Authors: Robert L. McCoy
ISBN-13: 9780764307201, ISBN-10: 0764307207
Format: Hardcover
Publisher: Schiffer Publishing, Ltd.
Date Published: January 1999
Edition: (Non-applicable)
Modern Exterior Ballistics is a comprehensive text covering the basic free flight dynamics of symmetric projectiles. The book provides a historical perspective of early developments in the 19th century, the technology leading to World War I and that through World War II into the modern post-war era. Historical topics include the first ballistic firing tables, early wind tunnel experiments, the development of free flight spark ranges and the first supercomputer, ENIAC, which was designed to compute artillery trajectories for the U.S. Army Ballistic Research Laboratory. The level of the text requires an undergraduate education in mathematics, physics, and mechanical or aerospace engineering. The basic principles of ballistic science are developed from a comprehensive definition of the aerodynamic forces that control the flight dynamics of symmetric projectiles. The author carefully starts with the basic vacuum point mass trajectory, adds the effects of drag, discusses the action of winds, simple flat fire approximations, Coriolis effects and concludes with the classic modified point mass trajectories. Included in the discussion are analytical methods, change of variables from time to distance, numerical solutions and a chapter on the Siacci Method. The Siacci Method provides a historical perspective for computing flat fire trajectories by simple quadrature and is used in the sporting arms industy. The final six chapters of the book present an extensive physical and mathematical analysis of the motion of symmetric projectiles. The linearized equations of angular and swerving motion are derived in detail. The effects of mass asymmetry, in-bore yaw, cross wind and launch in a slipstream arediscussed. Special consideration is given to the derivation and explanation of aerodynamic jump. These subjects are then expanded to include a complete chapter on nonlinear aerodynamic forces and moments. The final chapter in the book presents an overview of experimental methods for measuring the flight dynamics of projectiles. The great forte of Modern Exterior Ballistics is the author's effort to provide many fine specific examples of projectile motion illustrating key flight behaviors. The extensive collection of data on projectiles from small arms to artillery used to substantiate calculations and examples is alone a valuable reference. The ultimate joy of the book is the incomparable comprehensive set of flow field shadow graphs illustrating the entire spectrum of projectile flight from subsonic, through transonic and supersonic. The volume is a necessary addition to any undergraduate or graduate course in flight dynamics.
This text covers the basic free flight dynamics of symmetric projectiles. It provides a historical perspective of early developments in the 19th century, the technology leading to World War I and that through World War II into the modern post-war era. Historical topics include the first ballistic firing tables, early wind tunnel experiments, and the development of free flight spark ranges. McCoy, who was an aerospace engineer at the U.S. Army Ballistic Research Laboratory, provides many specific examples of projectile motion illustrating key flight behaviors. In addition, he presents flow field shadow graphs illustrating the entire spectrum of projectile flight from subsonic through transonic and supersonic. Annotation c. Book News, Inc., Portland, OR (booknews.com)
Preface | 9 | |
Chapter 1 | A Brief History of Exterior Ballistics | 10 |
