As More Devices Board Planes, Travelers Are Playing with Fire | Hacker News Reader

As More Devices Board Planes, Travelers Are Playing with Fire

nytimes.com

46 pointskawera41 comments

RC enthusiasts use LiPo batteries, which can cause a lot of damage if mishandled and damaged, you can see a video here where a famous quadcopter pilot shows how many batteries he carries for a day of flying [0].

These batteries go into your carry-on luggage and needs to be protected from damage and short circuit.

Some info on why batteries shouldn't be in the cargo hold "Halon 1301, the suppression agent found in Class C cargo compartments, is ineffective in controlling a lithium metal cell fire." [1]

Here is the FAA requirements:

- LiPo batteries installed in a device are ok in either checked or carry-on luggage.

- An unlimited number of spare (uninstalled) LiPo batteries with a rating of up to 100 WHr may be carried, but only in carry-on baggage.

- With airline approval, up to 2 LiPo batteries with ratings between 100 and 160 WHr may be carried, but only in carry-on luggage.

- LiPo batteries larger than 160 WHr are not allowed.

It seems really strange you can travel with these things, I can't imagine the damage that will happen if a bag of batteries happens to blow up.

[0] https://www.youtube.com/watch?v=vCtneglrE8I&t=278

[1] http://www.faa.gov/other_visit/aviation_industry/airline_ope...

Just FYI, LiPo batteries aren't lithium-metal, they are lithium-ion. They have different failure mechanisms.

The fire in a LiPo is cause by the electrolyte being too hot due to an internal short-circuit and thus igniting, not because lithium is reacting with water as a lithium-metal battery does. LiPo is thus safer than lithium-metal, since a leak to the environment doesn't necessarily result in a fire. Even safer are LiFePO4, which are as safe as NiMh, although their energy density is slightly lower than LiPo.

Lithium-metal is mostly used for coin cells, eg for watches.

I have about three dozen LiPo packs of various sizes, cell counts and energy content for my RC planes and helicopters. I've had many swell-up. We took the opportunity to safely abuse them and see what a fireball failure looks like. Scary and awesome at the same time.

All my LiPo's are kept in fiberglass fireproof bags. These bags are kept in a dedicated metal toolbox with a set of exhaust holes drilled. The toolbox sits on a set of bricks laid flat on top of a table. Also, there's nothing flammable on top of the toolbox.

The point is to contain the heat and fireball while allowing pressure and smoke to release. The system hasn't been tested yet (haven't had a pack self ignite, ever) yet I feel reasonably confident that it will do a good job of protecting my house.

The Aviation Herald lists a few incidences with batteries:

http://avherald.com/h?search_term=batter&opt=0&dosearch=1&se...

(as I mentioned in the thread "FAA Urges Passengers to Not Use Samsung Galaxy Note 7 on Planes", https://news.ycombinator.com/item?id=12459335 )

Back in college I worked as a iOS and Mac technician at a Apple Store Genius Bar. First couple of months working there I noticed we had a yellow safe under our bench. My supervisors informed me the safe was for swollen batteries, hot iPhones or anything that could explode or catch fire.

Needless to say I only ever experienced one dangerously swollen battery on a MacBook. Food for thought.

I recently bought a Macbook Air that had a battery so swollen that the entire laptop was convex and the lit couldn't even close. I'm talking a two inch bulge.

What's amazing is that nothing broke and changing the battery allowed the aluminium to bend back and you can't even tell that the laptop looked like that.

The person that had it before me was actually using the laptop with the swollen battery until it got so bad some of the keys were getting pressed from under. That person could have easily used the laptop in question in a plane.

What about a laptop sized ashtray / metal bin with a loose lid and some small opening for a fire extinguisher? In the first two minutes it should already be noticed and still be scoopable. Well, unless it's still in a bag. How well do fire extinguishing blankets work in the cluttered cabin? What is currently the protocol?

If it ain't broke, don't fix it; printed novels don't contain lithium ion batteries.

Read on a flight, save a life!

or to be more modest: a capacity limit so you can take your phone, but not your tablet.

And, yet, a number of airlines (such as United) are introducing entertainment systems whereby they stream content to your own device.

More fundamentally, do you suggest that people travel without tablets or laptops? Never going to happen. And it's better to have the batteries in the cabin than in the hold.

it's better to have the batteries in the cabin than in the hold.

Why? Seems like you could have more effective fire-extinguishing methods in the hold (replacing oxygen with an inert gas, for example).

I don't think the hold is pressurised, and so there would be very little oxygen there.

