Mayday, mayday, mayday: Engine failure in modern airliners

By definition, an engine failure at an airplane is a hazardous thing. Compared to a car, which you can stop alongside of the rode and you’re fine, you can’t just stop an airplane in mid-air and call for help. This means the pilot has to deal with the situation in-flight and still keeping situational awareness – flying the aircraft and avoiding physical contact to anything more solid than the air it flies in. This requires a big deal of training, and also is one of the many reasons why professional pilots generally are well-paid labourers.
Back to the engine failure. There are many reasons why an engine of a plane seizes duty:
In the golden days, when airliners had huge piston engines with propellers attached to, the most common reason was fatigue of material. Just imagine: 18 pistons per engine, moving back and forth several thousand times per minute, something’s got to brake sooner or later. Today’s jet engines only have rotating parts, therefore fatigue is not such a big issue anymore.
Another reason may be lack of fuel. Mostly this results out of miscalculation in the planning stage of the flight, although there reportedly are cases when fuel-leaks occurred in modern airplanes.
But the most common reason for engine failure at modern airliners is given to pilots by mother nature’s own creatures: Birds.
Let’s have a closer look at that case. This is a modern jet engine:

It’s a widely used CFM56 engine, attached to such planes as the Boeing 737 and some versions of the Airbus A32X series. This type of engine is called a ‘high bypass turbofan jet’. High bypass meaning, that the turbofan in front of the engine – the thing that’s visible if you look at the engine from the front, here colored light blue – leads most of the air alongside of the combustion area. The bypass air is being accelerated and then mixes with the air coming from the combustion area. In modern jet engines this bypass air produces up to 80% of the total thrust in flight. And when the bypass airflow mixes up with the hot air coming from the combustion part - red - it also reduces the noise of the engine.
Another very convenient thing the front fan does is acting as a centrifuge, when something gets sucked into the engine that’s not air. We’re basically talking about water (rain) and ice (hail). The CFM56 engines have been extensively tested on that, and so far no-one managed to extinguish the combustion fire inside the engine with water.
Birds are a different story: Some of them are big and heavy enough to make it into the combustion chamber, causing mayhem in there. Although the front fan works a bit like a food processor and slices the bird into little pieces, the engine still gets ripped apart and can explode. In the temperate climate zone birds don’t fly very high. So the most likely moment to ‘catch’ a bird with such an engine is during take-off and landing. The landing isn’t much of a problem: The aircraft is about to touch down soon anyway, and the engines don’t run at very high power. The take-off is the critical moment: The engines are running at full power – well almost, but that’s another story – and the aircraft might already be too fast to stop on the remaining runway: Beyond a certain speed (V1) the pilot has to take-off, no matter what.
The deal is: Bring the aircraft to a save flight-level, stabilize its condition, and then deal with the problem. But the pilot doesn’t face an impossible challenge: Engineers have been thinking about the problem already. And here’s the solution: Modern airliners are able to take-off and climb to a save flight-level even when loosing half of their thrust at V1 speed.
I’m sorry for this very long introduction, but I think it explains what’s happening exactly in this video: Bird-strike at Manchester airport. The engine explodes and the plane instantly looses 50% of its propulsion, yet still the pilots react very calmly to it. This is not a fake, it’s been filmed with a video camera connected to an radio-scanner. Enjoy – and remember next time you sit in an airliner: Your pilots are highly trained professionals, and the equipment is extremely reliable and redundant.