August 26, 2013 – (Above) A helicopter, doing “second unit” filming for Transformers 4, flies through the raised Dearborn Street Bridge on Sunday morning. The bridges at Dearborn, State, and Wabash were raised at about 7:30 a.m. to accommodate the low-flying helicopter, which made about six passes over two hours.

This same stunt was performed on August 21, 2010 for a six-second shot that made it into the previous Transformers sequel.

Earlier in the morning, a helicopter flew low over the Chicago River while filming for Jupiter Ascending, another science fiction film being shot in Chicago this summer.

(Left) The helicopter flies low over the Clark Street Bridge. (Click on images to view larger versions.)

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