With twin-engine jets becoming the norm these days, we thought we would take a look and see how far a modern twin-engine airliner can fly on one engine. Until not that long ago, transoceanic flights were nearly always flown with aircraft with four engines. This was because when it comes to how many engines a plane has, there is safety in numbers. If one engine was to fail, you still had three others to get you to your destination.
As modern turbofan engines develop, their reliability has led to far fewer engine failures, and of course, two engines burn much less fuel than their four-engine counterparts. As a result of this, airlines have rapidly adapted to the new fuel-efficient jets and are replacing thirsty aircraft like the Boeing 747, Airbus A340, and, unfortunately, everyone’s favorite Airbus A380.
Twin-engine jets are designed to fly on one engine
While engine failures these days are rare, they still happen from time to time, but you do not need to worry as modern jets are designed to fly safely on one engine. Before a twin-engine plane is allowed to fly routes over oceans or sparsely inhabited areas like the Arctic, they must first be certified by the Federal Aviation Administration (FAA) for ETOPS.
ETOPS stands for Extended-range Twin-engine Operational Performance Standards. It is a certification that permits twin-engine aircraft to fly routes, which may be an hour or more flying time from the closest airport where the plane can land safely.
ETOPS is how far a plane can fly on one engine
When the twin-engine aircraft is certified, part of its assessment is based on how long it can fly on a single-engine. To put it into actual time, a Boeing 787 Dreamliner is certified for ETOPS-330. This means that the plane can fly on routes that take it 330 minutes from the nearest suitable airport for landing. To put it more into perspective, the 787 can fly for five and a half hours on one engine. The Boeing 777 is also certified for ETOPS 330, while the popular Boeing 767 only gets a 180 minute (three hours) ETOPS certification.
As for Airbus and their modern twin-engine jets, the newish A330neo has a European Aviation Safety Agency (EASA) ETOPS rating of beyond 180 minutes and the option to increase this to ETOPS 285, which means the A330neo can fly 2,000 nautical miles on a single-engine. The ETOPS rating for the Airbus A350 is a massive 370 minute maximum diversion time. This means that the A350 can fly for six and a quarter hours on one engine.
Narrow-bodies will soon be flying over oceans
In the not too distant future, it is most likely that several airlines will start flying narrow-body aircraft like the Airbus A321LR on transatlantic routes as it has an ETOPS rating of 180 minutes flying time on one engine. While not generally used for ocean crossings, the Boeing 737-800 and MAX are certified with an ETOPS rating of 180 minutes, which means airlines like Southwest can now use them to fly from the United States mainland to Hawaii.
Should a plane have the misfortune of losing an engine, the pilots will take the aircraft down to a lower altitude and work the single functioning engine harder. They will then look for the nearest airport at which they can land and divert to it.
Have you ever been on a plane that has lost power in one engine? If so, please tell us about the experience in the comments.