WO1991011676A2 - Hypervelocity drag reduction - Google Patents

Hypervelocity drag reduction Download PDF

Info

Publication number
WO1991011676A2
WO1991011676A2 PCT/GB1991/000111 GB9100111W WO9111676A2 WO 1991011676 A2 WO1991011676 A2 WO 1991011676A2 GB 9100111 W GB9100111 W GB 9100111W WO 9111676 A2 WO9111676 A2 WO 9111676A2
Authority
WO
WIPO (PCT)
Prior art keywords
projectile
heating
further characterized
accomplished
air
Prior art date
Application number
PCT/GB1991/000111
Other languages
French (fr)
Other versions
WO1991011676A3 (en
Inventor
Colin Humphry Bruce Jack
Original Assignee
Colin Humphry Bruce Jack
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Colin Humphry Bruce Jack filed Critical Colin Humphry Bruce Jack
Publication of WO1991011676A2 publication Critical patent/WO1991011676A2/en
Publication of WO1991011676A3 publication Critical patent/WO1991011676A3/en

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42BEXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B10/00Means for influencing, e.g. improving, the aerodynamic properties of projectiles or missiles; Arrangements on projectiles or missiles for stabilising, steering, range-reducing, range-increasing or fall-retarding
    • F42B10/32Range-reducing or range-increasing arrangements; Fall-retarding means
    • F42B10/38Range-increasing arrangements
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42BEXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B10/00Means for influencing, e.g. improving, the aerodynamic properties of projectiles or missiles; Arrangements on projectiles or missiles for stabilising, steering, range-reducing, range-increasing or fall-retarding
    • F42B10/32Range-reducing or range-increasing arrangements; Fall-retarding means
    • F42B10/38Range-increasing arrangements
    • F42B10/40Range-increasing arrangements with combustion of a slow-burning charge, e.g. fumers, base-bleed projectiles

