A Comparison of Sleep and Performance of Sailors on an Operationally Deployed U.S. Navy Warship

The crews mission on a deployed warship is inherently dangerous. The nature of the job means navigating restricted waters, conducting underway replenishments with less than 200 feet of lateral separation from another ship, and various other operationsall of which require a high level of training, alertness, and attention to detail. Performing these tasks when sailors are sleep deprived creates the potential for catastrophic incidents that can cost millions of dollars and possibly result in injury or loss of life. This study compared the sleep and performance of sailors standing either the 3/9 or 6/6 watch rotation on a deployed warship. Results showed that not only did sailors standing the 6/6 rotation receive less sleep, but their response speeds were significantly slower than their 3/9 counterparts. Although the 3/9 participants stood half as much watch, with twice as much time off watch, they still received only 391 minutes of sleep per night, on average. Even more concerning was that the 6/6 participants received only 330 minutes of sleep per night (less than six hours per day), on average, accruing over 2.5 hours of sleep debt per night. Sleep provides a combat edge to todays warfighters. Leaders neglect it at their peril.