JACKSONVILLE, Fla. — Federal investigators continue to work to find out what caused a plane, carrying 143 passengers and crew, to skid off a runway in North Florida.

Authorities say the Boeing 737 that skid off a runaway at a military base in Florida and ended up in a river has had no prior accidents.

The military chartered plane landed hard in a thunderstorm Friday night at Naval Air Station Jacksonville, carrying passengers from Guantanamo Bay, Cuba. The aircraft rolled off the runway and into the St. Johns River.

Everyone onboard survived and there were no serious injuries. Four pets on board the plane did not survive, officials said.

The flight data record has been sent to Washington for analysis by the National Transportation Safety Board. NTSB investigators will look at everything from the condition of the plane, to the environment and the pilots as they search for clues into the crash.

The Miami Air Boeing 737 built in 2001 is still sitting in the St. Johns River after sliding off the runway Friday. 

According to the NTSB Go Team which arrived on scene Saturday afternoon with about 16 crew members to conduct the investigation say they were able to recover the flight data recorder, which will give them the airspeed and altitude. 

A "last minute" change

Federal investigators say pilots of a chartered jet that ran into a river at a Florida military base made a last-minute change to the runway where they would make a landing.

NTSB Vice Chairman Bruce Landsberg said at a Sunday presser that the pilots on the plane requested the change shortly before landing at Naval Air Station Jacksonville Friday night.

Landsberg says the 9,000-foot-long runway was essentially limited to 7,800 feet since there was wire set up to recover Navy aircraft in instances they couldn't land on a carrier during training.

Landsberg says investigators at this point don't know why the pilots wanted the change.

Conerns were also raised surrounding the impact on the St. Johns River. NTSB officials say the 1,200 pounds of fuel on board is being containted to the immediate area.

Update on the pets

Once most of the passengers were on land, Naval Air Station Jacksonville commanding officer says the search turned to locating the pets onboard. Investigators said they checked twice for animals. 

Navy divers went into the cargo hold Sunday, where the pets were located, but according to NAS Jacksonville, four of the pets aboard did not survive. 

In a Facebook post, NAS Jacksonville said "every possible avenue to rescue these animals was pursued following the incident."

"So at the moment of impact I went forward and I had my seat beat on, hit my head on the top of the roof," said passenger Darwing Silva. "I kind of landed and I just remember feeling water come falling from above. I had water like on my on my feet, like my ankle high or what not."

NTSB is also requesting witness video of the incident. They advised anyone who may have recorded the incident to send it to witness@ntsb.gov.

According to NTSB it's unclear when they will be able to remove the plane. 

Information from the Associated Press was used in this report.