Hard to believe that an airliner could be jeopardised by a spilled coffee. Which of us here has not at some point spilled coffee or water on a keyboard (or had someone else do it for them).
More than anything else I am baffled as I would have expected avionics to be reasonably spill-proof or else for drinks to be banned from the cabin. It strikes me as an easily forseeable situation, and the people who design airliner cockpits are not stupid.
Was this a hazard to previous generations of airliners? Is it something that we should be worried about in our smaller aircraft?
I think this is inevitable unless the switches and displays are sealed to IP67 or better, which normally they won’t be because it drastically restricts the choice.
You can get sealed toggle switches easily – milspec for c. $100, or perhaps $300 with aviation paperwork. Push button switches similarly are available but mostly in a round button form – like the PTT switch on the yoke. Rocker switches are harder; they do exist but don’t feel good, due to the rubber membrane. Displays can be sealed easily.
But if you look at say this piece of a 787 cockpit
it doesn’t look like most of it is sealed. The pushbutton switches especially don’t look panel-sealed.
If switching a small current, filling a switch up with coffee could be a whole load of fun 
But these incidents suggest there is something more. Maybe shorting multiple switches/controls triggers some software issues, or the wiring behind the panel is open and liquid ingress does really unpredictable things.
I’ve built a lot of kit over many years which had to be watertight (IP68 basically) and it can be done but you don’t get nice feeling switches and buttons, regardless of how much you spend.
Thanks, that’s an interesting comment. Perhaps in the old days avionics would have failed more gracefully than more integrated digital systems we have today.
I had always imagined airline captains being given their coffees in first class china, but perhaps they’re destined to use these in the near future:
Airbus branded, of course.
In fact, one does not necessarily need IP67 to protect the MCDU from spilled coffee, as the orientation of MCDU vs. effective gravity remains more or less the same, and the amount of spilled drink is quite limited. For example, my Thinkpad notebook has a spill-proof keyboard – a small amount of liquid spilled on it would just flow through two drain holes and drip out the bottom of the notebook, but submerging it or pouring a bucketful of water in one big splash would certainly kill it.
Somehow I doubt this stuff is designed like a modern laptop
I reckon the switches etc is just bog standard stuff from Honeywell, who have bought up just about everybody who makes bits for expensive planes.
