Four Wheel Steering
Grappling Hook
How does Batman get the Batmobile down from that building?
Answer from Batman Forever Goof/Faq
He activates the jet boosters, flys over and *onto* the roof,
    bypassing the grappling hook, disengaging the connecting cable, and
    then drives from roof to roof, until he hits land.  See diagram. 
    
        
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