Showing papers on "Missile published in 2004"

Missile Guidance and Control Systems

Abstract: Contents 1 Introduction References 2 The Generalized Missile Equations of Motion 2.1 Coordinate Systems 2.1.1 Transformation Properties of Vectors 2.1.2 Linear Vector Functions 2.1.3 Tensors 2.1.4 Coordinate Transformations 2.2 Rigid-Body Equations of Motion 2.3 D'Alembert's Principle 2.4 Lagrange's Equations for Rotating Coordinate Systems References 3 Aerodynamic Forces and Coefficients 3.1 Aerodynamic Forces Relative to the Wind Axis System 3.2 Aerodynamic Moment Representation 3.2.1 Airframe Characteristics and Criteria 3.3 System Design and Missile Mathematical Model 3.3.1 System Design 3.3.2 The Missile Mathematical Model 3.4 The Missile Guidance System Model 3.4.1 The Missile Seeker Subsystem 3.4.2 Missile Noise Inputs 3.4.3 Radar Target Tracking Signal 3.4.4 Infrared Tracking Systems 3.5 Autopilots 3.5.1 Control Surfaces and Actuators 3.6 English Bias References 4 Tactical Missile Guidance Laws 4.1 Introduction 4.2 Tactical Guidance Intercept Techniques 4.2.1 Homing Guidance 4.2.2 Command and Other Types of Guidance 4.3 Missile Equations of Motion 4.4 Derivation of the Fundamental Guidance Equations 4.5 Proportional Navigation 4.6 Augmented Proportional Navigation 4.7 Three-Dimensional Proportional Navigation 4.8 Application of Optimal Control of Linear Feedback Systems with Quadratic Performance Criteria in Missile Guidance 4.8.1 Introduction 4.8.2 Optimal Filtering 4.8.3 Optimal Control of Linear Feedback Systems with Quadratic Performance Criteria 4.8.4 Optimal Control for Intercept Guidance 4.9 End Game References 5 Weapon Delivery Systems 5.1 Introduction 5.2 Definitions and Acronyms Used in Weapon Delivery 5.2.1 Definitions 5.2.2 Acronyms 5.3 Weapon Delivery Requirements 5.3.1 Tactics and Maneuvers 5.3.2 Aircraft Sensors 5.4 The Navigation/Weapon Delivery System 5.4.1 The Fire Control Computer 5.5 Factors In.uencing Weapon Delivery Accuracy 5.5.1 Error Sensitivities 5.5.2 Aircraft Delivery Modes 5.6 Unguided Weapons 5.6.1 Types of Weapon Delivery 5.6.2 Unguided Free-Fall Weapon Delivery 5.6.3 Release Point Computation for Unguided Bombs 5.7 The Bombing Problem 5.7.1 Conversion of Ground Plane Miss Distance into Aiming Plane Miss Distance 5.7.2 Multiple Impacts 5.7.3 Relationship Among REP, DEP, and CEP 5.8 Equations of Motion 5.9 Covariance Analysis 5.10 Three-Degree-of-Freedom Trajectory Equations and Error Analysis 5.10.1 Error Analysis 5.11 Guided Weapons 5.12 Integrated Flight Control in Weapon Delivery 5.12.1 Situational Awareness/Situation Assessment (SA/SA) 5.12.2 Weapon Delivery Targeting Systems 5.13 Air-to-Ground Attack Component 5.14 Bomb Steering 5.15 Earth Curvature 5.16 Missile Launch Envelope 5.17 Mathematical Considerations Pertaining to the Accuracy of Weapon Delivery Computations References 6 Strategic Missiles 6.1 Introduction 6.2 The Two-Body Problem 6.3 Lambert's Theorem 6.4 First-Order Motion of a Ballistic Missile 6.4.1 Application of the Newtonian Inverse-Square Field Solution to Ballistic Missile Flight 6.4.2 The Spherical Hit Equation 6.4.3 Ballistic Error Coef.cients 6.4.4 Effect of the Rotation of the Earth 6.5 The Correlated Velocity and Velocity-to-Be-Gained Concepts 6.5.1 Correlated Velocity 6.5.2 Velocity-to-Be-Gained 6.5.3 The Missile Control System 6.5.4 Control During the Atmospheric Phase 6.5.5 Guidance Techniques 6.6 Derivation of the Force Equation for Ballistic Missiles 6.6.1 Equations of Motion 6.6.2 Missile Dynamics 6.7 Atmospheric Reentry 6.8 Missile Flight Model 6.9 Ballistic Missile Intercept 6.9.1 Introduction 6.9.2 Missile Tracking Equations of Motion References 7 Cruise Missiles 7.1 Introduction 7.2 System Description<7.2.1 System Functional Operation and Requirements 7.2.2 Missile Navigation System Description 7.3 Cruise Missile Navigation System Error Analysis 7.3.1 Navigation Coordinate System 7.4 Terrain Contour Matching (TERCOM) 7.4.1 Introduction 7.4.2 De.nitions 7.4.3 The Terrain-Contour Matching (TERCOM) Concept 7.4.4 Data Correlation Techniques 7.4.5 Terrain Roughness Characteristics 7.4.6 TERCOM System Error Sources 7.4.7 TERCOM Position Updating 7.5 The NAVSTAR/GPS Navigation System 7.5.1 GPS/INS Integration References A Fundamental Constants B Glossary of Terms C List of Acronyms D The Standard Atmospheric Model References E Missile Classi.cation F Past and Present Tactical/Strategic Missile Systems F.1 Historical Background F.2 Unpowered Precision-Guided Munitions (PGM) References G Properties of Conics G.1 Preliminaries G.2 General Conic Trajectories References H Radar Frequency Bands I Selected Conversion Factors Index

