The recent groundings of thousands of flights have raised flags about skipped airplane inspections and botched repairs to wiring.
But what really worries aviation specialists? Runway collisions.
“Where we are most vulnerable at this moment is on the ground,” the chairman of the National Transportation Safety Board, Mark V. Rosenker, said. “To me, this is the most dangerous aspect of flying.”
For the six-month period that ended March 30, there were 15 serious “runway incursions,” compared with eight in the period a year earlier. Another occurred at the Dallas-Fort Worth International Airport on April 6, one of the closest on record, when a tug operator pulling a Boeing 777 along a taxiway failed to stop at a runway as another plane was landing, missing the tug by about 25 feet.
The last airliner crash in the United States, a regional jet in Lexington, Ky., in August 2006, was a runway incursion because the crew tried to take off on the wrong runway.
The problem — defined broadly as the unauthorized presence of a plane, vehicle or pedestrian on a runway — continues despite efforts by the Federal Aviation Administration and airports to improve lighting and signs on the ground, to train pilots and to identify intersections that are particularly problematic. Everyone agrees the number is too large.
Runway collisions are caused almost entirely by human error. But they are still mostly preventable, because the risk could be substantially reduced with existing technology, ranging from paint on the pavement to electronic warning systems.
Some of the more sophisticated electronic systems are commercially available, but are not required by the FAA. And the most recent decision by the agency about a new generation of equipment for navigation and surveillance appears to delay the widespread adoption of in-cockpit warning technology by at least more than a decade.
Solving the runway incursion problem has been on the National Transportation Safety Board’s “most wanted list” of safety improvements since the list was created in 1990, and the board rates the FAA’s response as “unacceptable.”
The board recommended in 2000 that the FAA require a collision warning system that would alert crews directly, rather than alerting tower controllers, but the FAA has said the complexity and expense are too great.