RU2818924C1 - Returnable upper stage of two-stage carrier rocket and method of its landing - Google Patents

Abstract

FIELD: rocketry; space engineering.

SUBSTANCE: two-stage carrier rocket return upper stage under detachable payload adapter comprises rotor assembly, which provides controlled movement along trajectory of descent from orbit "as per helicopter" in mode of autorotation and bringing of stage to specified area of landing. Rotor blades are laid along the stage body before launching. On stage tail compartment before launching carrier rocket there are four rotary flaps of tail fairing, equipped with longitudinal and transverse power set and controlled pneumatic rod and laid before launching carrier rocket outside along the body of its lower stage. After output of braking pulse of de-orbit, rotor blades are released and their output into working position due to incoming air flow, connection of tail fairing flaps to form a single tail fairing structure and transfer of rotor to autorotation mode and oriented position of stage relative to direction of incoming air flow.

EFFECT: reliable drive of the stage to the specified area.

7 cl, 2 dwg

Description

Technical field

The invention relates to the field of rocket and space technology and can be used in the creation of return stages of fully reusable space launch vehicles.

State of the art

There is a known project of a two-stage ballistic reusable transport space system (BMTKS) (RU2485025 C1), taken as an analogue, intended for launching into orbit an artificial Earth satellite of spacecraft for various purposes, the two-stage BMTKS contains rocket stages with fuel tanks and oxidizer tanks - oxygen, sustainer propulsion systems (PS) and stabilization and orientation propulsion systems, the first stage is cylindrical in shape, equipped with a tail section, an adapter and a fairing, hydrogen is used as fuel for propulsion systems, the tanks of both stages of the system are load-bearing with combined bottoms, and the second stage is made in the form of a truncated cone with spherical bottoms, equipped with thermal protection, both stages are equipped with landing supports. It is known that ballistic descent is accompanied by large overloads and large heat flows to the structure. In addition, there is low landing accuracy. The advantage of the project is that devices with ballistic descent from orbit have been developed in our time. The disadvantage of the project is the large relative mass of the second stage thermal protection, covering its entire side surface and both bottoms, which suggests that this project is applicable only to ultra-light class launch vehicles. However, the benefits from the use of such reusable launch vehicles seem doubtful.

The well-known project of the US private company "SpaceX" (Speech by Elon Musk at the 68th International Astronautical Congress on September 29, 2017) of the reusable spacecraft "Starship", taken as a prototype, is the upper stage of a fully reusable two-stage launch vehicle of the super-heavy class "Super Heavy". The stage has a diameter of 9 m, a length of 50 m with a pointed nose, and is equipped with upper and lower aerodynamic surfaces for control during descent from orbit in the Earth's atmosphere. Thermal protection tiles cover the windward side of the entire stage, its nose and aerodynamic surfaces. Landing is carried out using rocket engines. The stage is designed for landing on the surface of the Earth, Moon and Mars. The advantage of the project is that, due to the large diameter of the step, specially extended supports are sufficient for landing.

Thus, the known technical solutions are unsuitable for creating a returnable upper stage of a two-stage light and medium class launch vehicle and a method for landing it.

The reason preventing the solution of the technical problem of creating a returnable upper stage of a two-stage light and medium-class launch vehicle and a method for landing it is the absence to date of projects for a returnable upper stage and methods for landing it that would ensure the necessary reliability of bringing the stage to a given area and suitable for implementation, the cost of which would be economically justified.

Disclosure of the invention

The design of the return upper stage of a two-stage light and medium-class launch vehicle and a method for its landing are proposed, obtained as a result of the use of a main rotor assembly for controlled movement along the trajectory of descent from orbit “like a helicopter” in autorotation mode and bringing the stage to a given landing area, application four-flap tail fairing of the stage to protect it from thermal and mechanical loads when the stage moves along the descent path and use the tail fairing flaps as landing supports when landing the stage.

