BOSTON — A late afternoon flight with nine passengers aboard the Boston-bound Cape Air flight to Boston got a little windier Aug. 9 when the upper portion of the door opened.

According to Cape Air spokeswoman Michelle Lohr, the Cessna 402 landed without incident at Logan International Airport in Boston.

The Cessna had departed Rockland for a regular flight to Boston, and at approximately 4:20 p.m., just 15 minutes from Boston, the window part of the door came unlatched and opened.

The plane, which is not pressurized, made a safe landing, said Lohr. The weather was sunny, with light breezes.

“The pilot talked to all the passengers,” she said. “It is a little disconcerting, of course.”

The window and the door remained intact on the plane, she said.

The pilot called for a priority landing at Logan.

All nine passengers were fine, said Lohr.

The Federal Aviation Administration is to investigate, according to a spokesman for the federal agency.