Our columnist ponders the relative merits of one, two, three and four engines in a business jet.
Some people tried to convince Charles Lindbergh that he shouldn’t attempt his 1927 New York-to-Paris flight in an airplane with only one engine. His response was that two engines would double his odds of having an engine failure. In the graveyard humor of pilots, the saying goes, “The second engine will take you directly to the scene of the accident.” So Lucky Lindy chose a single Wright J5 Whirlwind to power the Spirit of St. Louis, and the rest is history.
But he wasn’t carrying passengers.
These days, the reliability and efficiency of 21st century turbofan engines is nothing short of astounding. Simplicity of design, strict quality control and impeccable maintenance make them practically immune to mechanical failure. We fly so much that eventually the law of averages will catch up and a flock of geese will precipitate “the unlikely event of a water landing” in full view of New York City. People remember that for a long time. What goes unnoticed are the millions of hours of uninterrupted, routine engine operation before, and since, the Miracle on the Hudson.
The reliability of modern turbine engines is why most airliners today have two of them, rather than three or four as was once the case. Though it’s less expensive for the airlines to feed and care for only two, the world’s aviation authorities wrung their collective hands for a long time before adopting so-called Extended-Range Twin Operations, better known as ETOPS. The rules set strict criteria for reliability that enabled twin-engine jets to operate over water in places that were 60, 90, 120 or more minutes from a suitable airport. The dark-humor “backronym” for ETOPS is “Engines Turn Or Passengers Swim.”
Source: www.bjtonline.com; Mark Phelps; June 2014.