A. A design is proposed for the returnable upper stage of a two-stage launch vehicle, containing a cylindrical body with tandemly located load-bearing oxidizer and fuel tanks in the middle part, a detachable payload adapter of a truss structure installed on the upper frame of the front shell, a tail compartment with a methane propulsion liquid rocket engine located in it (LPRE) in a two-stage gimbal suspension with thrust throttling. The stage is equipped with orientation, navigation and motion control systems with steering thrusters. A main rotor assembly is installed under the detachable payload adapter, which ensures controlled movement along the trajectory of descent from orbit “like a helicopter” in autorotation mode and bringing the stage to a given landing area. Before the launch of the launch vehicle, four rotating tail fairing flaps are installed on the tail section of the stage, providing reliable protection of the tail section from thermal and mechanical loads when the stage moves at hypersonic speed along the descent trajectory with the tail section in the direction of the velocity vector. After passing through the dense layers of the atmosphere and opening, the tail fairing flaps are used as landing supports during landing. The power set of tanks, inter-tank space and shells of the stage body is made of steel, coated on the outside with ceramic lining with intermediate layers of thermal insulation made of titanium foil. Controlled valves are used to cool the main rotor assembly with cold gas from the upper liquid oxygen tank.

b. The main rotor assembly consists of a stationary power tube installed on the base, in which is fixed a rotating tube with a main rotor hub fixed on top of it, capable of rotating together with the blades fixed in the hub in the descent section in autorotation mode, while controlling the overall and cyclic pitch of the blades they are inserted into the bushing by their axial hinge. To ensure rotation of the blade relative to the hinge axis, a reversible stepper motor is used, inserted into the bushing along with a blade rotation angle sensor. A stationary pipe is fixed inside the rotating pipe, passing through the rotating sleeve and ending with a stationary platform for placement on it under the radio-transparent radome of the antenna of the consumer equipment of the global navigation positioning system.

c. The main rotor blades, their power elements and casing are made of titanium; before the launch of the launch vehicle they are in a rotated position relative to their horizontal hinges and are laid under the head fairing of the launch vehicle along the stage body and secured in the end parts using brackets with pyrolocks, when In this case, the vertical hinge of the blade is located between the axial and horizontal hinges.

d. The rotating flaps of the tail fairing are equipped with spring-loaded elements of a split collar, a longitudinal and transverse power set and a controlled pneumatic rod and are laid before the launch of the launch vehicle from the outside along the body of its lower stage and secured in the end parts with brackets with pyrolocks.

e. After the separation of the lower stage, before turning on the main liquid rocket engine of the upper stage, the tail fairing flaps have the ability to deviate at a given angle from the position they occupied during the operation of the main liquid propellant rocket engine of the lower stage, in order to exclude the possibility of gas jets from the operating main liquid propellant engine hitting the flaps. Before the upper stage enters the dense layers of the atmosphere, the flaps are connected with an overlap relative to each other, with each upper flap providing a connection with two adjacent lower ones to form a tightly closed fairing structure with locking with reusable locks, providing reliable protection of the tail section of the stage from thermal and mechanical loads when the stage moves at hypersonic speed along the descent trajectory with the tail section in the direction of the motion velocity vector.

f. To use the tail fairing flaps as stage landing supports, the tail section in the area of the critical section of the sustainer liquid-propellant rocket engine nozzle contains a power frame with rods, and the power set of flaps contains hooks that ensure engagement with the rods of the power frame after opening the flaps before turning on the propulsion liquid-propellant engine for landing, fixation with reusable locks and keeping the doors open after landing.

g. The method for landing the re-entry upper stage of a launch vehicle comprises control operations in the extra-atmospheric stage of descent from orbit with the issuance of a braking velocity pulse using a main liquid-propellant rocket engine when the stage is oriented by the engine in the direction of the motion velocity vector. After issuing a braking pulse, while maintaining the same orientation of the stage, the main rotor blades are released and brought into working position due to the incoming air flow, the tail fairing flaps are connected to form a single tail fairing structure, and the main rotor is switched to the autorotation mode and the oriented position of the stage relative to the direction incoming air flow. Before entering the dense layers of the atmosphere, constant set rotor speeds are maintained by controlling the overall pitch of the blades. Before the section of the trajectory with a high speed pressure, the blades are raised upward into a feathered position and the main rotor assembly is blown with cold gas. After the transition to a section of the trajectory with an established reduced velocity pressure and a reduced vertical descent speed, the overall and cyclic pitch of the blades is simultaneously controlled to ensure the necessary reliability of bringing the stage to the specified landing area, the tail fairing flaps are opened before turning on the sustainer rocket engine to issue a braking impulse for a soft landing at the specified a position in which, after issuing a braking impulse, they are used as landing supports.

The objective of this invention is to develop a returnable upper stage of a two-stage launch vehicle and a method for landing it based on the use of a main rotor assembly for controlled movement along the trajectory of descent from orbit “like a helicopter” in autorotation mode and bringing the stage to a given landing area, using a four-leaf tail stage fairing to protect it from thermal and mechanical loads when the stage moves along the descent path and to use the tail fairing flaps as landing supports when landing the stage.

