Officials have recovered the cockpit voice recorder – also known as the black box – from the helicopter involved in the plane crash that killed 67 people at Ronald Reagan Washington National Airport on Wednesday.
Emergency responders are planning to ramp up operations over the weekend to recover the debris from the site.
There were 64 passengers aboard an American Airlines flight when it collided with an Army Black Hawk helicopter carrying three soldiers.
The Federal Aviation Administration (FAA) has since restricted helicopter traffic around the airport after concerns from officials about overcrowding in the airspace overhead.
As of Friday, 28 people from the crash had been identified and 41 bodies had been recovered from the water.
The rest of the bodies will not be found until officials are able to hoist the plane off the riverbed, officials have said.
Investigators recovered the black boxes from the wreckage of the passenger plane the day after the collision.
After soaking those black boxes and extracting the moisture from them, they will be able to get data from the recorders “very soon”, National Transportation Safety Board member Todd Inman told reporters on Friday evening.
“We just have to work through a number of steps,” Mr Inman said.
NTSB members said they still do not know the cause of the collision.
Mr Inman said the “main lifting” of the salvage operations, which will be carried out by the US Navy, will begin on Saturday.
Parts of the aircraft need to be removed from the water before divers can go back in.
Authorities plan on mapping the debris in the river so they can better understand how the aircraft responded to the collision.
Work to remove large segments of the aircraft from the water by crane starts on Sunday and will continue throughout the week, said Mr Inman.
Over 500 people have been working around the clock at the site of the crash in the Potomac River, Washington DC fire chief John Donnelly said.
Mr Inman was asked about reports that one air traffic controller was managing both control for helicopters and airplanes flying in the area
He did not comment on specifics, but said officials plan to examine the controller’s behaviour over the past several weeks and in particular, the 72 hours before the crash.
“Obviously we’ll be looking at not only staffing that day…[but also] how many people, what job functions they’ve done, are they being combined.”
The Air Traffic Control group is still conducting interviews.
Mr Inman was also asked whether his team is in contact with the White House.
President Donald Trump has suggested without evidence that the helicopter involved in the crash “was flying too high”.
Recordings of air traffic control conversations published online suggested that a controller tried to warn the helicopter about the American Airlines plane in the seconds before the collision.
The helicopter pilot appeared to respond to confirm they were aware of the plane, but moments later the two aircraft collided.
Trump has also said suggested that diversity hiring at the FAA may have led to safety issues.
“Our job is to find the facts,” Mr Inman said. “More importantly, our job is to make sure this tragedy doesn’t happen again – regardless of what anyone may be saying.”
