Extendable mast

An extendable mast constructed by freely swingably connecting a plurality of essentially rigid members to one another comprising:

• a plurality of battens extending transversely of the mast;
• a plurality of longerons extending longitudinally of the mast to connect adjacent battens;
• diagonals arranged along diagonal lines of a plurality of rectangles arranged between adjacent battens and around the periphery of said mast, with each of said plurality of rectangles being formed by two longerons adjacent to each other transversely of the mast and two of said plurality of battens adjacent to each other longitudinally of the mast, wherein each of said diagonals includes plural slider members which are extended by sliding said plural slider members relative to each other, and a maximum length of such diagonal is defined by means for limiting the extent to which the slider members are slid relative to each other;
• each of said plurality of longerons includes a pair of first and second beam members, wherein respective opposed ends of these beam members are freely swingably connected to each other while ends thereof remote from each other are freely swingably connected to adjacent ones of said plurality of battens, wherein the extendable mast is extended when these beam members are deployed and locked under overcenter conditions with said diagonals being extended to their longest length;
• and
• wherein at least a portion of one of the said pair of first and second beam members is received in the other of said pair when the mast is folded and said pair of beam members is folded on one another.