The Black Hawk helicopter that crashed in Leesburg killing four onboard was conducting a test flight with a newly installed piece of firefighting equipment when a piece came off and swung into the blades, the preliminary crash report from the National Transportation Safety Board shows.
The Black Hawk helicopter crashed during a training exercise May 25 near the Leesburg airport. Leesburg city officials said all four crew members died. Their bodies were recovered in the wreckage but officials have yet to release their names.
The aircraft was registered to Brainerd Helicopters Inc./Firehawk Helicopters, which contracts with the federal government for firefighting and other services.
The Federal Aviation Administration and the NTSB are investigating the crash. On Wednesday, the NTSB released its aviation accident preliminary report.
Previously the FAA said the aircraft was conducting a water drop exercise and lost control of the bucket, causing the rotor section to separate. The chopper went down in a wooded area near the airport and caught fire.
According to the NTSB document, a new water tank and snorkel were recently installed on the helicopter for firefighting operations. Snorkels are hoses that allow hovering helicopters to suck loads of water out of natural and man-made sources, according to the Associated Press.
After several days of ground testing and calibration, the chopper took its first flight on May 25 with the new equipment.
Witnesses told NTSB investigators the helicopter made six passes by the air hangar conducting water drops from a nearby lake before the snorkel came loose. Two employees of Brainerd Helicopters Inc./Firehawk Helicopters noticed and attempted to alert the pilot, according to the report.
One employee said he called the Leesburg air traffic control and told the controller to ask the pilot to slow down and land immediately. Before contact was made, the helicopter began gaining altitude and the witness said the snorkel was “violently” swinging. He then heard a loud bang, which the witness believed was the snorkel hitting the main rotor blades.
The chopper then started to spin and fell below the tree line, according to the NTSB report.
Another employee for the helicopter operator said she saw several passes before she noticed the snorkel swinging and coming close to hitting the main rotor blades. The employee also noted that the water being dropped from the tank was “very dirty.”
She told investigators she immediately started waving her arms at the pilot in an attempt to alert him to the problem. She said as the chopper transitioned to forward flight she ran alongside and continued waving her arms to no avail. The witness said she heard a load bang and saw multiple rotor blades separate and hit the tail of the aircraft.
NTSB investigators wrote the helicopter came to rest on its left side and the rail rotor was about 78 feet north of the main crash site. The newly installed water tank and snorkel assembly were found on the west edge of runway 3 at the airport.
The majority of the helicopter was destroyed in the post-crash fire, according to the report.
A final report by the NTSB will be released after the investigation is complete.