Integrated guidance and control for homing missiles

Abstract: he need to engage and negate highly maneuverable threats imposes stringent performance requirements on missile interceptors. The design challenges are significant and require advances in interceptor airframe, sensor and propulsion systems, and guidance and control (G&C) algorithms. In essence, the G&C algorithms must orchestrate the various interceptor components to maximize lethality across the threat space. To this end, traditional G&C designs use a decoupled architecture involving three discrete algorithms. Separate designs and weak functional interactions among the algorithms make interceptor performance optimization difficult. In this article, we introduce an alternate G&C architecture wherein the traditional elements are replaced by a single component that performs all three functions. This integrated G&C (IGC) paradigm facilitates a level of synergism between flight control and guidance functions that is difficult to emulate within a decoupled framework. Moreover, the IGC design process unifies interceptor performance optimization versus the decoupled approach. Using a six-degree-of-freedom simulation tool, we compare a prototype IGC algorithm to a benchmark G&C system using a decoupled structure. We show that the IGC concept significantly improves the mean and standard deviation of the final miss distance against stressing threats.

Adaptive, Integrated Guidance and Control for Missile Interceptors

Abstract: This paper presents an adaptive, integrated guidance and control approach for ballisticmissile interceptors using backstepping control techniques. The primary benefits of backstepping are that control loops are derived in a rigorous and systematic manner, and unmatched uncertainties in the plant dynamics are handled readily. An on-line neural network is used to provide robustness to parametric uncertainties in the missile aerodynamics. The adaptive integrated approach enables shorter design times, and more ecient designs, by removing the need for an iterative integration process required by traditional methods. The algorithm development is restricted to the pitch-plane, but can be readily extended to all three axes. Numerical simulation results, including Monte-Carlo results, are presented from a high-fidelity, nonlinear simulation to demonstrate the ecacy of the approach.

