The Flight to Orbit
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There are numerous ways to get there— Around the Corner Th As then–US Space Command chief from rocket The Gen. Howell M. Estes III said to launch to space defense writers just before his re- tirement in August, “This is going maneuver to come along a lot quicker than we vehicles—and the think it is. ... We tend to think this stuff is way out there in the future, Air Force is but it’s right around the corner.” keeping its Flight The Air Force and NASA have divided the task of providing the options open. US government with a means of reliable, low-cost transportation to Earth orbit. The Air Force, with the largest immediate need, is heading to up the effort to revamp the Expend- to able Launch Vehicles now used to loft military and other government satellites. Called the Evolved ELV, this program is focused on derivatives of existing rockets. Competitors have been invited to redesign or value- engineer their proven boosters with new materials and technologies to provide reliable launch services at a he Air Force would like to go Orbit far lower price than today’s bench- back and forth to Earth orbit as bit mark of around $10,000 a pound to T O easily as it goes back and forth to Low Earth Orbit. The reasoning is 30,000 feet—routinely, reliably, and that an “evolved”—rather than an relatively cheaply. Such a capability all-new—vehicle will yield cost sav- goes hand in hand with being a true ings while reducing technical risk. “aerospace” force but is one which By John A. Tirpak, Senior Editor The goal is to reduce launch costs has long eluded a hardware solution. by at least 25 percent; industry Concepts such as the X-20 Dyna-Soar leaders are shooting for a cut of 50 of the 1960s and the X-30 National percent or more. The Air Force wants Aerospace Plane of the 1980s and a family of launch vehicles, scaled early 1990s reached beyond the to fit medium and heavy payloads technological grasp of their times. headed for LEO or Geosynchronous The space shuttle, while a formidable that both help reach orbit and slow Transfer Orbit. technical feat, has never lived up to descent. Many involve international In addition, USAF wants to “stan- the twice-monthly launch sched ule partnerships, particularly with Rus- dardize the interfaces” between or cost originally envisioned for it. sian outfits, but all emphasize reuse rockets and satellites, so any US All this may soon change. As the of all or most of the system, with an military satellite can be carried by demand for both commercial and eye toward becoming a space-age the launchers available. This will military satellites multiplies almost version of today’s overnight package increase flexibility and eliminate the exponentially, more than two dozen companies. possibility that the entire military private and government projects are Even if only a fraction of the new space effort could be shut down if a under way to try to meet the cor- concepts work out, access to space particular kind of vehicle developed responding need for inexpensive will broaden and the cost of getting a flaw that grounded it. The EELV launch services. One concept calls there will drop significantly. One program also calls for most of the for winged vehicles to be towed to industry official made the analogy processing of rockets to take place altitude, then released for a rocket- between today’s rush to build cheap off-pad, freeing the launchpads— powered flight to orbit. Another launchers to the barnstorming days which are in limited supply—to be anticipates a midflight air refueling of aviation, which paved the way for used as much as possible for launch before the final ascent. Still another an explosion of new machines and and not be tied up waiting for one. envisions employing giant rotors new applications. While the Air Force originally AIR FORCE Magazine / November 1998 41 of the next decade. The VentureStar Ever since the Space Age will take off vertically, using the began, the Air Force has liquid hydrogen and liquid oxygen wanted a craft that could in its vast internal fuel tanks, orbit, quickly get to orbit and then return to a runway landing. It can land like an airplane. This be flown autonomously, remotely, drawing of the Martin SV-5D, an unmanned or by an onboard crew. lifting body tested in the It’s an ambitious undertaking. To 1960s, was the pre-cursor reduce risk and prove the technolo- to the X-24A, a manned gies involved, a half-scale demon- vehicle flight-tested from 1969 to 1971. USAF and strator called the X-33 is being built NASA flew various lifting and will fly next year on suborbital body concepts, but they flights of up to Mach 15. The main proved too technically thing to be proven with the X-33 is ambitious for the time. that its power plant—the linear aero- What goes around comes around, though; the spike engine—will work. Though Soviet space pro -gram conceived in the 1970s as a space test flew a sub-scale craft shuttle motor, it was ruled out for very much like the X-24, that program in favor of conventional and NASA is evaluating a similar craft, built by rocket motors, considered less risky Scaled Composites, as at the time. an Inter-national Space Now, Lockheed believes, the tech- Station emergency crew nology for a practical aerospike return vehicle. engine is available; the company has flown the concept aboard an SR-71 test bed. The linear aerospike is described as an “inside out” rocket motor, with fuel combustion taking place outside of a central core. The concept planned to select a single contractor take over leadership in lift services. eliminates the weight of rocket bell from among the entries in the com- China and Russia also have captured a exhausts and much of the plumbing petition, it decided late last year to very significant chunk of the market. involved with today’s rockets, thus carry two companies into production: saving weight and cost, and should Boeing with its Delta IV variants and The Next Phase be more reliable than a standard Lockheed Martin with its Atlas and The Air Force was expected to an- rocket motor. Titan follow-ons. The companies nounce details of the next phase of About 15 test flights of the X-33 will compete on a per-launch basis. the EELV program this fall, includ- are planned from Edwards AFB, Cal- A test of medium-lift variants will ing how it will save money while if. Shorter-duration flights will end take place in Fiscal 2002, and the maintaining two unique launch ve- with a landing at Michael Army Air heavy-lift versions are set to fly in hicle production lines. The project is Field at the Army’s Dugway Prov- Fiscal 2003, with a full operational expected to carry the bulk of USAF ing Grounds in Utah, while longer capability by Fiscal 2005. Earlier satellites into the 2015–20 era, when flights will conclude at Malmstrom flights are definitely possible, given it is hoped that a thoroughly Reusable AFB, Mont. Most of the flight tests that both Boeing and Lockheed Launch Vehicle will be available. will average a week apart, but the Martin had planned to pursue their NASA has taken the lead on this program calls for demonstrating a respective vehicles with or without longer-term solution. While the space turnaround time of two days at least a “win” in the EELV competitions shuttle orbiter and its large external once. The suborbital flight to Utah and given that the demand for launch solid boosters can be used again after will take about 15 minutes while services is starting to overtake the extensive refurbishment, its huge the trip to Malmstrom will take 24 number of rockets available. external liquid fuel tank is discarded minutes. The program would, not coinci- on every flight, and turnaround time The Air Force is interested in both dentally, help US companies reclaim has never bested two months. NASA VentureStar and the X-33 as possible their dominance of the satellite and the Air Force want a system which launch vehicles for its own more launch business. American firms, consumes nothing but fuel and parts routine operations in space but will which once seemed unbeatable in and with a re-fly window measured not commit to the system for some commercial space, now have only 36 in days, not weeks. time, waiting to see that the concept percent of the annual launch market of The anticipated system for the RLV delivers on its promises. The X-33 around $2.8 billion. The Challenger is the Lockheed Martin VentureStar. does have a small payload bay, mea- accident in 1986, which forced a This lifting-body design is expected suring 5 feet by 10 feet. two-year shutdown in shuttle opera- to loft 50,000 pounds to Low Earth tions and left the US scrambling for Orbit—compared to the shuttle’s Spaceplane No More expendable alternatives, allowed the 51,000-pound maximum—at only “We envision a Space Operations European Arianespace consortium to about $1,000 a pound in the middle Vehicle system,” according to Air 42 AIR FORCE Magazine / November 1998 Force Space Command requirements Its key capabilities will be “launch, sive platform. The SMV could rou- chief Brig. Gen. Brian A. Arnold. return, and reuse on demand,” Ar- tinely “replenish the constellation,” The term “system” denotes that nold said.