Boeing jetliner that lost large panel mid-air was restricted from flights over water due to warning light

Alaska Airlines restricted the aircraft from long flights over water so it could return to an airport quickly if the warning light reappeared

The Boeing jetliner used in the Alaska Airlines flight that was forced to make an emergency landing in Portland, Oregon, after its door plug blew out in midair was not allowed to fly over water due to concerns about a warning light that lit up on three separate flights, a federal official announced Sunday.

Alaska Airlines restricted the aircraft from long flights over water to allow for the plane to return quickly to an airport if the warning light, which possibly indicated a pressurization problem, reappeared, National Transportation Safety Board chair Jennifer Homendy said during a news conference.

The warning light came on during flights on Dec. 7, Jan. 3 and Jan. 4. Homendy said she did not have all the details about the Dec. 7 incident but that the light came on during a flight on Jan. 3 and another on Jan. 4 after the plane had landed.

Homendy said that the pressurization light might be unrelated to Friday's accident in which a plug covering an unused exit door blew off the Boeing 737 Max 9 at an altitude of about 16,000 feet just minutes into a flight from Portland to Ontario, California, forcing an emergency landing back at Portland International Airport.

FAA TO TEMPORARILY GROUND CERTAIN PLANES AFTER ALASKA AIRLINES DOOR BLEW OFF IN MID-AIR

Plane section blown off in flight

Alaska Airlines Flight 1282 had been bound for Ontario, California, and suffered depressurization soon after departing in Portland, Oregon. (Reuters)

She added that it was fortunate the plane had not reached a cruising altitude of at least 30,000 feet when the accident took place as passengers and flight attendants could have been walking around the cabin.

Nobody was sitting in the two adjoining seats next to the blown-out door plug and none of the flight's 171 passengers, two pilots and four flight attendants suffered serious injuries.

WHAT TO KNOW ABOUT THE BOEING 737 MAX 9 PANEL THAT BLEW OFF IN MID-AIR

The lost door plug was located Sunday near Portland by a school teacher who found it in his backyard, according to the NTSB. Investigators will examine the plug to try and determine how it broke off the aircraft. 

Two cell phones that appeared to belong to passengers on Friday's flight were also recovered – one was discovered in a yard and the other on the side of a road. Both devices were turned over to the NTSB, which said it would return them to their owners.

Investigators will not be able to hear what was happening inside the cockpit during flight 1282 since the cockpit voice recorder taped over the flight’s sounds after two hours, according to Homendy.

Homendy also disclosed that the rapid decompression damaged several rows of seats and pulled insulation from the walls, and that the cockpit door flew open and banged into a lavatory door.

Plane passengers near missing panel

Passengers of Alaska Airlines flight 1282 sit near the panel that blew out in mid-air during a flight from Portland to Ontario, California. (Reuters)

ALASKA AIRLINES FLIGHT MAKES EMERGENCY LANDING IN PORTLAND AFTER SECTION OF PLANE BLEW OUT MID-AIR

The force of the air pulled the headset off the co-pilot and the captain lost part of her headset. A reference checklist located within reach of the pilots also flew out of the open cockpit.

Following the accident, the Federal Aviation Administration ordered a temporary grounding of 171 of the 218 Boeing 737 Max 9 planes in operation until they can be inspected.

The aircraft used for Friday's Alaska Airlines flight was delivered from Boeing in October.

Alaska Airlines and United Airlines are the only U.S. airlines to fly that particular model of Boeing's 737. Without some of their planes, the two airlines were forced to cancel over 600 of their flights.

Passenger oxygen masks hang from the roof next to a missing window and a portion of a side wall of Alaska Airlines Flight 1282.

Passenger oxygen masks hang from the roof next to a missing window and a portion of a side wall of Alaska Airlines Flight 1282. (Reuters)

The aircraft involved in Friday's accident came off the assembly line and received its certification two months ago, FAA records show. The plane had been used for 145 flights since entering commercial service on Nov. 11, according to FlightRadar24. The flight from Portland was the aircraft's third of the day.

The Max, which went into service in 2017, is the newest version of Boeing's 737, a twin-engine and single-aisle plane often used on U.S. domestic flights.

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Crashes involving Max 8 jets in Indonesia in 2018 and Ethiopia in 2019 left a total of 346 people dead. All Max 8 and Max 9 planes were grounded worldwide for nearly two years until Boeing made changes to an automated flight control system implicated in the crashes.

The Max has also faced other issues, including manufacturing flaws, concerns about overheating and a possible loose bolt in the rudder system.

The Associated Press contributed to this report.