Fears about expanding war into space are ridiculous. Space is the ideal place for war -- no civilians, no cities, no environmental damage; there is nothing in space but space. Mankind should pray for war in space so that war on Earth can be banned. Unfortunately, few nations have the resources and skills to challenge the USA in space, so most rely on traditional methods of warfare down on the surface. The US military is spending billions of dollars to establish what it calls "Space Dominance" supposedly to protect Americans against Inter-Continental Ballistic Missiles (ICBM)s. However, the proposed National Missile Defense (NMD) system will not work, see Chapter 17, so there is skepticism about the US military's true plans.
British Labour Member of Parliament, Tony Benn, stated that NMD is just a ruse to deploy space-to-ground weaponry. The ability to fire lasers from space at targets on the surface would be the ultimate weapon, as we all know from "Star Trek." However, lasers require a large power source that cannot be provided by a few solar panels. The cost and complexity of placing conventional weapons in space is prohibitive. Placing nuclear weapons in orbit for instant use is possible, but the 1967 Outer Space Treaty bans putting weapons of mass destruction in space or on the moon or other celestial bodies.
The 1972 Anti-Ballistic Missile Treaty prohibits targeting another country's satellites. Nevertheless, the Pentagon is planning for this event. The US Air Force implies that blinding satellites with lasers (dazzlers) or radio frequency jamming is not targeting, so this is deemed permissible. The US Air Force's Space Warfare Center stages major war games to focus on space as a theater for combat operations. The scenario at the heart of one game was an effort by the Chinese in 2017 to knock out US telecommunications.
NMD is complex because the Earth is round so the interceptor must rely on guidance from distant systems. However, NMD interceptors are ideal for hitting satellites. The US Air Force states that physically destroying satellites is a bad idea because this produces hundreds of chunks of orbiting space junk that will damage its own satellites. Nevertheless, both the USA and China have successfully destroyed satellites with missiles in tests, but these were in very low orbit so the debris soon fell to Earth and burned up.
This may result in nations launching satellites for that purpose, which was once proposed for NMD as the "brilliant pebbles" idea. A satellite would have an explosive charge surrounded by thousands of ball bearings. If war breaks out, an encrypted message would cause it to explode, polluting space with thousands of ball bearings that circle the planet for years and destroy numerous satellites. This may result in a new version of the Cold War Mutually Assured Destruction (MAD) concept. If war occurs, a nation may blow their MAD satellites and pollute space with killer ball bearings that destroy everyone's satellites.
Locating a satellite in orbit is not complex and has become a hobby for many "satellite watchers." Satellites can be seen just after sunset and just before dawn when the spacecraft are still in sunlight but the viewer is in shadow. The International Space Station, which can be as bright as Jupiter or even Venus, is a popular target. There is a great deal of information on the Internet about each satellite and their orbit. The US government is concerned about the ease in which this information can be found, and is trying to implement restrictions.
Since satellites are easy to track and cannot maneuver, they are ducks in a shooting gallery. Basic SCUD missiles or cheap "sounding rockets" fitted with a modified air-to-air missile can destroy those in low orbit. Powerful lasers are another anti-satellite weapon since they can blind and damage sensors. The US Air Force is so concerned that some Generals have proclaimed the right to take preemptive action against anything that may threaten their satellites. Here is a short article about the vulnerabilities of satellites: Space Reconnaissance Vulnerability, which provides an excellent overview, although it is years old. The author states the best solution is to accept that satellites are easily downed, so the answer is redundancy and a quick launch method for replacements.
Space warfare has become an issue across the spectrum of conflict. Anyone with an Internet connection has access to recent satellite imagery at websites such as: Terraserver and Google Earth. Customers can even place orders for satellites to take specific pictures of specific locations. Cryptome boldly posts all types of confidential government documents and images. There is little action the US government can take against companies and websites outside the United States, other than bombing their ground facilities or shooting down their satellites.