Definitions

  • HYPERVELOCITY DRAG REDUCTION DESCRIPTION This invention relates to a technique for diminishing the drag force, and also the frictional heating, to which high velocity projectiles travelling within the atmosphere are subject.
  • the concept is to heat the air in front of the projectile. As the absolute temperature of a gas is raised, its density decreases by a corresponding factor (for a given external pressure, at equilibrium) . For example if a column of air in front of the projectile is heated to 3,000 degrees Kelvin and allowed to expand freely, it will form a 'tunnel' with a density about one- tenth that of the surrounding air. The drag force on the projectile will decrease by a corresponding amount. The heating of the front surface of the projectile will also be reduced.
  • heating may be performed by equipment on the projectile itself, or on the ground, or on another vehicle (for example, a second 'trail- blazing' projectile which precedes it in the same course).
  • electromagnetic energy e.g. by microwave or laser radiation
  • chemical reaction e.g. by releasing a substance which combines with atmospheric oxygen
  • kinetic heating in which energy of motion (of the projectile itself, or material released from the projectile, or from another source) is dissipated.
  • the heating may be performed by equipment on the projectile itself, or on the ground, or on another vehicle (for example, a second 'trail- blazing' projectile which precedes it in the same course).
  • the technique is applicable to any vehicle which traverses a medium sufficiently dense to cause significant retardation and/or heating. It is especially relevant to vehicles which travel at hypersonic velocity within the lower part of the Earth's atmosphere. These include spacecraft launched directly from the Earth's surface at orbital or escape speed using linear accelerators.
  • EXAMPLE 1 A ten-kilogram projectile is fired vertically from a railgun at sea level at a speed of 12 km/sec. Attached to the nose is a forward-pointing hollow metal pipe. Liquid nitrogen is pumped along this (incidentally serving to cool the pipe against atmospheric heating) to emerge as a fine spray. The nitrogen mixes with a larger mass of atmospheric air to form a plasma at temperature 6,000 degrees Kelvin. This plasma expands to about 20 times its original volume. Thus a cylinder of air which was originally one-quarter the diameter of the projectile expands to fill a cylinder slightly wider than the projectile itself. The drag force on the projectile is decreased by a corresponding amount.
  • the oxygen contained in the air has dissociated, decreasing the mean molecular weight and so further reducing the density.
  • N.B. Nitrogen is chosen becuse of its high dissociation temperature. Other choices are of course possible, for example liquid argon. If water is used, it would dissociate, absorbing 23 MJ/kg energy. The high specific volume of the hydrogen generated would however tend to counterbalance this disadvantage at very high speeds.
  • EXAMPLE 2 A 20 tonne projectile is released from a horizontal linear accelerator at 9 km/sec at a shallow upwards angle (vertical speed 900 metres/sec) at a point 3,000 metres above sea level. The projectile is 2 metres in diameter with Cd 0.2. It is protected by releasing liquid nitrogen from a probe attached to the nose, to create a 6,000 degree Kelvin plasma tunnel, as in the previous example. Total speed loss will also be 2%: the longer atmospheric traverse is compensated by higher mass per frontal area. The nitrogen required will weigh 10% of total projectile weight, however, because its specific kinetic energy is only 40 MJ/kg at this lower speed.
  • EXAMPLE 3 A hypersonic aircraft releases liquid hydrogen from a probe attached to its nose. This combusts with the oxygen in the surrounding atmosphere to raise its temperature to 3,000 degrees Kelvin, lowering the drag on the aircraft body by a factor of 10.
  • a hypersonic projectile has a rigid spike of material attached to its nose. This heats the air which impacts it, ahead of the main projectile, creating a heated gas tunnel as in the previous examples.
  • EXAMPLE 5 One projectile/vehicle precedes another. It heats the air it passes through creating a heated gas tunnel for the benefit of the second vehicle (by direct friction, or by releasing an inert or combustible substance, etc.).
  • EXAMPLE 6 A ground installation fires a beam of electromagnetic energy (e.g. laser or microwave radiation) to heat the air ahead of a projectile.
  • the projectile might help to intercept or focus this energy. For example it might release a 'plasma dopant' to promote the formation of a plasma capable of absorbing the energy transmitted; or focus a microwave beam to a point forward of its nose by diffraction or other effects.
  • EXAMPLE 7 A ground installation fires a beam of electromagnetic energy (e.g. laser or microwave radiation) to create a tunnel of hot air through which a projectile/vehicle subsequently passes.
  • a beam of electromagnetic energy e.g. laser or microwave radiation
  • EXAMPLE 8 A projectile, or string of projectiles in succession, are fired to create a heated gas tunnel through which another projectile/ vehicle subsequently passes.
  • the projectiles might for example be fired by railgun, or descend from an orbital installation.
  • a fuze of solid propellant hangs vertically from a helicopter or balloon, or is fired ballistically from a line gun, or trailed behind an aircraft. It detonates, or burns from the end, to create a heated gas tunnel as previously described. The projectile may be launched when combustion is complete, or alternatively follow the fuze as it burns.
  • EXAMPLE 10 A projectile as in any previous example, but using a stream of gas or powder or pellets (as distinct from a liquid) to heat the air.
  • EXAMPLE 11 A column of air is heated by vibration (e.g. by focussed ultrasound) to provide the heated tunnel effect.
  • EXAMPLE 12 A rocket motor or jet engine on the ground fires its exhaust upwards (or a jet of heated steam or air from any source is used) to provide a column or mass of superheated air or other gas(es) through which a vehicle or projectile is subsequently passed.
  • EXAMPLE 13 A powder, vapour, liquid or gas is 'sowed' through a volume of the atmosphere. Its subsequent ignition provides a heated tunnel.
  • EXAMPLE 14 The passage of a projectile or vehicle through the atmosphere is assisted by a combination of the preceding methods.

Abstract

A projectile traversing the lower atmosphere at hypersonic speed suffers high aerodynamic drag. This may be reduced by preheating the air ahead of it to create a 'plasma tunnel', within which the temperature is raised to several times the ambient with a corresponding reduction in density, reducing the drag force. Typically, overall drag may be reduced by a factor of 10-100 in this way. The heating may be accomplished in several ways. For example the projectile may be equipped with a prove attached to the nose through which liquid is sprayed. The liquid is brought to rest by the surrounding air, converting its kinetic energy to heat. A particular application is to electromagnetic space launch systems. A projectile accelerated to orbital or escape velocity at ground level by linear accelerator can traverse the atmosphere with acceptable speed loss.

