Wings are pretty vital to an airplane. Engines, flight instruments, landing gear, yeah, these are all things you definitely want to be sure are mechanically sound before you find yourself hurtling at 500 miles an hour six miles above the surface of the Earth. Yet even the most devoted caffeine addict would probably rather take off on time than wait three hours for the plane’s coffee maker to get fixed — so what’s the deal when you have to camp out on the tarmac because the plane can’t make you a cup o’ joe?

That’s what the New York times recently looked into. And the answer, in short, is: because airplanes are really complicated.

The coffee machine on a commercial airliner isn’t just some plug-and-play drip pot like a consumer machine, or even like a ground-based industrial-strength one. Airplanes are their own closed systems, in flight — the power, the water, and everything else, for every machine on board, is connected.

So if the coffee machine won’t start, flight crew might have a bigger problem than just the absence of java on their hands.

FAA regulations require coffee makers on-board aircraft to have a host of safety features built in, to make sure that brewing you a hot cuppa doesn’t, y’know, light the plane on fire. That means if a machine is misfiring, a maintenance crew needs to give it a thorough once-over to make sure there’s no problem with the electrical system. They’ve got to check the coffee maker’s circuit breakers and insulation, as well as the circuitry that connects to it.

If the power’s fine, the problem might be the water — its own special, complicated system. Or the problem might be one of the latches or hooks that holds it in place. Or maybe the problem is clogged plumbing. Or a hundred other small, incredibly fiddly, precise things.

The plane can take off without a working coffee maker, of course, in the event that technicians decide it’s not a hazard but can’t solve the problem fast. But that makes customers — who get very little for free on-board on most airlines, and might cherish that coffee — testy, and they complain.

According to the NYT, the coffee maker problem is a big focus for American Airlines (which now includes the former US Airways fleet). The airline’s chief of operations is focused on fixing small issues that lead to big delays, and the coffee makers are on his list.

“One delay at the beginning of the day can impact hundreds, if not thousands, of passengers and their belongings,” he told the NYT. “It’s not only the most customer friendly, it’s also the most financially sound way to run an airline.”

The Times also checked in with Delta and United, the other remaining large legacy carriers. A United spokesman told the paper that although sometimes delays due to coffee machines do happen, “it’s not a prevalent cause.”

Coffee, as simple as it seems, is a surprisingly involved and complex piece of the modern air travel system. Back in 2012, the problems integrating coffee supplies and coffee machine specs became emblematic of the challenges United and Continental faced in their massive merger.

For Want of a Working Coffeepot, Your Flight Is Delayed [New York Times]

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