JP2627831B2 - Aerospacecraft - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to aircraft protection systems,
In particular, it relates to a crew protection system for safely evacuating aircraft, especially hypersonic vehicles, in emergency situations, for example in the case of uncontrolled failures or explosions of the main fuel tank.

[0002] The prior art to date has not addressed the problem of protecting aircraft crew from the effects of sudden overpressure caused by catastrophic failure of the fuel or propellant tanks of the fuselage. . The prior art mainly deals with controlled or dedicated systems for removing the crew cabin from the rest of the aircraft in an emergency, but for reasons of uncontrollable catastrophic failure of the vehicle due to the explosion of the propellant tank. It does not address the means to activate or activate the crew escape system. Furthermore, the current concept of crew protection imposes unacceptable disadvantages on weight and is not cost effective.

[0003] US Patent No. 4,580,746 discloses a capsule and rocket extraction system that provides an in-flight escape system to a damaged aircraft pilot, which system sequentially operates the capsule extraction device. Means for separating the capsule from the main fuselage and then operating the rocket to remove the pilot from the capsule.

Another exemplary prior art showing various types of crew escape mechanisms for aircraft is disclosed in US Pat.
No. 3,265, No. 3,377,037, No. 3,37
No. 4,965, No. 2,941,764, No. 3,06
7,973 and 2,977,080.

[0005] Each of the above patented escape systems includes:
Identify propulsion units for crew compartment separation. Generally, the prior art deals with a dedicated extraction system, such as a dedicated rocket, to operate the crew escape system.

It is therefore an object of the present invention to provide an escape system for crew protection of aircraft, especially hypersonic vehicles, under catastrophic airframe conditions.

[0007] Another object is to provide a crew protection system for an aircraft in the event of an uncontrollable catastrophic failure or explosion of the main fuel tank.

[0008] Yet another object is to provide a means for allowing the crew to escape from the aerospace vehicle,
In an emergency situation due to an uncontrollable failure or explosion of the main fuel tank, the crew carrying capsule is allowed to leave the rest of the fuselage, thereby allowing the crew to use, especially at hypersonic speeds, dedicated rockets Provides weight savings over prior art methods of personnel protection.

[0009] Other objects and advantages of the invention will become apparent from the following description of the invention.

[0010]

SUMMARY OF THE INVENTION The crew protection system of the present invention is designed to isolate aircraft crew from hazards, particularly catastrophic failure of fuel tanks, and to provide hypersonic speeds in such emergency situations. Means to safely evacuate the vehicle. The crew cabin is located in the front fuselage of the fuselage body. The forward fuselage is designed to be completely separated from the fuselage body in the event of a catastrophic failure of the body's fuel tank, such as from the burning of propellant, and the crew will remain unaffected during such dangerous situations. Protect. The forebody separation system produces simultaneous virtual circumferential disruptions during catastrophic tank explosions. The system allows the energy released by such a fuel tank failure to separate the forebody from the master without structural separation delays. This ensures that the forebody is separated from the parent machine without inducing any unwanted pitch or roll momentum.

Thus, in the event of an uncontrolled failure of the main tank or combustion of the propellant, the resulting impact forces the forebody to separate from the rest. The forebody is designed to withstand the worst case uncontrollable failure modes. As an additional feature, it is possible to cause the forebody to separate from the body by causing a controlled destruction of the main tank.

The system of the present invention is unique in protecting crews in situations where there is not enough preparation time to begin escape. In addition, the separation of the forebody from the fuselage body does not require a dedicated rocket motor for separation, so that considerable weight savings are obtained and therefore the system of the present invention is cost effective.

The shape and physical properties of the forebody, and the materials used in its construction, mitigate the effects of explosive pressure shocks. In addition, the forward fuselage protects the crew from both explosive heat and aerodynamic heating experienced during subsequent orbits. The forebody is designed to be stable during both the transitional period immediately after the explosion and the subsequent free-fall condition. For high altitude / high speed escape situations, the crew will descend to a lower altitude in the forebody. At a preselected altitude and terminal speed, the crew would then be able to evacuate the forebody using a conventional ejection seat.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENT The forebody separation concept of the present invention uses the overpressure of a tank explosion to separate and propel the forebody. The separation device uses a predictable failure of the main structure to completely cut off the fuselage and separate the forebody.

Referring to FIG. 1 of the drawings, the numeral 10 represents a hypersonic aircraft having a forebody or forebody capsule 12 and a rear fuselage 14. The front fuselage or the front fuselage capsule 12 and the rear fuselage 14 constitute a “body body” of the present invention.

