The 55mm R4M Orkan (Tornado) folding fin missile was a formidable weapon fitted to Me 262s late in the war. Twenty-Four R4Ms were mounted on special wooden racks mounted under the wings. Each rack held twelve missiles which were about 2 ft. 8 ins. long and weighed 8.8 lbs. When fired, the missile traveled up to 1,700 ft/sec and packed a 1.1 lb. impact fused warhead. The warhead was typically white with the rest of the body and fins being a gray or dark metallic color.
The R4Ms were usually fired in four salvos of six missiles each at intervals of 0.07 seconds from a range of 600 meters. The R4M was unguided and the pilot simply used the usual Revi gunsite for aiming. When launched, the spring loaded fins would unfolded rearward. This enabled the R4M to be extremely compact until fired when the fins unfolded to provide stabilization. Seven of the fins were kept folded in place with a spring steel wire. The eighth fin then folded to hold the wire in place. When loaded from back to front in the launcher, the eighth (top) fin was kept in place by the launch rail. Once free of the rail when fired, the top fin would spring free and release the other seven fins.
The launchers were aimed with a slight upward angle of 8 degrees. When the rockets were fired from a range of 600 meters, they had the same ballistics as the Mk 108 cannons. The warhead was a 55 mm HE shell filled with Hexogen. A single hit was all that was needed to bring down a four engined bomber.
