It feels like A nightmare scenario for airplane passengers – you look out the window between mini pretzel bites to see an engine engulfed in flames, flinging chunks of metal mid-air from 10,000 feet into the air. That’s exactly the sight that greeted passengers on United Flight 328 on Saturday, shortly after leaving Denver for Honolulu.
An approximately 500,000 pound aircraft with one engine seems as likely a candidate for flying as a condor with one wing. And yet, despite all the danger posed by the Boeing 777 flamed this weekend, and there was plenty, particularly in the Denver suburbs subject to large-scale debris spewed by the aircraft’s Pratt & Whitney PW4077 engine, remain in the air it was extremely low on the list. In fact, its remaining engine is theoretically strong enough to have done the rest of the flight on its own.
That was not always the case for large airplanes. For decades, the Federal Aviation Administration did not allow twin-engine planes to make trips of more than an hour, much less from the Midwest to a Pacific paradise. “It will be a cold day in hell before I let the twins fly long-distance routes over water,” insisted then-FAA Administrator Lynn Helms when Boeing asked the FAA to change the rule in 1980, According to Robert J. Sterling from 1991. History of the aerospace giant. If one engine failed, you would have at least two others to rely on.
Eventually, the FAA relented, expanding the 60-minute rule to 120 and then 180 as the 80s progressed. Credit enhanced the engines for change of mind, rather than increased appetite for risk.
“An engine has to have enough thrust to keep the plane going, and even go up if necessary,” says Ella Atkins, an aerospace engineer at the University of Michigan. That applies to even the worst-case scenario, he says, like losing an engine while in the process of taking off. The remaining motor must be strong enough, if necessary, so that it can fly on its own.
Which is not to say that engine failure has no consequences, especially when it comes to a fire. It introduces a number of complications regardless of the size of the aircraft or the complexity of its automated systems. “Many pilots go their entire careers without a single engine failure, even though we train for it,” says Bob Meder, president of the National Association of Flight Instructors. “In general, you first make your memory elements for the plane you are flying. It has an engine on fire, secures the engine and stops the flow of fuel to the engine. “