The US Navy is reportedly returning to the use of celestial navigation as a back-up plan during potential Global Positioning System (GPS) attacks by hackers.
The navy is reinstating celestial navigation classes for all new recruits, enabling them to rely on the centuries-old practice to better serve the force in critical situations.
Naval Academy Department of Seamanship and Navigation deputy chairman Lieutenant commander Ryan Rogers was quoted by the Capital Gazette as saying: "We went away from celestial navigation because computers are great.
"The problem is, there's no backup."
The Naval Academy is currently teaching trainees to work with sextants, a reflecting instrument, which uses mirrors to calculate angles and plot directions.
The use of celestial navigation ceased in 1990s after the introduction of satellites with the capability to offer instant precision GPS tracking 24-hours a day.
According to navy spokeswoman, lieutenant commander Kate Meadows, the US Navy ceased all training in celestial navigation in 2006, but reinstated it in 2011.
Meadows stated that the navy is planning to bring the training back for enlisted ranks by the third-quarter of 2016.
Rogers said: "There's about ten years when the navy didn't teach to celestial.
"New lieutenants, they don't have that instruction."
The navy has also started pilot programmes in celestial navigation for Reserve Officers' Training Corps (ROTC) students at colleges in Philadelphia, Rochester and Auburn.
As part of its effort to combat cyber threats, the US Navy is developing a cyber protection system, called the resilient hull, mechanical and electrical security (RHIMES) system.
It aims to make shipboard mechanical and electrical control systems resilient to cyber attacks.