The United Launch Alliance's Atlas 5 rocket's next launch with the US Air Force's fifth Advanced Extremely High Frequency communications satellite, previously scheduled for Thursday, was postponed to July 9, to replace a defective battery in the vehicle.
In a Sunday statement, ULA stated that the launch was delayed due to a vehicle battery failure that was discovered during final processing.
The ULA crews at Cape Canaveral prepared for the launch on Thursday at 8:27 am EDT (1227 GMT). AEHF-5 spacecraft for secure communication between US military and president.
"The technical team needs extra time to complete the evaluation of the i ssue and replace the battery," ULA said in a statement.
A launch window for Atlas 5's earliest launch option on July 9th was not announced, but the window is expected to open at approximately 7:45 am EDT (1145 GMT).
The Atlas 5 rocket is fully assembled in the Vertical Integration Facility (VIF) on the Complex 41 launch pad of Cape Canaveral. Since the first stage of the Atlas 5 arrived at the VIF last month, workers have installed the Rocket's Centaur upper stage, five solid rocket boosters, and the Atlas 5's payload coverage on the AEHF 5 spacecraft.
The launch of the AEHF 5 satellite will follow the launch of four previous AEHF spacecraft in 2010, 2012, 2013 and 2018, all on Atlas 5 rockets. Atlas 5's Centaur upper stage will launch its RL10 engine thrice three times to place the AEHF-5 spacecraft in an elliptical "high-energy" geostationary orbit from 8,970 miles (14,435 kilometers) to 21,933 miles (35,298 kilometers) altitude with a tilt of 9.95 degrees.
The missile will launch the AEHF 5 spacecraft approximately 5 hours and 40 minutes after launch. The satellite's engine will direct the vehicle into a circular geostationary orbit over more than 35,000 kilometers across the equator, where AEHF 5 will integrate its predecessors into the secure communications network.
Following the launch of AEHF 5, ULA plans to begin stacking its next atlas 5 missiles within the VIF at Complex 41 for the first unmanned test flight of the Boeing CST-100 Starliner Crew Capsule scheduled for launch in September.
E-mail the author.
Follow Stephen Clark on Twitter: @ StephenClark1 .