A nose cone is the

conical A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines conn ...

ly shaped forwardmost section of a

rocket A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entire ...

guided missile In military terminology, a missile is a guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor. Missiles are thus also called guided missiles or guided rockets (when a previously unguided rocket ...

aircraft An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. ...

, designed to modulate oncoming airflow behaviors and minimize aerodynamic drag. Nose cones are also designed for submerged

watercraft Any vehicle used in or on water as well as underwater, including boats, ships, hovercraft and submarines, is a watercraft, also known as a water vessel or waterborne vessel. A watercraft usually has a propulsive capability (whether by sail ...

such as submarines,

submersible A submersible is a small watercraft designed to operate underwater. The term "submersible" is often used to differentiate from other underwater vessels known as submarines, in that a submarine is a fully self-sufficient craft, capable of in ...

s and

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, s ...

es, and in high-speed

land vehicle A vehicle (from la, vehiculum) is a machine that transports people or cargo. Vehicles include wagons, bicycles, motor vehicles (motorcycles, cars, trucks, buses, mobility scooters for disabled people), railed vehicles (trains, trams), w ...

s such as

rocket car A rocket car is a land vehicle propelled by a rocket engine. A rocket dragster is a rocket car used for competing in drag racing, and this type holds the unofficial world record for the 1/4 mile. Fritz von Opel was instrumental in popularizin ...

s and velomobiles.

Rockets

On a suborbital rocket vehicle it consists of a chamber or chambers in which 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 In aerodynamics, a hypersonic speed is one that exceeds 5 times the speed of sound, often stated as starting at speeds of Mach 5 and above. The precise Mach number at which a craft can be said to be flying at hypersonic speed varies, since i ...

flight was done towards creating viable nose cone designs for the atmospheric reentry of spacecraft and ICBM reentry vehicles. In a satellite launch vehicle, the nose cone may become the satellite itself after separating from the final stage of the rocket, or it may be used as a

payload fairing A payload fairing is a nose cone used to protect a spacecraft payload against the impact of dynamic pressure and aerodynamic heating during launch through an atmosphere. An additional function on some flights is to maintain the cleanroom enviro ...

to shield the satellite until out of the atmosphere, then separating (often in two halves) from the satellite.

Aircraft

On airliners the nose cone is also a

radome A radome (a portmanteau of radar and dome) is a structural, weatherproof enclosure that protects a radar antenna. The radome is constructed of material transparent to radio waves. Radomes protect the antenna from weather and conceal antenn ...

protecting the

weather radar Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type (rain, snow, hail etc.). Modern weather radars are mostly puls ...

from aerodynamic forces. Air India B 777

The shape of the nose cone must be chosen for minimum drag so a

solid of revolution In geometry, a solid of revolution is a solid figure obtained by rotating a plane figure around some straight line (the '' axis of revolution'') that lies on the same plane. The surface created by this revolution and which bounds the solid is ...

is used that gives least resistance to motion. The article on nose cone design contains possible shapes and formulas.

Hypersonic

Due to the extreme temperatures involved, nose cones for high-speed applications (e.g. hypersonic speeds or atmospheric reentry of

orbit In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such a ...

al vehicles) have to be made of

refractory In materials science, a refractory material or refractory is a material that is resistant to decomposition by heat, pressure, or chemical attack, and retains strength and form at high temperatures. Refractories are polycrystalline, polyphase ...

materials.

Pyrolytic carbon Pyrolytic carbon is a material similar to graphite, but with some covalent bonding between its graphene sheets as a result of imperfections in its production. Pyrolytic carbon is man-made and is thought not to be found in nature.Ratner, Buddy D. ...

is one choice, reinforced carbon-carbon composite or

HRSI The Space Shuttle thermal protection system (TPS) is the barrier that protected the Space Shuttle Orbiter during the searing heat of atmospheric reentry. A secondary goal was to protect from the heat and cold of space while in orbit. Materia ...

ceramics are other popular choices. Another design strategy is using ablative heat shields, which get consumed during operation, disposing of excess heat that way. Materials used for ablative shields include, for example

carbon phenolic Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon mak ...

polydimethylsiloxane Polydimethylsiloxane (PDMS), also known as dimethylpolysiloxane or dimethicone, belongs to a group of polymeric organosilicon compounds that are commonly referred to as silicones. PDMS is the most widely used silicon-based organic polymer, as it ...

composite with

silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is o ...

filler and

carbon fiber Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers (Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon compo ...

s, or as in of some Chinese FSW reentry vehicles, oak

wood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of ligni ...

. In general, the constraints and goals for atmospheric reentry conflict with those for other high-speed flight applications; during reentry a high-drag blunt reentry shape is frequently used, which minimises the

heat transfer Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction ...

by creating a

shock wave In physics, a shock wave (also spelled shockwave), or shock, is a type of propagating disturbance that moves faster than the local speed of sound in the medium. Like an ordinary wave, a shock wave carries energy and can propagate through a me ...

that stands off from the vehicle, but some very-high-temperature materials may permit sharper-edged designs.

Nose cone design

Given the problem of the

aerodynamic Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dyn ...

design A design is a plan or specification for the construction of an object or system or for the implementation of an activity or process or the result of that plan or specification in the form of a prototype, product, or process. The verb ''to design'' ...

of the nose cone section of any vehicle or body meant to travel through a compressible fluid medium (such as a

missile In military terminology, a missile is a missile guidance, guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor. Missiles are thus also called guided missiles or guided rockets (when a previously ...

bullet A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. Bullets are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax. Bullets are made in various shapes and ...

), an important problem is the determination of the nose cone geometrical shape for optimum performance. For many applications, such a task requires the definition of a

shape that experiences minimal resistance to rapid motion through such a fluid medium, which consists of elastic particles.

References

{{reflist Rocketry Aircraft components

Rockets

Aircraft

Hypersonic

Nose cone design

See also

References