Unique Crush Horns Help Ford F-150 Ace Crash Tests

Ford Motor Co.'s aluminum-intensive F-150 pickup truck has earned the highest possible five-star ratings in government front, side and overall crash results.

The previous all-steel F-150 earned a four-star overall rating, three stars for frontal impact performance and five stars for side impact protection from the National Highway Traffic Safety Administration.

The improved ratings put the redesigned F-150 on par with the rival Chevrolet Silverado pickup.

The improved results are due mainly to increased use of high-strength steel in the frame. Ford says the truck's chassis contains 77% high-strength steel compared with 23% for the previous model. The structure is 60 lbs lighter in spite of an additional crossmember for greater side impact strength.

Ford attributes much of the improved frontal impact performance to hydroformed front crush horns that help manage crash energy and keep it from affecting the passenger compartment. The horns act as forward extensions of the frame.

Conventional rectangular crush horns have walls that can collapse in an unstable buckle. Ford's tapered horns have a plus-shaped cross section and several "trigger holes" that ensure a more stable collapse. The design can absorb twice the crush force of a square cross section horn over a given crush distance, according to the company.