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Lecture 2 Missile & Rocket School of Astronautics Slide 2 4 1 2 3 Principles of Atmospheric Flight Basic Concepts of Missile & Rocket Missile & Rocket Propulsion 5 Missile Classification & Weapon System Organization Principle & Composition of Launch Rocket Slide 3 1.Basic Concepts of Missile & Rocket What is a missile? Missile is a weapon that has warhead, flies with own propulsion system, and its flight path is controlled & guided by control system. What is a rocket? Rocket is a vehicle that relies on the reaction of rocket motor exhaust gas to fly. Qian Xuesen Wernher von Braun Slide 4 Differences: Missile vs. Rocket Motor Rocket: rocket motor Missile: rocket motor, or jet engine, or combined engine, etc. Payload Missile: warhead Rocket: warhead (only when used as weapon) Guidance system Missile: must have Rocket: free or guided rocket DF-5Strategic Missile CZ-2F Launch Rocket Slide 5 1 Common classification(can vary depending on criteria) Usage strategic, tactic Range short-, medium-, long-range, intercontinental Guidance system commanded, homing, inertia, combined Trajectory Cruise, ballistic, combined Launch area & target area surface-surface, surface-air, air-surface, air-air Target character air defence, anti-tank, anti-radiation, anti-ship, anti-missile, anti-satellite Javelin Scud Tomahawk Sidewinder Tactic, air-air, homing Tactic, surface-surface, anti-tank Ballistic, short-range, surface-surface Cruise, tactic, combined guidance 2.Missile Classification & System Organization Slide 6 Anti-ship Missile: launched from ship, shore, or aircraft to attack surface vessels Warhead: Semi armor piercing explosive Propulsion: solid rocket motor Self guidance, auto-pilot When enters target area, seeker automatic searches, captures, & attacks target Frequently used in modern naval battles On June 12,1982, during Falklands War, a shore- based Exocet (MM-38) anti-ship missile launched by Argentina army hit HMS Glamorgan missile destroyer. Later an Argentina airborne Exocet (AM- 39) sank HMS Sheffield missile destroyer US Harpoon anti-ship missile French Exocet anti-ship missile 2 Examples Slide 7 Surface-Air Missile (SAM): ground launch and attack airborne targes, also called air-defence missile.Core of SAM weapon system Compared to anti-aircraft gun, longer range, higher ceiling, higher single shot kill probability Compared to intercept aircraft, faster response, higher, higher fire power, unlimited by target speed & altitude Example 4 th Middle East war, SA-6 shot down a number of Israel fighters, gained air superiority during early battle. SA-6 air defence missile Patriot air defence missile 2 Examples Slide 8 Slide 9 Air-to-air missile: missiles that launched by flight vehicles to attack airborne targets. Main weapon: fighters Dogfight weapon: fighter bomer, attack aircraft, helicopter self defence weapon (theoretically): refueling aircraft & airborne early warning (AEW) Components: guidance system, warhead, fuse, propulsion system, airframe,& surfaces AA missile weapon system: missile, onboard fire control, launch, & testing systems US AIM-120 medium Air-to-air missile Israel Python-5 Air-to-air missile 2 Examples Slide 10 Anti-tank Missile: missiles used to destroy tank and other armored target Mid-1950s, led by France, later followed by many nations. Three generations: becoming the most effective anti-tank weapon Components: warhead, propulsion, onboard guidance system,& airframe Warhead: hollow charge armor piercing US TOW anti-tank missile Russia Cornet anti-tank missile 2 Examples Slide 11 3 Missile Weapon System A general term of missiles & its supporting equipments and facilities, including Missile is the center of the three systems Missile Weapon System Missile System Fire Control System Tech. Support System Airframe Propulsion Guidance Fuse-Warhead Electrics Target Detection & Display Data