Investigators examining the fatal crash of a Shorts 330 freighter in Charleston have disclosed that the aircraft was not carrying either a flight-data or cockpit-voice recorder.
Neither instrument was required to be installed on the aircraft, which crashed at the city's Yeager airport on 5 May.
The Shorts 330 had been conducting an approach to runway 05 following a service, flight 2Q1260, from Louisville.
National Transportation Safety Board investigator Bill English says the Air Cargo Carriers aircraft had been banked to the left when it struck the runway, some 340ft after the threshold.
The angle of bank has yet to be determined but the Shorts 330 is a high-wing, twin-engined design.
It subsequently veered off the runway, tracing a course some 40° left of the runway heading, before coming to rest in thick brush around 100ft down a hillside some 650ft from the initial impact point. There was no post-impact fire.
English says no distress call was transmitted. He adds that the inquiry has access to a video recording of the event, which is under review, but that the Shorts 330 was carrying neither a flight-data nor cockpit-voice recorder.
He adds that an initial examination shows there are "no other electronic devices" on board the aircraft which would have recorded "significant" information about the flight.
Neither crew member on the aircraft survived the crash.
Meteorological data for the airport at the time, around 06:55, shows that it was shrouded by low cloud, overcast at 500ft, although visibility for the airport itself was 10 statute miles (16km). Valley fog was present in the area.
English has not confirmed the type of approach has been disclosed, beyond stating that it was "from the west", but air traffic communication records captured by the LiveATC site suggest the aircraft had been cleared for a VOR-A approach.
This approach involves following a course from the west of the airport, descending on a heading of 084°, before turning left to align with the runway.
English says the recovery of the aircraft wreckage has been "slow going" but that documentation of the position of cockpit controls is being carried out, and the inquiry has accounted for all major components of the aircraft.
NTSB investigators will be supported by the UK's Air Accidents Investigation Branch as well as Bombardier, which previously acquired the original aircraft manufacturer, Shorts of Northern Ireland.