
Airplane boarding simulations - ColinWright
http://menkes76.com/projects/boarding/boarding.htm
======
mcargian
None of these simulations seem to take into account the usual activities that
delay boarding:

* Not all of first class boards early, many flyers stay in the lounge till later and then hold up the aisle getting their bag into the overhead

* Passengers board together regardless of boarding order. Friends flying with an elite member can board early and not with their group.

* When the overhead is full passengers must swim upstream to bring their bag to be checked.

* Although there are plenty of bathrooms near the gate, many passengers insist on using the lav the minute they board. They again end up swimming upstream holding up the queue

* Seat stealing - whether intentional or not, some passengers help themselves to a roomier exit row seat (or on one occasion I've seen them in first class) hoping no one shows up to take that seat. Once the passenger with that seat arrives, the original passenger has to get their belongings, perhaps clear the overhead and again possibly fight their way against people boarding.

Southwest's self serve seating helps in some regards, but this style of
boarding will never be used my the major carriers - at least in the U.S.

edit: typos

~~~
personlurking
I prefer Southwest's self serve style because it rewards those who check in
earliest. Well, that is, if you consider it rewarding to be the first on and
first off (as I do when I get to sit in row 1).

On a recent flight using Azul (Brazil's "Jet Blue", same owner), people were
boarded via the front and back at the same time. First time I had seen that,
though not sure if it was any quicker. Perceptions of quickness are often
dependent on where you are sitting.

~~~
pbreit
Southwest's procedure used to be better when you had to get to the gate to get
your number. That really encouraged people to get to the gate early. Now that
you can checkin at home you can waltz to the gate.

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TheFuture
Maybe this is completely dumb and impractical, but could there be a way to
remove the seats from the plane, individually or in groups, maybe on a track
(overhead?) like a roller coaster, so that there could be a large boarding
area with plenty of room for people to get situated. Then once everyone is in
their seat, the seats would roll and lock into position.

This would also allow you to quickly deplane, but have the next group of
passengers already seated, ready to slide into the plane.

The boarding problem is human, and also spacial. And you can't really get rid
of the humans, but you could change the space.

Freight transport has been containerized, how can we do it to passenger
transport?

~~~
ColinWright
I discussed this some years ago with an airline engineer. There are many, many
practical problems. A pressurized fuselage with a separable section big enough
to load passengers on and off is one of the simpler problems. I was left with
the impression that it will never[#] happen.

[#] "Never" is a long time. Certainly "not soon"

~~~
TheFuture
I was thinking weight would be the biggest problem. Maybe with new materials
its not a problem.

We have these automated warehouses and factory floors with robotic carts that
can precisely navigate, pickup and deliver loads without a lot of
infrastructure needed, that's kinda where I'm coming from.

I'm thinking the solution would have to work with the existing sized doorways
for it to be adopted.

~~~
ColinWright
The real alternative is to have a mock seating area with ov erhead bins.
Everyone gets settled, the the bins are loaded and locked into place, and the
passengers walk on without hand luggage. They then know where to sit, and
don't spend time futzing with the bags and bins.

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tocomment
Here's a clever idea I just thought of. The airline could keep the overhead
bins locked while everyone boards. So everyone just comes in and sits down,
keeping their belongings on their lap. (It seems like that would be a lot
faster)

Then once the plane starts taxi-ing the overhead bins unlock and people can
put away their belongings (since you have to wait at least ten+ minutes to
taxi and take-off it seems like this wouldn't cause a slowdown.) Plus you'd
get an extra efficiency because the person in the aisle can load the bags for
everyone in his row.

Should I patent this ... :-/

