kale73

Q. Did you press the call button and ask the FA who responded to bring you an empty water bottle for use as a urinal at your seat?
A.

milepig

This is all very interesting, but you won't get very far with your thesis adviser without evidence of a literature search.

hobo13

Kind of like the yellow speed limit sign advising you to go 45 MPH around the curve......

the fasten seat belt sign is merely a suggestion.

Jackstay

I imagine that has a lot to do with it. I'm thinking that from a conservative safety point of view and to the legal department in particular, it looks a lot like Pascal's Wager:

Seat belt sign on, turbulence encountered, nobody hurt = good
(Seat belt sign on, passenger hurt in turbulence = defensible)

Seat belt sign on, no turbulence encountered, passengers inconvenienced = OK

Seat belt sign off, no turbulence encountered, passengers FTMATC = OK

Seat belt sign off, turbulence encountered, somebody hurt = BAD

That being said, as a retired transoceanic pilot I know that even with modern weather radar it is impossible to pick a way through the skies without encountering turbulence, that often the best indication in clear air of smoothness ahead on the flight path is a report from other pilots just ahead of you (if you listen on Channel 9 you'll hear a lot of notes being traded concerning "the ride"), and that weather briefings are properly conservative and often mention the possibility of turbulence. In that last case, if there is no other aircraft out there to make a report as to conditions ahead then the seat belt sign will stay on for as long as it takes to cross the forecast area of possible turbulence. This includes climbs and descents where a layer of turbulence may be encountered. For a transoceanic flight, that can be a long time because weather stations and other aircraft can be few and far between. Bottom line is it is the known unknown about turbulence, especially clear air turbulence, that can lead the seat belt sign to stay on for long periods even in clear air. Although it is also true that sometimes pilot do forget to turn it off, especially if it has been on a long time in smooth air.

I think UA does a much better job than most in trying to keep the seat belt sign meaningful by turning it on and off throughout a long flight. Maybe my butt has been calibrated by so many years on airplanes, but I often can predict when the seat belt will come on a few minutes in advance by the motion of the airframe. This leads me to think that the turning on of the sign is the result of attention by the flight deck crew, not a random event. Furthermore, I know that they have a lot more information, both in general and moment to moment, than we in the back so I take the sign seriously.

Lastly, I have often thought that the US aviation industry/regulators should try and devise a safe harbor policy for seat belt sign usage that would explicitly limit legal liability as long as best practices are followed.

eng3

Although it is much less prevalent now, I usually listen to Ch9 when available. I'll hear the Pilot ask about the ride in their sector. If they say it is clear, I will see the seat-belt sign go out. If I hear a report of chop for the whole ride through the area, I'll see the seat-belt sign stay on. I think the pilot is limited to what he can see on his radar and the reports that he gets. Sometimes if it is a grey area, I figure he will play it safe and leave the seat belt sign on for extended periods of times.

As for passengers getting up, I think most will not risk their safety (or getting scolded by the FA) unless it was a bathroom emergency. Although I've seen FA's tell passengers to sit down, I've never seen one actually stop someone from using the restroom when they really needed to.

austin_res

I was on a Singapore flight and the seatbelt sign was on for a long time even though there was no obvious turbulence. When passengers tried to use the restroom the FA's ordered them back to their seats and made several announcements "no one is allowed to use restrooms".

RedHeadFlyer

This is one thing I really miss about the channel 9, now that it's disappearing. I could manage turbulence and bathroom breaks much better. Turbulence 80 miles ahead? Hit the bathroom right away, light is coming on soon. It's forecast to be light to moderate turbulence versus occasional light chop? Tighten the seat belt and finish the drinks. Ride reports are fine, been totally calm, and the light's been on for 30 minutes? Ask the FA if the pilot forgot about the light (many times the light went out right after asking).

I totally noticed an UA vs. CO difference in usage even prior the merger. UA was pretty good about turning it off, but when it was on, the FAs were serious about telling people to get back in their seats when the got up. CO left it on more, but the FAs usually wouldn't bother people unless it seemed serious. Like on UA it was a warning, but on CO it was an advisory. The difference doesn't seem as stark now.

LordHamster

Internationally, I fly CO routes exclusively. I avoid former UA routes like the plague... that said, CO pilots have the annoying habit of NEVER turning off the sign.

EWR-FRA, EWR-HKG, EWR-PEK - all routes I've flown without the seatbelt sign ever once coming off. I'm starting to wonder if CO ordered their 777s and 767s without the seatbelt light (on/off) toggle option.

Emma1420

I think this is less of a PMUA vs. PMCO thing and more of US pilots versus everyone else thing.

Based on my very limited experience the seatbelt sign is left illuminated far longer on the US carriers. I've been on domestic flights where its never turned off and international flights where it's illuminated for about 50% of the flight. And, on some flights it's clearly been turned on simply so the FA's can serve a meal without dealing with passengers. This is direct contrast to non-US airlines that turn off the seatbelt sign immediately upon reaching cruising altitude and keep it turn off for all but significant tuberlance.

luckypierre

That's been my experience.

sfo

I have noticed that when the seat belt sign is illuminated for a long time, some passengers in economy will start to use the lav's and an announcement is made that they are to return to their seats and fasten their seat belts. Many times I have been in the first class cabin and some first class passengers are up using the lav's or looking for something in the overhead, nary a word is said by FA's to first class pax.

Also I think that when the fasten seat belt is illuminated for a long time and there is no turbulence, some think that it may be the "sky is falling" syndrome, which never happens.

Mats

This comes from FAA Air Carrier Operations Bulletin (ACOB) 1-94-27. The crew are required to periodically remind passengers that the seatbelt sign is illuminated.

Kacee

Actually, many non-US carriers turn it off before the aircraft has reached cruising altitude. I've been on flights in Asia where they turned it off around 10,000 feet - when you still practically need ropes and crampons to climb your way up the aisle

goodeats21

^ I have experienced the same...and I like it much better that way.

smxflyer

DEL-EWR earlier this week. Seat belt sign was on for a continuous 6 hours with intermittent mild turbulence. At a certain point, a good amount of people just began getting up and using the restroom. FAs did not seem to mind.