Thursday's incident at LaGuardia airport that saw a jet skid off the runway is a reminder that air safety is an everyday challenge.
In 2014, the Federal Aviation Administration identified 1,264 runway "incursions." This year is on pace to beat that number.
The FAA defines incursions as "any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle or person on the protected area of a surface designated for the landing and take-off of aircraft." They could be as simple as a plane taking the wrong turn and going on the wrong runway.
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Through the first five months of fiscal year 2015, the FAA has identified 513 runway incursions, compared with 469 last year.
At that pace, the total would be 1,383 for 2015, or 45 percent higher than in 2011.
Not all incursions are the same
To be sure, not every incursion is the same. Some are more dangerous than others, but all of them are a problem, especially if the number keeps increasing each year. Here are the three definitions listed by the FAA.
Operational Incidents: "Action of an Air Traffic Controller that results in: Less than required minimum separation between 2 or more aircraft, or between an aircraft and obstacles, (vehicles, equipment, personnel on runways) or clearing an aircraft to take off or land on a closed runway."
Pilot Deviations: "Action of a pilot that violates any Federal Aviation Regulation. Example: a pilot crosses a runway without a clearance while en route to an airport gate."
Vehicle/Pedestrian Deviations: "Pedestrians or vehicles entering any portion of the airport movement areas (runways/taxiways) without authorization from air traffic control."