All 14 Fire Scouts, helicopter-like drones that are flown off the decks of U.S. warships, have been taken off duty, "while system performance and operational procedures are reviewed," according to a Navy statement.
That number dwarfed the total combined purchases of the Navy's other two unmanned drones — the Broad Area Maritime Surveillance drone and Small Tactical Unmanned Aerial System — over those five years.
Six new Fire Scouts were set to enter the service in fiscal 2013, according to the request.
The shutdown was first reported by Flightglobal and Wired's Danger Room blog. The decision came after the Navy lost two drones in the span of two weeks.
One drone was intentionally crashed into the ocean off the coast of West Africa.
Navy operators couldn't gain control of the drone as it prepared to land on the USS Simpson after conducting a surveillance mission near the African coastline on March 30. Unable to land safely, the ship's crew decided to crash the Fire Scout and bring the wreckage back to the ship, according to service accounts.
Another Fire Scout was lost last Friday during an intelligence mission in northern Afghanistan. Service officials could not confirm why the drone was lost or what it was specifically doing in that part of the country.
The last time the Navy lost a Fire Scout drone was during the United Nations-mandated peacekeeping mission in Libya last year. Government forces loyal to former Libyan strongman Moammar Gadhafi shot down the unmanned aircraft during those operations.
Prior to the crashes, the Navy had planned to arm the drones with a modified version of the Hydra rocket carried by the Marine Corps's Cobra and SuperCobra attack helicopters.
It would have been the first armed unmanned drone in the Navy's arsenal.
These latest incidents, however, mark a difficult time for the Fire Scout program.
The Pentagon slammed the "fragile nature" of Fire Scout's communications links in its review of the program last August.
The unmanned aircraft failed to take off from Navy decks on a number of occasions during flight tests held in 2009. Those problems were tied to the weak connectivity between the aerial drone and its control systems on Navy ships.
Northrop Grumman, the Fire Scout's prime contractor, at the time claimed the problems were fixed and said the drone has performed well since those tests.