/**
* Method to calculate the distance to a waypoint
*
* @param dest lat, lon
* @return distance to waypoint in Rad
*/
public double getDistanceRad(double latDecD, double lonDecD) {
double phi1 = this.latDec * PiOver180;
double lambda0 = this.lonDec * PiOver180;
double phi = latDecD * PiOver180;
double lambda = lonDecD * PiOver180;
double pdiff = Math.sin(((phi - phi1) / 2.0));
double ldiff = Math.sin((lambda - lambda0) / 2.0);
double rval = Math.sqrt((pdiff * pdiff) + Math.cos(phi1) * Math.cos(phi) * (ldiff * ldiff));
return 2.0 * Math.asin(rval);
}
