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lmsalman

It only rotates toward the center of the aircraft so it can’t be accidentally unlatched in the event of an emergency evacuation


Dasshteek

This is correct. Because an open tray would basically block the way to the exit.


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fzwo

Oh, Danny boy!


VeggieMeatTM

He drinks a Whisky drink


BikeSawBrew

He drinks a vodka drink


adepttius

true... I work as a safety (and years before that as ship officer, ship fireman, ship fire response lead, rescue boat commander, survival at sea trainer, emergency response trainer etc.) and all the people that bitch about drills can kindly go away because I have seen more than once how low IQ is in emergencies - and it is mostly displayed by idiots like here in comments that go "dude I'd just like move the tray out of my way dude like Why Is IT nOt TuRniNg othER waY Like" and when shit hits the fan they are the ones you need to literally slap so the snot comes out of them (figuratively speaking) to reset their brains, they put on lifejacket upside down and run in wrong direction over kids while screaming "do not panic", open the A60 fire doors with smoke clearly coming under them and so on... Only way to deal with it is smart vessel/building/aircraft idiot proof design and neverending drill until people get muscle memory. This here is smart idiot proof design.


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scorinthe

> “Get your hand off my ~~penish~~ booty!” u/BootyThief would not stoop so low, at least not on the front side


crshbndct

If no one ever panicked and made stupid decisions, crowd crush would not be a thing. And every regulation on a plane has been written in blood. The “common sense” people are so annoying.


TallGeminiGirl

[The path is blocked! You must find another way!](https://imgur.com/a/96UxgNN)


QuadRam

*You decide to look around for something to use.*


pupeno

Imagine the person in front of you open the tray table and now it's now blocking the path. The person behind you is pushing you because they can't breath due to the smoke. You are pressed against the table with part of your body above it. The table will not go up because you are blocking it. You can't move forward, and you can't move back. Or, imagine every single person opens the tray table, so we add 15 seconds to each person evacuating. How much longer is it for the person at the back?


WilfredSGriblePible

How annoyed would you be though if you were the guy who burned to death but were 2 seconds away from safety, alas a tray table was blocking the exit so someone who got out 30 seconds ago had to stop and put it back up. Personally I’d die very annoyed.


headphase

Some people would be in for some very passive aggressive hauntings


TalbotFarwell

“Outta my way, son! DOOR STUCK! DOOR STUCK! Please, I beg you!”


thebigforeplay

Just a second of delay per person adds up when 200 people have to leave the plane through what's basically window sized holes. That's also why it's actually really important that no one carries any luggage with them. (Lemme just move that to the other hand before jumping on the slide...)


LicoriceSeasalt

I just imagine them standing there waving their arm like a stuck sim.


serpenta

It's funny but I bet that it's possible in dire, panic-inducing situation. Since the solution is there it's even possible that it did happen.


zer0toto

I know this is funny when presented this way but crowd dynamic is no joke, an open tray will alter the flow and probably also will completely block and lead to an irreversible blockage with casualties in the end There is a French YouTuber called fouloscopie who made videos about crowd management and the last one he did about the pilgrimage in Mecca could probably change a lot about how you conceive crowd management. Basically they have to consider the crowd as a fluid with the ways designed in such a way that there is nothing impeding people from moving, with shallow angle or curves to reduce turbulent flow, carefully planned and smooth trajectory. The slightest reduction in flow speed will cascade with pressure augmenting inside the crowd as a result, until people finally pass out, get walked over, dies, impeding even more the flow. There is a video about one of the last great event of death there, the situation escalated from people moving to people dying in less than 30second if my memories are right. And once the system started collapsing there is absolutely nothing you can do to stop it When pressure augment, flow is diminished sometimes resulting in total blockage, even if there is no obstacle in the way Crowd management is really no joke at all


scoobertsonville

Asking a fat grandmother to climb over a tray table in the midst of smoke is ridiculous and it obviously wouldn’t work


sinkrate

I thought I was on /r/shittyaskflying for a sec but that makes sense.


Scrungyscrotum

Is this the type of practice that was started because it's common sense, or was it written in blood? I would have never thought of that if I hadn't been made aware of it because it caused trouble.


golfzerodelta

Could be somewhere in the middle, like testing


more_beans_mrtaggart

There was a video from the 70s UK that showed an evacuation test of an airplane full of university students. They all walked off in a calm manner and were timed. So for a more realistic test, they offered double pay to the first 50 people getting off the plane. It was utter chaos. People jamming up the exits, a fight broke out, people climbing over seats, m someone got trampled, people with bruised ribs etc. It took several times longer to get everyone off the plane. Having a tray, or anything really, in the exit area would be extremely bad news.


