One thing we can all probably agree on is that flight attendants have seen it all.

As you might expect, some of what they’ve seen as they’ve walked those narrow aisles isn’t pretty: passengers clipping their fingernails, or applying nail polish or perfume, or using battery-operated shavers.

If in-cabin personal grooming seems more like an urban myth than something you’d ever do, you’re well on your way to being voted Passenger of the Year. But before you write your acceptance speech, make sure you’re not doing some less obvious things that could be irritating or dangerous in flight.

Put your bag where it belongs. Most of us are unaware of a basic rule that applies to every commercial flight: In the cockpit, the pilots are preparing for a routine flight; in the cabin, the flight attendants are preparing for an evacuation, explains longtime flight attendant Toni Vitanza. And the biggest safety hazard, she says, is improperly stowed luggage that could potentially obstruct passengers trying to evacuate. Further, “the FAA can fine me and the airline $1,100 per bag for every bag they find that is not all the way under a single seat,” Vitanza says. “You can’t put your bag in your lap or behind your legs or your head. It’s not legal.”

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Vitanza has heard tell of the FAA enforcing that fine and has confiscated bags from passengers who refuse to understand the problem. “The stupidest thing I see people do on a plane,” Vitanza adds, “and it’s almost always women, is putting their bag under the seat in front of them and wrapping the strap around their leg because they don’t want to forget it, lose it, or have it stolen. I also see them thread seatbelts through the straps of their handbag. During an evacuation [it would] hamper you, and if I see you do it I’ll make you undo it.” Adds former flight attendant Jennifer Worrell, “if you're in a bulkhead seat, place your bag in the overhead bin. Just do it. Don't throw it under your feet or in the corner and cover it up with a blanket.”

Listen to the safety rules. Some airlines prohibit electronics usage shortly after the cabin door closes, while others wait until the plane taxis. Whatever the policy, it’s likely that many of us are tuning out the in-flight safety instructions, whether they’re being delivered by a live flight attendant or a video monitor. “If you’re talking on your cell or watching a DVD you’re not listening to my instructions,” Vitanza says. Passengers who “completely ignore the ‘routine’ safety demos” also trouble longtime flight attendant Danny Jacques. “All airplanes are not alike,” he says. “Exits are located in different locations and operate differently [depending on the manufacturers or models] or types of aircraft. What was routine about landing in the Hudson?”

Mind your health. “I had a male passenger pass out ‘on’ me in a lavatory. I opened the door to step out and he landed in my arms, pinning me against the wall. The reason was he was dehydrated from food poisoning,” recounts former flight attendant Beth Blair. And while passengers may not necessarily know they’re ill before they board, it’s never a good bet to push through if you think you are.

Further, Blair contends that many in-flight medical emergencies are avoidable. “Another common situation is when diabetic passengers have seizures or pass out in flight — or come close — because they didn't eat before boarding,” Blair says, adding that on one flight “I had parents bring their severely peanut-allergic child onboard ‘hoping’ the child didn't have a reaction while in flight. The child did have a reaction and had to be rushed to the ER upon landing.” She says families can research if an airline serves peanuts regularly and that upon request some airlines will offer peanut-free flights. Melissa Stoller, a frequent flier and mother of three, says she’s found flight attendants to be accommodating when she explains that one of her children has food allergies. “Although I always try to pre-order special meals for her, the meals sometimes don't arrive as we expect. The flight attendants are always very kind and do their best after I explain exactly what my daughter can and cannot eat.”

Accept that not everyone loves your dog. If you carry a pet on board, it belongs in its carrier, which must be stowed in the seat in front of you during take-off and landing, Vitanza says. Even for those owners who obey the rules, the issue might come later. “Let’s say your seatmate is allergic, or doesn’t like dogs, or is eating. You bend over, pull the carrier out, and put it in your lap. You’re allowed to do that. But should you?” Worrell adds that you’ll also want to resist removing your pet from its carrier in flight. “The last thing you want is for little Fifi to disappear. There are lots of crevices and hiding places on a plane, not to mention the tangle of legs and feet in the cabin.”

Be kind. By far, passenger rudeness toward flight attendants and fellow passengers was the prevailing pet peeve of the flight attendants interviewed for this article. And while overt special treatment attracts too much attention from supervisors and other passengers, flight attendants will try to find a way to repay your kindness. “Passenger freebies such as liquor and extra meals are certainly a thing of the past,” says Blair, “but being kind and respectful can land a ‘middle seater’ in a vacant aisle or window seat [or help] a passenger escape a seat near a lavatory.” Adds Vitanza, “if a passenger agrees to switch seats with you, your offer to buy that person earphones or a drink “is going to make you look real nice to a flight attendant if you put that request through her. When I see a passenger being nice to another passenger, I want to be nice to that nice passenger.”

If one of her children needs something during a flight, Stoller says it sometimes pays off if she has one of her kids ask the flight attendant. “Recently, on a flight where passengers had to pay for snacks, my daughter was rewarded with several complimentary snacks after she smiled and asked politely and sweetly for the snacks herself.”

The bottom line, Blair says, “is that passengers can ‘get in good’ with their flight attendants by simply acknowledging the fact that their attendants may have been on the plane since 4 a.m. A simple, ‘Have you had a long day?’ with a hint of compassion can go a long way.”

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