Referring to FIG. 2 of the drawings, the front fuselage 12 includes a crew compartment 16 having a conventionally designed ejection seat 18.
The front body 12 refers to a portion from the nose 36 to the separation surface 42, as is clear from FIGS. 2, 3, 5, and 6. The forebody is constructed of explosive structures to provide protection from catastrophic structural failure due to fuel tank explosions. Therefore, the pressure bulkhead 2 in the crew compartment
Baffle including 0 and rear pressure bulkhead 22
And an avionics compartment 24 is located between the bulkheads and behind the crew compartment 16. A fuel or propellant tank 26 is located in the fuselage 14 directly behind the front fuselage 12. Fuel tank 26 includes a baffle such as 28 and end cap 30 immediately behind avionics compartment pressure bulkhead 22. Main fuel tank 2
Baffles such as 28 in 6, end caps 30 on the fuel tank, front fuselage bulkheads 20 and 22, etc., are designed to protect the crew from risks such as main tank failure. The partitions 20, 22, and 28 and the end cap 30 define a front portion between the crew compartment and the fuel tank to protect the crew and mitigate a fuel tank failure explosion. A "baffle system in the rear of the fuselage" is configured.

The attitude control system 32 is mounted on the forebody 12 and provides a means of very quickly stabilizing the forebody once activated during escape following the forebody separation. An environmental control and life support system 34 is also provided. Thermodynamic heating of the forebody limits the performance envelope of the forebody for escape if no provision is made for cooling. In this case, the "envelope" means a range including a limit at which the aircraft can be safely and efficiently operated, and therefore, the "performance envelope" simply means a "limit of performance". For this purpose, an active cooling system, for example shown at 37 for high performance cooling, is provided at the nose 36 of the forebody. Injection seat 1
8 provides a means to evacuate the forebody in case of low altitude, low speed escape situations, and also to evacuate from the crew cabin and forebody after separation from the main fuselage following a catastrophic fuel tank explosion. It can also be used to cause

Referring to FIG. 3, one embodiment of the complete passive separation system of the present invention is shown, which separates the forebody from the master unit by relying entirely on the overpressure of the explosion. To allow complete structural disconnection. Numerals 38 and 40 illustrate the main structural members between the front fuselage 12 and the main fuselage just behind the fuel tank end caps 30. The main structural members 38 and 40 comprise a plurality, here two, Individually, they are connected together at a separation surface 42 by joint fasteners 44. A joint guillotine 46 is provided on a support member 48, which is connected to a pressure sensing mechanism (not shown), which applies upon application of a predetermined overpressure, such as from a catastrophic fuel tank explosion. The guillotine is actuated to sever the structural fastener 44, the application of which is sensed by a pressure sensing mechanism to sever the structural fastener 44 and to disengage the main structural members 38 and 40 and the associated front along the separation surface 42. The body 12 and the fuselage 14 are separated. The joint fastener 44, the joint guillotine 46, and the pressure detection mechanism are provided between the body and the front body of the aerospace machine according to claim 1.
In the case of an uncontrollable catastrophic failure of the fuel tank, causing a substantial circumferential structural break between the forebody and the fuselage body in response to the explosion pressure due to the catastrophic failure of the fuel tank A separating means for separating the front body and the crew compartment from the body of the aircraft is configured. In addition, the joint guillotine 46 corresponds to “means capable of cutting the fastener” in claim 4, and the pressure detection mechanism operates the cutting means in response to the explosion pressure due to the catastrophic failure of the fuel tank in claim 4. Operating means ". The plurality of guillotine-type separation systems illustrated in FIG. 3 are provided in equally spaced relation about the periphery of separation surface 42, the purpose of which is to provide simultaneous separation surface 42 during catastrophic tank explosion. It is a simultaneous start to create a structural break on the circumference. This system allows the front fuselage to be mounted without any structural delays.
Allowed to separate from This ensures that the forebody is separated from the parent machine without inducing any unwanted pitch or roll momentum. Therefore,
This type of structural failure provides "complete" separation of the forebody from the main fuselage.

Another means of separating the forebody during a catastrophic explosion without relying on crew reaction can utilize a pressure sensing device, which can be a pyrotechnical device.
Activate an icdevice or other system to provide a complete structural disconnect between the forebody and the main fuselage.