American Anti-Satellite Weapons
The US Congress banned anti-satellite weapons testing for ten years in 1985 fearing that it may spark an arms race. After this ban expired, the US Army gained approval for testing from President Clinton in order to "develop countermeasures" in case American satellites are targeted. On October 21, 1997, the US military tested an anti-satellite laser called the Mid-Infrared Advanced Chemical Laser (MIACL). This TRW laser (below) has been around since the 1980s, a left over from Reagan's "Star Wars" research programs.
Test laser shots were fired at an unused US Air Force satellite 260 miles above Earth. The satellite was not destroyed, but the Army was more interested in testing the vulnerability of delicate satellite sensors. Huge ground-based lasers cannot burn up anything in space because most all of the laser beam is scattered as it passes through the Earth's atmosphere. Nevertheless, blinding a reconnaissance satellite effectively destroys it.
In the photograph at left, notice the small images painted on the laser housing. The US military has a tradition of painting images of aircraft that a system has shot down. Apparently, MIACL has already downed five aircraft drones and a missile, plus a star and a top hat? Huge lasers will be prime targets in a major war so they need to be mobile. MIACL is too large to move on trucks but a river barge could provide an ideal platform.
On the other hand, its probably more cost effective to use air-to-space missiles like the US Air Force ASAT. (right) This missile was successfully tested from an F-15 in 1985 when it destroyed a satellite in low orbit. In 2009, China upset the USA by shooting down one of its own dead satellites with a missile. The US military already fields several types of air-to-air missiles with a range in excess of 100 miles at sea level. If fired upward from 50,000 feet, they encounter little air resistance, so their range is more than doubled in anti-satellite role. However, their guidance fins fail, so they need tiny guidance rockets like those used in TOW missiles and NMD interceptor warheads.
Since satellites often stop functioning for unknown reasons, a mischievous nation can zap an expensive satellite with a laser and the owner could not know what caused it to fail. Countermeasures are difficult because laser light travels at the speed of light, so advance warning of an incoming beam is impossible. Countermeasures are possible, like a protective hatch that remains closed unless the satellite is in use. This is an important area that is mostly secret. In December 2000, UPI published an article revealing that the USA and the Soviet Union already fought in space. Read Space War. Other articles refuted those claims. Such issues are difficult to follow because whenever someone prints secretive information a counterintelligence team is quick to ask an expert friend to publish something to discredit the article.
Fundamentals of Space Launch
One of the problems military organizations face in developing military space systems is that most people who consider themselves knowledgeable about aerospace do not understand the fundamental challenges of space launch. Most assume the goal is to break out of the Earth's pull of gravity so the spacecraft can float in outer space. Most also assume that a spacecraft "flies" like an aircraft. These are false assumptions held by many military pilots and Generals. The fundamentals are not complex; here is a brief summary:
The basic objective for any spacecraft launched is to achieve a speed of 17,500 mph (~Mach 24). A speed of 25,000 mph is needed to escape the Earth's gravity and travel to the Moon, but 17,500 mph is sufficient for a spacecraft to shut off its engines and "make orbit"; i.e. continually circle the Earth like the Moon. Since 95% of the Earth's gravity remains even 100 miles from the surface, a spacecraft in orbit maintains balance between Earth's gravity and centrifugal force. While in orbit, the spacecraft is constantly falling back to Earth as the curve of the Earth moves away due to the Earth being round. To easily maintain orbit, a spacecraft needs to circle at least 100 miles from the Earth's surface to avoid tiny air particles at the very edge of the Earth's atmosphere. This causes "drag" and will "degrade" its orbit, causing it to "reenter" by falling back to Earth -- 100 miles is considered "low earth orbit." Spacecraft need more fuel to attain higher orbits, which are needed for varied reasons.
