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Northrop Grumman Proposes Rapid Response Launch Vehicle
by Staff Writers
Colorado Springs CO (SPX) Apr 05, 2006
Northrop Grumman officials said Tuesday the company is developing a reusable unmanned space vehicle that could deliver satellites or special-purpose payloads into space in as little as 48 hours after receiving a launch request.
The new concept, called a Hybrid Launch Vehicle, also could reduce mission costs by about two-thirds compared to using an expendable rocket.
“The HLV concept offers the Defense Department a relatively simple, affordable way to put standardized, tactical satellites into orbit quickly after receiving a request for support,” said Dennis Poulos, Northrop Grumman’s HLV project manager.
The HLV concept would combine a reusable, airplane-like - but unpiloted - first stage with expendable upper stages. Launched vertically, the vehicle’s winged first stage would boost the upper stages to speeds approaching Mach 7, before releasing them at an altitude of approximately 150,000 feet.
The upper stages lift the payload into orbit or deliver a conventional weapon to a distant target, while the first stage returns to its home base automatically. The HLV first stage would use a rocket engine during the boost portion of its mission, and an integrated set of air-breathing jet engines for the return flight.
“The reusable nature of the first stage reduces the cost of producing, testing and storing new hardware for each flight,” Poulos said. “It also allows the launch vehicle to be inspected in a hangar like an aircraft, mated with a new upper stage and returned to the launch pad in about 48 hours or less.”
Northrop Grumman is defining the architecture for an operational version of the HLV under a 20-month, $3.0 million studies-and-analysis contract with the Air Force’s Space & Missile Systems Center at Los Angeles Air Force Base. The contract includes a base amount of $1.5 million over 14 months, with an option for an additional $1.5 million over an additional six months.
Under the contract, the company will also define a concept for a subscale demonstrator version of the launch system, and the infrastructure required to execute a demonstration program. The subscale launch system, if developed, would be used to demonstrate the technologies, processes and key attributes of an operational system.
The studies-and-analysis phase is the first step in a process the company said could lead to the selection of two contract teams to develop preliminary designs for the HLV. At the end of the design competition, the Air Force may select a single team to develop and produce a demonstration model HLV.
As envisioned, the HLV would include both medium-lift and heavy lift configurations, both of which could lift payloads into conventional low-Earth orbit, polar low-Earth orbit or geosynchronous-transfer orbit, depending on the mission. The Air Force has set threshold payload requirements and desired payload requirements for each type of orbit.
As part of its current contract, the Northrop Grumman team will analyze the relative costs to lift different size payloads, and then base its operational system architecture on the HLV design that offers the Air Force the best value.