Airplane coffee has a bad reputation. Really bad. In addition to being notoriously watery and bland, there's an endless swirl of rumors percolating about the quality of the water used to brew your standard pot of airplane coffee. Even the cleanliness of the coffee pot has come into question.
In an effort to get to the bottom of this murky mystery, we spoke to flight crew members and reviewed hard data. And we've also consumed more than a few cups of coffee on flights. The results? Frankly, a little mixed.
What the data says
In 2015, a commonly-cited paper titled "Bacteria that Travel: The Quality of Aircraft Water" in the International Journal of Environmental Research and Public Health found that 37 species of bacteria could be identified in potable on-board water. Most were natural aquatic bacteria, but two were not.
"However," the paper concluded, "the bacteria represented do not fall into the dangerous infectious microorganism categories ... nevertheless, the isolated bacteria from this study have the potential to cause illness in certain sectors of the traveling population, including immunocompromised individuals."
The study also found that "long-haul flights were found to be significantly poorer in terms of microbial quality than short-haul flights" — likely as a result of water tanks being filled from local municipal sources.
And just last month, an airline water study by both the Hunter College NYC Food Policy Center at the City University of New York and DietDetective.com reported that many airlines continue to violate the federal government's Aircraft Drinking Water Rule (ADWR).
Though violations among major airlines have decreased 69% since the ADWR was implemented in 2011, the study said the change "might reflect a lack of enforcement," as the EPA hasn't been issuing many penalties.
And water samples continue to test positive for E. coli and coliform bacteria. JetBlue and Spirit — the major airlines that performed worst in the study — had a high number of ADWR violations and a really unsettling number of water samples test positive for E. coli and coliform.
Does this mean you should immediately stop consuming airplane water (including the inflight coffee and tea)? According to this study, yes. "To be extra safe," the study concludes, travelers should not drink coffee or tea onboard, and "never drink any water onboard that isn't in a sealed bottle." After using the bathroom, the study also suggests travelers use hand-sanitizer.
What flight attendants say
Jay Robert (also known as "A Fly Guy" and creator of A Fly Guy's Cabin Crew Lounge) cited those same published findings from 2015 when he told The Points Guy the "'dirty airplane water' rumor is indeed a fact."
"I have even spoken to other crew who have become very sick after drinking hot beverages from an aircraft."
"But it's not just about the aircraft's tanks or pipes," he said. "The flight you are on from London or Los Angeles might have just returned from an underdeveloped country that wouldn't have the same high sanitation levels as the country you are in now."
And, as the "Bacteria that Travel" paper noted, airplane water is typically just surface or ground water. (A former line service technician confirmed with TPG, "They're not dumping gallons of Fiji water into those tanks.")
However, flight attendant and creator of Jetlagged Comic Kelly Kincaid told TPG that she's been flying for more than a decade, and drinks the coffee and tea all day long.
"I've never had any problems," she said. Kincaid added that her husband, also a flight attendant, "drinks about a pot of coffee a day from the plane" and is, thankfully, still standing.
"Now, from my understanding, the water does undergo some chemical cleaning, which can have a slight smell to it," Kincaid said. "I do not drink [the water] when I smell it, not because I think it's unsafe, but because I simply do not like the smell. It eventually wears off and then the water tastes fine."
In 2018, TPG contributor and flight attendant Carrie A. Trey said flight crew members "absolutely drink the coffee."
"In fact," Trey added, "when you have one crew coming in, one of the first things you do is put on a fresh pot of coffee for the pilots and crew."
And flight attendant Amanda Pleva told TPG that while airplane water is "rarely great," it's definitely not worse than municipal water she's consumed in crappy apartments. And it doesn't stop her from drinking the coffee and tea, either.
"I always drink the airplane coffee and tea," Pleva said. She specifically prefers the espresso from first class, but said the tea tastes great — so she blames the coffee pots for the "gross taste" of coffee.
Robert said that even though the airline he works with has young aircraft and "very high cleanliness standards," he simply doesn't trust the water loaded into those systems: "I go to great lengths to avoid it."
About those coffee pots
"Honestly, I am often amazed when a coffee pot is cleaned, " Pleva said. "I've actually noticed an improvement lately, but oftentimes they're neglected."
Kincaid, on the other hand, said travelers shouldn't worry about the cleanliness of the coffee pot — "coffee pots are regularly cleaned and restocked."
And Robert agreed this is the one part of the coffee-brewing process you really don't need to worry about. "At the airline I work for, the pots are removed and replaced with clean ones after every aircraft completes a round-trip and arrives back at base ... It's part of our landing duties to clean the pots!"
What you can do
If you're deeply concerned about the quality of the airplane coffee, tea or water — particularly if you're flying from a country where the local water may be troublesome (or the aircraft is coming in from such a place), be sure to buy bottles of water before boarding your flight.
But if what you want is a piping hot cup of Joe before landing, there's not much you can do except accept what's offered, or wait until you land.
"We cannot heat up other passengers' water," Kincaid said. "For one, that is also a health concern and the other is, we have no way of doing this. Airplanes do not have microwaves."
If people are concerned, she said, "bring your own coffee or tea [from] an airport café."
Travelers can also improve the odds of having a clean cup of coffee by flying early in the morning, according to Kincaid.
"The very first flights of the day are restocked with fresh and clean coffee pots. If you are getting on an afternoon flight and notice the coffee pot looks a little 'used' that's because the previous flight used them."
She did say, however, that the washing and restocking could take longer than a day, depending on flight schedules.
Another pro tip? "I actually keep a flask that I get filled with hot water once I'm through security. I use that hot water with my nanopresso to make my own coffee," Robert said.
If you don't find any of this reassuring, consider this: TPG's own JT Genter has flown 270,946 miles in the last year — and he's consumed an awful lot of airplane coffee on those flights.
"I eat street meat. I drink the coffee on planes. I'll try any food once," he said. "I see it as keeping my immune system active."
