A graphic shows where United Airlines Flight 169 clipped a 15-foot-high light post along the New Jersey Turnpike as it was approaching Newark Liberty International Airport on May 3. Image courtesy National Transportation Safety Board

June 4 (UPI) -- The pilots of a United Airlines flight that flew low enough to shear off a light pole on the New Jersey Turnpike as it landed in May knew they were flying too low but were unable to compensate in time, a preliminary report stated Thursday.

The first officer of United Airlines Flight 169 from Venice, Italy, to Newark Liberty International Airport called out, "Hey you are slow," just before the Boeing B767-424ER clipped a light pole along the turnpike while approaching Newark's runway 29, according to the National Transportation Safety Board's initial report of the May 3 accident.

The incident resulted in debris from the light pole impacting a tractor-trailer traveling southbound on the turnpike.

The aircraft was just 19 feet above the busy highway when it connected with the 15-foot-high light post.