A precursor composition comprising, before curing, ethylene propylene diene monomer (EPDM), silica, magnesium hydroxide, polymerized 1,2-dihydro-2,2,4-trimethylquinoline, a solid chlorinated paraffin, stearic acid, a five carbon petroleum hydrocarbon, trimethylolpropane trimethacrylate, and a peroxide. A rocket motor including a reaction product of the precursor composition and a method of insulating a rocket motor.

A precursor composition comprising, before curing, ethylene propylene diene monomer (EPDM), zinc oxide, silica, polymerized 1,2-dihydro-2,2,4-trimethylquinoline, a solid chlorinated paraffin, stearic acid, a five carbon petroleum hydrocarbon, trimethylolpropane trimethacrylate, and a peroxide. A rocket motor including a reaction product of the precursor composition and a method of insulating a rocket motor.

Hanger assemblies for coupling heat shield liners to cases of gas turbine engines are disclosed. The disclosed hanger assemblies include a pivoting joint coupled between a first segment and a second segment. The first segment is coupled to the liner by a liner attachment assembly and the second segment is coupled to the case by a case attachment assembly. At least one of the liner attachment assembly or the case attachment assembly permits translational movement of the first or second segments respectively with respect to the liner or case to accommodate for thermal expansion in the axial direction.

Apparatus, methods and computer programs are provided. In one example, an apparatus is a rocket motor, comprising: a casing having a length dimension, a width dimension and a depth dimension, wherein the length dimension is greater than the width dimension and greater than the depth dimension; and propellant, located inside the casing, arranged to generate a force in a direction that is substantially perpendicular to the length dimension of the casing.

A solid rocket motor includes a propellant grain and a barrier shielding at least a portion of the grain. The barrier is impermeable to water, oxygen, nitrogen, and volatile solid propellant species.

The present disclosure relates to propellant grain configuration in solid rocket motors. In one embodiment, the propellant grain is a case-bonded, forward-swept, deep finocyl grain offering significant flexibility in tailoring burn surface area regression profiles to meet different performance requirements even while allowing for high propellant volumetric loading densities. The grain comprises of two or more longitudinal fin cavities with forward swept leading edges, circular-patterned about an axial cavity.

A multi-component structure includes a first hybrid metal composite structure, a second hybrid metal composite structure, and a joint structure. The first and second hybrid metal composite structures include layers, each layer comprising a fiber composite material structure including a fiber material dispersed within a matrix material and at least one metal ply located between layers of the layers. The joint structure extends between and connects the first hybrid metal composite structure and the second hybrid metal composite structure. Additionally, the joint structure exerts a clamping force on the first and second hybrid metal composite structures and to reduce gaps between the layers, between the layers and the at least one metal ply, and between the joint structure and the first and second hybrid metal composite structures to less than half a thickness of the at least one metal ply.

Solid rocket motors or ramjets may be provided. Such devices may include a combustion chamber containing at least one fuel, a metal phase alloy film within the combustion chamber, where the metal phase alloy film coupled to the at least one fuel, and an activator operably coupled to the metal phase alloy film, the activator including an electrical activation system, a laser activation system, or an initiator activation system. This allows combined functional features on pulse motors to release inhibitors and ignite solid fuel/propellant. Fast reactions can be achieved by controlling the thickness of the alloys and using multiple layers to achieve the areal energy density. Foils can be rolled and inserted into the fuel/propellant bore. When rolled, it can easily follow the grain bore diameter changes with temperature and provide no additional mechanical loads to the grain.

A propellant load includes a propellant block, containing energetic charges in a crosslinked binder, arranged in a structure having a thermal protection; the crosslinked binder being an energetic binder including a polymer, more polar than hydroxytelechelic polybutadiene (HTPB), which is crosslinked and an energetic plasticizer, the polymer non-crosslinked representing less than 14% of the volume of the propellant block; a bonding layer, based on crosslinked hydroxytelechelic polybutadiene (HTPB), between the thermal protection and the propellant block; and a system for mechanical reinforcement of the bonding layer/propellant block bond, present on at least part of the bonding layer/propellant block interface, including grains embedded in part in the bonding layer and the complementary part thereof being embedded in the propellant block: made of a pyrotechnically inert material, and that has a surface energy greater than 34 mJ/m.sup.2; and the largest dimension of which is between 0.3 and 5.2 mm.

A vacuum insulated blast tube includes an insulating layer of a burn resistant material such as phenolic resin formed on an interior surface of the blast tube to provide the necessary erosion and thermal insulation properties to protect the blast tube and a vacuum insulated layer formed in the walls of the blast tube itself to provide the additional thermal insulation properties to protect any non-propulsive sub-systems positioned in the void space around the blast tube. A void space in the walls of the blast tube is held under vacuum with a pressure of less than 25 Torr and a thermal conductivity Tcond_vac of less than one-third of the thermal conductivity of air Tcond_air to form the vacuum insulation layer.