Description

HYPERVELOCITY DRAG REDUCTION DESCRIPTION This invention relates to a technique for diminishing the drag force, and also the frictional heating, to which high velocity projectiles travelling within the atmosphere are subject. The concept is to heat the air in front of the projectile. As the absolute temperature of a gas is raised, its density decreases by a corresponding factor (for a given external pressure, at equilibrium) . For example if a column of air in front of the projectile is heated to 3,000 degrees Kelvin and allowed to expand freely, it will form a 'tunnel' with a density about one- tenth that of the surrounding air. The drag force on the projectile will decrease by a corresponding amount. The heating of the front surface of the projectile will also be reduced. Many different methods of heating may be used. These include electromagnetic energy (e.g. by microwave or laser radiation), chemical reaction (e.g. by releasing a substance which combines with atmospheric oxygen) and kinetic heating, in which energy of motion (of the projectile itself, or material released from the projectile, or from another source) is dissipated. The heating may be performed by equipment on the projectile itself, or on the ground, or on another vehicle (for example, a second 'trail- blazing' projectile which precedes it in the same course). The technique is applicable to any vehicle which traverses a medium sufficiently dense to cause significant retardation and/or heating. It is especially relevant to vehicles which travel at hypersonic velocity within the lower part of the Earth's atmosphere. These include spacecraft launched directly from the Earth's surface at orbital or escape speed using linear accelerators.
Specific embodiments of the invention will now be described by way of example.
EXAMPLE 1 A ten-kilogram projectile is fired vertically from a railgun at sea level at a speed of 12 km/sec. Attached to the nose is a forward-pointing hollow metal pipe. Liquid nitrogen is pumped along this (incidentally serving to cool the pipe against atmospheric heating) to emerge as a fine spray. The nitrogen mixes with a larger mass of atmospheric air to form a plasma at temperature 6,000 degrees Kelvin. This plasma expands to about 20 times its original volume. Thus a cylinder of air which was originally one-quarter the diameter of the projectile expands to fill a cylinder slightly wider than the projectile itself. The drag force on the projectile is decreased by a corresponding amount.
If the projectile has frontal area 0.01 m2 and aerodynamic coefficient Cd = 0.2, without this protection it would lose half its speed to air resistance. With the protection speed loss is reduced to 2%.
Heating the air requires approximately 6 million J/kg. Dissociation of the oxygen in it consumes a further 0.5 million J/kg. (Almost no nitrogen dissociates at this temperature.) At 12 km/sec, each kilogram of mass carried in the projectile has 72 million Joules kinetic energy. Thus l kg of nitrogen from the projectile heats approximately 10 kg of air, and only one- twentieth of the air which originally occupied the space in front of the projectile is heated. So the on-board nitrogen"reservoir uses 0.5 kg during the whole atmospheric traverse = 5% of projectile weight. Additional benefits could include:
1. The air impacted by the nitrogen released is pushed forward, and so impacts the projectile nosecap at slightly reduced relative velocity, further diminishing the drag force.
2. The oxygen contained in the air has dissociated, decreasing the mean molecular weight and so further reducing the density.
3. Heating on the projectile surface is reduced. (This benefit may be traded by making the projectile more streamlined. An unprotected projectile would need an ablative nosecap and must be quite blunt. A protected projectile could be needle-nosed, with the heating absorbed into the metal skin, with Cd up to 10 times lower, further reducing drag loss.)
