On the Accuracy of Wind Measurements Using an Inertial Platform in an Aircraft, and an Example of a Measurement of the Vertical Mesostructure of the Atmosphere

Abstract

A high quality inertial navigation platform, originally developed for the TSR 2 aircraft, is now being used by the Meteorological Research Flight in order to measure vertical gust velocities and horizontal wind shear from a Canberra PR 3 aircraft. The equations are derived from which the vertical and horizontal winds are calculated, and an assessment is made of the accuracy of measurement which can be expected for vertical gusts and horizontal shear. Measurements of the residual error velocities which occur when the aircraft is made to pitch, roll and yaw are shown to lie within the theoretical limits, and an example of the velocities derived from a straight and level run in smooth air is also described. The use of this equipment to measure the small-scale variations in wind shear and vertical gusting when the aircraft descends through a layer of turbulence is then described, and the results of one of the first of a series of such flights are given. With the present recording system, the extraction of data for the analysis of a few minutes of flight is lengthy, but it is hoped that a data recording system will be installed in the future. The system will then become a quick and accurate method of measuring the mesoscale structure of the gusts and shears in the atmosphere.