will bring 4,000 additional aircraft to London’s airports. Find out what it takes to keep Heathrow running smoothly on a normal day.

Heathrow's new control tower is located near Terminal Three. The control room, mounted on a steel mast, is five stories high and weighs more than 1,000 tons. (Søren Geertsen)
Air & Space Magazine

(Continued from page 2)

“Most professionals want to behave ably,” says Mathewson, who finds himself part efficiency analyst and part psychologist. “You don’t need to force them. You just need to raise their awareness that this is an issue, and they can help.”
The airport spent about a half-million dollars building a temporary exit next to one closed for eight weeks of reconstruction. Otherwise airplanes would have had to coast 500 feet farther down the runway before turning off, which would slow the landing rate.

“This is the business of teasing the edges,” says Richard Smith, a lanky, intense man who helps plan the future of the airfield. He likens Heathrow to a giant aircraft carrier. When he started, after getting turned down for pilot training nearly 30 years ago, 900 airplanes were taking off and landing every day; now 1,370 do. He knows the angle of each taxiway, which affects which way airplanes can turn, which in turn affects how long they take to reach the gates. He knows which airplanes fit at which gates, and how juggling gates at the last second sends ground crews dashing through the airport.

In certain places, 747s park nose-out so their tails do not block signals from the instrument landing system. Workers are tearing down a few gates so the new double-deck A380, the world’s largest passenger airplane, has room to pass (see “Superduperjumbo,” June/July 2006). The airport is counting on the airplane to pack in more passengers. But air traffic controllers are starting to scream about all the construction.

“They have said to us, ‘We’re getting to the point we can’t maintain the movement rate, not because we can’t use the runway, but because we don’t have the taxiways,’ ” says Smith, racing around the airport in a white car with a flashing light on top. He eyes a taxiway that is a quilt of concrete patches. “The problem is keeping Heathrow going under all this pressure. We spend huge amounts of time and effort making sure this place doesn’t fall over, and it doesn’t happen by chance. It works because the place collectively works as a team, by design or by default. And it’s not all by design.”
An American airliner appears in the rear-view mirror: “I’ve got to keep an eye on that one,” Smith says. “I don’t want to get run over by a triple-7.” Computers match airplanes to gates, he says, but it’s not a simple process: Arab aircraft cannot be parked next to Israeli ones, for example.
Then he sees airplanes parked in a lineup of gates that causes him to chortle: American Airlines 777, United Airlines 777, American 777, United 777, and Iran Air 747. “Well, gee, Mr. Bush! Clearly one of the parameters in the computer is it’s okay to put the Iranians next to the Yanks,” Smith cackles. “I think that’s quite funny.”
On any given day, tomorrow at Heathrow has already started. Airplanes are on their way from Hong Kong and beyond, for an arrival the next morning. “Airlines have been told to slow up miles out because there’s no use getting here early if we have no bloody place to put them,” Smith says. It’s practical, and, as far as the passengers are concerned, “Will you notice if the airplane slows down 15 knots, or will you notice sitting on the ground for 20 minutes with the engines running?”
Once the airplanes have landed, Ian Watson juggles them, finding them places at one of Heathrow’s roughly 165 gates. The computer may plan out the day, but it can’t account for glitches—jetways break, airplanes are late, the weather is unpredictable. So Watson takes over where the computer leaves off, compensating for the unexpected. He works in a bunker-like building in the crook of two taxiways. The building would have a great view of passing airplanes if not for computer screens that block all the windows. Watson uses a joystick to scan every nook of the airport, working out which airplanes get to park at a gate, or pier. Since Heathrow has more airplanes than gates, some park out on the pavement and wait for buses to ferry passengers to terminals.
Neighborhood Relations
About a mile and a half from the end of Heathrow’s southern runway is the Hounslow Heath Infant School, a public preschool where cheery Kathryn Harper-Quinn is the head teacher. She loves airplanes. The sleek Concorde, which rocketed in and out of Heathrow until 2003, was “one of the most beautiful things I’ve ever seen,” she says. But the everyday aircraft, descending over the school at slightly less than one per minute, cost teachers roughly 10 seconds out of every minute of classroom time. Everybody stops talking because the noise drowns out anything they say.

“You have to time the ringing of the bell,” she says one summer morning. “If you ring it when an airplane goes over, nobody hears it.” The whirlwind-like vortex from a passing airplane shattered tiles on the roof of the school’s kitchen. Sometimes vortices suck the shingles off roofs like a vacuum. Heathrow confirmed 102 “vortex strikes” on nearby buildings in the last fiscal year. Whenever this happens, the airport sends workers out to the damaged properties to fasten each shingle down with metal clips.

While airplanes have grown quieter, the number of flights to and from Heathrow has nearly doubled in the last 25 years—like a shift, locals say, from an occasional truck passing your window to constant traffic.
Noise is loud enough to irritate at least 300,000 people, the government says. Studies in nearby neighborhoods have found the noise impairs schoolchildren’s reading comprehension and memory. In 2001 the European Court of Human Rights ruled that the rights of the airport’s neighbors to peaceful sleep had been violated. The ruling was later reversed, but the airport now offers neighbors up to about $24,000—depending on the value of their home—to move away.

Tension over airport noise, mounting for decades, has brought Heathrow under some of the tightest noise restrictions in the world. Pilots descend toward the airport on a smooth trajectory, rather than dropping in stair steps from one level altitude to the next. In the continuous-descent approach, as it’s known, pilots do not gun the engines to level off along the way, and airplanes remain farther above homes—cutting noise roughly in half. Unlike many U.S. airports, Heathrow is privately owned, and its noise strategies are distinctly free-market. The louder an airplane, the higher its landing fees.

Computers linked to air traffic control radar track each airplane, and pilots who do not follow the rules get a talking-to from airport managers. Microphones at the end of runways track noise, and each airplane that breaks the limits gets fined up to $2,000.

Rules tighten at night, when the noisiest aircraft are banned entirely: Only about 16 airplanes are permitted to land or take off between 11:30 p.m. and 6 a.m., and the noisier they are, the fewer are allowed. Sometimes early airplanes circle in the sky until the curfew lifts.
Manufacturers design airplanes with Heathrow in mind. Airbus worked over the engines and wings of its double-deck A380 to make sure it would meet Heathrow’s noise rules. Boeing guarantees its new 747-800 will fly quietly enough to be allowed in and out of Heathrow at night.

Airliners at Heathrow take off from only one runway while landing on the other, lending a semblance of order to the place. At 3 p.m. each day, they switch—landing on the one they took off from in the morning. It takes air traffic controllers about a half-hour to orchestrate the switch. With some exceptions, depending on the prevailing winds, it gives people living at each end of the runway half a day of relative peace and quiet.

About Michael Milstein

Michael Milstein is a freelance writer who specializes in science. He lives in Portland, Oregon.

Read more from this author

Comment on this Story

comments powered by Disqus