Spark Range

Data Reduction & Analysis

Arrow Tech engineers are experts at the reduction of test data from munitions testing.  We have sophisticated computer tools to accept data from several common firing range instrumentation systems including:

  • Spark Range
  • Doppler Radar
  • Yaw Card
  • Yaw Sonde 

Our proven methodology coupled with highly experienced engineers allows us to extract high quality results from the raw test data.  Our approach is to fit the test data to the equations of motion of the round in flight and continually refine the fit and extract the aerodynamic coefficients of the projectile.  We also help our customers with test design to ensure that expensive testing will produce the information required with an acceptable level of statistical confidence. 

Ballistic Solvers for Fire Control Systems

Arrow Tech has extensive experience with the development of Ballistic Solution Algorithms (BSA) for gun fire control systems in a wide variety of applications.  Our experience dates back 20 years and includes the development of ballistic solvers for fighter aircraft, turreted gun systems and infantry weapons.  Two recent applications include the development of the ballistic solver for a 40mm grenade weapon system and another for a shoulder fired rocket launcher.  We have also been involved in the development of solvers for several 0.50 caliber and 7.62mm systems.

We offer a mature development process that always starts with a truth model of the ammunition.  The truth model is typically a 6 Degree of Freedom (DOF) simulation that has been carefully validated with aeroballistic test data but is also augmented with published firing tables.  This model is used throughout the development process to ensure the accuracy of the embedded solver.

Arrow Tech has developed 4 DOF simulation algorithms suitable for use in fire control computers where computational resources are limited. These algorithms use a unique variable step, distance based numerical integration scheme that has been proven to have significant computational performance advantages over traditional numerical integration schemes.  This approach offers improved accuracy with little or no sacrifice in computation time over other approaches.  This 4 DOF approach is also compatible with NATO STANAG 4355 Modified Point Mass Model. Further, this approach makes maintenance of the solver a simple matter of updating projectile physical characteristics and aerodynamic data if a change is made or a new projectile design is added to the ammunition family.

Our goal is to partner with potential hardware developers of future fire controls as the developer of the BSA and perhaps other fire control software.

fire control systems

fire control systems

aerodynamic prediction tools

Aero Prediction Tools for Spin & Fin Stabilized Projectiles

  • Spinner 2004 and Finner 2003 Prediction Algorithms
    • Empirical database containing all of the ballistic shapes tested within the North American Spark Ranges since 1938 (200 + Shapes)
    • Spin Stabilized Coefficients - CX0 CX2 CX4 CNa CNa3 CPN CYpa CXf CXb CNq Cma Cma3 Cma5 Cmq Cmq2 Clp Cld Magnus Moment Derivative – Cnpa vs angle of attack Magnus Moment Coefficient – Cnp vs angle of attack
    • Fin Stabilized Coefficients - CX0 CX2 CX4 CNa CNa3 CPN CYpa CXfore CXbase CNq Cma Cma3 Cma5 Cmq Cmq2 Clp Cld CYga CZga Clga Cmga Cnga Csm Czd Cmd  
  • Additional Aero Prediction Capability
    • NEAR MISL 3 Algorithm (Missile Shapes)
    • Missile DATCOM Interface (US Air Force Missile Aero Predictor)*
    • Aero Prediction (AP 98) (US Navy Aero Prediction Routine)*•
      • * Available only if customer has documented copy of baseline engineering algorithm 
  • Aero Direct Input
    • Baseline Aeros, Magnus Aeros, Staged Aerodyanmics, Fin Aeros, Assymetric Aeros, High Alpha Aeros, Direct CFD and Wind Tunnel inputs
  • Aero Manager
    • Allows plotting and modification of multiple sources of aero data