~~~
larrydag
I agree that the single biggest improvement in airline boarding should be with
the airplane and airport design. The fact that there is only one entrance/exit
makes for an automatic bottleneck and limits options. Most planes are equipped
with a rear door or on larger planes a mid-door. They should allow those doors
to be used during boarding. Seems that this would be the most cost efficient
and reasonable gains should ensue.

~~~
adavies42
the really big international flights sometimes board 1st (and higher, if we're
talking about lines like singapore or virgin that have luxury classes) through
separate doors from us proles.

of course, that only helps _them_....

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chewxy
I was bored on one flight and so I actually wrote a quick and dirty simulation
while on the flight: [http://blog.chewxy.com/2012/04/04/a-better-passenger-
boardin...](http://blog.chewxy.com/2012/04/04/a-better-passenger-boarding-
system/) . My main complaint at the time had been the inefficiencies brought
about by loading luggage in the overhead compartment.

I was actually quite surprised by the simulation - that queueing people into
odd-even queues make for faster boarding.

Caveat: the code I shared on github is actually quite terrible. Ignore the
code, look at the pretty charts

------
Blocks8
These simulations don't account for human choice on when they want to board.
There are customers anxious to get to their seats, and so listen carefully for
their zone boarding. There are customers who would rather spend time in the
terminal than extra time in an upright seat so they wait until the very last
minute to board, regardless of zone.

Increases in prices of checked baggage means many flights have more people
carrying bags on, due to limited overhead space, there is more incentive to
board as early as possible. If you don't have a carry-on that needs to go in
the overhead bins, the incentive to board on-time or early is lower.

Southwest airlines, mentioned here quite a bit, incentives customers to board
early (if you want a good seat, you need to get on early to choose it) and to
check in early (they can better gauge % checked-in because you are rewarded
for confirming with the airline 24 hours in advance). Their policy to allow
free checked bags is a nice courtesy but it also means more customer check
bags, reducing the time to store things in the overhead which leads to less
time at the gate. Free bags is a financial play, just not in terms of
additional revenue but as cost savings.

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epo
My experience (in the UK) is that the time is dominated by people being slow
to put their bags away, or putting bags away then blocking the aisle while
they take off jackets or getting bags back out to extract a book.

Also airlines tend to board from front and back simultaneously, which isn't
always an optimization as people join the shortest queue regardless of where
their seat is.

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shalmanese
Surely airlines can just do this empirically rather than rely on simulations.
Why not just A/B test a bunch of different boarding methods on different
flights and time what works the best?

~~~
bdunbar
Expense.

Every method of boarding will require training the flight crew, ground crews
at the airport. A non-trivial expense to change over from A to B. And then
back.

Departure times are measured down to the minute. Miss your time and much
activity downstream is affected - pax connections, gate use at destination
airport, flights downstream.

And so on. I'm sure that they do use A/B testing or something like that ...
but they do a whole lot of simulatin' first.

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TheFuture
Stop charging fees to check bags, and start charging fees for carry-ons.
Airlines should WANT checked baggage. And so should TSA.

~~~
uptown
Airlines LOVE baggage fees. They're tax free. I wouldn't be surprised to see
airlines reduce ticket fees and just boost bag fees for more tax-free revenue.

Reference this Hipmunk visualization: <http://visual.ly/air-travel-baggage-
fee-revenue-timeline>

~~~
underwater
Apart from the tax status, it seems that baggage fees are an effective way to
achieve market segmentation.

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huhtenberg
I thought the fastest was back to front, but alternating left and right side
for each row. In other words, board the _left_ side of last 10 _even_ rows and
the _right_ side of last 10 _odd_ rows at the same time, then let right/even,
left/odd people in, then move on to the next 10 row, etc.

There was a research paper on that few months ago, and it was on HN. Does
anyone remember details?

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rabbitonrails
How about this idea:

Much of the congestion is caused by people stowing their bags overhead further
down the plane than their seat, then having to reverse against traffic for X
rows to sit down. Also there is a large fixed time cost once the overhead bins
fill up and X passengers are forced to check their bags; they have to haul
them all the way to the front against traffic.

What if a system was installed at the security checkpoint that recorded
whether a passenger were boarding with a suitcase, and then assigned them a
bin overhead. The bins would have small LED screens that displayed the
passenger's name or seat number. An algorithm would match the bins to the
nearest seats, and reduce or possibly eliminate downstream luggage-stowing. It
would also be able to tell passengers that they were too late, the bins were
full, and they would have to check their bags.

Difficulties --

    
    
       * some bags are small or irregular, can fit 2 in a bin  (measure bag during X-ray?)
    
