Space shuttle rockets

There now exist alternatives or sufficient quantities of controlled substances for almost all applications of ozone-depleting solvents. Exceptions have been noted for certain laboratory and analytical uses and for manufacture of space shuttle rocket motors. HCFCs have not been adopted on a large scale as alternatives to CFC solvents. In the near term, however, they may be needed as the conventional substances in some limited and unique applications. HCFC-141b is not a good replacement for methyl chloroform (1,1,1 -trichloroethane) because its ODP is three times higher. Alternatives for specific uses of ozone-depleting solvents are briefly described below. 

It is interesting to note that flie Space Shuttle rocket motor incorporates a cold oscillation damper, called a POGO suppressor, in the LOX pumping Une between low pressure and high pressure turbo-pumps [16,17]. 

Originally developed for tyre cords, Kevlar-type materials have also become widely used in composites. Uses include filament-wound rocket motors and pressure vessels, metal-lined Kevlar-overwrapped vessels in the space shuttle, boat and kayak hulls, Kevlar-epoxy helmets for the US military, and as one of the reinforcements in composite lorry cabs. 

May 4, 1988, explosions leveled a Pacific Engineering Production Co. (PEPCO) plant, at Henderson, NV, one of only two U.S. plants producing 20 million lb/ year (maximum of 40 million Ib/year - see Table 7.1-2) ammonium perchlorate for solid rocket fuel. It was the principal supplier for the space shuttle and sole supplier for the Titan rocket and several military missiles. 

Historically, polymer-matrix composite materials such as boron-epoxy and graphite-epoxy first found favor in applications, followed by metal-matrix materials such as boron-aluminum. Ceramic-matrix and carbon-matrix materials are still under development at this writing, but carbon-matrix materials have been applied in the relatively limited areas of reentry vehicle nosetips, rocket nozzles, and the Space Shuttle since the early 1970s. 

A final, somewhat variable outlet for large-scale liquid oxygen is as oxidant in rocket fuels for space exploration, satellite launching and space shuttles. For example, in the Apollo mission to the moon (1979), each Saturn 5 launch rocket used 1270 m (i.e. 1.25 million litres or 1450 tonnes) of liquid oxygen in Stage 1, where it oxidized the kerosene fuel (195 000 1, or about 550 tonnes) in the almost unbelievably short time of 2.5 min. Stages 2 and 3 had 315 and 76.3 m of liquid O2 respectively, and the fuel was liquid FI2. 

Modern composite solid propellant is a mechanical mixture of the powder-like chemicals and a binding resin. The propellant used for the Space Shuttle solid rocket boosters (SRBs) is a typical example of such mixture ... 

The Space Shuttle uses aluminum metal and ammonium perchlorate in its reusable booster rockets. The products of die reaction are aluminum oxide, aluminum chloride, nitrogen oxide gas, and steam. The reaction mixture contains 7.00 g of aluminum and 9.32 g of ammonium perchlorate. 

FIGURE 6.27 In this preparation of rocket fuel for the space shuttle, powdered aluminum is mixed with an oxidizing agent in a liquid polymer base that hardens inside the booster rocket shell. 

One spectacular example of the oxidizing ability of perchlorates is their use in the booster rockets of space shuttles. The solid propellant consists of aluminum powder (the fuel), ammonium perchlorate (the oxidizing agent as well as a fuel), and iron(III) oxide (the catalyst). These reactants are mixed into a liquid polymer, which sets to a solid inside the rocket shell. A variety of products can form when the mixture is ignited. One of the reactions is... 

Fossil fuels are nonrenewable, and combustion products contaminate the atmosphere. Consequently, scientists are searching for new sources of energy. One possibility is molecular hydrogen, which releases energy when it reacts with oxygen 2 H2(g) + 02(g) 2H2 0(/) + Energy Hydrogen powers the rockets of the space shuttle,... 

Richard Feynman loved to play the bongos. He also loved solving problems. He figured out the reason for the space shuttle Challenger s 1986 explosion by showing that cold weather caused the rubber seals of the booster rocket to fail. Feynman was one of the twentieth century s great theoretical physicists, a Nobel Prize winner who spent much of his career studying atoms. He knew as much about atoms as anyone in the world, and this is what he said about them in his book Six Easy Pieces ... 

The thunderous roar of a rocket s engines and the tremendous white clouds of smoke that accompany lift-off—these sensations evoke powerful emotions in any one viewing a Space Shuttle launch. The chemistry of the propellant mixture is responsible for the billowy clouds as the Shuttle soars into the sky. 

The solid rocket boosters of the Space Shuttle are appropriately named for the solid propellant loaded within them. The ignition provided by the reaction of the solid aluminum powder and ammonium perchlorate powder generates a finely divided white powder known as alumina, various gases, and an extensive amount of heat. The dispersal of the white powder in the gases streaming from the boosters creates the billowy white appearance. 

The propellant mixture in each solid rocket booster of the Space Shuttle contains ammonium perchlorate ( the oxidizer, 69.6% by weight), aluminum ( the fuel, 16% by weight), an iron oxide catalyst (0.4% by weight), a polymeric binder that... 

Solid Rocket Boosters. NASA Space Shuttle Reference Manual,... 

The Space Shuttle Solid Rocket Boosters. Student Space Awareness — National Web Team, University of Arizona Chapter of Students for the Exploration and Development of Space, http //seds.lpl.arizona.edu/ssa/docs/Space.Shuttle/srb.shtml... 

Since liquid hydrogen has the greatest energy content per unit weight of any fuel, NASA used liquid hydrogen as the primary fuel for the Saturn 5 moon rockets and the Space Shuttle. 

A major problem for the SPS is the current cost of space launches. Current rates on the Space Shuttle are 3,000 to 5,000 per pound ( 6,600/ kg and 11,000/kg). Launch costs of less than 400-500/kg are thought to be necessary for SPS. Economies of scale on expendable vehicles could provide some large reductions in launch costs. Thousands of rocket launches could reduce the costs by ten to twenty times based on experience with similar technical achievements. This places the costs into the range where this system could be conceivably attempted. Large reusable vehicles could... 

The two rocket booster engines used in a space shuttle launch contain a solid mixture of aluminum and ammonium perchlorate. 

Similarly, transporting, storing at the station, and pumping liquid hydrogen at 21K is an even more formidable task. Everyone knows it well what kind of safety precautions are undertaken when a space shuttle lifting main rocket is fuelled with liquid hydrogen and oxygen. 

The U.S. Space Shuttle, for example, has two large solid-rocket boosters for its launch stage. The booster propellant has the following composition ... 

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