Processing & Computing Launch Platform Data Measuring & Processing Launch Device Testing Equipments Vehicles Power Supply Slide 12 1 Missile System 5 subsystems: airframe, propulsion, guidance. Fuse-warhead, & electrics/power fly under the action of guidance system & propulsion system, being guided to the target, fuse detonates warhead to destroy it. 3 Missile Weapon System Brahmos supersonic anti-ship missile Slide 13 Missile structure Slide 14 2 Fire Control System Full name: fire command & control, general term for equipments that control weapon and automatic aim and launch Components 1.Target tracker 2.Fire data computer 3.System console 4.Fire controller 5.Interfaces 6.Peripheral equipment Aegis combat system Slide 15 3 Tech. Support Equipments Performing missile lifting, transportation, storage, maintenance, test, power supply, & technical preparation Ensure missile is under good technical condition & combat ready Including: test instrument, crane, tech prep ground, storage trailer, power supply vehicle, communication & command vehicle, & other supporting tools Slide 16 Example: Air-defense Missile Weapon System Example: Land-Based Midcourse Anti-Missile System Slide 17 Mission: choose best time to destroy/damage targets, kill, fighting forces Effective load of Missile. It distinguishes missile as a weapon from other flight vehicles Components Warhead destroy targets Fuse: detonate warhead timely Safety Devices Ensure warhead safety during missile maintenance Ensure fuse detonates warhead reliably Fuse-Warhead System 4 Fuse-Warhead System Slide 18 Conventional Charge Nuclear Warhead Special Warhead Warhead Blast Warhead Shaped Charge Penetration warhead Fragmentation Warhead Atomic Bomb Hydrogen Bomb neutron bomb Laser Warhead X-Ray Warhead Chemical Warhead Combustion Warhead Smoking or Luminous Warhead Fuse-Warhead System 4 Fuse-Warhead System Slide 19 Major Configurations of Warhead Slide 20 Fusing System Determining detonation timing & detonate warhead Classification non-contact fuse for airborne targets, such as aircraft & missile, which are small & highly maneuverable. contact fuse commonly used by missiles with blast warhead & shaped charge penetration warhead. Slide 21 3. Principles of Atmospheric Flight Whats Mach number Speed of Sound: speed of acoustic wave propagated in the medium. 341m/s in the air Mach number: the ratio of speed at a point in the field, V, to the speed of sound, a, i.e., Ma=V/a It reflects effects of compressibility to low. Compressibility cant be ignored when Ma0.3 (1)Basic Aerodynamics Subsonic Ma that of free-stream reaction force (i.e., thrust) Propellant Solid Propellant Ramjet Engine Integral Rocket Ramjet Engine Ducted rocket engine Booster Nozzle Slide 59 Characters of Ramjet Utilizes oxygen in the air as oxidizer, has unique advantage in high speed long range flights. 1 Advantages more economical than turbojet engine in supersonic flights no internal rotating parts, resulting in simple structure, light weight, low cost, high thrust weight ratio unlimited by rotating part temperature capability, more heat can been added to combustor 2 Disadvantages Can not self start, depends on booster to accelerate to certain speed Lower thrust per frontal area Sensitive to flight condition change, inlet & nozzle need to be adjusted to work in wide Mach number range Slide 60 Ramjet Turbo Ramjet = Turbojet + Ramjet Scramjet Wave Rider Slide 61 Launch Vehicle a type of space transportation vehicle used to send satellite, spaceship, space station, or space probes into predefined orbit. 