What are ‘evacuation slides’?

About Evacuation Slides:

• It is an inflatable slide which allows passengers to safely exit the flight during an emergency, especially when the flight door is high above the ground.
• There are four types of evacuation slides:
  • Inflatable slide: The inflatable slide helps passengers descend to the ground from an aircraft exit door. In case they cannot use the doors, they can try to reach either of the aircraft wings. From there, they can use the slide to reach the ground.
  • Inflatable slide/raft: It does the same job as the slide, but it can also be used as a life raft in case the aircraft has to land on water.
  • Inflatable exit ramp: The inflatable exit ramp is installed to help passengers move from certain overwing exits (or aircraft emergency exits) to the wings if that path looks better for reaching the ground.
  • Inflatable exit ramp/slide: The inflatable exit ramp/slide is there to assist in descending from an overwing exit or aeroplane wing to the ground. It is a combination ramp and wing-to-ground device.
• These are typically made from carbon fibres and a nylon material coated with urethane for fire resistance. Strong fibres are used to build these slides so that passengers are not able to tear them while descending.
• Slides are generally packed and installed within a cabin door or into an external fuselage compartment.
• They are inflated with the help of high-pressure gas carbon dioxide or nitrogen gas containers and ambient air through suction machines.
• What are the protocols for deploying evacuation slides?
  • An evacuation slide must be deployed when the distance between the ground and the flight exit door is six feet or more.
  • The European Union Aviation Safety Agency’s guidelines say that a slide should be automatically deployed, once the door is opened. The slide must be inflated between six and 10 seconds, depending on its location.
  • It should be properly deployable in all weather conditions — as cold as -40 degree Celsius and as hot as 71 degree Celsius.
  • The slide should be able to sustain a rainfall of up to one inch an hour and winds up to the speed of 46 km/hr which would be coming 45 degree angles around the aeroplane.