21st Century Spaceplanes and Space Expeditionary Forces: Pivotal Capability for a Third Offset Strategy A White Paper February 2017 Executive Summary. Reusable spaceplanes offer a third offset strategy to the U.S. that builds on the first and second offsets of nuclear weapons followed by precision navigation, munitions and stealth. Military space systems today are satellites that are large, expensive, and typically take many years to develop, launch and employ. They are also very effective at their intended function; however, that effectiveness is also destabilizing in that it is motivating foreign nations to develop and potentially employ anti-satellite (ASAT) systems that would deny the U.S. the advantage of its space systems. Today, the U.S. is heavily dependent on space capabilities, as is the U.S. public, even as foreign threats to U.S. space systems have grown precipitously. Reusable spaceplanes are stabilizing in that they can responsively and routinely replenish satellites to any orbit, while also enabling rapid access to any part of the world – capabilities seminal to the Air Force vision of Global Vigilance…Global Reach…Global Power. Spaceplane attributes like launch on demand, routine space access and low flight costs enable many options for global reach, whether via “aircraft-like” sorties of spaceplanes with sensor suites or by launching satellites into constellations. Sorties with fully reusable spaceplanes enable overflight in a manner akin to past SR-71 flights, except they enable global reach at four nautical miles (nm) per second while accessing any point on earth, and most geographic locations in less than an hour. Moreover, spaceplanes are generally invulnerable to anti-ballistic missile, ASAT, and other anti-access and area-denial (A2/AD) systems. Spaceplanes, even those employing an expendable upper stage, can rapidly replace space assets, faster and cheaper than a near-peer can realistically destroy them. With aircraft-like sortie rates, spaceplanes can rapidly reconstitute our space asset losses and deliver new and tailored capabilities to theater commanders. An intriguing option for spaceplanes is the ability to launch recoverable and reusable satellites on demand, within hours or days of a crisis, and recover them after the crisis is over for refurbishment, upgrade, and reuse. 1 This white paper describes how spaceplanes can provide commanders with battle management command, control, communications, computers and intelligence (BMC4I) gathering capabilities. This third offset harkens back to the thoughts of early advocates of air power, except spaceplanes take airpower and power projection one-step further by offering flexible and rapid global reach not limited by the range and speed of conventional aircraft. Spaceplanes can potentially fly with impunity from the continental U.S., create effects globally without refueling or even the need to suppress air defenses, and render massive foreign military investments obsolete. Emerging spaceplane entrepreneurs. Today’s military space systems are large and expensive to both develop, launch and operate. It typically takes many years to develop and deploy new systems, which then must survive autonomously on orbit for years, often decades, further driving cost as well as spacecraft obsolescence. The emergence of partially and eventually fully reusable “spaceplanes” in the commercial and military sectors offers many new opportunities for more effective and efficient air and space operations. A key driver is space entrepreneurs who are rapidly changing the way the U.S. will access and employ space systems including billionaire’s Elon Musk at SpaceX, Jeff Bezos at Blue Origin, Paul Allen at Vulcan Aerospace, and large corporations backing DARPA’s Experimental Spaceplane One – XS-1. As illustrated in Figure 1, the coming spaceplanes don’t always look like traditional aircraft; however, they will earn the name with “aircraft-like” attributes including on-demand flight, high tempo operability, maintainability, reusability, reliability, rapid turn-around and low recurring flight costs. This paper will offer several concepts for employing spaceplanes to support military missions; however, the focus will be on Global Reach…Global ISR capabilities. Separate papers will address future options, which could enable new missions including conventional prompt global strike and space-based missile and space defenses. 