It appears like a nightmare situation for airplane passengers: You have a look out the window in between mini-pretzel bites to see an engine cloaked in flames, shedding items of metallic mid-flight from 10,000 toes within the air. That’s precisely the sight that greeted passengers of United Flight 328 on Saturday not lengthy after departing Denver for Honolulu.
A roughly 500,000-pound jet with one engine appears as seemingly a candidate to fly as a condor with one wing. And but for all of the hazard posed by the flambé Boeing 777 this weekend—and there was loads, significantly to the Denver suburbs subjected to large-scale particles shed by the aircraft’s Pratt & Whitney PW4077 engine—staying within the air was extraordinarily low on the listing. In truth, its remaining engine is theoretically sturdy sufficient to have made the rest of the flight by itself.
That wasn’t all the time the case for giant plane. For many years, the Federal Aviation Administration didn’t enable twin-engine planes to make journeys over an hour, a lot much less from the Midwest to a Pacific paradise. “It’ll be a cold day in hell before I let twins fly long-haul over-water routes,” then-FAA administrator Lynn Helms insisted when Boeing requested the FAA to vary the rule in 1980, in response to Robert J. Sterling’s 1991 historical past of the aerospace big. If an engine did fail, you’d have at the very least two others to depend on.
Eventually the FAA relented, increasing the 60-minute rule to 120 after which 180 minutes because the ’80s wore on. Credit improved engines for the change of coronary heart, reasonably than an elevated urge for food for danger.
“One engine has to have enough thrust to keep the airplane going, and even climbing if it needs to,” says Ella Atkins, an aerospace engineer on the University of Michigan. That applies even to a worst-case situation, she says, akin to shedding an engine whilst you’re within the strategy of taking off. The remaining engine must be sturdy sufficient, if required, to get you airborne by itself.
Which is to not say that engine failure is with out consequence, particularly when a hearth is concerned. It introduces a bunch of problems irrespective of the scale of the plane or the complexity of its automated methods. “Many pilots go through their entire career without a single engine failure, even though we train for it,” says Bob Meder, chairman of the National Association of Flight Instructors. “In general, you do your memory items first for the airplane you’re flying. You’ve got an engine fire, you secure the engine and stop the flow fuel to the engine.”