(CNN)The National Transportation Safety Board on Monday released a preliminary report on a deadly helicopter crash in New York's East River.
NTSB releases preliminary report on New York City helicopter crash
Five people died when the Liberty Helicopters chopper crashed on March 11. The passengers had chartered the trip for a private photo shoot.
The preliminary report does not provide analysis and does not discuss probable cause.
"The information in the report is preliminary and subject to change as the NTSB's investigation progresses," the NTSB said.
Key points from the report include:
When the the helicopter crashed, the five passengers drowned because they were unable to break free from harnesses meant to prevent them from falling out.
The pilot told NTSB investigators he provided a safety briefing to the passengers before takeoff. The briefing included a description of how to use a cutting tool to cut their restraints, the pilot said.
During the flight, passengers could turn to face out of the helicopter's open sides to take photos.
When the helicopter was flying along the east side of Central Park, "the front seat passenger turned sideways, slid across the double bench seat toward the pilot, leaned back, and extended his feet to take a photograph of his feet outside the helicopter."
The pilot "observed engine pressure and fuel pressure warning lights and believed he had experienced an engine failure," the report says.
As the pilot made his way to the East River to execute an emergency landing, "he reached down for the emergency fuel shutoff lever, he realized that it was in the off position. He noted that a portion of the front seat passenger's tether was underneath the lever."
The pilot attempted to restart the engine as the helicopter fell toward the river, but the engine "wasn't spooling up fast enough," leading him to turn off the emergency fuel lever again.
The helicopter quickly began to fill with water as it landed in the river. The pilot attempted to unscrew the carabiner of the front seat passenger, but then "decided to egress the helicopter."
An NTSB examination of the helicopter found the engine was not impacted by "oil or fuel leaks, fire, or uncontainment," according to the report.
"The fuel flow control lever was found in the off position. The fuel shutoff lever was found in the open position."
The restraint system for passengers was manufacturer-installed, but the harness system for the passengers was not installed by the helicopter manufacturer, the report states.
The harness system was comprised of off-the-shelf components consisting of a nylon fall-protection harness that was attached at the occupants' back by a locking carabiner to a lanyard, the report says. This allowed the passengers to move in the chopper.
A "small pouch was attached to the harness and contained a cutting tool."
The March 11 crash was the deadliest crash involving a national doors-off helicopter tour, and Liberty Helicopters' third crash in the past 11 years.
Liberty Helicopters posted a statement on its website after the crash, saying it was "focused on supporting the families affected by this tragic accident and on fully cooperating with the FAA and NTSB investigations."
In the wake of the crash, the NTSB issued an urgent safety recommendation calling for the Federal Aviation Administration to ban commercial flights' use of harness systems that don't allow for easy release during emergencies.
The FAA issued an order suspending "doors off" flights involving "restraints that cannot be released quickly in an emergency." But NTSB Chairman Robert L. Sumwalt said "the FAA has not outlined how or when they plan to take action."
"Definitive action needs to be taken," he said.