The weight of the nose probe must also be allowed for. Its optimum length relative to the projectile radius may be approximated by dividing the projectile speed by the speed of sound in the surrounding air: ratio 40 = 2.2 metres forward of the widest part of the projectile. Maximum pumping rate is approx 1 kg/sec giving internal diameter of a few millimetres. In practice the probe will widen towards the base, being integrated into the projectile nose shape. The nitrogen will be expelled from a pressure reservoir at the appropriate rate by a pressurizing gas.
N.B. Nitrogen is chosen becuse of its high dissociation temperature. Other choices are of course possible, for example liquid argon. If water is used, it would dissociate, absorbing 23 MJ/kg energy. The high specific volume of the hydrogen generated would however tend to counterbalance this disadvantage at very high speeds. EXAMPLE 2 A 20 tonne projectile is released from a horizontal linear accelerator at 9 km/sec at a shallow upwards angle (vertical speed 900 metres/sec) at a point 3,000 metres above sea level. The projectile is 2 metres in diameter with Cd 0.2. It is protected by releasing liquid nitrogen from a probe attached to the nose, to create a 6,000 degree Kelvin plasma tunnel, as in the previous example. Total speed loss will also be 2%: the longer atmospheric traverse is compensated by higher mass per frontal area. The nitrogen required will weigh 10% of total projectile weight, however, because its specific kinetic energy is only 40 MJ/kg at this lower speed.
EXAMPLE 3 A hypersonic aircraft releases liquid hydrogen from a probe attached to its nose. This combusts with the oxygen in the surrounding atmosphere to raise its temperature to 3,000 degrees Kelvin, lowering the drag on the aircraft body by a factor of 10.
EXAMPLE 4 A hypersonic projectile has a rigid spike of material attached to its nose. This heats the air which impacts it, ahead of the main projectile, creating a heated gas tunnel as in the previous examples.
EXAMPLE 5 One projectile/vehicle precedes another. It heats the air it passes through creating a heated gas tunnel for the benefit of the second vehicle (by direct friction, or by releasing an inert or combustible substance, etc.).
This concept exrtends to a 'train' of a larger number of projectiles, each assisting the passage of those following. EXAMPLE 6 A ground installation fires a beam of electromagnetic energy (e.g. laser or microwave radiation) to heat the air ahead of a projectile. The projectile might help to intercept or focus this energy. For example it might release a 'plasma dopant' to promote the formation of a plasma capable of absorbing the energy transmitted; or focus a microwave beam to a point forward of its nose by diffraction or other effects.
EXAMPLE 7 A ground installation fires a beam of electromagnetic energy (e.g. laser or microwave radiation) to create a tunnel of hot air through which a projectile/vehicle subsequently passes.
EXAMPLE 8 A projectile, or string of projectiles in succession, are fired to create a heated gas tunnel through which another projectile/ vehicle subsequently passes. The projectiles might for example be fired by railgun, or descend from an orbital installation.
EXAMPLE 9 A fuze of solid propellant hangs vertically from a helicopter or balloon, or is fired ballistically from a line gun, or trailed behind an aircraft. It detonates, or burns from the end, to create a heated gas tunnel as previously described. The projectile may be launched when combustion is complete, or alternatively follow the fuze as it burns.
EXAMPLE 10 A projectile as in any previous example, but using a stream of gas or powder or pellets (as distinct from a liquid) to heat the air. EXAMPLE 11 A column of air is heated by vibration (e.g. by focussed ultrasound) to provide the heated tunnel effect.
EXAMPLE 12 A rocket motor or jet engine on the ground fires its exhaust upwards (or a jet of heated steam or air from any source is used) to provide a column or mass of superheated air or other gas(es) through which a vehicle or projectile is subsequently passed.
EXAMPLE 13 A powder, vapour, liquid or gas is 'sowed' through a volume of the atmosphere. Its subsequent ignition provides a heated tunnel.
EXAMPLE 14 The passage of a projectile or vehicle through the atmosphere is assisted by a combination of the preceding methods.