The problem is solved by the fact that the return upper stage of a two-stage launch vehicle, containing a cylindrical body with tandemly located load-bearing tanks of oxidizer and fuel in the middle part, a detachable payload adapter of a truss structure installed on the upper frame of the front shell, a tail compartment with a methane tank located in it propulsion liquid rocket engine (LPRE) in a two-stage gimbal suspension with thrust throttling, orientation, navigation and motion control systems with steering attitude control jet engines, according to the invention, a main rotor assembly is installed under the detachable payload adapter, providing controlled movement along the descent trajectory from orbit “along -helicopter" and bringing the stage to a given landing area, and on the tail section of the stage before the launch of the launch vehicle, four rotating tail fairing flaps are installed, providing reliable protection of the tail section from thermal and mechanical loads when the stage moves at hypersonic speed along the descent trajectory with the tail section along direction of the velocity vector and after passing through dense layers of the atmosphere and opening, they are used as landing supports during landing, while the power set of tanks, intertank space and shells of the stage body is made of steel, coated on the outside with ceramic lining with intermediate layers of thermal insulation made of titanium foil, and for Controlled valves are used for cooling when the main rotor assembly operates with cold gas from the upper liquid oxygen tank.

The main rotor assembly consists of a stationary power tube installed on the base, in which is fixed a rotating tube with a main rotor hub fixed on top of it, capable of rotating together with the blades fixed in the hub in the descent section in autorotation mode, while controlling the overall and cyclic pitch of the blades they are inserted into the bushing with their axial hinge, and to ensure rotation of the blade relative to the hinge axis, a reversible stepper motor is used, inserted into the bushing along with a blade rotation angle sensor; a stationary pipe is fixed inside the rotating pipe, passing through the rotating bushing and ending with a stationary platform for placement on it under the radio-transparent radome of the antenna of the consumer equipment of the global navigation positioning system.

The main rotor blades, their power elements and casing are made of titanium; before the launch of the launch vehicle they are in a rotated position relative to their horizontal hinges and are laid under the head fairing of the launch vehicle along the stage body and secured in the end parts using brackets with pyrolocks, when In this case, the vertical hinge of the blade is located between the axial and horizontal hinges.

The rotating flaps of the tail fairing are equipped with spring-loaded elements of a split collar, a longitudinal and transverse power set and a controlled pneumatic rod and are laid before the launch of the launch vehicle from the outside along the body of its lower stage and secured in the end parts with brackets with pyrolocks.

After the separation of the lower stage, before turning on the main liquid propellant engine of the upper stage, the tail fairing flaps have the ability to deviate at a given angle from the position they occupied during the operation of the main liquid propellant engine of the lower stage, to exclude the possibility of gas jets from the operating main liquid propellant engine hitting the flaps, and before the entrance of the upper stage in the dense layers of the atmosphere, the flaps are connected with an overlap relative to each other, while each upper flap provides a connection with two adjacent lower ones to form a tightly closed tail fairing structure with locking with reusable locks, providing reliable protection of the tail section of the stage from thermal and mechanical loads during the movement of the stage with hypersonic speed along the descent trajectory with the tail section in the direction of the movement speed vector.

To use the tail fairing flaps as stage landing supports, the tail section in the area of the critical section of the sustainer liquid-propellant rocket engine nozzle contains a power frame with rods, and the power set of flaps contains hooks that ensure engagement with the rods of the power frame after opening the flaps before turning on the propulsion liquid-propellant engine for landing, fixation with reusable locks and keeping the doors open after the step lands.

A method for landing the re-entry upper stage of a launch vehicle, containing control operations in the extra-atmospheric stage of descent from orbit with the issuance of a braking impulse of speed using a main liquid propellant engine when the stage is oriented by the engine in the direction of the velocity vector, according to the invention, after issuing a braking impulse while maintaining the same orientation of the stage the main rotor blades are released and brought into operating position due to the oncoming air flow, the tail fairing flaps are connected to form a single tail fairing structure and the main rotor is switched to the autorotation mode and the oriented position of the stage relative to the direction of the oncoming air flow, maintaining constant specified rotor speeds before entering the dense layers of the atmosphere by controlling the general pitch of the blades, lifting the blades up into the feathering position and blowing the main rotor assembly with cold gas before the trajectory section with a high speed pressure, after moving to the trajectory section with a steady reduced speed pressure and a reduced vertical descent rate, simultaneous control of the general and cyclic pitch of the blades to ensure the necessary reliability of bringing the stage to a given landing area, opening the tail fairing flaps before turning on the main rocket engine to issue a braking impulse for a soft landing in a given position, in which, after issuing a braking impulse, they are used as landing supports.

