Jets Had Adequate Separation

A Delta pilot aborted a landing Tuesday at Logan International Airport in Boston, after an onboard traffic collision avoidance system alarm sounded. At 4:37 pm, the TCAS system onboard the Boeing 757 detected the presence of a Delta Connection regional jet operated by Chautauqua Airlines. Both planes were descending over Hingham Bay toward the airport in gusty winds.

Radar data indicates the 757 was about 100 feet above a Delta Connection regional jet -- but the jets had approximately 3,500 feet of horizontal separation, FAA spokesman Jim Peters said Thursday.

"There was no potential for a collision," Peters said.

After performing the go-around, the Delta pilot radioed that the other jet was "just about 100 feet below us," according to Boston's Patriot Ledger.

Controllers warned both pilots to keep each other in sight during their descents toward nearly parallel runways. Both pilots acknowledged the order, Peters said.

It was unlikely the pilots mistook another jet in the area for the one they were instructed to keep in sight, Peters said.

The Atlanta, GA-based airline is investigating the incident.

"Anything that's not a normal routine flight operation, we would have a report from our pilots and launch an investigation and get everyone's side of the story," spokeswoman Gina Loughlin said.

The landing patterns used Tuesday are a new configuration, since the opening of a new runway at Logan in November 2006.

When crosswinds gust to 10 knots or greater, smaller aircraft can use Runway 14/32. Larger aircraft make staggered landings on the nearly parallel Runway 33L only when clear conditions prevail, to enable pilots to properly monitor the position of other aircraft.

FMI: www.delta.com