Crosscheck: Crosswind Calc

Two lines of trigonometry, in the runup area, with the ATIS still in your head. Crosscheck does them and draws the answer. Type the runway and the wind. You get the crosswind and the head or tailwind, and — the part that matters — the runway drawn with the wind across it at the real angle, so which side it is on is unmistakable. Knowing the number is easy. Picturing the side wrong under pressure is what puts an aeroplane in the grass. THE GUST IS THE NUMBER THAT DECIDES Plan on the steady wind and land in the gust and you planned the wrong number. The headline figure is the gust; the steady one is underneath it, because you brief both. IT WORKS THE OTHER END WITHOUT BEING ASKED Every wind is computed for the reciprocal too. If that end is the better one — a headwind instead of a tailwind, or materially less across — the app says so with the numbers already on it, and swaps with one tap.…