Retirement ceremony for Master Sgt. Katherine Johnson Published Sept. 22, 2009 VANCE AIR FORCE BASE, Okla. -- Congratulations and good luck Master Sgt. Katherine Johnson. Thank you for your service. Time in service: 21 years Retirement ceremony: At 2 p.m., Friday, Oct. 2, in the Professional Development Center, Bldg. 455. A reception will follow.