If Batman were real (were? He is real!) he wouldn’t live very long, at least not with that cape. A new study did the math:
After accounting for the drag and lift forces acting on Bruce Wayne in flight, the doomed trajectory was calculated. The 15.4-foot wingspan is just half that of an ordinary hang glider and, when launching off an 492-foot-high Gotham city skyscraper and gliding (successfully, the team predicted) for around 1,150 feet, Batman’s velocity would peak at 68 mph before levelling off at a life-threatening 50 mph descent.