What does it mean to Rig For Red and what is is used for?

Answer 1

"Rig For Red" is a term used in the military to indicate that the ship or unit is transitioning to a nighttime lighting configuration, with only red lights being used to preserve night vision. It's basically like saying, "Hey, we're going incognito in the dark, so put on your red light special." It's used to maintain visibility during low-light conditions while minimizing the risk of detection.

Answer 2

The term "Rig for Red" is actually an older term, since most submarines today use broadband Blue lighting for night operations. Many spaces on older boats still have Red lighting, though.

"Rig for Red" is normally a command used in the Control Room. It is normally used when the boat is going to be surfacing or coming to Periscope Depth at night. The purpose is to give the lookouts and the officer designated to head to the bridge upon surfacing a chance for their eyes to adjust to darkness, or the OOD the same thing before looking through the Periscope. However, with the change to Blue, often times Red glasses are also used to provide the same effect and then Control is changed when the command is given to surface or come to PD.

During Battle Stations and at night, many spaces are rigged for red in order to simulate night conditions. While submerged underwater during normal operations, the only real reference for the time of day is the meal being served, since most boats operate on an 18 hour rotation and not a 24 hour rotation (6 hours on watch, 12 off). The red/dark conditions are more so people can sleep rather than to simulate night. Underway, the sleeping areas are always dark unless it's a cleanup day, a drill is going on, or Battle Stations has been sounded.

Though the sleeping areas are still configured for Red lighting, tactical spaces and the Control Room were changed to broadband Blue lighting in the 80's when it was determined that the color was easier on the eyes under normal working conditions over lnog periods. I always hated it - a lot harder to catch an undetected nap in the corner than it was when Red was used.