USING FORECAST METEOROLOGICAL DATA TO REDUCE THE ARTILLERY ERROR BUDGET

摘要

An unguided Artillery shell fired from guns to ranges greater than 15km canexperience significant perturbations that result in large delivery errors. There are anumber of sources of error, the largest of which can be the estimation of themeteorological (Met.) parameters along the trajectory (pressure, temperature,humidity (PTU) and the wind vector).The most effective way to minimise the meteorological errors is to launch balloonsfilled with hydrogen, carrying sondes that measure the parameters up to an altitudeof 20km, the maximum ordinate for current Artillery shell. The data is then sent to thecontrol station and used to generate a one-dimensional (1-d) Met. message that isused in the fire control ballistic solution to adjust the quadrant elevation and azimuthof the gun. The 1-d message is only a snapshot of the meteorological variability andis subject to considerable spatial and temporal error. These errors can be significant(up to 70% of the accuracy, or bias, error). In addition, the logistics involved incollecting the data is considerable and a burden on the Artillery units.Over the last 10-15 years, meteorological forecasting techniques have improvedsignificantly. A number of nations now have Weather Analysis Centres (WACs)capable of extracting accurate meteorological parameters for a region of interest fromthe Global mesoscale model. These forecasts can be produced as a 4-d message(space and time) that can be used by future fire control systems to provide thecorrection for the meteorological conditions. In parallel with the enhanced capability,there has been significant effort in estimating the benefits of forecasting andvalidating the models to real world conditions.The paper presents the evolution of the Artillery error budget, providing the detailedmethodology that has been used to generate the current meteoroidal delivery errorsfor unguided shell. It examines the benefits of using modern forecasting technologyto replace the current balloon/sonde system in the field to generate the corrections toimprove the accuracy of Artillery fire. This paper suggests the optimum mix of datarequired to minimise the error budget and also highlights the benefits of forecastingdata for other Users such as rocket Artillery, guided shell and NBC dispersion