What doesn’t kill you makes you stronger — right?

Yeah. Right. But the United States Marine Corps take this idiom to a whole new level (per usual) of application in the following footage, where they simulate a helicopter sea crash in a “helo dunker underwater egress trainer” to ready 20 leathernecks for the deployment with the Marine Medium Tiltrotor Squadron 262 in Okinawa, Japan.

The training itself was conducted at Camp Pendleton in San Diego County, California.

The lengthy and altogether petrifying process teaches Marines who to escape a crash at sea, and an upside-down aircraft that is taking on/has took on an immense amount of water.

What makes the training that much more daunting (hard to believe it’s possible but … yep!) is when they interview a retired recon Marine who basically says yeah, even for me, who was essentially “drown-proof” going in, it was NOT doable the first time around.

According to the brave members of the USMC who go through the insane survival exercise, it’s all about technique and “finding reference points.” Egress, that is.

The squadron is more famously known as the “Flying Tigers.” They operate a fleet of MV-22B Osprey choppers and have, historically, been a part of some epic battles, including Khe Sahn in Vietnam and Operation Iraqi Freedom after the 2003 invasion.