1.1 | Introduction | 10 |
1.2 | Early Beginnings | 10 |
1.3 | Exterior Ballistics in the Nineteenth Century | 10 |
1.4 | Early Twentieth Century Developments | 13 |
1.5 | The First Modern Aerodynamic Force-Moment System for Projectiles | 17 |
1.6 | The Beginnings of Computational Aerodynamics | 17 |
1.7 | Exterior Ballistics Research During the Second World War | 18 |
1.8 | Post-War Progress in Exterior Ballistics | 28 |
1.9 | Future Developments | 29 |
Chapter 2 | Aerodynamic Forces and Moments Acting on Projectiles | 32 |
2.1 | Introduction | 32 |
2.2 | Drag Force | 33 |
2.3 | Spin Damping Moment | 33 |
2.4 | Rolling Moment for Canted Fin Projectiles | 34 |
2.5 | Lift and Normal Forces | 34 |
2.6 | Overturning Moment | 36 |
2.7 | Magnus Force | 36 |
2.8 | Magnus Moment | 37 |
2.9 | Centers of Pressure of the Normal Force and the Magnus Force | 37 |
2.10 | Pitch Damping Force | 38 |
2.11 | Pitch Damping Moment | 38 |
2.12 | Neglected Forces and Moments | 39 |
2.13 | The Effect of Center of Gravity Location on the Aerodynamic Forces and Moments | 39 |
2.14 | Modern Aeroballistic and Older Ballistic Nomenclatures | 40 |
2.15 | Summary | 40 |
Chapter 3 | The Vacuum Trajectory | 42 |
3.1 | Introduction | 42 |
3.2 | Equations of Motion | 42 |
3.3 | Discussion of the Vacuum Trajectory | 44 |
3.4 | Firing Uphill and Downhill | 47 |
3.5 | Summary | 51 |
Chapter 4 | Notes on Aerodynamic Drag | 52 |
4.1 | Introduction | 52 |
4.2 | Classical Drag Measurements | 52 |
4.3 | The Physical Nature of Drag | 55 |
4.4 | Airflow Regimes | 55 |
4.5 | The Effect of Projectile Shape on Drag | 70 |
4.6 | The Effect of a Burning Tracer on Drag | 73 |
4.7 | The Effect of Fins on the Drag | 74 |
4.8 | The Drag of Smooth Spheres | 76 |
4.9 | The Effect of Yaw on Drag | 78 |
4.10 | Minimum Drag Projectile Shapes | 80 |
4.11 | Summary | 84 |
Chapter 5 | The Flat-Fire Point Mass Trajectory | 88 |
5.1 | Introduction | 88 |
5.2 | Equations of Motion | 89 |
5.3 | The Flat-Fire Approximation | 90 |
5.4 | Special Analytical Solutions of the Flat-Fire Equations | 91 |
5.5 | Constant Drag Coefficient | 92 |
5.6 | Drag Coefficient Inversely Proportional to Mach Number | 93 |
5.7 | Drag Coefficient Inversely Proportional to the Square Root of Mach Number | 94 |
5.8 | Comparison of Flat-Fire Trajectory Approximations | 95 |
5.9 | Summary | 96 |
Chapter 6 | The Siacci Method for Flat-Fire Trajectories | 98 |
6.1 | Introduction | 98 |
6.2 | Siacci Assumptions and Approximations | 98 |
6.3 | Derivation of the Siacci Functions | 98 |
6.4 | The Computation of Siacci Ballistic Tables | 101 |
6.5 | The Practical Use of the Ballistic Tables | 101 |
6.6 | Form Factors of Typical Small Arms Projectiles | 106 |
6.7 | The Effect of Projectile Shape on the Form Factor | 106 |
6.8 | Rules for the Use of the Form Factor Charts | 111 |
6.9 | Additional Notes on Form Factors | 111 |
Chapter 7 | The Effect of Wind on Flat-Fire Trajectories | 157 |
7.1 | Introduction | 157 |
7.2 | Equations of Motion | 157 |
7.3 | The Flat-Fire Approximation | 158 |
7.4 | The Effect of a Constant Crosswind on the Flat-Fire Trajectory | 158 |
7.5 | The Effect of a Variable Crosswind on the Flat-Fire Trajectory | 159 |
7.6 | The Effect of Rangewind on the Flat-Fire Trajectory | 162 |
7.7 | Summary | 164 |
Chapter 8 | The Point-Mass Trajectory | 165 |
8.1 | Introduction | 165 |
8.2 | Equations of Motion | 165 |
8.3 | Change of Independent Variable from Time to Distance | 165 |
8.4 | Numerical Solution of the Equations of Motion | 166 |
8.5 | Standard Atmospheres for Point-Mass Trajectories | 166 |
8.6 | Examples of Point-Mass Trajectories | 169 |
8.7 | Comparison of Point-Mass and Siacci Trajectories | 172 |
