Helicopter Tail Rotor Strike from Firefighting Bucket

Helicopter Tail Rotor Strike from Firefighting Bucket

On 2 May 2017 Bell 206B3 N911GE, operated by the Marion County Sheriff’s Office as a public-use aircraft, sustained substantial damage during firefighting operations near Orange Springs, Florida. The pilot was seriously injured.

Wreckage of Bell 206B2 N911GE (Credit: Marion Sheriff County via NTSB)

Wreckage of Bell B206B3 N911GE (Credit: Marion Sheriff County via NTSB)

The pilot was using an under slung Bambi Bucket and had completed between 25 and 30 drops on the fire.  According to the US National Transportation Safety Board (NTSB) safety investigation report:

After refueling, he completed three or four additional drops and then filled and pulled the bucket from the water and immediately felt “a severely out of CG [center of gravity] condition to the right.” He assumed that the bucket cables were entangled in the right landing skid, so he released the water from the bucket. The condition persisted, so he rocked the helicopter to attempt to free the cable without success. He then released the cable with the cargo release button and heard the “clunk” sound typically heard when the bucket was released, but then he heard another “clunk.”

The helicopter then began to spin violently and after 4-6 rotations crashed into the water.  After the aircraft submerged, rolled right and came to rest the pilot “egressed through the left cockpit door and swam to the surface”. On reaching the surface he inflated his life jacket, swam to the water’s edge and used his personal mobile phone to call for help.

The NTSB investigation revealed:

Damage to the Skid (Credit NTSB)

Damage to the Skid (Credit NTSB)

…6-inch long cable marks on the right rear landing skid tube and a torsional fracture of the tail rotor short shaft.

Tail Rotor Damage (Credit: NTSB)

Tail Rotor Damage (Credit: NTSB)

Tail Rotor Damage (Credit: NTSB)

Tail Rotor Damage (Credit: NTSB)

TRDS

Fractured Tail Rotor Drive Shaft (Credit: via NTSB)

Based on the pilot’s statement, the cable marks likely occurred initially when a cable became entangled on the skid tube…

After releasing the bucket the tail rotor shaft fractured when the cable or bucket contacted the tail rotor.

Safety Resources

Just today, 1 December 2018, a firefighting Kamov  Ka-32T  crashed in Korea with the loss of one life while uplifting water, though as seen in the library footage below, that was likely by a suction system.

Other Ka-32s do use an under-slung bucket:

Also see our articles:

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