Airlines around the world have grounded Boeing 777 aircraft with the same engine type as the United Airlines flight from Denver to Honolulu that suffered an engine failure on Feb. 20.
Saturday's incident, which scattered debris across several Denver-area neighborhoods but resulted in no injuries aboard the aircraft or on the ground, involved a 777-200 aircraft equipped with Pratt & Whitney's PW4000 engine. The U.S. Federal Aviation Administration has since ordered emergency inspections of that aircraft type with that engine type, and the Japan Civil Aviation Bureau also ordered them grounded.
In a statement, Boeing said it supported those regulators' decisions and that it is "working with these regulators as they take actions while these planes are on the ground and further inspections are conducted by Pratt & Whitney." In total, there are 69 777s with that engine type in active use and an additional 59 in storage, according to Boeing. It's an older and less fuel-efficient model that operators generally have been phasing out of fleets.
United is the only U.S. carrier with that sort of aircraft, and it has removed 24 of its type from its schedule, according to the carrier. That will affect "only a small number of customers," the carrier said in a tweet.
In Japan, the grounding affects 19 aircraft operated by All Nippon Airways and 13 operated by Japan Airlines, each of which had preemptively grounded the aircraft prior to the bureau's order, according to Nikkei Asia.
South Korean carriers Asiana and Korean Air are the only other carriers using the model. A Korean Air spokesperson said all PW4000-powered 777s are grounded as the airline awaits guidance from regulators, and media reports indicate that Asiana has grounded them as well. Korean Air flies the 777s on domestic routes and to destinations in China, Japan and in Southeast Asia, according to the spokesperson.
Saturday's incident was not the first instance of failure of the engine type in that aircraft. In December, a JAL 777-200 aircraft had to return to the airport after engine failure, and another United 777-200 aircraft in February 2018 also had engine failure when a fan blade fractured as it neared Hawaii. Both aircraft in those incidents landed safely.