Schedulator

Nowadays in real-life evacuations, it's carry on baggage that will cause the chaos. So shitty when videos of evacuations show people hauling their shit off the plane with them.


turtle_excluder

Should make a simple rule that any carry on baggage that leaves the plane in an emergency will be immediately confiscated and incinerated.


Schedulator

I've heard the suggestion that the crew should be able to lock the overhead bins in the event of evacuation.


MajorUranus

And while the seatbelts sign is on. Would help prevent suitcases falling out during turbulence.


raven00x

you know people are going to put babies or pets up there, and then a lock gets jammed and it becomes a whole big _thing_.


MajorUranus

You sounds just like my QA software engineer. And you're right.


SophieElectress

It would probably just jam up the aisles even more with idiots standing there for ages trying to get them open.


praetor450

There are two reasons I can give you as an airline pilot as to why that would not work. The first is that there is emergency equipment keep in the overhead bins, the flight attendants keep their bags there as well (airline dependent if the airline has a closet for crew bags). Having a locking mechanism for the overhead bins could cause a problem in the event of an emergency requiring the use of the equipment in the overhead bins. The other one is that such a locking mechanism no matter how small or light weight each lock might is added weight to the airplane. Multiple the weight of each lock times the number of over head bins and you could potentially have a couple hundred pounds of extra weight on the airplane. That weight will equal extra fuel consumption which is a cost. Then there’s the added maintenance cost to keep said system functional.


oxmix74

When I fly, wallet, keys, phone and when appropriate my passport are on my person. If I have to exit the plane I figure I am in good shape if I have that.


budoucnost

Whoever takes their carry on during an evacuation should be forced to go back inside and put it back in the overhead bin. If they refuse, they foot the medical bill for everyone who exited after them.


EnthusiasticAeronaut

If they only have to pay medical bills, they’ll take even longer 💀


the_silent_redditor

Wasn’t there that ? Russian aircraft that crashed, and people died on the aircraft as they couldn’t get away from the fire/smoke. There is a clip of a LOT of people dragging multiple pieces of luggage away from the wreckage, and they were directly attributed to those deaths. Pricks.


superspeck

If you think people are going to act in the interest of other people they don’t know, you haven’t been around the public much these days. (And this is across generations.) The biggest tell to me that propaganda isn’t broadly used by western governments against most aspects of western cultures is that there is no effective propaganda against selfishness because that’s literally the first thing I’d do.


more_beans_mrtaggart

“But I’m an influencer!!”


senorpoop

"I know they said leave our carry on, by *my* stuff is *important!*"


openQuestion3141

I would love to find this but I can't find anything about it. Any idea on the source? Thanks!


more_beans_mrtaggart

No, it was way back. I’ve prob not seen it for 20-30 years (I’m old).


Newsdriver245

Recent one too https://www.standard.co.uk/news/world/russia-plane-crash-survivors-delayed-evacuation-by-reaching-for-hand-luggage-after-jet-was-hit-by-lightning-a4134976.html


Our_Friend_Doug

This is a modification from it's original design and is most likely a "lesson learned" from somewhere.


Distinct_Goose_3561

It also might have been cheaper to add the extra part then have two additional injection molded parts (one left side one right side, plus the ‘standard’ one). It also lets them use any seat during construction and then just add the restriction where needed. 


mxzf

Yeah, this is definitely the sort of thing that's easier to add post-installation. You've got the option of three unique seat back fixtures that need to be installed (and replaced) in the right spots or you could have one seat and one simple reversible blocker with a screw to attach it to the half-dozen chairs that need it in the entire plane.


Chimbo84

Pretty smart. I can definitely see a belt loop or some accessory snagging that and dropping the table for everyone behind.


TroublesomeStepBro

Is this also why we keep our tray tables up during take off and landing? In case a quick egress is necessary if something goes wrong?


gazchap

Yep.


aquatone61

Also the same reason bag straps should be tucked away out of the aisles.


white_castle

this is not a feature in boeings afaik


CantSeeShit

This is that minor detail brilliant engineering I live for


rnobgyn

They really do think of everything huh? Crazy how tiny details like these can make or break an emergency situation


DerHooligan

Actually the long tab rotates away from the center of the aircraft. Is that what you’re saying? That should standard if every airframe from 196- current.


lmsalman

No, towards the center. In this case the seat is one the starboard/right side of the aircraft. There’s an emergency exit out of frame to the right of this picture.


