These Explosions Show Why the FAA Doesn’t Want Laptops in Luggage

Videos of the air regulator's experiments show how violent a battery fire can be.

Stop me if you've heard this one before. The US government wants a "laptop ban" on planes.

But this time, it's to prevent fliers from putting large electronics, like laptops, into their checked luggage. This seems like an about-face. Earlier this year, a chaotically implemented ban did the exact opposite, demanding passengers on flights from certain Middle Eastern and African countries pack tablets, DVD players, and laptops into their suitcases, to travel in the belly of the plane. Department of Homeland Security officials worried terrorists would disguise bombs as batteries inside these larger electronic gizmos.

The department lifted that laptop ban in June, announcing more rigorous security screening instead. But the temporary increase in large electronics in the hold left the Federal Aviation Administration, which oversees America's flying industry, with some questions: Is it safe to stow electronics—especially those with lithium-ion batteries—in cargo holds?

It was time for the FAA to blow some stuff up. You know—science. The agency ran a series of experiments, placing laptops inside typical suitcases next to your standard flammable toiletries: nail polish remover, hand sanitizer, and most explosively, an aerosol can of dry shampoo. You can see the results in the video above. (Watch with caution if you're a nervous flier.)

For these tests, researchers from the FAA’s Fire Safety Branch attached heaters to the batteries of their laptops, to force the li-ion cells into a state of "thermal runaway"—where they keep getting hotter and hotter. This can happen in the wild if a battery is damaged, or just poorly manufactured, and spark a blaze.

The resulting fires and explosions were large enough for the FAA to warn there’s a risk they could overwhelm the on-board fire suppression systems of planes, which flood the hold with inert halon gas. And if shrapnel from the explosion punctures the skin of the plane, all the halon can escape, leaving the blaze to burn unchecked.

In separate tests, the FAA also experimented with a galley cart, which airlines might use to store large numbers of in-flight-entertainment tablets together. If a device there catches fire and spreads, the resulting bang is dramatic, and potentially deadly.

The FAA’s recommended ban is being debated by a Dangerous Goods Panel at an International Civil Aviation Organization meeting in Montreal, Canada, this week. If there’s agreement, ICAO, which is part of the UN, could adopt the ban, which will likely be announced in January 2018 and implemented a year later.

In summation: A ban may have lead to an opposite ban. But safety comes first. And this time, if the international flying authorities decide you can't put your electronics in your checked luggage anymore, you should have plenty of warning. In the confusing interim, there's always a paperback.

Up in the air