This.
I hate to fly because I am prone to motion sickness. This helps reduce the changes of my field-testing a barf bag.
Does this happen on commercial flights? I’ve never been weighed when I check-in or board, so how could this statement be true?
Standard weights are used. They may only use standard weights if the passengers are average. If you’re carrying a plane load of rugby players you are supposed to get actual weights. I’ve never seen that happen but I’ve also never been on a plane with an unusual load. The larger the number of passengers carried, the closer they will be to the average. That’s partly why small aircraft aren’t permitted to do this. Not only does a small aeroplane not carry enough people for them to approach an average total weight, but it also takes a much smaller weight increase to put one over weight or out of trim. Every now and then the aviation authority revises what standard weights should be. Not surprisingly the standard weights have been increased in recent years.
I sometimes see incident reports in our company filed by flight crews who discover that there are more children on the aircraft than notified in the load sheet. Their concern is that if these errors aren’t caught, the aircraft could be out of trim. This is on BAE146 and B717 aircraft.
Although it was on a small Beechcraft 1900 (19 passengers, 2 crew), one of the contributing factors to this crash was an overweight plane with a centre of gravity about 5% aft of allowable.
This crash of a Challenger 600 business jet had a similar cause; the centre of gravity was too far forward and the airplane was unable to rotate on take off.
I can’t think of any accidents or incidents involving larger aircraft in which passenger placement contributed to cause, but weight and balance is certainly calculated for them as well. When loading the plane with passengers and cargo, of course, one does want to avoid thissituation.
Seconding this. I also want to point out that even among their teensey sample size, there is no crash template. Airline disasters tend to be caused by a variable complex combination of individually unlikely occurrences.
In the Sioux City crash, for instance, the plane landed as it landed (breaking into three sections) because they didn’t hit a wind gust right before they touched down. (The pilots were manually reacting to air currents while attempting a landing because they had no horizontal stabilizer.)
Whereas for the Tenerife airport disaster, survival depended entirely on the point of strike, which depended on how sharply the KLM plane banked upward after the pilot saw the Pan Am, and where the Pan Am was positioned relative to the strike as it was beginning to taxi.
Sure, if you could guarantee that the next crash would be identical to Sioux City, identical air currents and all, you’d know not to sit in first class. The next crash is going to be completely different, and caused by a completely different unlikely set of factors.
Ejector seat.
Earlier this month I was on a Southwest Airlines flight. About 130 seats on the plane, and only 40 passengers i.e. nowhere near full. As you may or may not know, Southwest Airlines does not assign seats when you check in. Seat selection is on a first-come, first-serve basis. You line up at the gate in the order that you checked in (smart people check in online 23 hrs 59 mins before departure), get on board, and pick whichever seat you want. The crew counted up the number of passengers once everyone is on board, but I don’t believe they made any kind of record about where passengers were sitting, and they didn’t ask anyone to relocate for any reason.
Yeah I’m aware that some airlines have free seating. I don’t know what system they use but they would certainly have one. Their existance doesn’t invalidate what I’m saying. If you are flying Southwest by all means sit where you like, though you may find that if everyone decided to sit in the back some may be asked to move. It’s likely the trim may be done for a range of possible seating positions. As an example of this, my company doesn’t normally carry passengers. On the rare occasion that we do have one I’d do a trim sheet for the passenger sitting down the back and one for them sitting up the front in the cockpit jumpseat. That way they are free to sit where they like, but ONLY because I have covered all of the options.
Speculating only, but I’d expect free seating companies aren’t able to work to the limits of trim the way airlines with allocated seating can.
It’s possible that so few passengers, likely more-or-less scattered around a 737 did not risk taking the plane out of it’s CG range, but it’s also very, very probable that the amount of cargo - and it’s loading/location - onboard the aircraft was changed in order to ensure that the plane remained within its allowable limits. The amount of fuel on board, and its location, was also likely adapted for the small passenger load.
I think it is much easier to put a small plane - like a regional jet - out of CG than it is a big one, simply due to the relative magnitudes of the passengers to the plane. It is a serious concern for smaller planes.
[musing]I don’t think Southwest has ever had a large fatal accident where many/most on board died and where there may have been a post-impact fire. Although DNA is used nowadays to confirm the identities of victims/body parts, I would think that in a free-seating plane where 150 passengers could sit anywhere they wanted, that job would become much more difficult since it wouldn’t be possible to narrow down a likely victim to a handful of remains in a certain area of the aircraft. It would certainly make the cost of an investigation somewhat greater! [/musing]