Compensation of actuator dynamics in nonlinear missile control

Abstract: This brief presents an approach to the compensation of the actuator dynamics in nonlinear missile control. In general, actuator dynamics are not considered in nonlinear missile control systems. Here, we analyzed the influences of actuator dynamics on the nonlinear missile controller and found that the second-order actuator dynamics showed risks of potentially destabilizing the overall system. Thus, to accommodate for the influence of the actuator dynamics, a compensator is proposed where the information of the nonlinear control input and the actual fin deflection is incorporated. We also conducted performance and stability analysis for the proposed control system, including actuator dynamics. We were able to confirm the validity of the proposed approach based on simulation results for the first- and second-order actuator dynamics.

Development of an integrated fuzzy-logic-based missile guidance law against high speed target

Abstract: How to develop a novel missile guidance law that can act effectively against very high speed incoming targets, such as ballistic missiles, has been a major concern in the defense technique. It has been unveiled recently in the literature that the most effective way for a lower speed interceptor to successfully engage an incoming target with very high speed is to limit the aspect angle between the missile and target flight path to within 180/spl deg/ plus or minus few degrees. On the basis of this requirement, a new integrated fuzzy guidance law is developed in this paper against very high-speed maneuverable targets on three-dimensional space. An integrated fuzzy type guidance law is explored for midcourse and terminal phases. It is shown that the integrated guidance scheme offers excellent tracking performance as well as performance sensitivity with respect to some parametric variations.

Closed-Loop Missile Yaw Control via Manipulation of Forebody Flow Asymmetrics

Abstract: A high-alpha, closed-loop flow-control system for missile yaw stabilization and enhanced maneuverability was designed, developed, and successfully demonstrated in a series of open- and closed-loop experiments on a fin-less 3:1 caliber tangent ogive missile model. The active flow-control-based yaw control system consisted of eight fastresponse pressure sensors and eight deployable flow effectors arranged in concentric rings on the missile nose cone. The devices were integrated with a closed-loop controller that modulated the effectors to manipulate flow asymmetry around the missile forebody. Side forces caused by crossflow separation and forebody flow asymmetries were observed on the missile model between 40 and 60 deg alpha. Parametric studies showed that actuating flow effectors in certain configurations resulted in cancellation of large side forces associated with the natural flow asymmetry under both steady and unsteady flow conditions. Exploratory studies conducted on optimized flow effector configurations resulted in control maps with wide spectrum of positive and negative side forces for yaw modulation. Dynamic experiments successfully demonstrated the ability of the closed-loop control system to generate and maintain a range of desired yawing moments during high-alpha pitch sweeps.

Head Pursuit Guidance for Hypervelocity Interception

Abstract: *† A new guidance law for intercepting targets in a novel head-pursuit engagement is presented. The guidance law positions the interceptor missile ahead of the target, on its flight trajectory, so that both fly in the same direction. The missile speed is planned to be lower than that of the target, and therefore the target closes in on the interceptor missile. Using this approach the closing speed is significantly reduced relative to a head-on engagement; compared to a tail-chase engagement, the low closing speed is achieved with reduced energy requirements. The guidance law is similar to deviated pure pursuit but with a time varying lead angle. Analytic solutions of the relative trajectories and interception envelopes are given for the case of a non-maneuvering target. The performance of the new guidance law is studied through simulation for the case of a maneuvering target and interceptor employing a continuous or bang-bang maneuver device. The implementation of the new guidance scheme may dramatically reduce the requirements from missile subsystems for the interception of high speed targets, such as ballistic missiles.

Fiber laser based directional infrared countermeasure (DIRCM) system

Abstract: A DIRCM (Direct IR Counter Measures) system is described that includes a detection and warning means for detecting a missile that might pose a threat on the platform to which said system is allocated, and generating a warning of its existence. The warning may include data that enable the calculation of the expected direction from which the missile is approaching. The DIRCM system may also include acquisition means for performing acquisition of the approaching missile in accordance with the data provided by the detection and warning means, and issuing data that may enable the calculation in real time of the updated position of the missile, a fiber laser means for generating a laser beam, and a motion and aiming enabled turret means, coupled with the laser means, for directing the laser beam unto the approaching missile. The laser beam may be generated in accordance with the missile's updated position as calculated based on the data received from the acquisition means, and processing means, linked to the detection and warning means, and also to the acquisition means, the laser means and the turret means.

