Investigators say bad maintenance practices led to a 2017 plane crash that killed 15 marines — three of them with ties to the Hudson Valley and a Navy corpsman. 

A report from the U.S. Marines says consistent errors at Warner Robins Air Logistic Complex in Georgia, caused crews to miss corrosion on a deteriorating propeller blade of a C-130-T aircraft. 

The report says the corroded propeller was overlooked during a 2011 overhaul, leading it to snap off while the crew was flying over Mississippi in July of last year. 

Among the local servicemen who were killed in that crash: 34-year old Gunnery Sergeant Mark Hopkins of New Windsor, 46-year old Gunnery Sergeant Brendan Johnson of Fishkill, and 26-year-old Sergeant Owen Lennon of Rockland County, who was based out of Newburgh.

Also included in the report, Marine investigators say Stewart Air National Guard Base did not do enough to inspect propeller blades or track maintenance records. 

The report says Stewart was supposed to inspect planes that did not fly for more than eight weeks, but did not perform that inspection. 

Since then, the Navy grounded its fleet of C-130-Ts until propellers are replaced. Congress has appropriated $121 million to complete that work.

The report says the Air Force has agreed to adopt the Navy’s procedures for all propellers.