(Deployed from the submerged submarine USS Providence, the NRL developed XFC unmanned aircraft is vertically launched from a 'Sea Robin' launch vehicle. The folding wing UAS autonomously deploys its X-wing airfoil and after achieving a marginal altitude, assumes horizontal flight configuration.)

It was a clear day on the Atlantic this week, with relatively calm seas, when what appeared to be a buoy suddenly popped up from out of nowhere.

The curious object bobbed about on the surface for a bit and then, responding to an unseen command, blasted a metallic device high into the air.

Just moments after its launch, the device unfolded a pair of wings, gained altitude and began to buzz through the sky - taking live video for hours and sending it back down American sailors hidden underwater in the USS Providence submarine.

This week's launch of the eXperimental Fuel Cell Unmanned Aerial System (XFC UAS) was the culmination of a nearly six-year effort by the Naval Research Laboratory to launch a drone from a submerged submarine. The buoy that floated to the surface, which contained the drone, was actually fired from the Providence's torpedo bay.

"The successful submerged launch of a remotely deployed UAS offers a pathway to providing mission-critical intelligence, surveillance and reconnaissance (ISR) capabilities to the U.S. Navy's submarine force," the NRL said in a statement Thursday.

Dr. Warren Schultz, program developer and manager at the NRL, said the drone is an example of how the lab works with the industry to "meet the needs of the special operations community."

According to the Navy, the drone flew a "successful several hour mission" before landing at Naval Sea Systems Command Atlantic Undersea Test and Evaluation Center in the Bahamas.