Claims

1. A system for reducing the atmospheric drag on a projectile travelling through an atmosphere at high speed, characterized in that air ahead of the projectile is heated and consequently expands, reducing the density per unit volume of the gas impacted by the projectile.
2. A system for reducing the heating of the surface of a projectile travelling through an atmosphere at high speed, characterized in that air ahead of the projectile is heated and consequently expands, reducing the density per unit volume of the gas impacted by the projectile.
3. A system for reducing both the atmospheric drag on, and the heating of the surfce of, a projectile travelling through an atmosphere at high speed, characterized in that air ahead of the projectile is heated and consequently expands, reducing the density per unit volume of the gas impacted by the projectile.
4. A system as claimed in claim 3, further characterized in that the projectile is highly streamlined, so further reducing the atmospheric drag.
5. A system as claimed in claim 4, further characterized in that the projectile nosecone does not ablate.
6. A system as claimed in claim 5, further characterized in that the heating on the projectile nosecone is absorbed into the (metal) skin.
7. A system as claimed in claim 3, further characterized in that the heating of the air ahead of the projectile is accomplished wholly or partly by electromagnetic energy.
8. A system as claimed in claim 3, further characterized in that the heating of the air ahead of the projectile is accomplished wholly or partly by chemical combustion.
9. A system as claimed in claim 3, further characterized in that the heating of the air ahead of the projectile is accomplished wholly or partly by kinetic heating.
10. A system as claimed in claim 9, further, characterized in that the kinetic heating is accomplished by the projectile's own kinetic energy.
11. A system as claimed in claim 8 or claim 9, further characterized in that the heating is accomplished by material released from the projectile.
12. A system as claimed in claim 11, further characterized in that the material released emerges from a forward-pointing pipe attached to the projectile nose.
13. A system as claimed in claim 12, further characterized in that the material pumped along the pipe serves the additional purpose of cooling the pipe against atmospheric heating.
14. A system as claimed in claim 8 or claim 9, further characterized in that the heating is accomplished by means of a leading 'trail-blazing' projectile.
15. A system as claimed in claim 8 or claim 9, further characterized in that the heating is accomplished by means of material released from a leading 'trail-blazing' projectile.
16. A system as claimed in claim 8, further characterized in that the combustive heating is accomplished by releasing liquid hydrogen into the surrounding air.
17. A system as claimed in claim 9, further characterized in that the kinetic heating is accomplished by releasing liquid nitrogen into the surrounding air.
18. A system as claimed in claim 10, further characterized in that the kinetic heating is accomplished by air friction on a forward-pointing spike attached to the main nosecone of the projectile.
19. A system as claimed in claim 14, further characterized in that a train of trail-blazing projectiles, rather than a single one, is used.
20. A system as claimed in claim 3, further characterized in that the heating of the air ahead of the projectile is accomplished wholly or partly by atmospheric vibration (sound energy).
21. A system as claimed in claim 3, further characterized in that the heating of the air ahead of the projectile is accomplished wholly or partly by a fuze of combustible or explosive material which has been placed along the path it will follow.
22. A system as claimed in claim 3, further characterized in that the heating of the air ahead of the projectile is accomplished wholly or partly by combustible or explosive material which has been distributed (as a powder, liquid, vapour or gas) in the atmosphere along the path it will follow.
23. A system as claimed in claim 3, further characterized in that the heating of the air ahead of the projectile is accomplished wholly or partly by, or the air ahead of the projectile is wholly or partly replaced by, the exhaust from a jet or rocket engine.
24. A system as claimed in claim 7, further characterized in that electromagnetic energy fired from a source other than the projectile is focussed into the air ahead of the projectile with the assistance of equipment upon the projectile.
25. A system as claimed in claim 7, further characterized in that electromagnetic energy is absorbed by the air ahead of the projectile with the assistance of a substance (such as a plasma dopant) released into this air.
26. The use of a system as claimed in claim 3 to permit a projectile fired from a ground-based linear accelerator to reach space retaining sufficient speed to permit insertion into Earth orbit or escape trajectory.
27. The use of a system as claimed in claim 3 to permit a projectile fired from a horizontal ground-based linear accelerator and deflected upwards at a shallow angle to reach space retaining sufficient speed to permit insertion into Earth orbit or escape trajectory.
PCT/GB1991/000111 1990-01-26 1991-01-25 Hypervelocity drag reduction WO1991011676A2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9001892.0 1990-01-26
GB909001892A GB9001892D0 (en) 1990-01-26 1990-01-26 A technique for hypervelocity drag reduction by atmospheric heating

Publications (2)

Publication Number Publication Date
WO1991011676A2 true WO1991011676A2 (en) 1991-08-08
WO1991011676A3 WO1991011676A3 (en) 1991-11-14

Family

ID=10670003

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1991/000111 WO1991011676A2 (en) 1990-01-26 1991-01-25 Hypervelocity drag reduction

Country Status (3)

Country Link
AU (1) AU7073291A (en)
GB (1) GB9001892D0 (en)
WO (1) WO1991011676A2 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6830222B1 (en) 2002-03-21 2004-12-14 Global Aerospace Corporation Balloon device for lowering space object orbits
WO2018081559A1 (en) * 2016-10-27 2018-05-03 Ohio University Air data probe
WO2018176157A2 (en) 2017-03-29 2018-10-04 Binek Lawrence A Improved bullet, weapon provided with such bullets, kit for assembling the same, and corresponding methods of manufacturing, operating and use associated thereto
CN109250073A (en) * 2018-09-30 2019-01-22 中国人民解放军国防科技大学 Hypersonic aircraft head drag reduction method based on three-electrode spark discharge thermal jet

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1022913B (en) * 1954-09-15 1958-01-16 Schoppe Fritz Device for generating propulsion or braking on a body moved relative to a flow means
FR1246710A (en) * 1957-04-08 1960-11-25 Aeronautical mobile
US3345948A (en) * 1965-08-03 1967-10-10 John W Sarvis Projectile
CH480615A (en) * 1966-11-08 1969-10-31 Tech Du Verre Tisse S A R L Laminate material coating layer
US3545212A (en) * 1966-12-15 1970-12-08 Dynamit Nobel Ag Spindle-shaped supersonic projectile with additional propulsion by sternfiring
US4014485A (en) * 1975-04-14 1977-03-29 Martin Marietta Corporation Gas cooling system for hypersonic vehicle nosetip

