Dive! Dive! Dive!

Stock Phrase used on submarines or anything to do with something going down.

Examples of Dive! Dive! Dive! include:

Film

Madagascar: "Hoover Dam! We're still in New York. Abort mission! Dive, dive!"
Brian Blessed says in Flash Gordon "DIIIVEE MY HAWKMEN!"
All submarine movies have a dive scene: K-19, Hunt for Red October, U-571, USS Alabama, The Enemy Below ...
- Hunt for Red October also features an Inversion (Subversion? Sub Version?) of this trope, with a submarine doing an "Emergency Blow" of its ballast tanks to send the submarine rocketing to the surface to avoid an incoming torpedo. This sends a 100 meter submarine bolting out of the water like a breaching whale while stunned sailors on the surface look on. CAPTAIN'S SCARED THEM RIGHT OUT OF THE WATER!
Rob Schneider in Down Periscope. "Prepare for dive!"
One of the reasons why Das Boot is so great: it plays the trope straight then subverts it when instead of being saved by diving, the submarine is endangered by the fact that it's sinking.
In a deleted scene in Austin Powers in Goldmember, Dr. Evil tried giving these types of commands, parroted by Frau Farbissina, tilting the sub every which way, until an unnamed officer gave some real commands. Dr. Evil even said he did it out of love for Das Boot, "or as we call it in English... 'The Boot'".

The Bruce Dickinson song "Dive Dive Dive" is one long series of groan-inducing nautical Unusual Euphemisms for sex.

When the Wardog Squadron goes after Scinfaxi in Ace Combat 5, it initially performs an emergency submersion, but is forced to break surface and emergency-submerge again to fire its missiles. Eventually, Wardog squadron inflicts so much damage that when they try to dive again, they can't: it would sink the ship.
DIVE!DIVE!DIVE! HIT YOUR BURNERS, PILOT!!! The immortal introduction to a mission in Free Space 2 that starts with you in front of a huge alien Battlestar about to run you over.

U.S. Navy fast-attack submarines really do make this announcement when commencing a dive (though generally with less emotion, as it's a routine command).