1 st cosmic velocity 7.9Km/s, circular motion around the Earth 2 nd cosmic velocity 11.2Km/s. escape velocity. >11.2Km/s will fly out of the Earth, interplanetary flight 3 rd cosmic velocity 16.6Km/s: fly out of solar system 6.Composiiton & Principles of Launch Vehicle Historically, scientists have been studying the problem of escaping from Earth gravity for many years, e.g. Newtons cannon ball. Based on these, one get cosmic velocities. Slide 62 Tsiolkovsky Formula: calculate rocket velocity increase during engine runningalculate rocket velocity increase during engine running Tsiolkovsky Formula "formula of aviation" Tsiolkovsky Formula "formula of aviation" Russian Proton Launch Vehicle V:incremental speed W: relative velocity of backward exhaust jet of engine m 0 : launch mass (including propellant) m k : burnout mass m 0 / m k : mass ratio Assumptions: ignore aerodynamics & gravity of Earth Slide 63 Engine jet velocity 3km/s; To reach 1 st cosmic velocity 7.9km/s What is the mass ratio mass ratio 10, i.e., at launch propellant mass is 90% of total mass! if so, single stage rocket was unable to reach 1 st cosmic velocity 2 approaches to increase V, increasing W & m 0 / m k, Before new propellant developed, increasing mass ratio is the only feasible way. At given m 0, reduce m k, could increase mass ratio, i.e., jettisoning excess m k, that is the ideal of modern multi-stage rocket. Tsiolkovsky imagined rocket & spaceship Tsiolkovsky Formula Slide 64 Multi-Stage Rocket Staging Scheme Based on attachment method of every stage, there are 3 schemes Serial/tandem design a stage on top of another Parallel design: every stage attached alongside each other Mixed design: both serial & parallel staging are used Serial---CZ-3A Parallel--- Energia Mixed---CZ-2F Slide 65 Composition of Launch Vehicle System Launch Vehicle Payload Electric System Control System Structure System Propulsion System Launch Vehicle: space transportation vehicle composed of multi-stage rockets. It sends satellite, manned spaceship, space station, space probe into orbit. It has such components: Slide 66 Composition of Launch Vehicle System CZ-3C 1. Dome 2. Payload 3. Payload Adapter 4. Instrument Bay 5. LH2 Tank 6. LOX Tank 7. Inter-stage Section 8. 3 rd Stage Engine 9. Oxidizer Tank 10. Inter-tank Section 11. Fuel Tank 12. 2 nd Stage V ernier Engine 13. 2 nd Stage Engine 14. Inter stage truss 15. Oxidizer Tank 16. Fuel Tank 17. 1 st Stage Engine 18. Booster Nosecone 19. Booster Oxidizer Tank 20. Booster Fuel Tank 21. Booster Engine Slide 67 Rocket Flight Control System (FCS) To ensure spacecraft enter correct orbit, launch vehicles must strictly follow designed trajectories. The predefined trajectory is called Standard Trajectory. Rocket control has 3 functions: Identify average deviation between actual trajectory and standard trajectory Sending control command based on deviation Correcting actual trajectory into standard trajectory Launch Vehicle Control System Flight Control System (Onboard) Testing / Launch Control System (Ground) Guidance & Control System Attitude Control System Power Supply & Timing Control System Auto. Launch Control System Monitoring & Control System Power Supply System Auto. Testing System Slide 68 Multi-Stage Rocket Trajectory Launch Trajectory: from ground liftoff to send payload to operating orbit Divided into several segments vertical liftoff Programmed turning Sub-stage separation Transition flight(free flight) Dome jettison Into orbit Reentry recoverable spacecraft Slide 69 Liftoff Programmed Turning Secondary Booster Separation Main Booster Separation Dome Jettison 1 st Stage Separation, 2 nd Stage Start 2 nd Stage Main Power Flight 2 nd Stage power off, start coasting 2 nd Stage Secondary Start 2 nd Stage Secondary Power off Satellite Rocket Separation Multi-Stage Rocket Trajectory Slide 70 1.CZ-2F Blast off 2.Jettison of escape tower 3.Jettison of dome 4.Spaceship-Rocket separation 5.Tracking Tiangong-1 6.Rendezvous and docking 7.Spaceship-Space station separation 8.Orbital module & re-entry module separation 9.re-entry module & power module separation 10.re-entry module reenter atmosphere 11.Parachute landing 12.Landed & recover 2. Shenzhou-9 Launch Shenzhou-9 Launch Animation Slide 71