The essence of the invention is illustrated by two drawings.

In fig. Figure 1 shows a diagram of part of a two-stage launch vehicle with the main rotor assembly and tail fairing flaps installed on it before launch.

In fig. Figure 2 shows the position of the unfolded tail compartment flaps before landing and a view along the arrow from below of the load-bearing frame.

In these drawings:

1 - lower stage of the launch vehicle;

2 - tail fairing flap;

3 - connecting frames of steps;

4 - upper stage propulsion rocket engine nozzle;

5 - split collar with spring-loaded elements;

6 - upper stage of the launch vehicle;

7 - main rotor hub;

8 - horizontal hinge;

9 - vertical hinge;

10 - radio-transparent fairing;

11 - receiving antenna;

12 - base;

13 - main rotor blade;

14 - main rotor blade mounting bracket;

15 - bracket for fastening the tail fairing flap;

16 - tail fairing flap in the open state;

17 - power set of the tail fairing flap;

18 - controlled pneumatic rod;

19 - hinge for fastening the controlled pneumatic rod;

20 - hinge for rotation of the tail fairing flap;

21 - hook for fastening the tail fairing flap to the load-bearing frame;

22 - power frame.

Carrying out the invention

An example of a possible implementation of the proposed technical solution

The returning upper stage of the two-stage launch vehicle (Fig. 1) is docked with the lower stage 1, along the body of which the tail fairing flaps 2 are laid. The dotted line shows the connection of the flaps into a single tail fairing structure. The docking is carried out using the connecting frames of stages 3. The nozzle 4 of the upper stage propulsion rocket engine partially enters the upper shell of the lower stage. The spring-loaded elements of the split collar 5 protect the tail fairing flaps from high speed pressure during launch vehicle launch. The upper stage 6 of the launch vehicle in its upper part carries a main rotor assembly, which consists of a main rotor hub 7, into which elements are inserted that ensure free movement of the blade in autorotation mode, consisting of a horizontal hinge 8 and a vertical hinge 9. The axial hinge is included in main rotor hub (not shown in Fig. 1). Under the radio-transparent radome 10 there is a receiving antenna 11 of the consumer equipment of the global navigation positioning system. The main rotor assembly is placed on a base 12 mounted on the frame of the upper shell of the upper stage. The main rotor blades 13 are laid along the stage body and secured at the end parts using brackets 14 with pyrolocks. The tail fairing flaps 2 are secured at the end parts with brackets 15 with pyrolocks. The tail fairing flap 16 (Fig. 2) has a longitudinal and transverse power set 17 and folds and unfolds using a controlled pneumatic rod 18, fixed to the tail section of the upper stage using a hinge 19. The tail fairing flap 16 is attached to the tail section of the upper stage using hinge 20, and with the help of two hooks 21 it engages and is fixed with reusable locks (not shown in Fig. 2) with the rods of the load frame 22 installed in the area of the critical section of the nozzle 4 of the upper stage propulsion rocket engine.

The return upper stage has the following characteristics. The diameter of the cylindrical part of the body is 4.1 m, the length is 12 m, the mass of the stage at the moment it touches the ground is 12.5 tons. The length of the main rotor blades is 6.0 m, the width is 0.3 m. The length of the tail fairing flap is 8 m .

As a result of the application of the present invention, a technical solution aimed at developing a returnable upper stage of a two-stage launch vehicle and a method for landing it and reducing the cost of operating the stage is implemented through the use of a main rotor assembly for controlled movement along the descent trajectory from orbit “in a helicopter” mode autorotation and bringing the stage to a given landing area, the use of a four-wing tail fairing of the stage to protect it from the action of thermal and mechanical loads when the stage moves along the descent trajectory and the use of tail fairing wings as landing supports when landing the stage.

