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

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 pilot of a light plane in a fatal flight that caused a security scare on June 4 when it flew over restricted airspace near Washington 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.