I travel by air a lot, and at virtually every airport I've ever been too, including where you disembark by stairs, as opposed to by jet bridge, the left-hand-doors are always used; and the right-hand-doors are used for loading catering trolleys, etc. I understand why it would be useful to standardise this within a particular airport, but not between different airports. Is there any good reason for this? Conjecture is OK, but a verifiable answer would be best! :)

  • 7
    Once you set a standard all must follow until there is a good enough reason to do otherwise. Once you have servicing and support facilities set up at N airports with X aeroplane manufacturers, anyone who built ones that were mirror image would feel somewhat alone. Sometimes standards make no great sense. Where did the commander sit in the Space Shuttle? In a US military helicopter, which seat does the commander / whatever sit in? In NZ we drive on the left hand side of the road. If NZ was the pre-eminent military power on earth, which seat do you think helicopter commanders would sit in? :-) Commented Apr 23, 2013 at 2:33
  • 1
    The above comment is an answer. It's just that some people cannot recognise some answers :-). [Looks at it again. No. Can't understand the thought processes of people who cannot see an answer in that material. No matter]. Commented Apr 23, 2013 at 8:05
  • 1
    @RussellMcMahon, huh? Commented Apr 23, 2013 at 13:10
  • 5
    Andrew - I posted that as an answer. Some kind and helpful person converted it to a comment. I feel [tm] that the anecdotes re space shuttle and helicopters add perspective to why things happen as they do and are as they are. Once you get "critical mass" its hard to change. Once an industry does things a certain way you need to be very big to go against the standard. Commented Apr 24, 2013 at 12:33
  • Standardizing the side of boarding isn't followed in all industries. The Washington, DC Metro (subway) system is inconsistent with respect to what side of a train you board from - it usually depends on the station. On stations with an island platform, you board on the left side of the train. With stations with side platforms surrounding a set of double tracks, you board on the right side of the train. Commented May 6, 2017 at 21:45

3 Answers 3


Nate is correct, because the Galley is loaded from the right (and on a 737 is on the right hand side (centre for bigger planes)

Page 6 of the this PDF shows Boeing 747 design specs and how a plane is serviced while on the ground under normal circumstances. You'll notice that the cargo is also loaded on the right hand therefore if a plane was being unloaded via stairs it would create a substantial hazard.

  • 1
    All the answers here are good. I'm marking this one as correct, because it's the only one citing some evidence. Commented Apr 23, 2013 at 13:11
  • 1
    ... but this begs the question of why the cargo is loaded on the right side ;)
    – Jeff B
    Commented Jul 4, 2016 at 2:41

The "left" side of the plane is usually referred to as the Port side. The term most likely comes from terminology as used for Ships (Fore, Aft, Port, Starboard, Up and Down). I would say it is convention that ships dock such that the Port is on the left, from which the term for the side gets its name ("The side of where the Port is").

  • 3
    you're right: english.stackexchange.com/a/112115/3946 Commented Apr 22, 2013 at 18:57
  • 2
    It's not just coincidence... the reason it's called "Port" side is because that's the side where the vessel "ports"...
    – Flimzy
    Commented Apr 23, 2013 at 3:07
  • 3
    This is the more 'official' answer - the historical reason! +1!
    – Mark Mayo
    Commented Apr 23, 2013 at 3:28
  • 5
    Historical detail: the term "port" is NOT the English "port" as in harbour facility (though that word might be derived from it) but comes from the Dutch "boord", the side of a ship. Starboard is Englisised "stuurboord", "steering side", the side containing the steering wheel in a ship (in aircraft that's reversed with the captain on the port side, in helicopters the captain sits on the starboard side).
    – jwenting
    Commented Apr 23, 2013 at 5:45
  • 1
    @jwenting: Not that this is really the place to discuss this, nor is Wikipedia all that authoritative, but it does appear to disagree with you on the etymology of 'port'.
    – Flimzy
    Commented Apr 24, 2013 at 3:33

I expect it's because most airplanes are designed for boarding and deplaning on the left.

Next time you're on an airplane, take a look around as you're boarding. In my experience, the area around the boarding door on the left is relatively spacious and designed to direct passengers into the cabin. The corresponding space on the right is usually a galley. It would be less convenient for passengers to have to pass through the galley to board or deplane, and would interfere with the ability of crew to work in the galley (preparing drinks for oncoming passengers, or cleaning up after a flight).

  • 15
    From the pilot point of view, it is also simpler if the park procedure is the same from airport to airport.
    – mouviciel
    Commented Apr 22, 2013 at 14:05
  • 1
    And traditionally, the doors on the right would have not had folding stairs (in current production aircraft, those are usually not present at all). These days, they're usually less wide, just wide enough for maintenance crews to enter and load trolleys for the galley (the size of which is standardised internationally).
    – jwenting
    Commented Apr 23, 2013 at 5:42
  • @jwenting Lots of smaller turboprops still have the folding stairs. These aircraft are typically used by small regional carriers and passengers usually embark/disembark on the airport tarmac and walk to the terminal.
    – Johnny
    Commented Oct 13, 2014 at 17:13
  • 1
    @Johnny: Indeed. But the point is, those stairs are on the left and not on the right. Commented Oct 13, 2014 at 18:05
  • 1
    @NateEldredge indeed. If you look at older aircraft in fact, most have no doors on the right at all except maybe crew access hatches.
    – jwenting
    Commented Oct 14, 2014 at 1:52

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .