How Do Evacuation Slides Work?

You’ve all been familiar with the Evacuation Slides if you’ve flown before – either presented to you by the Flight Attendant’s safety briefing or the airline’s inflight safety video. But have you ever wondered about how they work and how they can save your life? Let’s take a look into the engineering behind this essential safety equipment!

Purpose

Evacuation Slides are installed on virtually all commercial aircraft (Boeing, Airbus, Bombardier) and also on many military aircraft as well. They serve an essential purpose in evacuating passengers, in a safe and controlled manner, in the event of a land or sea ditching. Given the height of most aircraft, most passengers will probably injure themselves if they’ve had to jump out of a burning aircraft to reach the ground. On the other hand, a water ditching would mean a higher risk of drowning and the aircraft sinking into the water. In that instance, the slide can be detached and used as a raft in which the passengers and crew can climb into, keeping them afloat until rescue arrives.

Placement & Deployment

These slides can be found neatly packed into a pocket at the bottom of the aircraft doors. On other aircraft, particularly the MD-80 and similar models, the tail-cone can be jettisoned and the escape slide can be deployed that way. If the door is armed correctly before leaving the gate, the slide will automatically deploy when the door is opened. Over-wing slides function the same way, with the slide’s conveniently designed to curve over and down the wings. According to FAA regulations, the slides need to inflate in less than 10 seconds and passengers evacuated in 90 seconds with half of the available exits!

Credit: docplayer.net

Inflation & Manufacturing

Slides inflate with an initial boost from a canister of compressed carbon dioxide and nitrogen. The canister provides only about one-third the volume needed to inflate the slides. The remaining volume is supplied by ambient air, channeled into the slides through aspirators. When fully inflated, the valves close so that no air escapes.

These slides are made of nylon and then coated with aluminium paint to offer some protection against fire. LED’s are also installed along the sides and centre-line of the slide for increased visibility. Workers laboriously fold and pack the slides at the manufacturing plant to fit into the fixture of the aircraft doors. And yes, quality control is crucial here. Repeated tests are executed to analyse the slide’s performance, durability, and timing of inflation.

Credit: LJS-aviation.com

These slides are just one of the aspects to appreciate about flying. So the next time you board a plane on your next flight, think about how much work went behind planning, manufacturing, designing, and testing these feats of engineering!


Sources:

Cover Photo Credit: EAMworldwide.com

https://www.airspacemag.com/flight-today/how-things-work-evacuation-slides-22196601/

https://eamworldwide.com/slides/

https://ljs-aviation.com/evacuation-slides/