Boris Ivanovich Cheranovskii pioneered tailless monoplanes, especially of 'parabola' form with curved leading edge. BICh-1 glider 1923, first powered aircraft -3 of 1926, successful. BICh-7 1929 unstable, rebuilt as -7A. BICh-10 and -14 twin-engined, -20 and -21 normal tapered wings, -26 projected supersonic fighter, Cheranovskii having previously tunnel-tested variable-sweep fighters with outboard pivots 1946-8.