Another United flight experienced a right engine failure in 2018

The dramatic engine failure on a United flight flung debris across neighborhoods outside Denver and caused the airline to ground more than 20 planes out of caution. It's the second time in three years that the right engine failed during a United flight. In 2018, a Boeing 777 bound for Honolulu lost the cover to its right engine mid-flight. Though the plane safely landed, the passengers onboard were terrified. Like the plane involved in Saturday's engine failure, the Boeing in 2018 was headed for Hawaii, too. Both were powered by engines from the same company. Investigators haven't yet determined the cause of Saturday's engine failure. If the outcome is the same as in 2018, the engine's fan blades may have played a part. In February 2018, United Airlines Flight 1175 took off from San Francisco toward Honolulu. More than 370 people were on board. Less than an hour away from the Hawaii capital, passengers heard pieces of metal rattling loudly, and the plane started to shake. Outside, the plane's right engine was exposed, its cover lost over the Pacific Ocean. The plane landed safely in Honolulu. The Boeing 777 involved in the 2018 incident was powered by Pratt & Whitney's PW4000 112-inch engines. The engine damaged on Saturday outside Denver was also a Pratt & Whitney engine, the PW4077. In its final report of the 2018 incident, the NTSB found that an engine blade failed and United mechanics didn't have the proper training to inspect blades.<br/>