Minotaur rocket booked for space-based range demo
BY STEPHEN CLARK
Posted: April 4, 2012
The U.S. Air Force has purchased a Minotaur 1 rocket for a mission in 2013 to prove less-costly, next-generation range tracking, safety and communications systems to streamline future launch operations.
The Operationally Responsive Space office, a Defense Department program conceived to demonstrate space systems on leaner budgets and rapid schedules, is sponsoring the ORS 3 mission, which is scheduled to launch in the summer of 2013 from Wallops Island, Va.
Orbital Sciences Corp., the Minotaur 1's prime contractor, announced the launch contract April 3. Financial terms were not disclosed.
"If you go down to one of the big launch ranges, we use radar tracking systems, we use a beacon, and we use optical trackers to track the rocket through its flight path," said Peter Wegner, director of the ORS office at Kirtland Air Force Base, N.M. "And if it gets outside of the pre-approved window then we send a flight termination command."
The Air Force is migrating toward using GPS receivers on rockets to avoid the overhead costs of legacy radar trackers. The next step will be for launch vehicles to track themselves, comparing real-time GPS positions to predicted values, and issuing a command to destroy itself if it veers too far from its planned flight path.
Today, Air Force range safety officials monitor U.S. launches and would manually issue a destruct command if necessary.
"We're working really hard on what we call space-based range systems," Wegner said. "The idea behind space-based range is you literally take all that range infrastructure, which is time-consuming and costly, try to streamline it and put it on the rocket."
"ORS 3 is a test of many of those technologies," Wegner said. "The reason I was really interested in funding that mission is it takes us from flying these things on sounding rockets to putting them on a real orbital rocket like a Minotaur 1."
A GPS metric tracking system flew aboard an Atlas 5 rocket for the first time Feb. 24 in a military satellite launch from Cape Canaveral, Fla. Rocket launchings from Cape Canaveral and Vandenberg Air Force Base, Calif., require multiple sources of real-time tracking data, including radar, optical and GPS, to ensure the flight does not threaten populated areas.
Officials expect the ORS 3 launch to go forward despite the proposed closing of the Operationally Responsive Space office in President Barack Obama's fiscal year 2013 budget request. The spending plan, which needs the approval of Congress, would transfer the ORS initiative to the Space and Missile Systems Center, which manages Air Force space procurement.
Wegner said the ORS 3 launch also offers capacity to launch up to 17 satellites for government and university customers. The largest of the Minotaur's payloads will be STPSat 3, a host satellite for several military experiments, according to Wegner.
Ball Aerospace and Technologies Corp. in Boulder, Colo., completed the build-up of the 396-pound STPSat 3 spacecraft last year. The Air Force was considering commercial launch opportunities before selecting the Minotaur 1's ORS 3 mission for a lift into orbit.
STPSat 3 will be the second flight of the Space Test Program-Standard Interface Vehicle, a common spacecraft bus for small technology demonstration and military research missions.
The solid-fueled Minotaur 1 launcher will also haul 16 CubeSat payloads into orbit for government and institutional customers.
According to Wegner, the Minotaur 1 launch will be conducted as a commercial flight.
"We're going after a commercial acquisition approach for a Minotaur," Wegner said. "We're trying to push hard on different cost models from a business perspective."
The Federal Aviation Administration will license the launch commercially instead of through Defense Department oversight.
"That's saving us quite a bit of money, maybe double-digit millions [of dollars] in cost savings," Wegner said.
The ORS 3 mission will mark the 11th launch of a Minotaur 1 vehicle, a four-stage booster powered by decommissioned Minuteman missile motors and heritage systems from the air-launched Pegasus rocket.
It will be the fifth Minotaur 1 flight from the Mid-Atlantic Regional Spaceport, a state-run launch facility located at NASA's Wallops Flight Facility on Virginia's Eastern Shore.
"We are very pleased to continue to provide cost-effective military space missions for the U.S. Air Force," said Ron Grabe, Orbital's executive vice president and general manager of its launch systems group. "For the past 15 years, the Minotaur program has provided highly reliable and affordable launchers that combine government-owned propulsion systems with commercial rocket technology to support Department of Defense and other U.S. government space missions."
An enhanced Minotaur 5 rocket, propelled by more powerful Peacekeeper missile motors, is also due for launch in mid-2013 from Wallops with NASA's LADEE mission to probe the tenuous lunar atmosphere.
The LADEE and ORS 3 launches can occur about 60 days apart, and officials have not formally decided which mission will fly first.