Well, I think it measures the amount of water collected by extreme laughing about funny explanations towards the this little thing.
I'm really glad that Captain Sim implemented it.

We definitely need more such gauges on other planes.  ;D

Lets talk about the engine vibrations caused by joking passengers then ..
(I hope you get my strange humor, I don't offend anyone intentionally)


Getting more serious now: Has anyone of you ever tested the takeoff warning horn to come up?
Should be on the No.3 thrust lever and gets triggered if no flaps, no stab trim and speed brake lever not full forward.

I don't hear a thing when I do this but it's mentioned in the manuals.

Another question: Weren't the old manuals for the 707 coming in full color while the current ones are b/w only?