2 Figure 1 – Today’s spaceplane’s offer the promise of “aircraft-like” operability Reusable space access. The emergence of reusable spaceplanes opens new approaches for executing traditional air and space missions, as well as enabling fundamentally new capabilities. Mature flight systems will enable both global reach sortie aircraft as well as rapid launch of payloads to orbit. The speed of orbital flight at over 4 nm/sec enables very rapid access to any location on earth. Figure 2 highlights the speed at which a reusable spaceplane can overfly or access any part of the earth from the continental United States. Most locations are accessible within an hour although some may take longer depending on the direction of flight and the distance (due west retrograde flight has more severe thermal environments). Figure 2 – Spaceplane global reach times from Holloman AFB 3 Today’s aircraft are most useful when complemented by a suite of weapon systems whether a target tracking and surveillance pod or a precision guided munition. Spaceplanes also require complementary assets: a small expendable stage for inserting payloads to their final orbit, a common aero vehicle for reentry and delivery of payloads to terrestrial locations, and a recoverable and reusable upper stage. For example, spaceplanes can use an expendable upper stage to launch conventional long life satellites, but they also incentivize a new class of spacecraft. Namely, satellites specifically designed for rapid launch and employment, followed by deorbit, reentry and land for refurbishment, upgrade, and reuse. As part of an overall operational concept for reusable spaceplanes, a Reusable Flyback (ReFLY) satellite was proposed in the 1990’s. ReFLY was a small, unmanned reusable upper stage, in essence a maneuverable and recoverable satellite bus or Space Maneuver Vehicle (SMV), enabling high ops tempo deployment and recovery of the satellite sensors/payload. The SMV has the potential capability to perform numerous satellite type missions where recovery of the payload is important. An early high cost, low ops tempo version of an SMV designed to launch on expendable launch vehicles (ELVs) was flight tested in the Air Force X-40 program and subsequently developed into the X-37 orbital test vehicle. However, ELVs are very expensive and they do not support high ops tempo flight for rapid emplacement of operational constellations. Today, as illustrated in Figure 3, several SMV concepts exist ranging from the use of capsules to the use of simple fabric heat shields. The key common feature is using these SMVs as components in reusable space architectures comprised of emerging commercial and/or military spaceplanes, and thereby taking advantage of low cost and high ops tempo launch. Figure 3 – Space Maneuver Vehicle’s enable on-orbit maneuver & recovery 4 Although it does perform missions like a satellite, the SMV’s strength is in its extreme maneuver, direct recovery to ground and reuse. This offers additional military flexibility to the warfighter supporting a variety of missions. Maneuverability in particular offers on-orbit ∆V for orbit changes, deorbit and survivability. It is very hard to kill systems flying at over four nm/sec and maneuvering. Two of the Figure 3 concepts also offer the potential for low unit costs, the capsule on the left and the upper stage/satellite on the right. The latter has a high temperature fabric surrounding the upper stage/satellite that deploys like an inverted umbrella for reentry resulting in low heating, a slow terminal velocity and a simple vertical landing. Combined with the reusable space access systems identified earlier, an SMV provides another flexible option for supporting rapid deployment of tailored space forces, including a space expeditionary force. Their on-orbit maneuverability makes them less susceptible to anti-satellite threats, while their ability to recover, upgrade, refuel and refly promises both more effective and efficient military capabilities tailored to warfighter needs. Perhaps more to the point, rapid and routine replenishment of space capabilities, will likely deter foreign nations from employing ASATs in the first place. This is likely true whether employing traditional satellites, SMVs or the spaceplanes themselves to deliver that capability. High-tempo spaceplane operations. The operability characteristics of commercial and military spaceplanes promise a boon to the prospects for space-based systems. Spaceplanes can deploy satellites reliably, quickly and on-demand. Space assets often take decades to develop, test and employ, and once launched their operating life is limited. Spaceplanes can break this cost equation via on-demand and routine space access. The ability of aircraft to “fly- fix-fly” enables easy and rapid upgrades, especially when compared to space systems which often taken decades and many billions of dollars to field. A good example is Synthetic Aperture Radar (SAR) systems that flew routinely on the SR-71 two decades before SAR ever flew in space. Spaceplanes and reusable satellites can provide similar on-orbit test and rapid recovery