Loft-bombing system

Claim 1

A NAVIGATIONAL APPARATUS FOR DISPLAYING THE GROUND TRACK OF AN AIRCRAFT IN FLIGHT, COMPRISING: A MAP MOVABLE ALONG AN ON-COURSE AXIS RELATIVE TO AN INDEX, MEANS FOR DRIVING SAID MAP ALONG SAID AXIS, SAID MAP DRIVING MEANS HAVING AN INPUT SIGNAL PROPORTIONAL TO THE AIRSPEED OF THE AIRCRAFT AND RATE CORRECTION MEANS FOR MODIFYING SAID INPUT SIGNAL TO A RATE PROPORTIONAL TO THE ON-COURSE COMPONENT OF THE AIRCRAFT GROUND SPEED, STEP CORRECTION MEANS FOR PERIODICALLY SKIPPING SAID MAP AN AMOUNT EQUAL AND OPPOSITE TO THE CUMULATIVE ERROR BETWEEN THE INDICATED AND ACTUAL POSITION OF THE AIRCRAFT, A CURSOR MOVABLE ALONG A CROSS-COURSE AXIS NORMAL TO SAID ON-COURSE AXIS IN FRONT OF SAID MAP, AND MEANS FOR DRIVING SAID CURSOR ALONG SAID CROSS-COURSE AXIS AT A RATE PROPORTIONAL TO THE CROSS-COURSE COMPONENT OF THE AIRCRAFT GROUND SPEED; WHEREBY THE INDICATED INSTANTANEOUS POSITION OF THE AIRCRAFT ON SAID MAP AT THE INTERSECTION OF SAID INDEX AND SAID CURSOR CONTINUOUSLY CORRESPONDS TO THE INSTANTANEOUS POSITION OF THE AIRCRAFT RELATIVE TO THE GROUND.