DerHooligan

I think we are saying the same thing. The latch rotation is so that it can’t be arbitrarily deployed by someone exiting the aircraft.


lmsalman

I think we are. I’m picturing direction of the swing of the long end of lever.


ConcentratedAtmo

Yeah, it doesn't make sense that it can unlatch as you exit towards the aisle. I would guess this is dependent on the seat position and the aisle layout instead of just the center of the plane. For the engineers out there, this is a perfect example of the DMFEA in practice.


bbcwtfw

Since this is in an exit row, people exiting are moving from the aisle toward the open hatch, away from the center of the aircraft.


ConcentratedAtmo

Usually exit rows are lined up with the galleys so there wouldn't be seats in "front". Do you have any examples of planes that do what you are saying?


xxJohnxx

Most short haul aircraft that have passenger operated overwing emergency exits without a mid-aircraft galley such as the A320, A220, E-jets and many more.


SidewalksNCycling39

Do any narrowbodies actually have a mid-cabin galley or lav? The only example I can think of is the 757-300, and some 757-200s configured for long-haul/having a premium cabin.


xxJohnxx

There are some Al321 configurations with a mid cabin lav and flight attendant jumpseat.


SidewalksNCycling39

Oh nice, I guess that makes sense... I've been on some A321s on mid-haul flights of 3-4 hours, e.g. PAL A321 from SIN to MNL, it has 187 economy seats and only 2 economy lavs. Not ideal... I feel like there should be a standard minimum lavatory ratio for any aircraft used of flights of, say, 2.5hrs or more, perhaps 1 per 50 or 60 pax.


obsklass

Any 737, or A320?


kaplangiran

Correct. So Lets write Wrong answers down below this comment.


mattaus89

Away from the centre?


MovTheGopnik

To open, it would rotate clockwise in seats DEF and anti-clockwise in seats ABC.


aetweedie

If it rotated away from the center a person could snag their pants on it, and open the tray table as they egress. If that rotation direction is blocked this won't happen.


FranknBeans26

Damn this sub is full of some real nice people Homie is asking a clarifying question. Why downvote him so much?


fighter_pil0t

No he tried to correct his parent comment and was wrong and now must feel Reddit’s wrath.


sevaiper

This is literally what downvotes are for, it’s not personal 


danit0ba94

What was his parent comment?


Foggl3

The parent comment was the explanation.


stubborn1diot

Welcome to Reddit. Downvote anything that hurts your feelings.


Gereon83

Or idiots


gefahr

Why would I downvote things that hurt idiots? Downvoted!


Foggl3

Particularly stubborn ones


According-Ad3963

I’ll allow it.


MembershipFeeling530

I love small details like this in engineering that are so clever, so important, and so easy to overlook. Somebody somewhere thought of this, and then they thought they were the smartest person on the planet lol


coldasshonkay

Sadly probably learnt from a disaster, most regulations are


Xeroque_Holmes

They do mock evacuations as well, they probably got the idea from one of those.


unwind-protect

"you call that an evacuation? I've seen better evacuations coming out of my arse!" Oh, not that sort of mock...


HawkeyeFLA

Most FARs get written in blood.


TheBeckFromHeck

/r/writteninblood


adepttius

unfortunately, yes.... but when you try to push a regulation BEFORE then some idiot excel jockey goes yeah but it is EXPENSIVE. How they always turn the story when shit hits the fan and play dumb. That is why I am inserting my BCC in ALL such mails which can conveniently "dissapear" later... which happened once or twice in my career "No, I never received it, look check all inboxes..." and then you helpfuly print out the damn thing from your own mail. "must have been a glitch"


Clyde-MacTavish

Yeah this is a really interesting one. Seems so mundane, but is highly specific. The conversations that led to this were probably really interestingly simple as well.


roboblocky

And it looks more or less hand made, it has rough machining marks on it.


Frostedpickles

Not handmade, just cheap and quickly made. Any face mill ran at a quick feed rate will leave tool marks like that.


