A New York City sightseeing helicopter that crashed into the Hudson River, killing all six aboard—including a Spanish family of five—had a history of mechanical issues, including transmission problems months prior.

The Bell206L-4 aircraft, operated by New York Helicopter, was built in 2004 and had over 12,700 flight hours.

Investigators are probing maintenance records, pilot experience, and recent FAA safety directives related to rotor blade and tail rotor issues.

The chopper broke apart midair 25 minutes into its flight, the New York Post has reported.

The cause remains unknown, with missing rotor parts still being recovered.

Written by B.C. Begley