As a result, the challenge is not "getting up into Space" 100 miles high. A $100,000 SCUD missile actually goes into Space but runs out of fuel at Mach 3, so it's pulled back to Earth after a few minutes of "sub-orbital" flight and lands a few hundred miles away. Reaching Mach 24 requires a great deal of intense and sustained rocket power. Since there is little oxygen more than ten miles from the Earth's surface, air-breathing jet engines are of little value. Rockets must carry their own liquid oxygen (LOX) which is mixed with fuel to provide thrust, and must fly almost vertical to quickly escape the aerodynamic drag of Earth's atmosphere. As a result, spacecraft require ten times more propellant (i.e. LOX and fuel) per mission than aircraft. When you see a spacecraft ready for launch, more than 85% of its mass is fuel.
Mach 24 seems like an amazing speed since military fighter jet aircraft can only reach Mach 2. However, they must continually fight the resistance of the Earth's atmosphere, which also causes skin heating. When the world's fastest aircraft, the SR-71 spy plane, reached Mach 3 it actually glowed from the heat and expanded in size. The Earth's atmosphere is half as dense at 20,000 feet (3.8 miles). Large jet aircraft have a ceiling of around 45,000 feet (or 8.5 miles) because the air becomes so thin their wings cannot support their weight and their jet engines become starved of oxygen.
The best route for spacecraft is to quickly push almost vertically through the resistance of the Earth's dense atmosphere in order to accelerate past Mach 2 and take the shortest path to orbit. Launching spacecraft slightly eastward is best to take advantage of the rotation of the Earth, requiring around 5% less overall thrust. Launching near the equator also helps. For example, a spacecraft launched from Idaho requires 8% more fuel to make orbit than one from Ecuador. This explains why Florida was chosen for the Kennedy Space Center and Space X chose the southern tip of Texas for hits new launch facility. They are closer to the equator where spacecraft can launch eastward over an unpopulated ocean.
The Earth's atmosphere also causes problems with reentry. A spacecraft can pull out of orbit with a minor burst of thrust to slow it down. The Earth's gravity takes hold and begins to pull it down at an increasing rate. The falling spacecraft will reach high speeds before it enters the Earth's dense lower atmosphere and will burn up from friction unless it has a heat shield or uses rockets to slow down. The Space Shuttle used both techniques. Heat shields are normally made from thick ceramic tiles, similar to floor tile. As a result, they are heavy and slow spacecraft during launch. Using rocket engines to slow down, like a retro-rocket, uses fuel, which is also heavy. This affects reusable boosters because anything that goes above 150,000 feet (28 miles) needs to carry extra weight in the form of heat tiles and fuel to slow decent back to Earth before wings or parachutes can be employed.
Limiting a spacecraft's deadweight (i.e. empty weight) is extremely important because mankind hasn't improved on the basic rocket engine's power-to-weight ratio for decades. It is amazing that man can place anything into space because only around 1-2% of a spacecraft's mass ends up in orbit; the remainder is burned up as fuel or dropped off in stages to shed deadweight so the payload can make orbit. This is why expendable boosters have been used for decades. They just fall back to Earth and burn up from friction since they have no heavy heat tiles for protection or parachutes or landing gear for recovery. This works, but makes space launch expensive.
NASA has always dreamed of a simple "single-stage to orbit" Reusable Launched Vehicle (RLV), where a spacecraft takes off and soars into orbit, and later glides home. The RLV would have to be massive to carry all the fuel needed to make orbit. However, adding heat tiles to a huge RLV, extra fuel for retro-rocket firings, and wings to land at an airfield, makes it far too heavy to launch into orbit. The best modern science has designed was the X-33 prototype that could have reached Mach 15 and returned home after an hour long "sub-orbital" flight. NASA reluctantly agreed the effort was pointless and it was canceled in January 2001.