Referring to FIG. 4, control of the aerodynamic or streamlined shape of the forebody 12 and the location of the center of gravity of the forebody provide stability and control of the forebody after separation from the main fuselage. Important for. The inherent characteristic of a hypersonic front body, preferably combined with a center of gravity at 50, located about 65% of the length of the front body from the nose 36, is a pressure center 52 behind the center of gravity. Position and a slight vertical bias between the center of gravity and the center of pressure, along with stability of the forebody during separation and descent. Roll control and attitude stability are provided by an attitude control system (ACS) 32. Additional stabilizers for the forebody, such as deployable forebody flaps or deceleration parachutes, can also be used if desired.

Even if there is a catastrophic failure of the fuselage body which drops rapidly due to explosion or combustion due to the combination of either a propellant such as liquid hydrazine with the surrounding air in the fuel tank or an oxidizer loaded in the machine, The resulting pressure pulse will propagate rapidly, but will give little warning prior to structural failure of the tank. This results in uncontrolled separation of the forebody 12 and the crew compartment therein from the main body 14. Such pressure pulses sensed by the pressure sensing mechanism actuate the joint guillotine 46 to sever the structural fastener 44, resulting in a complete circumferential structural break along the separation surface 42, and There is a momentary separation of the forebody 12 from the main fuselage 14, as shown in FIG. 5 of the drawings. Since there is not enough time for a reaction to occur during such a failure, the protection must be in place and ready to operate before the failure. Baffles such as 28 in the fuel tank 26, tank end caps 30 and bulkheads 20 and 22 in the forebody 12 reduce explosions associated with the burning of propellants loaded onboard the aircraft and reduce crew acceleration. Prevent human limits.

Referring to FIG. 6, there is shown a separate forebody 12 following the explosion shown in FIG.
It is noted that the separation from 4 occurs along separation surface 42, giving a "complete" disconnection of the forebody away from the fuselage.

Referring to FIG. 7, front body 12 immediately after separation
And the position of the fuselage 14, once the pressure impact forces the front fuselage 12 away from the rest of the fuselage body 14,
Due to aerodynamic forces, the relative separation between the front body 12 and the body 14 continues to increase. Once separated, the forebody is streamlined to have a higher ballistic coefficient than the rest of the body. Here, the “ballistic coefficient” is a parameter that defines the relationship between weight and drag. Therefore, the remaining body 14 decelerates at a faster rate than the front body. The cutting opening 53 of the body 14 shown in FIG. 7 greatly increases the drag,
The dragged engine (stops after the explosion) rocks the aircraft vertically to help separate it. Wings 54 increase lift and drag until they stop working. Control of the forebody 12 during descent can be achieved by using the attitude control system 32 and carefully designing the center of gravity 50 of the forebody relative to the center of pressure 52. By incorporating a slight vertical bias between the center of gravity of the forebody and the center of pressure, the forebody, as noted above, has a small angle of attack without the need for specialized deployable wings. Can be stable. A small nose jet (not shown) at the nose 36 of the forebody aids in a safe ejection flight regime during descent. Immediately after separation, the forebody 12 begins to decelerate sharply, the forebody freely falls to a lower altitude, and allows a safe ejection of the crew from the crew compartment by the ejection seat 18. Slow down to The ejection seat 18 corresponds to claim 5 "an ejection seat operable to evacuate a crew member at a preselected altitude and separation speed".

Optionally, additional means may be provided to cause a controlled failure of the fuel tank and to initiate or assist in separating the forebody and crew compartment from the body. Referring to FIG. 2, a shaped explosive (shaped cha)
rge) 56 may optionally be provided externally on body 10 adjacent separation surface 42. Accelerometers and strain gauges throughout the fuselage continuously monitor pitch and roll and the condition of the fuselage structure. If it is determined that a catastrophic vehicle failure is imminent or has already occurred, the escape system of the present invention is activated by actuation of explosive 56 from the crew compartment to initiate a controlled explosion of propellant in tank 26. Erection to ensure complete disconnection and active separation along the substantially circumferential structural break between the forebody and the remainder of the fuselage. If an explosion in tank 26 had previously occurred, the separation bomb serves to cut off the rear edge of the forebody. This explosive 56
Corresponds to claim 6 "explosion means for causing a controlled explosion of the fuel tank by its operation to start or assist the separation of the front body and the crew from the body of the body".

From the foregoing, it can be seen that the present invention provides a simple and practical method for escaping a crew from an aerospace vehicle traveling at varying speeds in the event of an uncontrolled failure of the main fuel tank due to propellant combustion or explosion. Providing a means and providing weight savings compared to the prior art which proposed a method of crew protection utilizing a controlled system such as a rocket to separate the crew capsule from the body. Recognize.

Since various modifications of the present invention will occur to those skilled in the art, the present invention is not to be considered as limiting except as by the appended claims.

