One flyer recorded the nerve-wracking arrival at LAX. The cabin broke out in applause after the plane safely put wheels down and began slowing to taxi on the tarmac.
There were 175 passengers and six crew members on Flight 309, which landed safely at LAX around 8 p.m. with no reported injuries, according to the airline.
Those passengers included dozens of Orange County middle school students returning from a field trip to Washington.
"I had to remain really calm for my daughter," said passenger Allison Mueller of Virginia. "I was scared."
The gear problem was observed shortly after takeoff from Dulles International Airport.
The cabin crew reported over the radio feeling a "jolt" strong enough to pop open some overhead luggage bins and trigger one emergency oxygen mask to fall from the ceiling.
Passengers reported hearing a "loud pop" and feeling the plane shake after takeoff.
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The crew asked the airport to check the runway at Dulles to see if perhaps they ran over something on the surface or if they did in fact lose some of the tire. Crews checked the tarmac surface and confirmed finding pieces of tire.
The landing gear still retracted properly and the crew decided to continue the flight as scheduled.
"There's no reason we can see to discontinue the flight at this point," a cabin crew member is heard saying on radio traffic. "Just press on to Los Angeles and take care of it there."
The flight crew declared an emergency as a precaution and fire engines could be seen ready nearby at LAX as the plane landed. LAX officials say the plane was able to safely taxi on its own to the gate without additional disruption to airport operations.
The passengers were alerted to prepare about an hour before landing.
"They got us in the brace position," said passenger Brent Drewette of San Juan Capistrano. "It was 10 seconds of really violent shaking. But then emergency crews checked and they brought us in and everything was fine."
Alaska Airlines says the Boeing 737-900 will be pulled from service while the incident is investigated.
"While this incident is a rare occurrence, our flight crews train extensively to safely manage through many scenarios," Alaska Airlines said. "We understand this might have been a concerning moment for our guests on board. We apologize for what they experienced."