Private plane that caused DC scare did not respond minutes into fatal flight

By David Shepardson

WASHINGTON (Reuters) - The pilot of a light private plane that caused a security scare on June 4 when it flew over restricted airspace near Washington before crashing, killing all aboard, did not respond to air traffic control minutes into the flight, investigators said on Wednesday.

The National Transportation Safety Board (NTSB) said 12 minutes into the flight that killed four, a controller cleared the Cessna 560 to 34,000 feet and the pilot read back the clearance.

Three minutes later, the controller amended the altitude clearance but the pilot did not respond and made no further radio transmissions.

The NTSB said the cockpit voice recorder has not been recovered. The plane crashed in a mountainous wooded area of southwest Virginia after taking off from Elizabethton, Tennessee at 1:13 p.m. leaving wreckage that was extremely fragmented, scattered around a main crater showing evidence of a post-impact fire.

The Department of Defense scrambled F-16 fighter jets, which created a sonic boom over the U.S. capital as they pursued the Cessna.

The pilot killed was Jeff Hefner, a retired Southwest Airlines captain and pilots union board member with 34,500 flight hours. The daughter of the plane's owner, his granddaughter and a nanny were also killed.

The Federal Aviation Administration (FAA) said it reported the pilot's failure to respond to controllers to the domestic events network that includes military, security and law enforcement agencies at around 1:36 p.m., but the plane was not intercepted until 3:20 p.m.

The NTSB said the Cessna 560 after flying past Long Island MacArthur Airport in New York continued southwest on a ground track of about 240 degrees and showed little deviation or altitude change until 3:22 p.m., when it entered a rapidly descending right spiral descent into terrain.

The crash was reminiscent of other incidents involving unresponsive pilots.

Golfer Payne Stewart died in 1999 along with four others after the aircraft he was in flew thousands of miles with the pilot and passengers unresponsive. The plane eventually crashed in South Dakota with no survivors.

In the case of Stewart's flight, the plane lost cabin pressure, causing the occupants to lose consciousness because of oxygen deprivation.

(Reporting by David Shepardson; Editing by Chris Reese and Bill Berkrot)