Nose cone
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The term nose cone is used to refer to the forwardmost section of a rocket, guided missile or aircraft. The cone is shaped to offer minimum aerodynamic resistance. Nose cones are also designed for travel in and under water and in high speed land vehicles.
On a rocket vehicle it consists of a chamber or chambers in which a satellite, instruments, animals, plants, or auxiliary equipment may be carried, and an outer surface built to withstand high temperatures generated by aerodynamic heating. Much of the fundamental research related to hypersonic flight was done towards creating viable nose cone designs for the atmospheric reentry of spacecraft and ICBM reentry vehicles.
In a satellite vehicle, the nose cone may become the satellite itself after separating from the final stage of the rocket or it may be used to shield the satellite until orbital speed is accomplished, then separating from the satellite.
The shape of the nose cone must be chosen for minimum drag so a solid of revolution is used that gives least resistance to motion. The article on nose cone design contains possible shapes and formulae.
Due to the extreme temperatures involved, nose cones for high-speed applications (eg. hypersonic speeds or atmospheric reentry vehicles) have to be made of refractory materials. Pyrolytic carbon is one choice, reinforced carbon-carbon composite or HRSI ceramics are other popular choices. Other design strategy is using ablative heat shields, which get consumed during operation, disposing of excess heat that way. Popular materials for ablative shields are eg. carbon phenolic, polydimethylsiloxane composite with silica filler and carbon fibers, or, like in case of some Chinese FSW reentry vehicles, oak wood.[1]
