The Fly-Bag is made from multiple layers of fabrics and composites that have high strength and impact, and heat resistance. The fabrics include Aramid, a heat-resistant and strong synthetic fiber used in the aerospace industry, as well as in ballistic body armor.
The lining’s flexibility increases its resilience in containing an explosion and any blast fragments, said Dr. Andrew Tyas, of the Department of Civil and Structural Engineering, who is leading the research at the University of Sheffield. The Fly-Bag, he added, acts as a pliable membrane instead of a rigid-walled container that could shatter on impact.
Laboratory-based blast testing had successfully proved that the Fly-Bag prototypes could withstand explosions. But it was real-life controlled explosions in the luggage hold of a Boeing 747 and an Airbus 321 that put the technology to the ultimate test.
One controlled explosion was conducted in a luggage hold not lined with the Fly-Bag. The blast ripped a gaping hole in the fuselage that could have proved fatal if the plane was traveling at altitude. For the second test the bomb was placed in a suitcase and then in a luggage hold lined with the Fly-Bag. Slow motion camera footage of the bag at the moment of detonation showed it expands and contracts but does not tear. The structural integrity of the fuselage was maintained.
Leading British security consultant Matthew Finn said the Fly-Bag could be an ideal fail-safe in the event that somebody is able to smuggle an explosive device aboard an aircraft.
“The risk that we always have in aviation security is can someone get something on board an aircraft. So a lot of our time and attention has been focused on mitigating the risk of people getting things on an aircraft. What the Fly-Bag does is it actually accepts that there maybe an instance where somebody is successful in getting something on board an aircraft. And therefore, the next question becomes how can we mitigate the effect of an explosive device detonating at altitude in an aircraft,” he said.
The need for some way of mitigating an explosive device on an aircraft was heightened on October 31 when a bomb ripped apart a Russian passenger jet over Egypt, killing all 224 people on board. Islamic State claimed they were responsible for the attack, releasing a photograph of a Schweppes soft drink can it said was used to make an improvised bomb that brought down the Russian airliner.
Explosives experts said it was feasible the device shown in the photo could bring down a plane, depending on where it was located and the density of explosives in the soft drink can. The most vulnerable locations include the fuel line, the cockpit or anywhere close to the fuselage skin.
The attack drew parallels with the bombing of Pan Am Flight 103 by Libyan nationals over the Scottish town of Lockerbie in 1988. An investigation showed a palm-sized explosive in a cassette recorder in a bag in the luggage hold had ripped a 50 centimeter hole in the fuselage and decompression caused the plane to break up in mid-air.
Finn, managing director for security consultants Augmentiq, which offers advice to enhance security at airports, ports and international borders, said the Fly-Bag deserves to be seriously considered as a way to mitigate such explosives on aircraft.
“I think it has the capacity to transform how we look at hold baggage. We’ve spent a lot of time thinking about the reconciliation of passengers and their bags; since 1988, since the Lockerbie Disaster, that’s been a big focus of the airline industry. What the Fly-Bag does is look to those situations where there may be the device on board and how do we contain that. I think it’s a really interesting development and I’d like to see it deployed more widely” he said.
The Fly-Bag is being developed by a European consortium including Blastech, a spin out company from the University of Sheffield, as well as partners from Greece, Spain, Italy, Germany, Sweden and the Netherlands.