Aircraft traffic control

Claim 1

APPARATUS FOR SIMULTANEOUSLY DIRECTING A PLURALITY OF AIRCRAFT TOWARD A COMMON POINT OF ENTRY TO A LANDING AREA, COMPRISING MEANS AT A CONTROL STATION FOR OBSERVING THE RANGE, AZIMUTH, HEADING AND AIR SPEED OF EACH CRAFT BY SUCCESSIVE TRACKING OPERATIONS INITIATED IN EACH INSTANCE BY APPREHENSION OF SIGNALS REPRESENTING RADAR PULSE ECHOES REFLECTED FROM SAID CRAFT, COMPUTER MEANS HAVING INPUT CIRCUITS UTILIZING THE PULSE ECHO SIGNALS APPREHENDED BY SAID OBSERVING MEANS FOR SELECTING FOR THE FIRST APPREHENDED CRAFT AN APPROACH PATH "A" TERMINATING AT SAID ENTRY POINT, WHICH PATH "A" CAN BE FLOWN BY SAID CRAFT, AT ITS OBSERVED AIR SPEED AND UNDER THE PREVAILING WIND AND ALTITUDE CONDITIONS WITHIN AN ALLOTTED APPROACHTIME PERIOD OF "N" UNITS OF TIME, MEANS FOR SELECTING FOR THE NEXT APPREHENDED CRAFT AN APPROACH PATH "B" TERMINATING AT SAID ENTRY POINT, WHICH PATH "B" CAN BE FLOWN BY SAID SECOND CRAFT, AT ITS OBSERVED AIR SPEED AND UNDER THE PREVAILING WIND AND ALTITUDE CONDITIONS, WITHIN AN ALLOTTED APPROACH-TIME PERIOD OF "N" PLUS "C" TIME UNITS, WHEREIN "C" HAS A VALUE EQUAL TO AN INTEGRAL MULTIPLE OF THE TIME INTERVAL "1" PRE-SELECTED AS THE LENGTH OF TIME THAT SHOULD ELASPE BETWEEN ENTRY POINT ARRIVALS OF TWO CONSECUTIVELY APPROACHING CRAFT, SAID OBSERVING MEANS INCLUDING PHOTO-ELECTRICALLY RESPONSIVE MEANS FOR CONVERTING RADAR SCOPE ILLUMINATION SIGNALS INTO RANGE AND AZIMUTH VOLTAGE SIGNALS, AND MEANS INCLUDING RANGE AND AZIMUTH MEMORY CIRCUITS FOR CONTINUOUSLY TRACKING THE CRAFT INDENTIFIED BY SAID ILLUMINATION SIGNALS.