WASHINGTON — Orbital ATK of Dulles, Virginia, has named Scott Lehr to succeed veteran and former astronaut Ronald Grabe as president of its rocket-making Flight Systems Group, the company announced June 11.

The appointment is effective July 1, Orbital ATK said. Scott has served as senior vice president of the group and Grabe’s deputy since the former Orbital Sciences Corp. closed its acquisition of ATK Aerospace Systems in February.

Before the merger, Lehr served for 31 years with ATK and a predecessor company, most recently as general manager of ATK’s Commercial and Defense Propulsion Systems Division, Orbital ATK said.

Grabe will stay on with the Flight Systems Group, which makes rockets, missiles and missile defense systems, in an advisory capacity.