RU2457156C1 - Method and system for catapult seat altitude stabilisation - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: inventions relate to aircraft, in particular to system and method for catapult seat altitude stabilisation. Method for catapult seat altitude stabilisation consists in seat stabilisation along OY and OZ axes using two stabilising parachutes located on stabilising telescopic rods. Stabilisation is additionally performed relative to OX axis by switching on lateral swivel pulse engines from control signal of relay-type angular velocity sensor. Catapult seat altitude stabilisation system contains two stabilising telescopic rods with stabilising parachutes. Relay-type catapult seat angular velocity sensor is additionally incorporated in the system. This sensor outputs control signal to automatics system which controls lateral swivel pulse engines according to updated algorithms.

EFFECT: prevention of catapult seat stability loss and providing descending from high altitudes with acceptable angular velocities of seat movement.

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Description

The invention relates to aircraft, in particular to emergency escape, and may find application in the ejection of flight personnel at high altitudes from aircraft.

The stabilization system should ensure a stable position of the ejection seat during ejection both in the initial section after separation from the aircraft, and later on when descending from high altitudes up to the introduction of a rescue parachute and separation of the pilot from the seat.

There is a method of stabilizing an ejection seat, which consists in stabilizing the seat by introducing a small parachute that is attached to the frame of the seat using a two- or three-link bridle and a 4 m long halyard that allows the parachute to operate outside the aerodynamic trail created by the ejection seat (American ejection seats of the type SIVS, ACESII (DOUGLAS AIRCRAFT COMPANY. Advanced concept ejection seat ACESII. Report MDC J4576 Revision D, March 1988) or English ejection seats of the type Mk12, Mk16 (MARTIN-BAKER'S MK16 ejection seat is the firm's most sophisticated ever. FLIGHT INTERNATIONAL, 18-24 June 1997)).

This method has several disadvantages.

1. The longitudinal dimensions of the soft elements that make up the system - the links of the bridle, connecting halyard, parachute with slings - provide a total length of the deployable structure of 6-8 meters, which requires a sufficiently long time to start its effective operation.

2. With a possible complex spatial angular and linear movement of the aircraft at the time of the accident and the ejection seat with the pilot after the ejection, there is a high probability of contact and possible engagement of such a large soft structure for the elements of the aircraft and the ejection seat.

3. At the most important stage of ejection, at the initial moment when moving near an aircraft, the ejection seat is unstabilized.

4. Due to the small size of the ejection seat, especially the transverse ones, such a system cannot provide the necessary reserves of static stability of the seat along the angles of attack and slip.

There is also a method of stabilizing an ejection seat, adopted for the prototype, which consists in stabilizing the seat by putting two stabilizing parachutes at the ends of two stabilizing telescopic rods (Russian ejection seats of the K-36 type, for example, the K-36D-3.5 seat (Ejection seat K -ZbD-3,5. Manual on technical operation 903-9200-1000.0 OM. Publishing house of OJSC NPP Zvezda, 1999)).

The main disadvantage of these methods of stabilizing the ejection seat is that stabilization is carried out only by parachutes and when descending from high altitudes, a stabilizing aerodynamic moment is provided relative to the associated OY and OZ axes, there is no stabilization along the OX axis (Fig. 1), which can lead to the development of intense angular movement along the roll and subsequent loss of stability relative to other axes. Figure 3 shows the case when when descending from a height of 20 km the chair is stable. However, a descent with a relatively high speed with certain mass-inertial characteristics of the system can lead to the development of angular movement along the roll, which can cause loss if there is a certain aerodynamic asymmetry of the pilot-ejection seat system relative to the longitudinal plane X0Y and the absence of stabilization of the system about the OX axis stability along the sliding angle b (Fig. 4), which will lead to a further decrease in the ejection seat with angular speeds unacceptably large for the pilot yami.

The objective of the invention is the creation of a stabilization system that provides stable stable descent from high altitudes when ejecting flight personnel in the event of an emergency leaving the aircraft.

In accordance with the proposed method, stabilization relative to the OY and OZ axes is carried out by activating stabilizing parachutes located on stabilizing telescopic rods, and relative to the connected axis OX, by switching on pulsed side-turn motors from a control signal supplied by a relay type angular velocity sensor when the catapult reaches the angular position speeds of a certain value relative to the OX axis; moreover, the system operation algorithms are used to generate a signal; so that, depending on the height of the bailout and taking into account the real angular motion relative to the x-axis is defined by the operating mode: For single-seater - roll control for ejection from low altitudes, or parry the angular velocity Wx for ejection at high altitudes; for multi-seat aircraft - trajectory dilution when ejecting from low altitudes, or the delay between the ejection of crew members at high altitudes.

The stabilization system of the ejection seat in accordance with the proposed method contains stabilizing parachutes 2 located on stabilizing telescopic rods 1, side-turn engines 3, an angular velocity sensor of relay type 4 (Fig. 2).

Side-turn engines and existing algorithms for the ejection seat automation system are used when ejecting at low altitudes only for roll control in order to reduce height loss.

In the proposed system, side-turn engines, switched on by a relay sensor signal, in accordance with the developed algorithms of the automation system, provide a one-time parry of the ejection seat developed during the descent from high altitudes.

The system operates as follows.

When ejecting, using information from the aircraft about the flight altitude at the time of the accident, the ejection seat automation system selects the operating mode: it either saves the operating scheme in normal mode or switches to high-altitude mode.

When operating in high-altitude mode for a multi-seat aircraft, the automation system gives a command to increase the time delay between successive bailouts of two crew members, which is implemented by the evacuation logic block located on board the aircraft and begins to analyze the signal of the angular velocity sensor Wx. At the same time, side-turn engines can be switched on only by the control signal of the angular velocity sensor.

Therefore, for both multi-seat and single-seat aircraft, if during the ejection process or subsequent descent from high altitudes the ejection seat acquires an excessively high speed Wx, a control command is generated based on the signal from the angular velocity sensor to turn on one of the two side-turn engines, which parries the development angular velocity Wx. As a result, an impulse decrease in absolute value of this angular velocity occurs by an amount of the order of 5 rad / s, determined by the energy capabilities of the side-turn engines used on the K-36D-3.5 seats.

As shown by numerical estimates of the dynamics of ejection from a height of 20 km, a single decrease in the angular velocity Wx is sufficient to exclude the loss of stability of the ejection seat with its subsequent decrease.

Fig. 5 demonstrates the situation when, when lowering the ejection seat from a height of 20 km, a stabilization system is triggered, which prevents the loss of stability.

Thus, the proposed method and system for stabilizing the ejection seat allows for stable, stable descent from high altitudes during ejection of the flight crew in the event of an emergency exit from the aircraft.

Claims (2)

1. The method of high-altitude stabilization of the ejection seat, including stabilization of the seat along the OY and OZ axes using two stabilizing parachutes located on stabilizing telescopic rods, characterized in that the stabilization is additionally carried out relative to the OX axis by switching on side-turn pulse motors from the control signal of the relay type. 2. The system of high-altitude stabilization of the ejection seat, containing two stabilizing telescopic rods with stabilizing parachutes, characterized in that the system also has an integrated relay for angular velocity of the ejection seat, which supplies a control signal to the automation system, which, in accordance with the developed algorithms, controls pulsed side-turn engines.

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