It was pure luck that no one was sitting in 2 Alaska Airlines seats that feds say got 'torqued' when a door blew off mid-flight

• An Alaska Airlines flight had a door plug blow off the plane mid-flight on Friday.
• The violent force of the panel ripping off the plane caused two of the seats to "torque," feds said.

A door-like panel blew off the side of an Alaska Airlines plane mid-flight on Friday — and two of the most damaged seats on the plane just so happened to have no one sitting in them.

National Transportation Safety Board Chair Jennifer Homendy said at a news conference Sunday evening that seats in 12 cabin rows were damaged.

And the sheer force of the door plug — a panel built into the plane that could optionally be turned into an emergency exit door — blowing off midair was so violent that seats 26A and 25A had "torqued," Homendy said.

"The seats in 26 and 25 were torqued, and there was a lot of damage to the interior paneling trim," Homendy said at Sunday's conference. "So my impression when I saw that is it must have been a terrifying event to experience."

The seats' headrests had also ripped off, and one lost its seatback tray table.

Luckily, those two seats just happened to have been empty, according to Homendy. There were only five other empty seats on the 178-seat Boeing 737 Max 9, which had been traveling from Portland, Oregon, to Ontario, California.

About 10 minutes into the flight, while the plane was still ascending, passengers heard "a really loud bang" and felt "a jolt and a whoosh of air" when the panel blew off, causing oxygen masks to drop down, Business Insider previously reported.

The plane was able to land back in Portland after the incident safely. The NTSB is investigating what exactly caused the malfunction, and in the meantime, all Boeing 737-9 MAX planes have been grounded.