Externally cued aircraft warning and defense

Abstract: Methods, computer-readable media, and systems for externally cued aircraft warning and defense are disclosed. A surveillance system (110) may include a sensor field or array (114) and may include a processor system (116) that processes signals including acoustic signals received by the sensor array. Signals including acoustic signals are processed to determine the presence of indicia, including acoustic signatures, of known surface-to-air missiles (130) including man-portable air defense systems. When the presence of such surface-to-air missiles is indicated, a cue signal is sent to one or more countermeasure systems (144, 146, 150) that include one or more countermeasures such as chaff, expendable decoys and flares. The countermeasure systems may be ground-based or aircraft-based. The countermeasures are deployed in response to the cue signal. The surface-to-air missile may consequently be defeated.

Ramjet Powered Missile Design Using a Genetic Algorithm

Abstract: A methodology for developing optimized designs for symmetric - centerbody ramjet powered missiles, using genetic algorithms as the central driver for the system optimization process, has been developed. This paper contains discussion of that methodology and shows results for a typical design scenario.

Space Weapons: Crossing the U.S. Rubicon

Abstract: In the next decade, planned U.S. military activities in outer space will cross several important thresholds. By 2008 the U.S. Missile Defense Agency intends to deploy a test bed of space-based kinetic-energy kill vehicles (KKVs) to destroy high-speed collision test targets that mimic nuclear-armed reentry vehicles in the midcourse of their arc through space. In early 2006 a Missile Defense Agency satellite experiment, NFIRE, is planned to attempt to intercept a rocket in or near boost phase. Beyond missile defense, these U.S. space-deployed weapons will have broad implications for the entire space sector. Because a KKV designed to intercept missiles could also function as an antisatellite weapon (ASAT) and as a means to deny other countries' access to space, U.S. adversaries might feel compelled to develop means to counter these and other U.S. space weapons with their own systems based in space or on the ground. In light of these impending developments, this article examines the possible roles for space weapons in addition to missile defense-for protecting satellites, controlling space, and projecting force-in terms of capabilities and cost.1 Our analysis is intended to help policymakers in the executive and legislative branches to make more fully informed decisions about missile defense and related near-term U.S. military activities in space, taking into account implica-

Tunable H robust guidance law for homing missiles

Abstract: The proposed robust guidance control law can attain satisfactory robust performance for pursuing an unpredictable maneuvering target. Sufficient condition analysis is also carried out for the proposed guidance control law with tunable parameters. The proposed method not only need not touch the hard-solved Hamilton–Jacobi partial differential inequality but also guarantees that the line-of-sight distance between homing missile and maneuvering target can quickly converge to zero. A previously-implemented simulation discussed elsewhere is performed using the guidance control law to illustrate the efficiency of the proposed design.

Airborne Boost-Phase Ballistic Missile Defense

Abstract: Boost-phase ballistic missile defense is alluring because rocket boosters are easy to detect and track, they are relatively vulnerable due to the large axial loads on a missile under powered flight, the entire payload (single or multiple warheads and midcourse penetration aids) may be destroyed in a single shot, and countermeasures to defeat boost-phase defense are more difficult to devise than for midcourse ballistic missile defenses. Moreover, if intercepted several seconds before booster burnout, the debris will land well short of the target area, although collateral damage to other territory is a serious concern. On the other hand, boost-phase ballistic missile defense is technically challenging because the intercept timelines are very short (1–3 minutes for theater-range ballistic missiles and 3–5 minutes for intercontinental range missiles) and missile boosters are accelerating targets, thus complicating the design of homing kinetic-kill vehicles (KKVs). This article examines the technical feasibili...

