Retirement ceremony for Lt. Col. Darren Siegersma Published Jan. 7, 2010 VANCE AIR FORCE BASE, Okla. -- Congratulations and good luck on your retirement Lt. Col. Darren Siegersma. Thank you for your service. Time in service: 21 years Retirement ceremony: 8 a.m., Friday, Jan. 8, in the 5th Flying Training Squadron conference room, Bldg. 690. A reception will follow the ceremony in the conference room.