It's on most commercial aircraft and large aircraft with turbofan engines... Is there a specific name for it? Does it serve any other functions apart from attaching to the wing and feeding the engine the essentials? Has there been any aviation incidents that involved something malfunctioning or breaking inside of it? Or some other interesting things about it? Just out of curiosity! Thanks! :)

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3 Answers 3


It's a hard-point called an "engine pylon".

And yes, some designs use specific points designed to fail if there is excessive force, allowing the engine to separate from the aircraft without ripping the entire wing apart which would obviously be a catastrophic event. It has happened on a few occasions.

The above image is from the Wikipedia page on the American Airlines 191 accident, where, due to a faulty maintenance practice of using forklifts for removing and reattaching the engine/pylon assembly, the aft bolts were damaged. The pylon eventually failed, allowing the engine and pylon to push up and over, separating from the wing.

Other examples include China Airlines 258 and El Al 1862.

  • 2
    $\begingroup$ Note: in flight 191, the engine and pylon did successfully separate from the wing but damaged the flaps mechanism, causing plane to bank then crash, killing all on board. $\endgroup$
    – fjw
    Sep 8, 2014 at 0:05
  • 2
    $\begingroup$ China Airlines 258 and El Al 1862 also killed all on board. Has there ever been an incident where the engine separated from the wing during flight but everyone survived? $\endgroup$
    – fjw
    Sep 8, 2014 at 0:07
  • $\begingroup$ @fjw United Airlines 232 managed to make it to an airport to land, but crashed right before touchdown. $\endgroup$
    – Cole Tobin
    Sep 8, 2014 at 6:19
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    $\begingroup$ Am I the only person who looked at that image and immediately thought "Starship Enterprise"? $\endgroup$
    – Bob Tway
    Sep 8, 2014 at 12:01
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    $\begingroup$ @Keegan the engine separation was successful in the sense that the aircraft kept flying. Unfortunately due other damage it was unable to remain controllable at low speeds iirc. $\endgroup$
    – falstro
    Sep 19, 2014 at 16:52

It's a pylon and indeed just hold up the engine and connects it to the craft. They are designed so that excessive force will cleanly separate the engine without damaging the wing.

American airlines flight 191 had the pylon fail in midair due to mishandling of the engine during maintenance.

2 engines separated in El Al flight 1862; in this case the inboard engine separated cleanly but then slammed into the outboard engine where it did damage the wing. The same thing happened a year earlier in China Airlines flight 358.


This part is called the "pylon" or "strut" for the engine. It holds the engine on the wing, provides a path for all of the engine systems to connect, and includes the aerodynamic fairing to cover it all. The strut is designed to prevent a fire in the engine area from spreading to the wing. Mounting the engine below and forward of the wing leading edge provides some advantages over other options.

Once the strut is installed on the wing, it is intended to be permanently attached there. As shown in falstro's picture, the engine mounts are installed on the engine, and allow engines to be installed and removed as needed. When no engines are installed, a weight is suspended from the strut to balance the aircraft and prevent the plane from tipping backwards.

There are differences in design between manufacturers. Boeing struts are designed to break away from the wing under extreme loads. The strut attaches to the wing using fuse pins, which will fail at a specific loading, lower than the strength of the wing. This prevents the wing from breaking under the load, which could cause the fuel tanks to break open and start a fire. Examples of engines breaking away as designed are the Asiana 214 and Lion Air 904 incidents last year.

Airbus struts are designed to remain attached to the wing. This actually allows the structure to be less complex, and Airbus struts tend to be noticeably more narrow than comparable Boeing struts. Other methods are used to maintain safety in a crash, such as keeping the area directly above the engine as a "dry bay", which is not used to store fuel.

Here is an Airbus patent for a strut design using composite panels, which describes the strut.

As mentioned by falstro, there are multiple incidents where the structure in the pylon has failed, resulting in the engine coming off of the plane in flight. There have been both design and maintenance causes for such incidents, and both design and maintenance changes have been made to address those issues.


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