Aircraft propulsion system

Claim 1

IN AN AIRCRAFT PROPULSION SYSTEM, ROTOR BLADE MEANS, ROOT SHAFT MEANS PIVOTALLY CONNECTED ABOUT A TRANSVERSE AXIS THEREOF TO SAID ROTOR MEANS IN SUCH A MANNER AS TO PERMIT SAID ROTOR MEANS TO BE FOLDED, DRIVE SHAFT MEANS ADAPTED TO BE DRIVINGLY CONNECTED TO PRIME MOVER MEANS, HUB MEANS CONNECTED TO SAID DRIVE SHAFT MEANS AND PIVOTALLY SUPPORTING SAID ROOT SHAFT MEANS THEREIN, FIRST COLLAR MEANS ENCIRCLING AND SLIDABLY DISPOSED ABOUT SAID DRIVE SHAFT MEANS, SECOND COLLAR MEANS JOURNALED ABOUT SAID ROTOR MEANS ADJACENT SAID ROOT SHAT MEANS, GUIDE LINK MEANS PIVOTALLY CONNECTED TO SAID FIRST COLLAR MEANS AND TO SAID SECOND COLLAR MEANS, AND SPRING MEANS DISPOSED ABOUT AND CARRIED BY SAID DRIVE SHAFT MEANS AND URGING SAID FIRST COLLAR MEANS TOWARD SAID ROTOR MEANS FOR URGING SAID ROTOR MEANS TO AN ERECT OPERABLE POSITION, AND SAID SPRING MEANS BEING STRONG ENOUGH TO PREVENT THE RETRACTION OF SAID ROTOR MEANS UNTIL DRAG FORCES ON SAID ROTOR MEANS EXCEED ANY THRUST GENERATED BY SAID ROTOR MEANS BY AN AMOUNT SUFFICIENT TO COMPRESS SAID SPRING MEANS.