R/calcATTACK.R

In WilliamCooper/Ranadu: Functions for use with RAF aircraft data files

#' @title calcAttack
#' @description Calculate angle-of-attack
#' @details Assumes vertical wind = 0, finds AOA from pitch, VSPD and TASX. Used to
#' provide a reference value for calibrating gust probes. The radome "calibration"
#' coefficients are usually determined by fitting to reference values provided by
#' this function, so it should be used where it is expected that the vertical wind
#' is zero or averages to zero.
#' @aliases calcAttack
#' @author William Cooper
#' @export calcAttack
#' @param PITCH The pitch angle in degrees
#' @param VSPD  The rate of climb of the aircraft in m/s 
#' @param TASX  The true airspeed of the aircraft in m/s
#' @examples 
#' AOAREF <- calcAttack (RAFdata$PITCH, RAFdata$GGVSPD, RAFdata$TASX)
#' plot (RAFdata$ATTACK, calcAttack (RAFdata$PITCH, RAFdata$GGVSPD, RAFdata$TASX))
calcAttack <- function (PITCH, VSPD, TASX) {
  return (PITCH - (180./pi) * asin (VSPD/TASX))
}