Claims (7)

1. Returnable upper stage of a two-stage launch vehicle, containing a cylindrical body with tandemly located load-bearing tanks of oxidizer and fuel in the middle part, a detachable payload adapter of a truss structure installed on the upper frame of the front shell, a tail compartment with a methane propulsion liquid rocket engine located in it (LPRE) in a two-stage gimbal suspension with thrust throttling, orientation, navigation and motion control systems with steering attitude control jet engines, characterized in that a main rotor assembly is installed under the detachable payload adapter, providing controlled movement along the trajectory of descent from orbit “like a helicopter” "and bringing the stage to a given landing area, and on the tail section of the stage before the launch of the launch vehicle, four rotating tail fairing flaps are installed, providing reliable protection of the tail section from thermal and mechanical loads when the stage moves at hypersonic speed along the descent trajectory with the tail section in the direction of the vector speed of movement and after passing through dense layers of the atmosphere and opening, they are used as landing supports during landing, while the power set of tanks, intertank space and shells of the stage body is made of steel, coated on the outside with ceramic lining with intermediate layers of thermal insulation made of titanium foil, and for cooling at Controlled valves are used to operate the main rotor assembly with cold gas from the upper liquid oxygen tank. 2. The stage according to claim 1, characterized in that the main rotor assembly consists of a stationary power pipe installed on the base, in which is fixed a rotating pipe with a main rotor hub fixed on top of it, capable of rotating together with the blades fixed in the hub in the descent section autorotation mode, while to control the general and cyclic pitch of the blades, they are inserted into the bushing with their axial hinge, and to ensure rotation of the blade relative to the hinge axis, a reversible stepper motor is used, inserted into the bushing along with a blade rotation angle sensor, a stationary pipe is fixed inside the rotating pipe, passing through a rotating bushing and ending with a stationary platform for placement on it under the radio-transparent radome of the antenna of the consumer equipment of the global navigation positioning system. 3. The stage according to claim 2, characterized in that the main rotor blades, their power elements and casing are made of titanium; before the launch of the launch vehicle they are in a position rotated relative to their horizontal hinges and are laid under the head fairing of the launch vehicle along the body of the stage and secured in the end parts using brackets with pyrolocks, while the vertical hinge of the blade is located between the axial and horizontal hinges. 4. The stage according to claim 3, characterized in that the rotary flaps of the tail fairing are equipped with spring-loaded elements of a split collar, a longitudinal and transverse power set and a controlled pneumatic rod, and are laid before the launch of the launch vehicle from the outside along the body of its lower stage, and are fixed in the end parts with brackets with pyrolocks. 5. The stage according to claim 4, characterized in that after the separation of the lower stage, before turning on the propulsion rocket engine of the upper stage, the tail fairing flaps have the ability to deviate by a given angle from the position they occupied during the operation of the propulsion rocket engine of the lower stage, to exclude the possibility of hitting the flaps jets of gases from the operating propulsion rocket engine, and before the upper stage enters the dense layers of the atmosphere, the flaps are connected with an overlap relative to each other, with each upper flap providing a connection with two adjacent lower ones to form a tightly closed tail fairing structure with locking with reusable locks, ensuring reliable protection of the tail section of the stage from thermal and mechanical loads when the stage moves at hypersonic speed along the descent trajectory with the tail section in the direction of the velocity vector. 6. The stage according to claim 5, characterized in that in order to use the tail fairing flaps as landing supports of the stage, the tail compartment in the area of the critical section of the nozzle of the main liquid-propellant rocket engine contains a power frame with rods, and the power set of flaps contains hooks that ensure engagement with the rods of the power frame after opening the flaps before turning on the propulsion rocket engine for landing, fixing with reusable locks and holding the flaps in the open state after landing of the stage. 7. A method of landing the return upper stage of a launch vehicle, containing control operations in the extra-atmospheric stage of descent from orbit with the issuance of a braking impulse of speed using a main liquid propellant engine when the stage is oriented by the engine in the direction of the speed vector, characterized in that after issuing a braking impulse while maintaining that same stage orientation, the main rotor blades are released and brought into operating position due to the oncoming air flow, the tail fairing flaps are connected to form a single tail fairing structure and the main rotor is switched to the autorotation mode and the oriented position of the stage relative to the direction of the oncoming air flow, maintaining constant set values revolutions of the main rotor before entering the dense layers of the atmosphere by controlling the overall pitch of the blades, lifting the blades up into the feathered position and blowing the main rotor assembly with cold gas before the trajectory section with a high speed pressure, after moving to the trajectory section with a steady reduced speed pressure and a reduced vertical speed During the descent, the general and cyclic pitch of the blades is simultaneously controlled to ensure the necessary reliability of bringing the stage to a given landing area, the tail fairing flaps are opened before turning on the main rocket engine to issue a braking impulse for a soft landing in a given position, in which, after issuing a braking impulse, they are used as landing supports .