Aviation Experts Worry About Aircraft Mishaps on the Ground

July 15, 2011 — -- With Thursday's collision of two commercial passenger aircraft on a runway at Boston's Logan International Airport in which the wing tip of a jumbo jet was sliced apart and the tail of the regional plane was badly mangled, aviation experts worry about the potential dangers that lurk on the runways of the nation's busiest airports.

Three months ago at New York's JFK airport, the wing of a giant Airbus clipped the tail of a regional jet, causing the smaller aircraft to spin like a top.

Ground mishaps are a major safety fret, and the Federal Aviation Administration has forced airports to improve the markings on runways and taxiways to help pilots stay on track. Although the FAA said serious runway incidents dropped 90 percent in the past decade, any close call can become potentially catastrophic.

In 2010, there were more than 900 runway incursions, which occur when planes get too close.

Six were considered of the most serious type -- down from 12 in 2009.

Runway incursion numbers include commercial and general aviation flights. Here are the airports that have experienced the most serious types of incursions.

Charleston AFB/International Airport, South Carolina

Chino Airport, California

Garden City Regional, Kansas

William P Hobby Airport, Houston, Texas

Livermore Municipal, California

Phoenix Sky Harbor International, Arizona

ABC's Lisa Stark and Matt Hosford contributed to this story.