adjustable aerobridge air jetty airbridge aircraft door airport angle board boarding bridge cab connected connecting connection disconnect disconnected disembark disembarking enclosed extend extendable exterior gate gate attendant gateway height high interior jet bridge jetway loading bridge movable movable connector passenger boarding bridge passenger walkway passengers portal retractable retractable tunnel retracted retracting safety security slope sloping terminal walkway blade carpentry centimeter construction imperial inch measure measuring metal metric tape unit constructio calcium carbonate coiled coiled shells crawling exoskeleton eye stalks eyes friction garden snail gastropoda helix aspersa herbivorous land snails locomotion logarithmic spiral mantle mollusk movement mucus muscular foot olfactory organs ommatophores radula ripple rippling shell skin Slime slimy snail spirally tentacles terrestrial snails textured surface unsegmented 60 building detail flexible length meter numbers on white ruller size tool work workplace yellow steel rule tape measure tapeline acinonyx jubatus alert big-cats black spots carnivore carnivorous cat cheetah cheetahs distinctive distinguishing features fast felid feline fur mammal non-retractable claws reclining relaxed runner speed speed-bursts speedy spots spotted sprinter tamable tamed variegated coat