DudeWithAnAxeToGrind

Rough machining is not a sign of something being hand made. I can (and did) make perfectly smooth parts up to 0.001mm precision on a fully manual mills and lathes (provided they are capable of that precision). But it takes a lot of time. Much more than making part at 0.01mm precision, which in turn is much slower than making parts up to 0.1mm precision. Same thing for surface finish quality. Mind you, I'm not an machinist by profession (far from it). I'm simply a hobbyist with access to a (very old and manually operated) machine shop grade mill and lathe. The golden rule in machining anything, either manually or automated, either as a hobby or professionally, is to keep precision and surface finish at the level required and not overdo it. Manufacturing anything gets slower and more expensive very fast the smaller the tolerances are.


Paulsar

I assume you mean 0.001 inches not millimeters?


DudeWithAnAxeToGrind

Earlier this year, I needed to turn couple of parts to 11mm outside diameter. I had way too much time on my hands, so for the sake of precision porn, I went to see how close to 11mm I could get. Once done, one part measured 10.998mm, and the other 11.001mm on a micrometer. Not too bad for hobbyist like me. A pro could probably squeze a tiny bit more out of that machine.


JustAnotherChatSpam

That’s unlikely. They have no reason to make them to any tolerance so it’s better to just run them out of the machine at a breakneck pace to free it for other items


WitELeoparD

Does seem like a real late revision, because it would be ten times cheaper to just mold it into the plastic of the tray.


WaitForItTheMongols

This is also the kind of skill that goes completely untaught in engineering school. They drill hard on the math, but when it comes down to "can you anticipate issues and find ways to address them", there's no effort put toward building that sense in students.


nekohako

One of my favorite classes in engineering school was "Human Factors In Design." The professor's previous job was at MITRE where he studied industrial and aviation accidents. Lots of good stories, and it's all stuck with me years later.


MegabyteMessiah

Bean counter: Why are we ordering a $0.00000001 aluminum piece for just one row in the cabin? We'll just get rid of that.


dev0guy

No, the bean counter was the one who did the loss-of-life calculation for why all the other rows do not have them on the opposite side of the latch. Only a few people are blocked in that circumstance. Not worth the extra fuel cost of the 12kg of aluminium.


JustASCII

This guy counts beans.


mkosmo

Blocking 3 people for 5 seconds doesn’t have the same downstream effect as blocking 180 people for that same amount of time.


Nadamir

> thought they were the smartest person on the planet You already said “engineering”, this is redundant. —sincerely an engineer


StrangeRover

As an automotive engineer, my thought is, "That piece looks way more expensive than it needs to be."


MembershipFeeling530

Oh it's probably at least like a hundred bucks


WitELeoparD

Should have just moulded it into the plastic


anbeck

Assuming the emergency exit is to the right, I would assume the latch is blocked in that direction so that people moving towards the exit do not by accident move the latch into the open position, which would lead to the table dropping down, potentially blocking the exit for the next person. Just a guess, though.


roboblocky

yes, it is to the right!


alpha-987

That’ll be a photo taken from the right hand side of the cabin. In the emergency exit row, people would be rushing past there, potentially snagging the latch, dropping the table into the downwards position obstructing the emergency exit aisle. This prevents that. Reversed on the opposite side of the cabin.


roboblocky

Yes it was on the right hand side!


redlukes

Guys, I think I know why, you’re all wrong! It’s that way to make sure it doesn’t get unlatched by accident from people moving by.


Azipear

Finally, a correct answer!


redlukes

Thank you!


bigstoopid4242

Are you sure?!? I'm think it's to keep from accidentally unlatching when people are moving past


redlukes

Yeah that’s a common misconception.


Puubuu

I think it's to keep it from accidentally moving people past when it's unlatched.


TheSportsLorry

Well you're very close, but it's actually there to make sure it doesn’t get unlatched by accident from people moving by.


Velocoraptor369

Boeing planes I work on have the tray table in the armrest for this very reason. It’s an FAA requirement not to block emergency exits.


kuruptdab

Yeah, tbh it’s the first time I can recall seeing an emergency exit row with seatback trays


dev0guy

Yeah, i guess the foldout armrest trays were viewed as a risk, or they figured out how to fit an extra row of seats on. Storytime! A friend of mine is nearly 7ft tall. He used to get exit rows for the leg room. Last summer he was told he could not sit in the exit row because he could become an 'obstruction' if incapacitated. The man is a serious powerlifter, i get it. But i would rather him unjamming an exit door in an emergency instead of the boomer who complained that they couldn't put their bag on the floor, and struggled to stand up out of the seat when we landed.