Most space experts are surprised to learn that the Space Shuttle burned 40% of its fuel just to reach 1000 mph (Mach 1.3), as it struggled to push through the dense lower atmosphere with a full fuel load. After reaching Mach 1.3, air resistance was minimal and half its fuel mass gone, so it zoomed to Mach 24 and into orbit. Therefore, until some magical new technology arrives, the solution to cheaper space launch is to give spacecraft an assist "extra boost" during liftoff. For an example of the value of ground-based assisted launch, read about the Lockheed-Martin Atlas V, which was first launched on August 21, 2002 (below) as described by Aviation Week and Space Technology:
"At liftoff, the Atlas V weighed 737,547 lb.--125 tons heavier than the Atlas III. With only a 1.2 thrust-to-weight ratio, the heavy vehicle climbed slowly taking an agonizing 11 sec. to clear its umbilical tower. Once momentum had been established 4 sec. into the flight, the engine was throttled down slightly to 99%. At 17 sec. and 800 ft. altitude the RD-180 was gimbaled to begin the vehicle's pitch and roll program. At 100 sec. just after passing the critical Max-Q point, the engine was throttled down again to 95%. As propellant was depleted and the rate of acceleration increased, thrust was then modulated to hold a maximum of 5gs for Hot Bird payload structural limits."
So the Atlas V burns at full thrust for 10 seconds just to get 200 feet off the ground and up to 53.6 mph; using the formula v=sqr[2as]. At 20 seconds, it is 1000 feet high and traveling just 77.3 mph. The Atlas V first stage booster carries 627,000 lbs of propellant and burns for 236 seconds, which means it consumes 2657 lbs of propellant a second. Therefore, it consumes 53,000 lbs of propellant during the first 20 seconds just to reach 77 mph! Obviously, "blasting off" requires a tremendous amount of propellant. A Boeing 777 passenger aircraft can fly halfway around the globe with that much fuel.
The maximum payload for the basic Atlas V "501" is 9000 lbs to GTO; a high orbit. Therefore, a 77 mph ground-based assist for a modified Atlas V can put 53,000 lbs more mass into space. This doesn't mean that all the fuel savings result in greater payload into orbit since the second stage now has more payload to propel. Nevertheless, this small boost will result in 3000-8000 lbs more payload into orbit depending on final altitude and velocity.
Pneumatic launch is promising. The MX "Peacekeeper" ICBM used a steam pneumatic assisted launch system to propel the rocket out of its silo some 200 feet into the air before the first stage ignited. (below) This cold launch method increased the payload capability by approximately 10% and allowed the rocket silo to be reused. This method is now employed by a private company that uses surplus MX rockets for commercial launches. Hopefully, they will realize that a bigger boost and longer tube allows even more payload.
Aircraft Assisted Launch?
Since a ground-assisted boost is so valuable, why not use large aircraft to fly spacecraft much higher prior to launch? The main problem is size. The largest American aircraft is the US Air Force C-5B with a maximum payload of 270,000 lbs, compared the launch weight of the Atlas V of between 735,000 - 2,120,000 lbs, depending on the configuration. Therefore, a new aircraft at least three times larger than a C-5B is needed to launch a sizable rocket. Small rockets like Pegasus are air-launched from commercial aircraft, but the actual boost is tiny since the launch altitude is limited to 20,000-30,000 feet for large, fully-loaded aircraft because their wings begin to lose lift and jet engines become starved for oxygen. A massive rocket-powered spaceplane would not have this disadvantage, but would be costly to build and maintain, just like the Space Shuttle system.
Since numerous 20,000+ foot mountains exist around the world, it is easier to haul large spacecraft up high and launch where the air is half as dense as sea level. This is helpful, but the key element of assisted launch is upward velocity, which a mountaintop launch and even aircraft launch cannot provide because most velocity gained from horizontal launch is lost in doing work against air in changing the velocity vector to near vertical. An aircraft can perform a dive and pitch up maneuver for launch, but must be even larger and heavier to withstand the extreme stress on its airframe. The US Air Force is currently funding a plan to shove a small rocket out the back of a C-17 and firing it from 28,000 feet as it falls, however its payload is very limited from this negative assist.
