PARIS — Thales presented at the Euronaval trade show its work on a stealthy, multimission drone dubbed the Autonomous Underwater and Surface System (AUSS), a company-funded "black program" pitched at the French Navy and other navies.

A black program is one that is sensitive in nature and previously undisclosed.

The AUSS drone has a tapered nose, is torpedo-shaped with the standard 21-inch diameter, and is designed for anti-submarine missions, mine warfare and civil missions underwater and on the surface, Thales executives told reporters Oct. 17. That flush design helps autonomy. The company is in talks with undisclosed potential clients to design a full solution.

Thales spent three years, invested millions of euros, and teamed with 19 small and medium companies to build a prototype, which has undergone five sea trials at Brest, northwest France. The company combined its sonar and systems experience to develop the drone and will talk to more firms to add capabilities.

An AUSS drone is designed to carry payloads to collect sonar, visual and electronic data, and link up on satellite communication. The aim is to deliver an agile "pool dancing" device capable of a 360-degree turn, a speed of 17 knots and an emergency stop of 10 meters. Two weeks of mission is offered.

A key feature is to hold the drone stable out of sight just below the surface and extend a sensor mast for intelligence, surveillance and reconnaissance of activity on shore. That surface operation is a departure from the established underwater operations of Thales sonar activities.

"It marks the coming of age of the unmanned maritime systems industry in France," Pierre Eric Pommellet, senior vice president of Thales Defence Mission Systems, said in a statement.

In civil operations, the drone could be used for inspection of offshore oil and gas platforms and pipeline.

The "crown jewel" is a great deal of software intended to allow long-range and long-distance operation after deployment by submarine, ship or via the shore, a Thales executive said. That software underpins the autonomy that aims to allow the drone to "decide for itself" how to operate safely. Thales will work with naval shipbuilder DCNS to develop a means to fit the drone on ships and submarines.

Thales executives declined to comment on whether the drone might be fitted on the Barracuda nuclear-powered attack submarine under construction for the French Navy.