The National Transportation Safety Board says that they have determined what caused a tourist helicopter to crash into the East River, killing five people on board.

The NTSB released its report on the March 2018 crash Friday. The detailed report states that the main reason that the helicopter crashed was that a tether on a passenger’s harness became caught on a fuel shut-off lever. This caused the helicopter to lose power and fall into the river.

The crash happened on March 18, 2018, around 7 p.m. The passengers were on a 30-minute flight to give tourists a chance to take photos of New York City. The helicopter did not have doors.

The chopper’s slow descent into the East River was caught on video. The pilot, who survived the crash, had time to call “Mayday.”

The NTSB says on-board video recovered from the crash shows the passenger in the front seat, who was intoxicated, tried to adjust his seat and had his harness-tether inadvertently attach to the fuel shutoff lever on the floor. It pulled up and the engine stalled.

In a statement, the NTSB says, "...each time he leaned back, the tail of the tether attached to the back of his harness hung down loosely near the helicopter's floor-mounted controls."

Video shows the pilot trying to restart the engine, but the helicopter was too low, so he releases the floats.

The NTSB then says, "The helicopter's floats did not fully inflate, and the helicopter rolled right in the water and became fully inverted and submerged about 11 seconds after it touched down."

The passengers were unable to get out due to the unique nature of their harnesses. This particular helicopter had a tether and harness system that allows passengers to hang their legs out while in flight.

The report says the "harness/tether system, each of which was equipped with locking carabiners and an ineffective cutting tool, during an emergency requiring a rapid egress."

According to the transcript, one of the last things heard in the recording was a passenger asking, “How do I cut this?” while in the water.

The NTSB says the landing impact was survivable and no one had any visible blunt force trauma. The victims drowned.