Variable structure-based nonlinear missile guidance/autopilot design with highly maneuverable actuators

Abstract: In this brief, we propose a variable structure based nonlinear missile guidance/autopilot system with highly maneuverable actuators, mainly consisting of thrust vector control and divert control system, for the task of intercepting of a theater ballistic missile. The aim of the present work is to achieve bounded target interception under the mentioned 5 degree-of-freedom (DOF) control such that the distance between the missile and the target will enter the range of triggering the missile's explosion. First, a 3-DOF sliding-mode guidance law of the missile considering external disturbances and zero-effort-miss (ZEM) is designed to minimize the distance between the center of the missile and that of the target. Next, a quaternion-based sliding-mode attitude controller is developed to track the attitude command while coping with variation of missile's inertia and uncertain aerodynamic force/wind gusts. The stability of the overall system and ZEM-phase convergence are analyzed thoroughly via Lyapunov stability theory. Extensive simulation results are obtained to validate the effectiveness of the proposed integrated guidance/autopilot system by use of the 5-DOF inputs.

Multicriteria Design Optimization of a Supersonic Inlet Based upon Global Missile Performance

Abstract: The flight performance of a ramjet-powered missile is improved through the use of an automated optimization loop relying on computational-fluid-dynamics tools. A generic supersonic airbreathing missile is first described,and its performance is assessed for a representative mission using Reynolds-averaged Navier-Stokes computations for aerodynamics prediction and theoretical engine performance models. The loop links together an optimization algorithm with an aerodynamic software computing the aerodynamic balance of the missile. Several optimizations are performed using different global algorithms such as simplex, evolutionary strategies, or genetic algorithms. The first ones are mono-objective: for each point of the mission (acceleration, cruise, and maneuver), the best inlet shape has to be found. Then multiobjective optimizations are performed in order to find the pareto front, that is, the best set of shapes satisfying the whole mission.

Numerical Simulation of Rolling Airframes Using a Multilevel Cartesian Method

Abstract: A supersonic rolling missile with two synchronous canard control surfaces is analyzed using an automated, inviscid, Cartesian method. Sequential-static and time-dependent dynamic simulations of the complete motion are computed for canard dither schedules for level flight, pitch, and yaw maneuvers. The dynamic simulations are compared directly against both high-resolution viscous simulations and relevant experimental data and are also utilized to compute dynamic stability derivatives. The results show that both the body roll rate and canard dither motion influence the roll-averaged forces and moments on the body. At the relatively low roll rates analyzed in the current work these dynamic effects are modest; however, the dynamic computations are effective in predicting the dynamic stability derivatives, which can be significant for highly maneuverable missiles.

Electromagnetic missile launcher

Abstract: A technique for launching a missile that avoids some of the costs and disadvantages for doing so in the prior art. In particular, the illustrative embodiment of the present invention uses an electromagnetic catapult to throw the missile clear of the launch platform—with sufficient velocity to attain aerodynamic flight—before the missile's engine is ignited.

System and method for the defense of aircraft against missile attack

Abstract: A CM system for the defense of aircraft against missile attack leverages nanocrystal technology to provide safe and reliable protection. The CM system generally includes one or more ground-based laser emitter subsystems, one or more ground-based Doppler-sensitive radar subsystems, an aircraft-based nanocrystal dispenser subsystem, and an engagement control subsystem that governs the operation of the CM system. In response to the detection of a missile within an attack envelope, the engagement control subsystem instructs the dispenser subsystem to release nanocrystals into an area proximate the aircraft. In addition, the engagement control subsystem instructs one or more of the laser emitter subsystems to direct an excitation signal at the dispensed nanocrystal “cloud” to thereby cause the nanocrystals to emit infrared radiation that approximates that of jet engine exhaust. The properties of the nanocrystals and the excitation signal are selected to ensure that the emitted radiation provides an effective decoy for the missile seeker system.

