Can Planes Fly with Only One Engine?
It’s the kind of thought that crosses even the most seasoned traveler’s mind:
What happens if one of the engines fails? Can a plane actually keep flying?
The short answer?
Yes, and not just for a few minutes, but for hours.
Modern commercial aircraft are engineered with redundancy, power, and safety protocols that make single-engine flying not only possible, but expected in certain emergency scenarios.
How Many Engines Do Planes Really Need?
Today’s most common commercial aircraft like the Airbus A320, Boeing 737, and Boeing 787 are powered by two engines.
But they’re not designed with the assumption that both engines will always work. Instead, they’re built so that one engine alone can keep the plane flying, climbing, and even landing safely if needed.
This design principle is called engine-out capability, and it’s required by aviation authorities before any aircraft is certified to carry passengers.
What Happens If an Engine Fails Mid-Flight?
When one engine fails, pilots follow a predefined checklist and take control of the situation using standard operating procedures.
Here’s what happens:
The aircraft levels off or begins a controlled descent if needed
Pilots assess the issue and notify air traffic control
The plane continues to fly on the remaining engine
If necessary, the crew diverts to the nearest suitable airport
In many cases, passengers don’t even notice the change in engine thrust
ETOPS: The Certification That Makes It All Possible
If you’ve ever flown over the ocean on a twin-engine aircraft, you might’ve heard of ETOPS (Extended-range Twin-engine Operational Performance Standards)
It’s a certification that allows twin-engine aircraft to fly long-haul routes over water, deserts, or polar regions — areas far from alternate airports.
Depending on the aircraft and its certification, ETOPS can allow up to 180, 240, or even 330 minutes of flight on just one engine. That means your plane can be five hours from the nearest airport and still meet all safety standards.