A new invention is halting fires on board planes and saving airline companies a fortune. The AvSax fire containment bag is used to deal with fires in electronic equipment on aircraft and it has already been used 20 times this year.
Such incidents are rarely publicised but a fire in a device could emit toxic smoke and potentially the battery may even explode, causing severe damage to the aircraft and putting lives at risk.
There are many cases where such fires have caused planes to be diverted as an emergency and the average cost of that in the US is $400,000.
The fires are caused by lithium-ion batteries inside electronic devices ranging from mobile phones to laptops.
AvSax are now carried on all 1,334 Delta Air Lines aircraft worldwide along with other major carriers.
A recent estimate revealed that aircraft carrying just 100 passengers could have around 500 lithium batteries on board when you tot up all the laptops, cameras, e-readers, tablets and mobile phones that need them. There is always a possibility that poor quality or damaged batteries can overheat, causing them to go into what is known as thermal runaway which could lead to the device catching fire
When one cell in a battery overheats it can produce enough heat - up to 900°C (1,652°F) - to cause adjacent cells to overheat. This can cause a lithium battery fire to flare repeatedly.
Incidents of thermal runaway are on the rise.
Federal Aviation Administration data in the US reveals that in just nine years battery-powered devices were involved in 113 incidents causing 'smoke, fire, extreme heat or explosion' on passenger and cargo planes.
Cargo planes have been a serious concern. Battery shipments were implicated - but not proven as the cause - in crashes of an Asiana Airlines flight near South Korea in 2011, a UPS flight in the United Arab Emirates in 2010 and a UPS flight in Philadelphia in 2006. Federal Aviation Administration testing later found that halon gas used to suppress fires on planes doesn't work well on batteries in thermal runaway as they can reach such high temperatures.
AvSax Managing Director, Richard Bailey said: “AvSax is the result of many years of development, drawing on experience from the production of an alternative sandbag we invented called a BlastSax designed for the military to reduce the impact of small improvised explosive devices.
The danger is that with so many poor quality and fake batteries around there is no doubt that incidents will continue to happen. We never thought at the start of the year that AvSax would be deployed 20 times on aircraft in just seven months.”
In mid January an AvSax was deployed during a mobile phone fire scare on a Delta Air Lines flight to Hawaii.
Airport officials say a passenger on the flight from Fukuoka to Honolulu dropped his iPhone 7 and when he tried to shift his seat it crushed the phone and battery. His fingers were singed and there was smoke and the smell of burning plastic in the cabin.
The crew retrieved the phone and put it in an AvSax fire containment bag to prevent any other danger. The plane landed safely.
So how do AvSax work?
If an electronic device starts to seriously overheat or emit smoke the cabin crew will pour at least two litres of water into an AvSax and then drop the burning device into the bag, adding additional water as required. The water activates the polymer gel inside the bag causing it to expand around the device. Should the device keep on venting then the AvSax is tough enough to absorb the force.
The AvSax cools the batteries in the device, reducing the likelihood of the battery catching fire but if it does go into thermal runaway it is all contained within the bag.
The water is absorbed into the internal lining of the bag so the device is dry when it is removed.