[Brief description of the drawings]

FIG. 1 illustrates a hypersonic aircraft having a separable front fuselage capsule in accordance with the present invention.

FIG. 2 is a detailed horizontal cross-sectional view of a separable front fuselage of the aircraft of FIG.

FIG. 3 is a line 3 in FIG. 2 showing a passive separation system for separating the forebody from the main fuselage of the aircraft during a sudden increase in pressure, such as due to an explosion of the main fuel tank of the aircraft.
FIG. 3 is an enlarged cross-sectional view cut off at −3.

FIG. 4 illustrates preferred locations of the center of gravity and center of pressure of the forebody to provide stability to the forebody during separation and descent.

5 is a diagram illustrating a catastrophic explosion of a fuel tank of the hypersonic aircraft of FIG. 1;

FIG. 6 illustrates the acceleration of the forebody away from the fuselage of the aircraft following the separation explosion in FIG.

FIG. 7 illustrates the front airframe after separation of the front airframe propelling a crew capsule contained in the front airframe away from the exploding rear airframe portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Aerospace aircraft 12 Front fuselage 14 Main fuselage 16 Crew room 18 Ejection seat 26 Main fuel tank 32 Attitude control system 36 Nose 50 Center of gravity 52 Pressure center

 ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Harry A. Scott, United States, 90250, Hawthorne, West Wanhand Dread and Twenty Second Street, 5546

Claims (6)

(57) [Claims] 1. An aerospace vehicle comprising: a fuselage body having a fuel tank adapted to contain fuel; and a front fuselage coupled to the fuselage body, wherein the front fuselage includes a crew compartment. A system for protecting a crew in the event of a catastrophic failure of the fuel tank due to burning of fuel therein, the crew protecting the crew and mitigating an explosion of failure of the fuel tank. A baffle system in the rear of the forebody between the chamber and the fuel tank; and a baffle system provided between the body and the forebody of the aerospace vehicle for uncontrollable catastrophic control of the fuel tank. In the event of a major failure, in response to the explosive pressure resulting from the catastrophic failure of the fuel tank, a substantially circumferential structural break is created between the forebody and the body of The aircraft and the crew compartment And a separating means for separating from the body main body, crew protection system. 2. An end cap on the fuel tank adjacent to a rear end of the forebody and the baffle system in the forebody, and baffle means provided in the fuel tank. The aerospace vehicle according to claim 1. 3. The forebody is streamlined, has a nose at a forward end, and has a center of gravity about 65% of the length of the forebody from the nose. 2. The center of pressure, at which the line of action of the force on the airfoil, which is in the form of a wing cut from the fluid, intersects the chord, behind the center of gravity and slightly vertically offset from the center of gravity. The aerospace vehicle described in the above. 4. An aerospace vehicle comprising an airframe body and having a fuel tank adapted to contain fuel and a front airframe coupled to the airframe body, wherein the front airframe includes a crew compartment. A crew protection system in the event of a catastrophic failure of the fuel tank due to the combustion of fuel therein, the crew being provided with main structural members on the fuselage body and the front fuselage; and A baffle system in the rear of the front fuselage between the crew compartment and the fuel tank to mitigate a fuel tank failure explosion; and between the main body and adjacent main structural members of the front fuselage. A crew protection system comprising: a plurality of fasteners; means capable of cutting the fasteners; and means for activating the cutting means in response to explosive pressure due to the catastrophic failure of the fuel tank. 5. An ejection seat in the crew compartment operable to evacuate a crew member from the crew compartment at a preselected altitude and separation speed after separation of the forebody from the fuselage body. The aerospace vehicle according to claim 1. 6. An aerospace vehicle comprising an airframe body and having a fuel tank adapted to contain fuel and a front airframe coupled to the airframe body, wherein the front airframe includes a crew compartment. A crew protection system in the event of a catastrophic failure of the fuel tank due to the burning of fuel therein, the crew protecting the crew and mitigating an explosion of failure of the fuel tank. A baffle system in the rear of the forebody between the crew compartment and the fuel tank; and an uncontrollable destruction of the fuel tank provided between the body and the forebody of the aerospace vehicle. In the event of a catastrophic failure, in response to the explosion pressure due to the catastrophic failure of the fuel tank, causing a substantially circumferential structural break between the front fuselage and the fuselage body, Front aircraft and the crew cabin Separating means for separating from the aircraft body, the actuation of which causes a controlled explosion of the fuel tank to initiate or assist the separation of the forebody and the crew from the aircraft body. Crew protection system, including explosive means.