Nonlinear Aeroelastic Analysis of a Deployable Missile Control Fin

Abstract: The nonlinear aeroelastic characteristics of a deployable missile control fin have been investigated. Modes from free vibration analysis and a doublet-point method are used for the computation of supersonic unsteady aerodynamic forces. The minimum-state approximation is used to approximate the aerodynamic forces. The fictitious mass modal approach is applied to reduce the problem size and the computation time in the linear and nonlinear flutter analyses. For the nonlinear flutter analysis, the deployable hinge is represented by an asymmetric bilinear spring and is linearized using the dual-input describing function method. From the nonlinear flutter analysis, three different types of limit-cycle oscillations are observed in the wide range of airspeed over the linear flutter boundary. The aeroelastic characteristics of the missile control fin can become more stable due to the existence of the deployable hinge nonlinearity.

System and method for launching a missile from a flying aircraft

Abstract: System for launching a missile from a launch region within the atmosphere of a planet, the missile being located within a flying vehicle before launching the missile, the system including a missile support coupled with the missile, and a foldable control-surface mechanism coupled with the missile support, the foldable control-surface mechanism being in a folded position before ejecting the missile support and the missile from the flying vehicle, the foldable control-surface mechanism moving from a folded position to an operational position after ejecting the missile support and the missile from the flying vehicle, wherein the foldable control-surface mechanism maneuvers the missile and the missile support to a predetermined orientation suitable for launching the missile, wherein the missile support is decoupled from the missile when the missile and the missile support are at the predetermined orientation, and wherein the missile is launched after reaching the predetermined orientation.

Multi-mission payload system

Abstract: A missile (10), such as a cruise missile, has a nose payload portion (20) having a frangible nose cover (44) and a relatively hard target penetration nose cone (48). The nose cone may have a liquid fuel tank (32) within, and a chemical energy explosive charge (26), such as a shaped charge (28), aft of the liquid fuel tank. The target penetration nose cone enables perforation of certain types of targets prior to detonation of the chemical energy explosive and the liquid fuel. The frangible nose cover is configured to be easily perforated or otherwise removed by the explosive force of the chemical energy explosive charge when the missile system is utilized for the attack of hard targets. The nose payload portion may have a fragmentation case (54), with one or more features designed to enhance fragmentation during detonation of the explosive and/or the liquid fuel.

Progress in the development of a computational model for the army's impinging stream vortex engine

Abstract: The Army is developing gelled bipropellants and tactical missile propulsion systems that utilize these propellants for both current and future combat systems. The use of hypergolic gel propellants introduces new challenges in combustion control. One of these challenges is the mixing of oxidizer and fuel to obtain maximum performance from the combustor without increasing the size of the engine. The Army’s impinging stream vortex engine, ISVE, offers an alternative to increasing the volume of the combustion chamber and has already generated excellent performance test data. Since the ISVE is a new concept, analytical models that relate engine performance to engine design parameters are just beginning to emerge. In order to fully exploit the performance advantages that have been realized for the ISVE, it is desirable to understand the underlying flow physics of the engine. This paper describes the Army’s effort to use multidimensional, multiphase computational fluid dynamics, combined with highperformance computers to generate simulations of the ISVE that reveal gas/droplet dynamics and combustion patterns as well as predict chamber pressure and thrust levels for the engine. The goal is to utilize this computational tool to optimize the ISVE performance for a host of strategic Army missions.

