It's fair to say that probably every person who has ever travelled on a plane has imagined what they would do if an emergency actually unfolded during their flight.
You might picture yourself heroically helping people put on their oxygen masks, helping a panicked mother with her newborn baby or getting into the brace position - even though it's not exactly the most delightful daydream.
But I'd put good money on the fact that the large majority of people would never, ever picture themselves evacuating an aircraft in anything but a neon life jacket which they've grabbed from underneath their seat.
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It's one of the more memorable aspects of the pre-flight safety demonstration, especially as being able to efficiently grab it could mean the difference in life or death.
It's got a whistle, light and can only be inflated once you have left the plane, so all in all life jackets are a pretty handy bit of kit which can have a huge impact during a dangerous incident.
So you can imagine the panic passengers might feel when everything they ever knew about safety in the skies is chucked out of window when travelling with certain airlines.
Some travel firms offer holidaymakers a bizarre alternative instead of life vests.
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Typically seen on smaller planes or short flights, these strange replacements will probably give the more anxious flyers quite the shock when they see what they are supposed to rely on a buoyant in a large body of water.
Instead of strapping on a life jacket, a range of airlines offer passengers 'flotation seat cushions' instead.
You know that thing your sitting on? Yeah, that doubles as a life preserver as well as a place to park your arse.
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As you can imagine, the safety card which illustrates how to use your seat to stop yourself from drowning is pretty comical, as far as cartoon emergency reenactments go.
One example, which was recently discovered while flying with an airline in Kenya, shows a plane crashing into water before a passenger peels off their seat cushion and safely navigates the sea with it while clinging onto the straps.
But unlike chucking on a life jacket, using a flotation seat device can't help keep a person afloat or face up when they are unconscious, as it requires the user to maintain control of it.
According to a European Technical Standard Order, published by the European Aviation Safety Agency, there are a range of items onboard which can also act as floatation devices.
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It states: "Seat cushions, head rests, arm rests, pillows, or similar aircraft equipment are eligible as flotation devices under this standard provided they fulfil minimum requirements for safety and performance.
"Compression through extended service use, perspiration and periodic cleaning must not reduce the buoyancy characteristics of these devices below the minimum level prescribed in this standard," it explains.
Although this sounds bonkers to a lot of people, it makes perfect sense to airlines.
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It is understood that they sometimes snub life jackets in favour of the flotation seat cushions to save weight, fuel and therefore money.
Airlines such as Air Canada's regional carrier Jazz previously said that they are abiding by government regulations which allow firms to use floatation devices instead of life vests, provided the planes remain within 50 nautical miles of shore.
Spokeswoman Manon Stuart previously told NBC: "The nature of our operations doesn't require that we carry both."
The average weight of a commercial-style life vest was roughly half a kilogram, which would mean Jazz would be around 25 kilograms lighter by removing them from 50 seats and instead using flotation seat cushions.
US safety professional and airline safety advocate Woody French also told the publication in 2008: "A lot of these airlines say 'Well, our passengers are our main concern'. That's a bit of a misnomer. We're a distant second. Profits are the first."
Olivia Burke