A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants (fuel/oxidizer). The earliest rockets were solid-fuel rockets powered by gunpowder; The inception of gunpowder rockets in warfare can be credited to ancient Chinese ingenuity, and in the 13th century, the Mongols played a pivotal role in facilitating their westward adoption.
A hybrid-propellant rocket is a rocket with a rocket motor that uses rocket propellants in two different phases: one solid and the other either gas or liquid. The hybrid rocket concept can be traced back to the early 1930s.
Polyurethane refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced from a wide range of starting materials. This chemical variety produces polyurethanes with different chemical structures leading to many different applications. These include rigid and flexible foams, and coatings, adhesives, electrical potting compounds, and fibers such as spandex and polyurethane laminate (PUL). Foams are the largest application accounting for 67% of all polyurethane produced in 2016.
Ammonium perchlorate ("AP") is an inorganic compound with the formula NH4ClO4. It is a colorless or white solid that is soluble in water. It is a powerful oxidizer. Combined with a fuel, it can be used as a rocket propellant called ammonium perchlorate composite propellant. Its instability has involved it in a number of accidents, such as the PEPCON disaster.
A propellant is a mass that is expelled or expanded in such a way as to create a thrust or another motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the engine that expels the propellant is called a reaction engine. Although technically a propellant is the reaction mass used to create thrust, the term "propellant" is often used to describe a substance which contains both the reaction mass and the fuel that holds the energy used to accelerate the reaction mass. For example, the term "propellant" is often used in chemical rocket design to describe a combined fuel/propellant, although the propellants should not be confused with the fuel that is used by an engine to produce the energy that expels the propellant. Even though the byproducts of substances used as fuel are also often used as a reaction mass to create the thrust, such as with a chemical rocket engine, propellant and fuel are two distinct concepts.
Polyurea is a type of elastomer that is derived from the reaction product of an isocyanate component and an amine component. The isocyanate can be aromatic or aliphatic in nature. It can be monomer, polymer, or any variant reaction of isocyanates, quasi-prepolymer or a prepolymer. The prepolymer, or quasi-prepolymer, can be made of an amine-terminated polymer resin, or a hydroxyl-terminated polymer resin.
Polybutadiene acrylonitrile (PBAN) copolymer, also noted as polybutadiene—acrylic acid—acrylonitrile terpolymer is a copolymer compound used most frequently as a rocket propellant fuel mixed with ammonium perchlorate oxidizer. It was the binder formulation widely used on the 1960s–1970s big boosters. It is also notably used in NASA's Space Launch System, likely reusing the design from its Space Shuttle counterpart.
Hydroxylammonium nitrate or hydroxylamine nitrate (HAN) is an inorganic compound with the chemical formula [NH3OH]+[NO3]−. It is a salt derived from hydroxylamine and nitric acid. In its pure form, it is a colourless hygroscopic solid. It has potential to be used as a rocket propellant either as a solution in monopropellants or bipropellants. Hydroxylammonium nitrate (HAN)-based propellants are a viable and effective solution for future green propellant-based missions, as it offers 50% higher performance for a given propellant tank compared to commercially used hydrazine.
Polybutadiene [butadiene rubber, BR] is a synthetic rubber. It offers high elasticity, high resistance to wear, good strength even without fillers, and excellent abrasion resistance when filled and vulcanized. "Polybutadiene" is a collective name for homopolymers formed from the polymerization of the monomer 1,3-butadiene. The IUPAC refers to polybutadiene as "poly(buta-1,3-diene)". Historically, an early generation of synthetic polybutadiene rubber produced in Germany by Bayer using sodium as a catalyst was known as "Buna rubber". Polybutadiene is typically crosslinked with sulphur, however, it has also been shown that it can be UV cured when bis-benzophenone additives are incorporated into the formulation.
Rocket candy, or R-Candy, is a type of rocket propellant for model rockets made with a form of sugar as a fuel, and containing an oxidizer. The propellant can be divided into three groups of components: the fuel, the oxidizer, and the (optional) additive(s). In the past, sucrose was most commonly used as fuel. Modern formulations most commonly use sorbitol for its ease of production. The most common oxidizer is potassium nitrate (KNO3). Potassium nitrate is most commonly found in tree stump remover. Additives can be many different substances, and either act as catalysts or enhance the aesthetics of the liftoff or flight. A traditional sugar propellant formulation is typically prepared in a 65:35 (13:7) oxidizer to fuel ratio.
