To the earthbound, a clear sky over Lake Michigan appears endless and empty.
To the pilot of a small airplane, bouncing through that sky at 120 knots, that open vista is a three-dimensional puzzle.
There, by the city with the world’s busiest airport, the air is carved into dozens of invisible circles and slices–overlapping layer cakes of airspace that each carry their own responsibilities and risks.
Large planes are guided through those layers by air traffic controllers. With computer-aided radar, the controllers direct an ever-changing minuet of traffic, guiding airplanes with monotone radio messages of altitude and compass heading.
But in other circumstances and places–including the low altitudes near Meigs Field where two planes collided last Saturday, killing seven people–pilots don’t get that much help. They depend on what they see to keep them safe.
“You have to keep your eyes scanning . . . every square inch of glass in your airplane,” said Steve Applebaum of Berwyn, who flies small planes in and out of Meigs at least once a week. “If there is an airplane in your window and you can see movement, you’re OK.
“If it doesn’t move, it’s coming right at you. That’s the hardest thing to see–a fixed object.”
As investigators try to find and fit together the puzzle pieces that made up Saturday’s deadly crash, they are looking not only for what happened in the air, but also what happened in the minds of the two pilots and one controller involved–what they saw and heard, what they did not hear or see.
In the air around Meigs, there is plenty to see.
“If you can imagine being in the Sears Tower and looking out, flying through the area would be like magnifying that a thousand times,” said Mike Gaeta, a 28-year flying veteran who has often flown past Meigs, including Saturday.
When an airplane enters Meigs’ airspace, approximately five miles in any direction from the tower, from the ground to an altitude of 3,100 feet above sea level, the pilot is required to operate by what are called visual flight rules.
Under these regulations, the protocol used most frequently by small planes, it is the pilot’s responsibility to see and avoid other airplanes.
Here the dance becomes decidedly low-tech.
Pilots are supposed to radio Meigs tower–usually staffed by one controller, who depends on binoculars, cooperation and vigilance to do the job–before entering the airspace, and say what they plan to do.
The controller can give a pilot instructions, but neither is relying on the sophisticated electronics that help direct traffic at larger airports.
It’s common to find a half-dozen planes in Meigs’ airspace, and Applebaum said he has seen as many as 30 planes landing, taking off or flying through at the same time.
Most of those pilots are diligent. But particularly on a nice day, the stirring combination of lake and skyline can distract some fliers from their work.
“There are a lot of sightseers there, and a lot of Sunday drivers,” Applebaum said. “People are looking out the window, looking at the beaches, having a good time.”
Even at the modest airspeed of 120 knots (a little more than 130 m.p.h.), a pilot has less than 15 seconds to react to a plane that is a mile away, headed in the opposite direction at the same speed. Discounting 3 or 4 seconds for adjusting the plane’s controls, it leaves little cushion.
Pilots equate the experience to driving a car in fast-moving traffic, except that the third dimension–altitude–is also in play.
Investigators now believe that both aircraft in Saturday’s collision were descending. The Beechcraft Bonanza carrying three people had been cleared for landing and was last seen on a regional radar screen dropping below an altitude of 1,500 feet.
Wednesday, at a National Transportation Safety Board briefing, investigator Frank Gattolin disclosed that the Cessna carrying four young women also was losing altitude.
The Terminal Radar Approach Control based in Elgin, which covers the greater Chicago area, recorded the Cessna descending from 1,800 to 1,500 feet before it, too, dropped below the radar’s coverage. The collision is believed to have occurred several hundred feet below that.
Where airplanes’ paths seem likely to pass too close for safety, controllers try to warn and redirect pilots.
But at Meigs, controllers’ tools are limited to binoculars, a radio, telephones and a grease-pencil log of the planes in the air. With windows on all sides of the Meigs tower, controllers watch, use the radio and mark planes’ altitudes and courses on a large plastic board, using a special shorthand developed for the purpose.
Saturday’s crash lit a fire under an already warm debate about whether to add radar in the Meigs tower.
Radar would give controllers another significant tool, but it would be expensive, especially in light of the possibility that the airport will close in five years.
Lou Wipotnik of Mt. Prospect, named Flight Instructor of the Year in 1996 by the Federal Aviation Administration, said he believes Meigs should be equipped with radar.
“Everybody would like to see what is called a `bright scope,’ ” at Meigs, Wipotnik said. “It would be a monitor off of O’Hare approach control radar . . . so they can monitor the aircraft and their various positions. It would enhance safety.”
With or without radar, however, it falls to the pilots to see and avoid other airplanes.
In addition to the instruments inside the airplane that pilots must monitor, and whatever distractions there may be out the windows, fliers must also overcome the blind spots inherent in the design of their aircraft.
In the Cessna, which has a high wing over the top of the fuselage, the view above and behind the cockpit is obstructed. In the Beechcraft, a low-wing aircraft, the view below and behind the cockpit is blocked.
Gattolin said Wednesday that investigators are now looking at whether the particular combination of blind spots in those two planes contributed to the accident.
But several pilots said the blind spots, too, are part of their responsibility.
By briefly dipping or raising the nose of the plane, the pilot can view what is blocked by the wings, and that should be a regular part of the surveillance, Applebaum explained.
Investigators, who hope to figure out whether those or other problems figured into Saturday’s crash, continue to gather evidence.
On Wednesday, investigators interviewed the controller on duty at the time of the collision.
Meanwhile, three-foot waves forced divers to abandon their search for parts of the planes for the second day in a row. About 80 percent of the Beechcraft has been recovered, along with about 60 percent of the Cessna, Gattolin reported.
Investigators hope to finish reconstruction of the planes by Friday morning.