8.8 | The Coriolis Effect on Point-Mass Trajectories | 178 |
8.9 | Summary | 183 |
Chapter 9 | Six-Degrees-of-Freedom (6-DOF) and Modified Point-Mass Trajectories | 187 |
9.1 | Introduction | 187 |
9.2 | Equations of Motion for Six-Degrees-of-Freedom Trajectories | 187 |
9.3 | Initial Conditions for Six-Degrees-of-Freedom Trajectories | 191 |
9.4 | Numerical Solution of Six-Degrees-of-Freedom Trajectories | 193 |
9.5 | Examples of Six-Degrees-of-Freedom Trajectories | 194 |
9.6 | Summary and Comments on Six-Degrees-of-Freedom Trajectories | 212 |
9.7 | The Modified Point-Mass Trajectory Model | 212 |
9.8 | Examples of Modified Point-Mass Trajectories | 214 |
Chapter 10 | Linearized Pitching and Yawing Motion of Rotationally Symmetric Projectiles | 221 |
10.1 | Introduction | 221 |
10.2 | Equations of Motion for the Linearized Problem | 221 |
10.3 | Solution of the Differential Equations for Velocity and Spin | 228 |
10.4 | Simplified Pitching and Yawing Motion of a Spinning Projectile | 229 |
10.5 | The Classical Gyroscopic Stability Criterion | 230 |
10.6 | The Yaw of Repose for Spin-Stabilized Projectiles | 231 |
10.7 | Initial Conditions for Simplified Epicyclic Motion | 231 |
10.8 | Complete Linearized Pitching and Yawing Motion of Projectiles | 232 |
10.9 | Gyroscopic and Dynamic Stability of Symmetric Projectiles | 233 |
10.10 | Initial Conditions for Damped Epicyclic Motion | 234 |
10.11 | An Example of the Linearized Pitching and Yawing Motion | 235 |
10.12 | The Motion of the Rotating [i, j, k] Coordinate System | 236 |
10.13 | Pitching and Yawing Motion of a Slightly Asymmetric Missile | 237 |
10.14 | Summary | 238 |
Chapter 11 | Linearized Swerving Motion of Rotationally Symmetric Projectiles | 240 |
11.1 | Introduction | 240 |
11.2 | The Differential Equation of Swerving Motion | 240 |
11.3 | Solution of the Differential Equation for Swerve | 243 |
11.4 | Discussion of the Linearized Swerving Motion | 244 |
Chapter 12 | Lateral Throwoff and Aerodynamic Jump | 252 |
12.1 | Introduction | 252 |
12.2 | Derivation of the Lateral Throwoff Effect | 254 |
12.3 | The Effect of a Slight Mass Asymmetry on the Initial Pitching and Yawing Motion of a Spinning Projectile | 255 |
12.4 | The Generalized Aerodynamic Jump Effect | 259 |
12.5 | The Effect of Mass Asymmetry on Lateral Throwoff and Aerodynamic Jump | 260 |
12.6 | Derivation of Kent's Equation for a Small Mass Asymmetry | 264 |
12.7 | The Effect of In-Bore Yaw on Lateral Throwoff and Aerodynamic Jump | 264 |
12.8 | Derivation of Kent's Equation for a Small In-Bore Yaw | 266 |
12.9 | The Aerodynamic Jump Due to Crosswind | 267 |
12.10 | Firing Sidewise From an Airplane | 270 |
12.11 | Summary | 272 |
Chapter 13 | Nonlinear Aerodynamic Forces and Moments | 273 |
13.1 | Introduction | 273 |
13.2 | Analysis of Nonlinear Drag Coefficient Data | 273 |
13.3 | Quasi-Linear Analysis of a Cubic Pitching Moment | 275 |
13.4 | The Effect of a Cubic Pitching Moment on Stability | 279 |
13.5 | Pitching and Yawing Motion With All Nonlinear Moments | 280 |
13.6 | Bi-Cubic and Tri-Cubic Magnus Moments | 284 |
13.7 | Nonlinear Magnus Moments and Limit-Cycle Yawing Motion | 287 |
13.8 | Quasi-Linear Analysis of a Cubic Lift Force | 293 |
Chapter 14 | Measurement of Aerodynamic Forces and Moments | 299 |
14.1 | Introduction | 299 |
14.2 | Wind Tunnel Methods | 299 |
14.3 | Free-Flight Ballistic Ranges | 303 |
14.4 | Classical Data Reduction for Spark Photography Ranges | 304 |
14.5 | Six-Degrees-of-Freedom Data Reduction for Spark Ranges | 317 |
14.6 | Modern Data Reduction for Yaw-Card Firings | 318 |
14.7 | Methods of Yaw Induction | 320 |
14.8 | Yawsonde Testing | 323 |