A pyrotechnic composition is a substance or mixture of substances designed to produce an effect by heat, light, sound, gas/smoke or a combination of these, as a result of non-detonative self-sustaining exothermic chemical reactions. Pyrotechnic substances do not rely on oxygen from external sources to sustain the reaction.
Ammonium perchlorate composite propellant (APCP) is a solid-propellant rocket fuel. It differs from many traditional solid rocket propellants such as black powder or zinc-sulfur, not only in chemical composition and overall performance but also by being cast into shape, as opposed to powder pressing as with black powder. This provides manufacturing regularity and repeatability, which are necessary requirements for use in the aerospace industry.
A flare or decoy flare is an aerial infrared countermeasure used by an aircraft to counter an infrared homing ("heat-seeking") surface-to-air missile or air-to-air missile. Flares are commonly composed of a pyrotechnic composition based on magnesium or another hot-burning metal, with burning temperature equal to or hotter than engine exhaust. The aim is to make the infrared-guided missile seek out the heat signature from the flare rather than the aircraft's engines.
Dr. V. N. Krishnamurthy is the former Dy. Director of VSSC and Honorable Director of ISRO-UoP Interaction cell. He obtained his M.Sc. from Madras University and Ph.D. from Indian Institute of Science, Bangalore in 1967. He joined Vikram Sarabhai Space Centre, in February 1968 as chief of analytical facility. He became head of the Propellant Engineering Division in 1976, Group Director Propellants Group in 1986, and Deputy Director in 1989 before retiring in February 1997. After retiring, he became the Honorary Director of DRDO-ISRO-UoP Cells, which coordinates the activities undertaken for ISRO and DRDO at University of Pune. His tenure was over in August 2004 and after that he worked as an editor for two different encyclopaedias. Now he spends his time writing books and doing special guest lectures at universities and colleges in India.
RocketMotorTwo (RM2) is a family of hybrid rocket engines developed for the Scaled Composites SpaceShipTwo suborbital spaceplane.
Rocket propellant is the reaction mass of a rocket. This reaction mass is ejected at the highest achievable velocity from a rocket engine to produce thrust. The energy required can either come from the propellants themselves, as with a chemical rocket, or from an external source, as with ion engines.
Moisture-cure polyurethanes -- or polyurethane prepolymer -- are isocyanate-terminated prepolymers that are formulated to cure with ambient water. Cured PURs are segmented copolymer polyurethane-ureas exhibiting microphase-separated morphologies. One phase is derived from a typically flexible polyol that is generally referred to as the “soft phase”. Likewise the corresponding “hard phase” is born from the di- or polyisocyanates that through water reaction produce a highly crosslinked material with softening temperature well above room temperature.
Zefiro is a family of solid-fuel rocket motors developed by Avio and used on the European Space Agency Vega rocket. The name Zefiro derives from the acronym ZEro FIrst stage ROcket, conceived when this motor was intended to be used as first and second stages of San Marco program of the Italian Space Agency (ASI). After its intended use as booster was shelved the acronym was dropped and only the reference to the Greek god of the west wind Zephyrus remained.
P120 is a solid-fuel first-stage rocket motor developed by Avio and ArianeGroup through the joint venture Europropulsion on behalf of European Space Agency for use on Vega C and Ariane 6.
The Solid Rocket Motor Upgrade (SRMU) was a solid rocket motor that was used as a booster on the Titan IVB launch vehicle. Developed by Hercules, it was intended to be a high-performance, low-cost upgrade to the UA1207 boosters previously used on Titan IV. Wound from carbon-fibre-reinforced polymer and burning a hydroxyl-terminated polybutadiene-bound ammonium perchlorate composite propellant, it was an ambitious upgrade building on Hercules' experience developing a filament-wound case for the Space Shuttle SRB. Originally intended to fly in 1990, it instead first flew in 1997 due to a protracted development and lack of demand. The SRMU performed successfully on all of its flights.