Where do pet crates go? I think it might be.

Cargo holds are typically pressurized. Pressurizing forward of the aft pressure bulkhead doesn't really add significantly to the structural requirements of an aircraft as I understand it. Furthermore (in addition to pets) you'd probably see lots of leaking and otherwise damaged contents of luggage/cargo if the hold were unpressurized.

More than that, the most efficient pressure vessel is a circular section (tension only). Making the floor of the passenger cabin the pressure vessel would be very heavy, as it would have to carry the load in bending.

Of course it is pressurized. If it were not shampoo and toothpaste would leak out of their containers.

Presumably the reaction to an in-cabin fire will be quicker than to that of a fire in the hold.

Do these batteries provide their own oxidizer somehow (in that would flooding the hold with CO2 or something actually extinguish one on fire)?

I don't know how fire protection currently is within an airplane hold but surely this is a solveable problem. Maybe airlines are asking that people not put these batteries in the hold is because fire protection systems haven't yet been adapted to this risk.

Presumably the reaction to an in-cabin fire will be quicker than to that of a fire in the hold.

A couple of decades ago I could see that, but nowadays? Surely installing an array of heat and smoke sensors wouldn't be that expensive?

No it's probably not anything new but when you muck about with commercial airplanes things get expensive and take a lot of time (regulatory issues). It's one thing to modify something with your car, for example, but when you change something about a commercial airliner it's not so simple.

> Do these batteries provide their own oxidizer somehow

Yes - the metal oxides in one of the electrodes decompose at high temperatures. CO2 will stop it setting other things on fire but the battery will continue to burn like a thermite reaction until it runs out of fuel.

Ah...you say it's like thermite...could one of these melt its way completely through the plane fuselage?

You can see my comments about Halon 1301 here: https://news.ycombinator.com/item?id=12478330

You could put all batteries in protective bags if really needed.

http://alexnld.com/wp-content/uploads/2015/02/SKU154973-2.jp...

All batteries have protection against overheating and fire. The chance of a battery becoming on fire is very very small.

Printed novels dry out my fingers, are exceedingly heavy (even one weighs twice as much as 1000+ ebooks, and we're talking about flying which has weight limits), inaccessible for many readers (no audio narration, large-print editions have to be bought separately and are even heavier), hard to read in the dark...

I don't think that's a fair test if that photo is accurate. Those seats are not setup in a normal "cattle car" configuration. That looks like a luxurious 40+ inches of seat pitch compared to the normal 30.

I would expect there to be the potential for a much faster spreading fire with a realistic seating configuration.

In all probability, there are stringent requirements for flame spread, smoke developed, and the creation of toxic gasses for airline seats similar to those discussed for passenger trains here:

http://www.compositesworld.com/articles/passenger-safety-fla...

The NYT article is (slightly) out of date - the carrier I was flying with last night made a point of stating the Samsung Galaxy Note 7 could not be used at any time during the flight.

We received the same warning on both outbound and return legs of an Aer Lingus flight from IAD to EDI. Not sure how they would ever enforce it, beyond the honor system, or expecting other passengers to notice and report misuse.

I'll just leave this here:

https://youtu.be/eHooBjxmoXQ

I think the biggest elephant in the room is that you're allowed to bring (as hand carry) 3 liters of liquid fuel in glass containers on international flights... as long as you purchased said flammable liquid in a duty free store

Can you purchase overproof liquor in the duty free store?

I looked for 151 but couldn't find it at the airport duty free store. I'm sure it's available at external duty free stores though :(

In the US, at least, you aren't allowed to carry any liquid (besides non-essential medications, baby formula) in containers larger than 3oz through security regardless of if its duty free.

I had no idea that duty free stores existed outside of airports, to be honest.

Depending on what you mean by overproof the answer is yes sometimes in some places.

Soft definition of overproof - "Any alcohol that can be easily ignited and turned into an violent explosive."

Don't they sort of "gate check" duty free purchases and you pick them up at the destination?

Not that I'm aware. If you've seen duty free purchases at the gate it's probably because they've been delivered from duty free for the purchasers to pick up and take on the plane. (Because, though they're usually no great deal, duty free is only for purchases being taken out of the country.)

No, sort of opposite. You pick them up at the departing gate and carry them aboard. I'm guessing they do that to make it more likely you're taking them on an international flight and not buying stuff for someone else on a different flight.

Ah, I never bought anything duty free, but I've seen them set aside at the gates. Guess I assumed it was to be picked up at arrival. Thanks for the info.

Have you ever tried to light 80 proof alcohol?

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