As I’ve mentioned before, I occasionally deliver airplanes cross-country to their new owners. I traveled to the PNW via airlines last week to fetch a Cessna back to DFW. The 20-hour ride home in the little plane was uneventful, but the same cannot be said for the 4-hour airline flight.
The plane was an almost full Airbus 319. The flight itself was very smooth, but about 2 hours into it, I started hearing people get sick. Not like mildly airsick, but violently ill, heaving your guts out, like a really bad hangover. This began to appear behind me, and I counted 2-3 people* (in separate areas) in near distress. This continued sporadically for a while, and then a man in the forward area collapsed unconscious. The cabin crew began making requests for any doctors or nurses to ID themselves. A few minutes later, a lady walking to the bathroom collapsed beside my seat, causing the remaining cabin crew to hurry to her aid. She was unconscious as well. After laying her out in the aisle, the nurses and cabin crew began checking vitals, and administering oxygen. Before they could get her recovered and upright, another person keeled over (one row ahead) and was unconscious as well.
At this point we have 3 unconscious, 3 very ill, and the nurses and cabin crew are racing madly about trying to care for them. I and an across-aisle “seatmate” were put to use holding legs aloft (nurse said to raise them) in all this excitement. I later heard 2 of the people describe their ordeal as feeling suddenly very hot, and then passing out.
Upon arrival, paramedics boarded the plane and helped the stricken out to the terminal. Most seemed to have recovered by the time we landed, and seemed to be almost OK and walking under their own power by the time we collected our luggage.
So… to the medical and/or airplane systems experts here: What could possibly have caused this? Was it just a random unlikely event? Something in the plane’s pressurization system? FWIW: There was no food service on the flight.
The only similar thing I’ve ever experienced was a flight that hit a repetitive turbulence, like a car hitting a small but sharp speed bump every five or six seconds. Everyone rode it out for a while, then was hit by a mass upset, which cascaded from the earliest victims to others. (Oddly enough, it didn’t affect me, even though I have a truly weak stomach about some things, the #1 being the word, sound or smell of vomiting.)
Is it possible that there was some kind of low-frequency turbulence that gave everyone the queasies, followed by something of a panic attack? (Air travel is certainly tense enough these days that many would be susceptible to such things.)
Mass hysteria? Some people are primed to expect problems on airplanes, and seeing someone fall ill could cause them to unconsciously copy that behaviour, up to and including fainting and sweating. It’s a bizarre phenomenon, but that could explain things.
Alternatively, I suppose it’s possible that fuel smells (that no one else noticed?) from bleed air may have entered the air conditioning system, causing people with sensitive noses and fragile stomachs to react. Pressurization problems seem unlikely, again, given as only a couple of people were affected, and I think the flight crew would have noticed a cabin overpressure.
Maybe these people all ate the same thing at an airport restaurant?
I don’t have anything to add to this thread except to say that I’m someone who’s already afraid of flying and gets motion-sick too easily, and this thread scares the hell out of me.
UC Berkeley tested the ozone levels on 76 international and domestic flights. Four domestic flights showed very high levels of ozone.
Air quality was best on overseas flights, which are required to have devices to filter the ozone out of the air - U.S. domestic flights are not. And even on flights with moderate ozone levels, researchers found that the pollutant actually reacts with the natural oils in your skin to make chemicals that themselves may be harmful.
I couldn’t tell. For some reason, the crew didn’t raise the lighting level in the cabin. They asked those of us nearby to turn on our reading lights and aim them toward the fallen and those helping them. They seemed pale, but that’s all I could tell.
We wondered if there was somehow less air being pumped thru the plane than should’ve been, and maybe it was affecting a few people. Not scientific, but my overhead air vent seemed to be flowing exactly like on every other flight I’ve made. The cabin crew also asked everyone in the vicinity to aim their air vents toward those in distress, and the vents seemed to be moving a lot of air.
We actually discussed the “mass hysteria” aspect of it amongst ourselves (later, away from the stricken passengers). But we came to no conclusions.
In a relatively evenly distributed male-female population if it’s mass hysteria the sufferers tend to be predominately female by a pretty significant margin. If the sufferers are equally male and female it’s unlikely to be classic mass hysteria.
I don’t have much to add. My first thought was some kind of food poisoning. The lack of a meal service may rule that out but perhaps all of the victims happened to eat at the same place recently, e.g an airport terminal restaurant or maybe a hotel restaurant.
A depressurization will drop the passenger masks automatically if the cabin altitude gets to about 14000 feet, however someone in bad health or who smokes is susceptible to hypoxia at a much lower cabin altitude than a healthy individual so they may be affected by a pressurization problem that doesn’t affect others and isn’t severe enough to cause the masks to drop. I don’t think that is likely though as the symptoms were fairly severe.
Was the cabin quite warm? Some people are far less tolerant of heat than others.
Oil (not fuel) fumes in the cabin is not unusual but there is a distinctive odor and again the passengers symptoms are a bit extreme.
Some other possibilities. They all had different issues that happened to present in a similar way and coincidentally at a similar time. They were part of a terrorist group creating a diversion so their colleagues could do something nasty but the colleagues chickened out ;).
On review I think food poisoning is most likely, despite the lack of a meal service.
I don’t know about the A319, but on our jet the passenger air vents aren’t part of the pressurization/air conditioning system. Their air supply comes from a cabin fan that simply circulates cabin air without recycling it through the air conditioning packs. This is different from the “recirc fan” that takes cabin air and mixes it with air from the engines before it is sent through the air con packs. The presence of air flow through the overhead vents does not mean the pressurization systems is working correctly. The pressurization air comes up/down through large side wall vents. Sometimes you might see mist coming from these side vents.
The cabin is normally set at a max altitude of 8000 feet and bells and whistles will normally happen in the flight-deck if the cabin alt gets above 10,000 feet (“cabin high altitude” warning lights at 9300 feet, passenger O2 masks drop at around 14,000 feet, pilots required to be on oxygen above 10,000 feet and passengers above 14,000.) That’s not a lot of room between everything being normal and the flight crew having to descend to keep the cabin altitude safe. It would be unlikely for a cabin alt of say 9300 feet to cause any additional problems in people than the normal cabin altitude would.
I wanted to point out ‘food poisoning’ can result from detergent being left on dishes, flatware, glasses; on ingestion it will cause vomiting, diarrhea and worse. Even if those stricken didn’t eat together they could have eaten from the same airport restaurant before their flight and gotten the same poor results. Good thing there were enough well people to help, that’s a scary situation.
A contaminant in the cabin pressurization system? Oil leak, deicing fluid, something else that would affect people with respiratory sensitivities first?
Well, oddly enough I have had the feel hot, get light headed and dizzy and just barely miss the passing out and vomiting part. I was gassed with hydrogen sulphide accidentally and very damned lucky it was just barely exposed as it can be fatal. Unless there was the holding tank leaking fumes into the cabin I doubt this was the cause as it really reeks at very low concentrations and pretty much everybody would have been affected.
Vomiting is frequently triggered by the sight, sound and smell of someone else vomiting, I suppose it could have been a survival tactic, Og over there ate something bad, better vomit just in case I just ate the same thing …
Even if there was no meal service on the flight, if there was a popular eatery next to the gate, it is not unlikely that a sizable number of passengers ate there. I base this on having eaten at the Five Guys burger joint next to my departure gate at Dulles. Probably at least 25% of the passengers and most of the grew were eating from there while waiting for the flight.
Now that airlines have cut back on meals, and the requirement to arrive early in case TSA is backed up, MANY more people are eating airport food now than in years past.