Single stage inboard catapult launching system simulation

Аuthors

Pravidlo M. N., Belyaev A. N.^*, Kosarev A. V.^**

Toropov Machine-Building Design Bureau "Vimpel", 90, Volokolamskoe shosse, Moscow, 125424, Russia

*e-mail: Alex_JC@mail.ru
**e-mail: Kosarevav420@mail.ru

Abstract

The aircraft-carriers (AC) of the fifth generation are characterized by intrafuselage accommodation of aircraft guided missiles (AGM), which is essential for the improved operational and physical characteristics of the aircraft, by maintaining its aerodynamic efficiency and reducing the radio cross section. Moreover, there is the task of providing safety ejecting AGM with the exception of collision AUR and the providing of the AGM spatial stability due to their specific intrafuselage placement. Specific features of ejecting from AC compartment are intrafuselage limited space, complex aerodynamic flow of AGM arising after the opening of the valves and large extent unregulated flight AGM in a confined space deep (with flaps) AC fuselage due to undisclosed control surfaces (CS). This article analyzes the requirements for provided by intrafuselage ejection device (IFED) parameters of linear and angular motion detachable AGM. These requirements are generated using a model of aerodynamic interference AGM and AC, built on the basis of puffs model AGM in the presence of AC model. IFED discussed three types: Short-stroke (y_stroke= 0.15 m), average-stroke (y_stroke = 0.25 m) and the long-stroke (y_stroke = 0.5 m). Developed a model of the kinematics of long-stroke IFED with double acting pneumatic actuator (direct and reverse motion), and the recommendations generated by the geometric characteristics of the kinematic scheme of long-stroke IFED with the dynamic analysis of structures. Model of the dynamics of elastic IFED is developed taking into account the deformation of its rods and using the Lagrange equations of the 2nd kind. As an actuator in the IFED examines the use four-cavity double acting pneumatic and developing pull force is determined by taking into account the adiabatic process. According to the results of numerical simulations on a computer by the Runge-Kutta parameters offices AGM on various modes of the airplane, it was found that during ejection, the vertical velocity of the center of mass AGM (V_y) is monotonically increasing, overload (n_y) is practically constant, and the angular velocity (ω_z) although it varies, but with a constant sign. Estimation of parameters of ejecting AGM from AC formed by the long-stroke IFED drawn on the basis of motion simulation through AGM (comprising the steps of: moving on AGM IFED; flight AGM since its separation from the IFED to the moment of disclosure control surfaces; flight AGM after the disclosure of CS, stabilization of AGM after the disclosure of CS), showed that the trajectory of the AGM are at a safe distance from the AC in a wide range of conditions of its flight.

Keywords:

inboard ejecting device, air-launched guided missile, single stage ejecting device, long-stroke catapulting, safe breakup conditions, spatial stability, aerodynamic interference

References

1. Pravidlo M.N., Vatolin V.V. Sbornik dokladov VII Vserossiiskoi nauchno-tekhnicheskoi konferentsii «Problemy sovershenstvovaniya robototekhnicheskikh i intellektualnykh sistem LA», Moscow, 2005, pp. 73-76.
2. Artobolevskii I.I. Teoriya mashin i mekhanizmov (Theory of machines and mechanisms), Moscow, Nauka, 1975, 640 p.
3. Pravidlo M.N., Vatolin V.V., Presnyakov V.M., Tverdokhleb A.A. Aviakosmicheskaya tekhnika i tekhnologiya, 2005, no.3, pp. 10-15.