(iv) Jet-propelled radio-controlled glider bombs (Hs 293), which enable the parent aircraft to operate beyond the range of effective A/A fire, and glider bombs without power unit or remote control (Bv 246). (v) High-level radio-corrected armour-piercing bombs (FX 1400 Kg.) (vi) Liquid explosives (possibly used in A-4 long-range rocket). (vii) Proximity fuzes. (viii) Hollow-charge bombs on "follow through" principle. (ix) Long-range rocket (A-4) of an estimated weight of 9-14 tons. 11. In the Me 163 liquid-rocket aircraft the Germans have a unique development which holds some promise as an interceptor, but which is seriously handicapped by lack of endurance.