How do you stress test an airplane?
Well, you don't make it run on a treadmill, that's for sure.
Fatigue testing aircraft is important in determining the structural integrity and quality of the airframe before they actually take flight (you know, with people travelling in them). This simulation testing allows the engineers to address any problems or concerns the plane could undergo during a standard flight.
There are two different methods to stress testing a plane: static testing and fatigue testing. Static testing is when engineers push the plane to extremes to see how strong the frame is, while fatigue testing (as demonstrated in the video above) simulates and demonstrates how the structural integrity of the plane will hold up over time.
In the case of this Boeing 787 Dreamliner, engineers put the aircraft in a specially designed test ring where more than 100 mechanical devices were connected to various parts of the plane. Through these devices, the engineers at Boeing are able to apply loads to the aircraft: pushing, pulling, and twisting the surfaces repeatedly simulates the impacts of real-world flying conditions. Sometimes these types of simulations (which can number in the tens of thousands of simulated flights) can age a plane by years in only a matter of months, which perhaps only further reinforces the notion that the forces of time are merely an illusion.
So the next time you catch a flight on a Boeing aircraft (or any commercial jet, really), take some comfort in knowing that before you landed yourself that spot in economy class, somewhere an airframe very much like the one you're travelling in was put through the rigors and passed all its tests. So sit back, relax, and try not to think about how little leg room you have. Because even though your patience may not hold up for the flight, the airframe will.