I thought dot matrix printers were the fastest

Here's another reason. Basically the mainframe software that runs a lot of the dispatch/gate processes is pre-historic. So they'd have to spend a lot of money re-coding it to actually generate the Postscript output that a modern laser printer needs to render pages.

"the printer" isn't just for the passenger manifest, but there's lots of other business processes, maintenance documents/releases, etc., that are printed from it on a rather time sensitive basis. With the sort of "change management" processes that are in place at a modern full-service airline, it would be an enormous undertaking to re-do literally everything that has been developed the years on the 'legacy' systems, train everyone, have a roll-out, etc. Its just cheaper to buy dot matrix printers and carry on the existing systems. Airline IT tends to move at a glacial pace, and most customer service graphical "terminals" are just front-ends, fancy or often not-so-fancy, for old mainframe applications.

Also, believe it or not, there's still outstations in which not much connectivity is available. An entire airline check-in and boarding/dispatch documentation generation operation for an outstation with the terminal emulated systems and CRT-attached printers, can probably run 5-10 check-in stations on a 9600 baud modem. Not that expensive of dial up circuit through an international carrier for the few hours a day it might be needed. But if you have the modern fully graphical stuff, that requires a lot more capacity that may very well only be used once a day.

There is no specific requirement to use dot matrix printers or indeed, any type of printer. You can generate flight paperwork on the back of a paper napkin in crayon if it meets the required standards for information. Unfortunately, paper copies are still required by most jurisdictions though so electronic data transmission is supplementary rather than statutory in most cases.

Is it because the noise is cool?

Plus if you're doing multi-part paper and the ribbon is dead, you only lose the top copy (and even that's often readable if you hold it at an angle) and the others are all fine.

Slowest.

The cost of ink ribbons is practically free compared to toner.

http://www.itweb.co.za/mobilesite/news/128514

Which is at the range of a nice desktop laser. It's far below the office-level laser printers.

Furthermore, in my experience those high speed dot matrix printers do not have a normal head that goes back and forth, but rather the "head" is an immobile line of dots that goes all the way across the page while the paper scrolls up past it. While it's the same technology it's not what people think of as dot matrix!

This is my preferred explanation so far :cool::D

Does anyone have statistics on reliability of dot-matrix vs laser vs inkjet vs other technologies? (FWIW it's not just airlines, the CA DMV seem to enjoy their dot-matrix too.) I can imagine that's a major factor here, assuming they don't want to regularly delay flights because the paper jammed yet again.

For what is worth, when I worked IT for a TV station, we used laser printers to print scripts for news broadcasts. They were mission critical and time sensitive, and it was not unusual for us to print well over 1,000 pages per day, every day. High quality laser printers are tremendously reliable when properly maintained and when used with the correct paper (which is a often neglected part of the equation).

Having said that, so is dot matrix ... I'm in the "why fix something that isn't broken?" camp.

I've got to think most of the reasoning has to be because of interfacing with software that in general is really old. Dot matrix printers in general you could pretty much just dump the characters that you wanted printed out the parallel port and the printer would produce that output. No drivers or anything. In general, lasers and ink jets require more processing, and you're not just sending raw characters to the printer. Course, in general they're more capable of printing graphics too because of that, but that's not likely a need for the airlines.

Being able to load up a whole box of paper instead of unwrapping reams probably doesn't hurt either.

I'm assuming these are still in general parallel port driven, which means the parallel port continues to live well past when the manufacturers started to try killing it off.

Actually, there are at least a few (comparatively) inexpensive software applications ("middleware") that can be installed on a server and intercept the print stream, repurpose it, and output it to any number of technologies.

I did a project about 10 years ago for a very large national grocery store chain. Our software sat on their network and "pretended" to be a printer. All of their mainframe print for 5 production print centers was rerouted to this application, which looked at the print data, determined what the format/layout should be - based on the content of the print data, reformatted the data as needed to output to print and/or email and/or archive and/or document management system and/or bit bucket. The software was able to make decisions based on the content of the print data and determine whether it was looking at an order summary, or a warehouse inventory, or a payroll check/deposit advice - and decide which specific printer on the network to print to.

The beauty of a system like this is that no changes need to be made to the upstream system. No need to drag COBOL or Fortran programmers out of retirement. No need to spend time and money trying to find people who have actual real-world experience with PSF programming, or other mainframe OUTQ configuration tools.

And the best part? The total cost of the solution - including roughly 500 man-hours of installation/configuration/testing was under $150k. Obviously something like moving all gate printing to a central system like this would cost more than that, but it would likely ROI in a very short time.

That said, the benefits of fan-fold paper for applications like this are hard to replicate with laser print. You would need a higher-end HP, or a workgroup class Lexmark/Xerox/Canon/Ricoh/etc printer with an integrated stapler/finisher. Putting one of those at *every* gate in the system would be very expensive to roll out, and those systems tend to require more maintenance than line printers, and to go down hard when they go down.

(The above comes from 30 years experience in the copier/printer industry - as a service tech, a systems analyst, a solutions implementation engineer, etc, etc, etc)

Actually, a lot of this class of printer are serial connected, rather than parallel. Serial cables can be longer - up to 15 meters, compared to a max of 15 feet for parallel cables. They also use more compact connectors and can be extended via serial to RJ45 (ethernet) adapters, which can stretch that maximum distance up to 45 meters. Many of those little line printers are also capable of connecting directly to an ethernet network.

Sorry if this was only interesting to copier/printer geeks....