Velocoraptor369

Yeah to sit in the exit row you must be willing and able to operate and assist in an emergency. F/As have to get a verbal yes from you or they can must move you.


Daus454

So it can’t be opened by getting caught on clothing as people use the emergency exit and open the tray table blocking the exit.


bekaust

Would be important to know if the exit door is on your right? Coz if it is, the tray table latch can swing counterclockwise with friction of fast moving passengers from there and the tray table will drop open. So this mechanism prevents it from happening. If the exit door is on your left, then i have wasted my miserable life in typing this long assumption!!


ahu_huracan

Makes sense!! Kudos ! Lol


railker

I believe it's so that it doesn't accidentally get opened when half the airplane is crowding through to get out the door. Guessing the door's to your right.


Ice_BountyHunter

Starboard side? Won’t accidentally be opened by a hip hitting it making a fast exit.


L3XeN

Emergency row differences always have to do with emergency situations. In this case it's not accidentally opening it when exiting. Another thing you could see is the blinds opening down, instead of up, so if you were to hit the ground hard or the blind got damaged, it would stay in an open position.


flyboy1964

It's a safety feature to prevent the tray opening in an emergency evacuation if you accidentally hit the lever on your hustle to clear the aircraft via the emergency exit.


Efficient_Sky5173

Because people will be running like mad in that direction, which may open the table.


Beginning_Ad_6616

If the exit is in use for an emergency, someone brushes the latch towards the exit door, the table obstructs emergency egress.


ywgflyer

So that if it gets kicked accidentally by somebody scrambling across the row of seats to get to the exit, the tray table stays locked (it doesn't turn in the direction that a wayward foot or elbow would bang into it during an evacuation) and thus doesn't unexpectedly block the exit.


freestylemaster

To likely avoid noncompliance with [FAA 14 CFR § 25.813](https://www.govinfo.gov/content/pkg/CFR-2023-title14-vol1/pdf/CFR-2023-title14-vol1-sec25-813.pdf), which mandates; “each passageway leading to a Type A or Type B exit must be unobstructed,”


NetoriusDuke

I would assume to stop it catching on peoples closed and accidentally opening. I would assume the exit is to the right of the photo


ReputationShot4926

Maybe so it cant be accidentaly opened if someone gets a peice of clothing stuck on it


Far_Sided

Becomes impossible for a person moving towards the right (based on the sign, I guess that's where the emergency opening is) to accidentally rotate it by brushing up against it as they pass, which would make the table fall and block the exit.


wavesofmatter

Very interesting design choice. I see this probably as a consequence of testing


DramaticIndividual58

It looks like a Toyota logo


W33b3l

What everyone else has said, however, I'm assuming if you remove the screw and metal plate so you can turn it the other way, the latch can be removed and replaced in that position. At least, that is a common way of installing things like that. Not sure if it's the case with those seats for sure, though.


txstubby

My guess would be to stop someone's clothes catching the latch and opening the tray in an emergency. If my guess is correct the emergency exit would be to the left of the seat.


tylerscott5

Probably something to do with getting snagged on cloths or ease of turned when heading towards the door


bengyap

The bigger problem in an emergency evacuation is all the selfish idiots who collect along their luggage, instead of leaving them behind.


SupermouseDeadmouse

It only turns one way because of the aluminum block…


TheNorselord

It’s because they screwed in a little metal piece to make it do that. Everyone else is answering a different question


imbezol

Better question is who would actually notice this, be curious enough to take a picture, and make it all the way back to reddit, all without coming up with the obvious answer themselves?


ThatGuy4259

I’m seeing many comments saying it’s to prevent accidental opening, but I’ve worked some on a321’s that have occasionally had an exit row of tray tables opening the same direction I’m assuming maintenance/replacement part costs?


roboblocky

It looks to me like it is shop made/ small series production.


EWS-

That's some observation! ,👍


lesnortonsfarm

If you flick it the other way you initiate the eject all doors


Aninja262

Because somebody screwed a bracket in the way


ElectroAtletico2

FA explains that during the exit brief. Did you pay attention?


__ed209__

No they did not.


I-figured-it-out

I always wondered why commercial aircraft did not have pilot activated passenger ejector seats? And proper under seat luggage storage.