       * initially people won't understand the system leading to chaos

~~~
smackfu
Also people buy stuff at duty free, after the security checkpoint.

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davidu
Most of the fail to understand that people like to board in groups based on
association. eg, families like to board together. That mucks it all up.

Also, people are stupid and can't self-sort.

I must admit, Southwest's boarding always feels like the absolute easiest. You
just get in line by number and sit wherever you want.

~~~
mhewett
Regarding the mental qualities of travelers, I once witnessed this:

announcement: This is NOT a boarding announcement, please remain seated.

people: 80% of the people in the gate area stood up.

announcement: This is NOT a boarding announcement. When we do board, please
pick up a sack lunch from the cart near the ramp.

people: 50% started forming a line near the ramp. 30% remained standing.

announcement: Please remain seated. We will start boarding in about 15
minutes. As you board the plane, please take a sack lunch from the cart near
the door. Thank you.

people: Most looked around uncertainly and slowly sat down.

Person 1 near me: What was that about a lunch? Person 2: I don't know. I think
they may serve you a lunch, depending on where your destination is.

Me: Envisioning a scenario where the attendent gives you a lunch if you are
flying to Des Moines, but No Lunch for You! if you are continuing on to Los
Angeles...

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tocomment
Does anyone know why back to front boarding is slower than random? That's
doesn't make sense to me.

~~~
borlak
I'm assuming here just based on experience, but...you don't just go to your
seat and sit down, you have to put your bag in the overhead bin, which takes
some "aisle time".

in back-to-front, a line forms as you are waiting for people to store their
bag. one person can take up [block] 3 rows of seats while he is fiddling with
putting his bag overhead.

in random seating, people all over the plane are storing bags at the same
time, instead of just 1 or 2 people.

~~~
personlurking
I wonder what the percentage is of those delaying the line due to their
slowness vs. the need to search out space.

The most aisle time I've taken on any flight might be 10 seconds, though most
of the time it's zero since I prefer to store my carry-on below the seat when
I can.

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Eduardo3rd
I wonder how much plane size impacts the efficiency of system, particularly in
the case of the random boarding process? I flew on Southwest and American
Eagle last week and thought about this for a while. On Southwest people were
able to choose their seat based on their position in line, but that choice was
harder for some people than others. On American Eagle (pre-assigned seats) the
plane was so small (16 rows of 3) that they didn't bother with boarding order
outside of priority status. People randomly tried to get to their seat on the
plane, but it seemed like that was faster on a per-person basis than
Southwest. Perhaps choice slows the system down?

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mattst88
Conceptually back-to-front seems to make the most sense, but as the
simulations show it's still not efficient. So instead of plainly loading back-
to-front, load back-to-front but skip rows.

That is, if there are 25 rows on the plane, load rows 25, 20, 15, 10, and 5 at
once in that order, and in the second wave load 24, 19, 14, 9, 4, etc. That
way, the people sitting in row 25 will have a 4 row buffer between them and
the next passengers to wait while they get seated and aren't blocking the next
group (in row 20) from being seated.

Does that seem reasonable?

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matthewowen
When I board planes I wait until the last possible second - I like to hear
'last call' before I join the queues. I don't take stupidly big carry on
luggage, so why would I care whether I get on first or last?

I'd rather wait as long as possible and avoid being sat on the plane.

This probably ruins carefully planned boarding procedures. C'est la vie. But
as it stands, the trouble with boarding is that there are plenty of people
like me.

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omegant
I would like to see real boarding times, also It would be nice to see the
effect that all the bigger baggage (due to the baggage fares) that it is
carried aboard. This is one of the biggest drags when boarding, even more with
a full airplane as the last 20 pax are not going to find enough space for
their hand luggage anywhere.

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chrpes
Beeing sorted into groups and numbers actually make's me feel like cattle
instead of an airline passenger. I like the random boarding of Southwest and
most European low-fare carriers.

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Rhapso
It does not help that a lot of American companies do not use any of these
methods, they use front to back in sections.

~~~
RandallBrown
I can never understand the planes that board front to back. It makes
absolutely no sense at all.

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Kilimanjaro
Easy. Next time you buy a fleet, ask Boeing for planes with 10ft wide
corridors instead of 2ft.

