Ask the pilot

How can an airplane, loaded with every high-tech gizmo imaginable, accidentally land at the wrong airport?

By Patrick Smith

Jul 2, 2004 | On Saturday, June 19, Northwest Airlines flight 1152, an Airbus A319 en route from Minneapolis to Rapid City, S.D., carrying 117 passengers and five crew members, touched down smoothly just after noon. Trouble was, they weren't in Rapid City. They'd arrived at Ellsworth Air Force Base, a military airfield six miles from the Rapid City Regional Airport.

Remarkable as it might sound, the unannounced landing -- which, as my mailbox burstingly attests, did not go unnoticed by news-savvy readers of Salon -- was not unprecedented. Years ago a Western Airlines 737 pulled a similar maneuver in Wyoming, and in 1995 a DC-10 touched down in Brussels instead of Frankfurt. A regional turboprop once confused the northern Maine outposts of Caribou and Presque Isle, while more recently, in January of this year, a US Airways Express flight bound for State College, Penn., ended up in Philipsburg, Penn.

If you're like me, you wouldn't know the difference between State College and Philipsburg if you were sitting in the lobby of City Hall, but the idea of highly trained aircrews with troves of technology at their behest landing astray sounds, I'll agree, amusing, quaint and even patently ridiculous. The letters I've received in the past several days are equally aghast, incredulous and cackling.

How does it happen? Anticipated by some is an answer of tangible malfunction: improperly keyed coordinates or a navigational computer gone crazy. Others suspect a more visceral, seat-of-the-pants explanation: a tired crew mixing up a pair of similar-looking runways.

After the Ellsworth incident, an Air Force spokeswoman reminded the dumbstruck news media that the crew's intended runway at Rapid City airport is "just over the hill" from Ellsworth. Implication: Pilots find their airport the way a lost motorist finds his way home -- second hill on the left, slight bank over the lake, watch for the farmhouse. Comments like these entice you to miss the big picture, in this case the vast context of the airspace system. I'm betting you don't want a dissertation on the innards of instrument approaches or a glossary of air traffic control vernacular, but the complexities of even the most ordinary good-weather landings are a bit more involved than lazy pilots craning their necks and saying, "Yeah, that looks like the right place, let's give it a try."

In addition to whatever human errors catalyze such events, weather and air traffic control, to name two other factors, can lend a hand in getting from point A to, as it were, point C. In the case of that DC-10 finding its way to Belgium instead of Germany, a confusing string of foul-ups caused controllers essentially to lead the plane astray. By the time the crew realized it was being vectored to the wrong country, they decided to land at Brussels rather than have to recalculate fuel reserves and orchestrate a last-second re-routing. In the end, it was safer to land in Brussels than Frankfurt.

At the same time, yes, pilots cleared for what we call a "visual approach," a procedure used with fair routine when sky conditions permit, will merely eyeball an airport through the windshield and report "field in sight," to air traffic control.

Descending toward Rapid City, the Northwest crew was flying a so-called VOR (very high frequency omnidirectional range) approach, a fair weather, non-precision-instrument procedure designed to guide aircraft toward the general vicinity of the runway, if not to the very threshold as with more accurate ILS (instrument landing system) approaches. Sixteen miles out, they'd intercepted the inbound course and began tracking it toward the airport. Emerging below a layer of clouds, they identified what was believed to be the correct runway and configured their jet for landing. What they'd seen, of course, was Ellsworth, its runway sharing an almost identical alignment with the intended strip at Rapid City, still about six miles away.

The carrier refuses to comment on who or what may have been responsible for the Ellsworth touchdown, and is keeping mum on everything from the pilots' names to their levels of experience. This is neither surprising nor unfair, and it's any investigator's policy to refrain from passing judgment when events are fresh and particulars still unknown. This is a business where the determined causes of accidents and incidents rarely conform to the earliest suppositions and theories.

Next Page: This screw-up can't be blamed on the technology...

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