WASHINGTON — The launch of NASA’s next Tracking and Data Relay Satellite (TDRS) has slipped to mid-January from late December due to cascading range delays associated with the ongoing investigation of an upper-stage engine anomaly during the Oct. 4 launch of the Air Force’s GPS 2F-3 satellite, an agency spokesman said.

“A request for a Jan. 18 TDRS-K launch date has been submitted by United Launch Alliance to the 45th Space Wing and it’s pending approval from the Eastern Range,” NASA spokesman Trent Perrotto wrote in a Nov. 1 email to SpaceNews.

When it does launch, the Boeing-built TDRS-K will replenish the geosynchronous satellite constellation NASA maintains to communicate with objects in low Earth orbit. TDRS-K is now in line for launch at Cape Canaveral Air Force Station, Fla., behind the Air Force’s X-37B winged space drone, also built by Boeing. The X-37B launch was recently pushed to Nov. 27 from Oct. 25 to accommodate United Launch Alliance’s (ULA) ongoing investigation of the GPS 2F-3 launch anomaly.

GPS 2F-3 launched aboard a Delta 4 rocket. TDRS-K and X-37B will both launch on an Atlas 5. Both ULA rockets use a variant of Pratt & Whitney Rocketdyne’s RL-10 cryogenic engine to power their second stages. On the GPS 2F-3 launch, ULA detected lower-than-expected thrust levels in the Delta 4 upper stage, which prompted a parallel series of industry- and government-led investigations.

Boeing Defense, Space & Security, El Segundo, Calif., is building TDRS-K and its sister satellite, TDRS-L, under a $700 million fixed-price NASA contract awarded in 2007. Last year, NASA picked up a $289 million option in Boeing’s contract that calls for the company to build a third TDRS satellite, TDRS-M. An option for Boeing to build TDRS-N is set to expire Nov. 30.

Boeing said in an Oct. 29 press release that TDRS-K will be delivered for launch by the end of the year. TDRS-L is slated for launch in 2014 aboard an Atlas 5, according to Boeing’s press release.

Besides NASA, the TDRS constellation is frequently used by the U.S. Department of Defense, Missile Defense Agency, National Science Foundation and others. It comprises eight satellites, including six active satellites and two backups.

Dan Leone is the NASA reporter for SpaceNews, where he also covers other civilian-run U.S. government space programs and a growing number of entrepreneurial space companies. He joined SpaceNews in 2011.Dan earned a bachelor's degree in public communications...