Ernest A. Mettenet Jr., vice chairman of Hercules Aerospace Co., will retire effective Feb. 1, but he plans to stay in the Salt Lake area.

With nearly 40 years of service, Mettenet is credited with leading the company through it greatest growth period when it broadened its position in high-performance strategic missile motors, expanded into large solid propellant space motors and became the domestic leader in graphite materials and graphite composite structures."Utah has done a great deal for me personally and for Hercules. I've developed a great appreciation for this area and its people and intend to remain here and make a contribution to its growth," he said.

Mettenet was responsible for the design and construction of the only automated robotic propulsion plant in the aerospace industry at the $150 million Bacchus West facility in western Salt Lake County. The facility is entering its second generation and a $145 million expansion will be completed later this year.

During his tenure, the Hercules rocket motor case-winding facility at Clearfield was expanded to the largest, most modern facility of its type in the free world. The company also added the plant at McGregor, Texas, to its aerospace group.

Mettenet joined Hercules at the home office in Wilmington, Del., as a design and field engineer. He assisted with construction of a polyolefin plant in Parlin, N.J., and later became production engineering superintendent.