Wanna know why the QRHs are coffee stained on the A320? It’s almost always because the coffee cup mouth opening is put in the aft position (pointing aircraft rear). As in when you look at the coffee holder, the 9’oclock position. That’s the worst place for takeoff or landing, especially takeoff. The coffee will tilt and then flow right out the hole. The best position I’ve found is to have the coffee opening point towards the window. So when you look at coffee holder, the 12’o clock position. I’ve never had ANY coffee spill with this technique.
Another offender? Guys who put their full new coffee in the cup holder with no lid. Bro, that thing is gonna spill.