TDRS-K Satellite Cleared for Launch

by

UPDATED Jan. 29 10:24 a.m. EDT

WASHINGTON — The first of a new generation of NASA telecommunications relay satellites has been cleared for a Jan. 30 launch aboard a United Launch Alliance (ULA) Atlas 5 rocket from Cape Canaveral Air Force Station, Fla., agency managers said at a Jan. 28 press conference.

The Boeing-built Tracking and Data Relay Satellite (TDRS)-K was declared ready to fly in a Jan. 28 launch readiness review, which followed a Jan. 25 mission rehearsal at the Cape, Jeffrey Gramling, NASA’s project manager, said during a press conference at the Kennedy Space Center, which is co-located with Cape Canaveral Air Force Station.

TDRS-K had been penciled in for launch Jan. 29, but mission managers had to delay for a day to replace the rocket’s ordnance remote control assembly, which allows controllers to destroy the vehicle if the launch goes awry. That component “has been removed, replaced and retested,” NASA spokesman George Diller said.

TDRS-K is the first of NASA’s third-generation TDRS satellites and the 11th TDRS satellite ever built. There are now six active satellites and two backups in the geosynchronous constellation, which NASA and other agencies use to communicate with spacecraft in Earth orbit.

Boeing Space and Intelligence Systems, Seal Beach, Calif., is building the latest TDRS satellites for NASA under a $700 million fixed-price contract awarded in 2007. The contract called for Boeing to build TDRS-K and TDRS-L, with options for an additional two satellites. In 2011, NASA picked up a $289 million option for TDRS-M.

NASA spokesman Dewayne Washington said Jan. 29 that NASA not yet exercised an option for TDRS-N.

“NASA is conducting the annual reliability analysis of the TDRS operational fleet and TDRS-K, TDRS-L and TDRS-M to determine the fleet robustness in 2020 and beyond,” Brown wrote in a Jan. 29 email. “NASA is working to extend the TDRS-N option thru the end of fiscal year 2013 to assure the TDRS-N option can be exercised, if necessary.”

Under the terms of Boeing’s 2007 contract, the TDRS-N option expired Nov. 30.

Three of the TDRS satellites now in service, TDRS-H, TDRS-I and TDRS-J, also were built by Boeing. The multi-user TDRS constellation also supports the U.S. Department of Defense, including the Missile Defense Agency, the National Science Foundation and others.

The oldest TDRS satellite still in operation, TDRS-3 built by Northrop Grumman Aerospace of Los Angeles, was launched in 1988 by the space shuttle.

“We’re well beyond design life,” Gramling said of the first generation TDRS satellites during the Jan. 28 news conference.

TDRS-K was supposed to have launched last year. A December launch date slipped into January due to investigations into the underperformance of the upper stage engine on a ULA Delta 4 rocket during an otherwise successful military launch Oct. 4. Delta 4 and Atlas 5 upper stages use different variants of the Pratt & Whitney Rocketdyne-built RL-10.

Denver-based ULA and the U.S. Air Force are still pursuing separate investigations of the anomaly. Officials say the anomaly was caused by a fuel leak in the interior thrust chamber of the RL-10, but the root cause has yet to be determined.

The Delta 4 remains grounded, and every Atlas 5 launch since the Oct. 4 incident has gone off only after the rocket received extra prelaunch scrutiny at the pad.