Engine failure may be cause of helicopter crash near I-57, NTSB says

CHICAGO — Investigators have released new information of what may have caused a medical helicopter crash on the South Side near Interstate 57 earlier this month.

A preliminary report from the NTSB (National Transportation Safety Board) says it may have been caused by both engines failing.

The helicopter was flying from a hospital in Indiana to Christ Hospital in Oak Lawn.

The pilot sent out a Mayday call shortly before the crash.

Surveillance video from a nearby CTA station shows an explosion after the crash.

Three of the four people on-board were injured.

The NTSB is still reviewing data and will release a final report when the investigation is complete.