Syracuse, N.Y. — The U.S. Air Force’s “office in the sky” swooped into Syracuse Thursday for some practice touch-and-go landings, and it was hard to miss. The twin-engine C-40B jet — call sign Venus51 — flew out of Joint Base Andrews near Washington, D.C., Thursday morning and headed to Syracuse Hancock International Airport, where it performed a series of touch-and-go’s before returning to Andrews after noon, according to its flight track on the AirNav RadarBox website.