Joint Base San Antonio spokesman Brent Boller told the San Antonio Express-News the plane took off from Port San Antonio Thursday morning and did lose a part.
Melissa Gutierrez and her boyfriend, Nate Martinez, were startled by the loud scraping sound when the plane piece landed.
Martinez says some picture frames were knocked off the wall. Also, the couple's barbecue grill was minimally damaged.
Boller says there was no indication the plane itself was affected by losing the part.
Boeing spokesman Peter P. Pedraza says they are conducting an investigation into an "in-flight mishap" concerning a U.S. Air Force C-17.
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