The skies above the Salt Lake International Airport have become so congested that the airport will soon be one of only 25 airports in the country to have its airspace strictly controlled by the airport's radar room.
After Nov. 16, air traffic controllers will have the authority to forbid any plane to enter the airspace surrounding the airport if the skies are already crowded.Planes flying through the valley west of I-15 must get radio permission from Salt Lake Approach to do so. The planes must also be equipped with transponders that automatically report the planes' altitudes to the radar screen at the airport.
The altitude-reporting transponders will make it easier for air controllers to keep airplanes a safe distance from each other.
While officials deny that the midair collision over Kearns 21/2 years ago triggered the new rules, others privately credit the tragedy for the stricter regulations.
Increased air traffic and passenger loads at the airport prompted the change, said Dan Piper, assistant air traffic manager at the airport tower.
After Nov. 16, the airspace surround the airport will be called a Terminal Control Area, and will be governed by the federal regulations set up for such areas.
For example, planes flying by instrument must stay 1 1/2 miles away from planes flown by visual lookout unless pilots of both planes have spotted each other, Piper said.
The Terminal Control Area will be a rectangle of sky over the valley roughly 50 miles long, 20 miles wide and 7,000 feet high, said Piper.
Work on upgrading the Salt Lake airspace began a few months after a SkyWest Metroliner collided with a Mooney in Kearns on Jan. 15, 1987.
The Metroliner was flying under instrument flight rules. The Mooney was flying by visual lookout. Salt Lake Approach did not alert either plane of the other's presence. The collision left 10 people dead.
While the new regulations are intended to make Salt Lake skies safer, there are no guarantees. "Everything is predicated on people following rules. It's just like driving on the highway," Piper said.
A Terminal Control Area probably would not have prevented the midair collision over Kearns. "My personal opinion is that no matter how many rules you make, you don't prevent pilot mistakes," said Phillip Ashbaker, director of aeronautics for the state of Utah.
Ashbaker cited midair collisions in Terminal Control Areas, particularly the one in November 1986 of a DC-9 and a Piper-Archer over Cerritos, Calif. The collision killed 82 people.
There are several similarities between the Kearns and Cerritos collisions.
In the Kearns collision, the pilot of the Mooney violated Airport Radar Service Area regulations by flying into the area without establishing radio contact with the tower, according to the findings of the National Transportation Safety Board.
In the Cerritos collision, the safety board concluded that pilot of the small plane also violated regulations by flying into the Terminal Control Area without getting permission from, or even establishing radio contact with San Diego Approach.
With the Terminal Control Area "you will still have the possibility of aircraft getting inside controlled areas that don't belong there," Ashbaker said. "To say that a TCA will fix all possibilities of a midair collision, no, it will not."
Plane owners who plan to fly within 30 miles of the airport, must carry Mode C transponders, which report the plane's altitude to radar. Depending upon the equipment already on the plane, the required modification can run anywhere from $200 to several thousand dollars.
The new Terminal Control Area boundaries leave a corridor east of I-15 for planes that don't want to fly through the TCA. When the skies over the airport are crowded, planes may be diverted to that narrow strip of sky. Small planes already commonly fly across the east side of the valley.