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1022913B (en) * 1954-09-15 1958-01-16 Schoppe Fritz Device for generating propulsion or braking on a body moved relative to a flow means
FR1246710A (en) * 1957-04-08 1960-11-25 Aeronautical mobile
US3345948A (en) * 1965-08-03 1967-10-10 John W Sarvis Projectile
CH480615A (en) * 1966-11-08 1969-10-31 Tech Du Verre Tisse S A R L Laminate material coating layer
US3545212A (en) * 1966-12-15 1970-12-08 Dynamit Nobel Ag Spindle-shaped supersonic projectile with additional propulsion by sternfiring
US4014485A (en) * 1975-04-14 1977-03-29 Martin Marietta Corporation Gas cooling system for hypersonic vehicle nosetip

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6830222B1 (en) 2002-03-21 2004-12-14 Global Aerospace Corporation Balloon device for lowering space object orbits
WO2018081559A1 (en) * 2016-10-27 2018-05-03 Ohio University Air data probe
US11566892B2 (en) 2016-10-27 2023-01-31 Ohio University Air data probe
WO2018176157A2 (en) 2017-03-29 2018-10-04 Binek Lawrence A Improved bullet, weapon provided with such bullets, kit for assembling the same, and corresponding methods of manufacturing, operating and use associated thereto
US11674779B2 (en) 2017-03-29 2023-06-13 Next Dynamics Corp. Bullet, weapon provided with such bullets, kit for assembling the same, and corresponding methods of manufacturing, operating and use associated thereto
CN109250073A (en) * 2018-09-30 2019-01-22 中国人民解放军国防科技大学 Hypersonic aircraft head drag reduction method based on three-electrode spark discharge thermal jet

Also Published As

Publication number Publication date
GB9001892D0 (en) 1990-08-08
WO1991011676A3 (en) 1991-11-14
AU7073291A (en) 1991-08-21

Similar Documents

Publication Publication Date Title
US6488233B1 (en) Laser propelled vehicle
US4938112A (en) Apparatus and method for the acceleration of projectiles to hypervelocities
US8664576B2 (en) Vehicle for launching from a gas gun
RU2719818C2 (en) Directed energy release to facilitate high-speed applications
US20070285304A1 (en) Target orbit modification via gas-blast
US5578783A (en) RAM accelerator system and device
US4014485A (en) Gas cooling system for hypersonic vehicle nosetip
US20230264836A1 (en) Vehicle launch system and method
US4917335A (en) Apparatus and method for facilitating supersonic motion of bodies through the atmosphere
EP0591444B1 (en) Vehicle propulsion system with external propellant supply
US4560121A (en) Stabilization of automotive vehicle
IL82200A (en) Method and apparatus for launching a projectile at hypersonic velocity
US11359877B2 (en) Apparatus and method for accelerating an object via an external free jet
WO1991011676A2 (en) Hypervelocity drag reduction
EP0693668A2 (en) Gas gun launched scramjet test projectile
Tani et al. JAXA RD1 Flight Experiment on Supersonic Combustion: Part 1. Overview
US5791599A (en) System for increasing the aerodynamic and hydrodynamic efficiency of a vehicle in motion
RU2586436C1 (en) Bogdanov method for target destruction and device therefor
Kaloupis et al. The ram accelerator-A chemically driven mass launcher
US3335637A (en) Projectile propelled by friction drag of high velocity plasma
Bruckner et al. Applications of the ram accelerator to hypervelocity aerothermodynamic testing
Schall et al. Ablation performance experiments with metal seeded polymers
Schall et al. Laser propulsion thrusters for space transportation
RU2107010C1 (en) Method of impactness supersonic motion of flying vehicle in atmosphere and flying vehicle for its realization
RU2132037C1 (en) Method lowering aftereffects of interaction of space object with the earth

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AU BB BG BR CA FI HU JP KP KR LK MC MG MW NO PL RO SD SU US

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): AT BE BF BJ CF CG CH CM DE DK ES FR GA GB GR IT LU ML MR NL SE SN TD TG

AK Designated states

Kind code of ref document: A3

Designated state(s): AU BB BG BR CA FI HU JP KP KR LK MC MG MW NO PL RO SD SU US

AL Designated countries for regional patents

Kind code of ref document: A3

Designated state(s): AT BE BF BJ CF CG CH CM DE DK ES FR GA GB GR IT LU ML MR NL SE SN TD TG

NENP Non-entry into the national phase in:

Ref country code: CA