/// <summary>
/// Computes the required takeoff distance.
/// </summary>
/// <exception cref="Exception"></exception>
public static double TakeOffDistanceMeter(AirbusPerfTable t, TOParameters p)
{
var tables = GetTables(t, p);
if (tables.Count == 0)
{
throw new Exception("No data for selected flaps");
}
var pressAlt = ConversionTools.PressureAltitudeFt(p.RwyElevationFt, p.QNH);
var inverseTables = tables.Select(x => GetInverseTable(x, pressAlt, t, p));
var distancesFt = inverseTables.Select(x =>
x.ValueAt(p.WeightKg * 0.001 * Constants.KgLbRatio))
.ToArray();
var d = (distancesFt.Length == 1) ?
distancesFt[0] :
Interpolate1D.Interpolate(
tables.Select(x => x.IsaOffset).ToArray(),
distancesFt,
IsaOffset(p));
// The slope and wind correction is not exactly correct according to
// performance xml file comments. However, the table itsel is probably
// not that precise anyways.
return(Constants.FtMeterRatio * (d - SlopeAndWindCorrectionFt(d, t, p)));
}
/// <summary>
/// Flaps and brake settings can be overriden.
/// </summary>
/// <exception cref="Exception">Unexpected error</exception>
public static double LandingDistanceMeter(CalculatorData d,
string flaps = null, string brake = null)
{
var p = d.Parameters;
var t = d.Table;
if (flaps == null)
{
flaps = t.AllFlaps()[p.FlapsIndex];
}
if (brake == null)
{
brake = t.AllBrakes()[p.BrakeIndex];
}
// Matching table
var m = t.Entries.Where(x => x.Flaps == flaps && x.Autobrake == brake)
.First();
var weight1000LB = p.WeightKG / 1000 * Constants.KgLbRatio;
var(table, elevation, head, tail, reverser) = p.SurfaceCondition == 0
? (m.Dry, m.ElevationDry, m.HeadwindDry, m.TailwindDry, m.BothReversersDry)
: (m.Wet, m.ElevationWet, m.HeadwindWet, m.TailwindWet, m.BothReversersWet);
var len = table.ValueAt(weight1000LB);
var alt = ConversionTools.PressureAltitudeFt(p.ElevationFT, p.QNH);
len *= 1 + alt / 1000 * elevation / 100;
len *= 1 + (p.HeadwindKts >= 0 ?
(-head * p.HeadwindKts / 10) :
(tail * -p.HeadwindKts / 10)) / 100;
len *= 1 - (p.Reverser == 1 ? reverser : 0) / 100;
len *= 1 + (p.AppSpeedIncrease / 5) * (m.Speed5Knots / 100);
return(len * Constants.FtMeterRatio * t.Multiplier);
}
private double RwyPressureAltFt()
{
return(ConversionTools.PressureAltitudeFt(para.RwyElevationFt, para.QNH));
}