Shooting a spacecraft upward off a rocket-powered sled is a better alternative. A rail system has no constraints on size and weight. An RLV shot up a 45 degree Sky Ramp and off 13,000 foot peak at Mach 2 will propel the RLV mass up to 54,000 feet, even before the RLV fires its engines; using the formula v^2=2as where v=vosin45 and vo~700m/s. and a~9.8m/s^2 we get s=12.5km~8miles + the 13000 feet starting point. So rocket sled ramp launch is like air launch, it just flings the RLV twice as high as any fully loaded transport can fly. It is also much safer and much cheaper than building and maintaining a massive aircraft or rocket-powered spaceplane.
Any workable method of ground-based assisted launch will be a breakthrough in spaceflight. NASA recognized this recently when it studied maglev assisted launch. It learned that current maglev technology remains grossly underpowered for space launch, but failed to note that simple rocket sleds can provide far greater assist. Most space "experts" dismiss the value of a Mach 1-2 launch assist because they assume this just saves 4-8% of the propellant needed to reach Mach 24. They fail to recognize the massive energy required to push a fully loaded spacecraft through the dense lower atmosphere and are surprised to learn the Space Shuttle burned 40% of its fuel to reach Mach 1.3. Until mankind develops a new propulsion method, ground-based launch assist is the only promising method for advancing spaceflight.
No one has developed a better method of putting objects into space since multi-stage expendable rockets were developed over 45 years ago. A reusable spacecraft has always been the goal, but the extra deadweight this adds makes the idea impractical, unless assisted launch is used. Pneumatic Assisted Launch and Rocket Sled Assisted Launch have emerged as superior methods to any launch proposal and do not require research or demonstrators since they've already been proven. However, new ideas face resistance from the "not invented here" attitude of large corporations and government institutions. If this technique is ignored in the United States, it will eventually appear in China, Russia, or India and eliminate America's dominance in Space.
The Commercial Space Race
The US military considers control of outer space vital to future warfare. Spaceprojects.com noted that the USA slipped to just 29% of the world’s launch market share in the year 2000, even though it had 48% of it in 1996, and apparently all of it the decade before. How did this happen if NASA has a larger space budget than all other civilian space agencies combined, as well as its congressional mandate to: "seek and encourage, to the maximum extent possible, the fullest commercial use of space"? How did some countries evolve from non-players in space two decades ago into dominant commercial players today? Most Americans are unaware that China routinely puts men into orbit.
Much of the blame falls upon the "Space Station", which eats up NASA's budget and accomplishes nothing. The Apollo program ended when America realized that expensive adventures to collect moon rocks were pointless. Imagine the panic at NASA after cancellation of support for the Space Station shatters their comfortable academic climate and everyone realizes that a superior method must be developed lest Congress deems them inept and cuts funding.
Innovative ideas like maglev launch, nuclear engines, anti-matter, and the space elevator require major funding. Some top physicists now agree that anti-gravity devices like the 512kV rotator can reduce the effects of gravity by spinning electrons, but they can't secure funding for research. Plans for pneumatic assisted launch have been around for years, but never funded. A large rail launch demonstrator requires a billion dollars. NASA canceled the promising VASIMR plasma engine research project citing a lack of funds. Unfortunately, little technological progress is expected unless NASA management is diverted from the continual burden of getting yet another expendable rocket system safely off the ground.
The US Air Force has become so frustrated by NASA's lethargy that it wants to build its own manned spacecraft. Until a major technological breakthrough allows a new form of space launch, all we have today is chemical rocket power that can provide just 1-2% payload by weight compared to their overall size. A massive rocket-powered horizontal launched spaceplane may work, but it would cost billions to build, must be several times larger than a 747, and may cost so much to launch and maintain that it erases the savings of being reusable, just like the Shuttle. If you add wings, landing gear, extra fuel and control engines to bring any spacecraft or fly-back booster back to Earth for reuse, that extra weight eliminates the payload.
This is something the new SpaceX corporation will rediscover. You can't just make a bigger spacecraft because that requires bigger wings, landing gear and engines. The only way an RLV can work is with a ground assist launch to Mach 1-2 up a mountainside or up through a tunnel. A nation that develops this inexpensive method of space launch can dominate any war in space.