Air-based vertical launch ballistic missile defense

Abstract: An air-based vertical launch system is described by means of which ballistic missile defense can be achieved effectively from a large aircraft. A method for ensuring safe missile egress is proposed. A method for ensuring that the missile strikes the ballistic missile payload section is also proposed. Together, the air basing method employing vertical (or near-vertical) launch and semi-active laser guidance yield an affordable and operationally effective missile defense against both tactical and long-range ballistic missiles. The affordability of missile defense is enhanced by the ability of an aircraft equipped with a vertical launcher to simultaneously carry out several defensive and offensive missions and to provide other capabilities such as satellite launch at other times. Methods for employing an aircraft equipped with a vertical (or near-vertical launcher) and one or more of the proposed egress assurance mechanisms in offensive ground attack missions, mine laying, and satellite launch missions are also proposed.

China's Cruise Missile Program

Abstract: DURING OPERATIONS Desert Shield and Desert Storm, the U.S. Navy launched 288 Tomahawk land-attack cruise missiles. Eighty percent hit their targets. (1) The Tomahawk is so accurate that after a 1,600-kilometer (km) journey, its 454-kilogram (kg) warhead usually impacts within 3 meters of the aim point. (2) The People's Republic of China took note of the magnificent performance of these weapons and focused its efforts on acquiring cruise missiles. During the 1991 Persian Gulf war, China also learned that the United States is too powerful to be challenged directly by military means. Having a stockpile of cruise missiles would enable China to influence U.S. decisions without becoming involved in a major conflict. Cruise missiles would offer China a precision-strike capability at a much lower cost than developing and training a modern air force would. Missiles require less maintenance than a fleet of modern jet aircraft; are suitable against land- and sea-based targets; are relatively cheap and reliable; and have few vulnerable parts. (3) Cruise missiles also do not entail political risks because, unlike disgruntled pilots, they cannot defect. (4) China's effort to acquire cruise missiles is a disturbing development. Robert Walpole, a national intelligence officer for strategic and nuclear programs, testified before Congress that "[w]e may not be able to provide much, if any, warning of a forward based ballistic missile or land-attack cruise missile threat to the United States. Moreover, land-attack cruise missile development can draw upon dual-use technologies." (5) Missile Acquisition Technologies available on the commercial market have eliminated many of the barriers to cruise-missile proliferation, and many components used in cruise missiles are common to commercial aircraft. Companies manufacture cruise missile airframes using the same technologies as for manufacturing light aircraft. A country like China, which can build manned aircraft, can easily produce cruise missiles. China is also acquiring these systems by direct purchase and indigenous development. Direct purchase. The best option for acquiring missiles is to procure the entire cruise missile system directly from another country. The National Air Intelligence Center (NAIC) estimates that by the end of the decade, at least nine countries will be capable of producing land-attack cruise missiles. (6) Many such countries will offer their cruise missiles for export in order to maintain their military industrial complex because their nation's defense budgets are in decline. This rapid increase in the number of cruise-missile suppliers means that China will find itself seeking cruise missiles during a "buyer's market." Purchased missiles will give China an immediate precision-strike capability and the opportunity to use a proven system. Since the 1989 Tiananmen Square incident and the curtailment of U.S. foreign military sales to China, China has turned to Russia to acquire most of its current weapons systems and has cloaked its military development in secrecy. China's People's Liberation Army (PLA) subscribes to Deng Xiaoping's strategy of hiding capabilities to maximize options for the future. (7) It is difficult, therefore, to assess the full extent of China's cruise missile acquisition program. However, the open literature suggests that China has purchased the Russian Kh-41 Moskit supersonic, sea-skimming, anti-ship cruise missile (ASCM). As an air-launched ASCM, the Kh-41 Moskit has a range of 250 kilometers, can attack ships at speeds greater than Mach 2, carries a 200-kg payload, and can make 10-G turns to defeat a ship's defensive capabilities. (8) The Kh-41 can "defeat U.S. Navy Aegis ship defense systems and destroyers," which is daunting because the U.S. and Japan expect the Aegis to play a key role in any future Japanese or U.S. theater missile defense system. (9) New Su-27 fighters and Su-30 long-range interceptors equipped with Kh-41s give China the capability to sink U. …