Coordinate destination computer

Claim 1

A NAVIGATIONAL COMPUTER FOR CALCULATING POSITION WITH RESPECT TO A FIRST POINT AND ANY ONE OF A PLURALITY OF DESIGNATED TRACKS PASSING THERETHROUGH, COMPRISING A FIRST SETTABLE STORAGE MEANS FOR STORING THE REFERENCE ANGLE OF A FIRST ONE OF SAID DESIGNATED TRACKS, A SECOND SETTABLE STORAGE MEANS FOR STORING THE REFERENCE ANGLE OF A SECOND ONE OF SAID DESIGNATED TRACKS, MEANS FOR SUPPLYING SIGNALS REPRESENTING THE TRACK MADE GOOD AND THE DISTANCE TRAVELLED FROM A SECOND POINT LYING ON SAID FIRST TRACK AT A KNOWN DISTANCE FROM SAID FIRST POINT, SUBTRACTING MEANS HAVING A FIRST INPUT CONNECTED TO SAID SIGNAL SUPPLYING MEANS AND A SECOND INPUT SWITCHEDLY CONNECTED TO ONE OF SAID STORAGE MEANS FOR SUPPLYING A DIFFERENCE SIGNAL REPRESENTING THE DIFFERENCE BETWEEN THE TRACK MADE GOOD AND ONE OF SAID REFERENCE TRACKS, FIRST COMPUTING MEANS RESPONSIVE TO SAID SUBTRACTING MEANS AND TO THE SIGNAL REPRESENTING THE DISTANCE TRAVELLED FROM SAID SECOND POINT TO CALCULATE POSITION WITH RESPECT TO SAID SECOND POINT AND SAID FIRST TRACK, SECOND COMPUTING MEANS RESPONSIVE TO SAID FIRST COMPUTING MEANS TO CALCULATE POSITION WITH RESPECT TO SAID FIRST POINT AND SAID FIRST TRACK, THIRD COMPUTING MEANS OPERABLE IN A FIRST CIRCUIT CONFIGURATION RESPONSIVE TO SIGNALS REPRESENTING POSITION FROM SAID SECOND COMPUTING MEANS AND SAID DIFFERENCE SIGNAL TO CALCULATE RANGE AND RELATIVE TRACK TO SAID FIRST POINT, SAID THIRD COMPUTING MEANS BEING OPERABLE IN A SECOND CIRCUIT CONFIGURATION RESPONSIVE TO SAID DIFFERENCE SIGNAL AND TO SIGNALS REPRESENTING RANGE AND RELATIVE TRACK STORED IN SAID THIRD COMPUTING MEANS TO CALCULATE POSITION WITH RESPECT TO SAID FIRST AND SAID SECOND TRACK, SEQUENCE SWITCHING MEANS CONTROLLING SAID THIRD COMPUTING MEANS FOR SELECTIVELY ESTABLISHING SAID FIRST OR SECOND CIRCUIT CONFIGURATION.