The U.S. Navy grounded its fleet of 14 Northrop Grumman MQ-8B Fire Scout unmanned helicopters following the recent crash of an aircraft in Afghanistan and a ditching at sea. The Naval Air Systems Command (Navair) said it is reviewing Fire Scout system performance and operational procedures.
Loss rates of U.S. military unmanned platforms are not often discussed, but official data from the U.S. Air Force Safety Center reveals that a total of 79 General Atomics MQ-1/9 Predator/Reaper fixed-wing UAVs have been destroyed in accidents, with another 21 seriously damaged. The Air Force acquired 248 Predators and 156 Reapers through the end of Fiscal Year 2011.
Navair said an MQ-8B operating in northern Afghanistan crashed April 6 while conducting a routine surveillance mission. The NATO International Security Assistance Force (ISAF) said initial reporting indicated there was no enemy activity in the area.
On March 30, an MQ-8B Fire Scout operating from the guided missile frigate USS Simpson was ditched at sea on purposeafter it had returned from a maritime surveillance mission in support of Africa Partnership Station (APS), Navair said. APS is a security cooperation initiative of U.S. Naval Forces Europe-Africa and several African nations. Navair said the unmanned rotorcraft failed to “lock on” to its automated recovery system. “After multiple approaches and exhaustive troubleshooting by operators, the aircraft was positioned a safe distance from USS Simpson and the flight was terminated. Subsequently, the Simpson crew performed a nighttime recovery of the aircraft,” the command said.
The Navy previously suspended flight operations and placed operating restrictions on the Northrop Grumman UAV in August 2010 after an MQ-8B lost its communications link and strayed into restricted airspace near Washington, D.C., then failed to return to base as programmed. Operators were able to restore control by switching to another ground station. The incident was blamed on a software anomaly. Another Fire Scout was lost over Libya last June during NATO air operations. That aircraft was apparently shot down.
Mishap rates for both the Predator and Reaper UAVs have fallen steadily with mounting operational experience. But the Class A mishap rate per 100,000 flying hours, averaged over the past five years, is still high: 5.05 for the Predator and 5.40 for the Reaper. Class A mishaps are currently defined as the loss of an aircraft or damage costing more than $2 million. By comparison, the same calculation for the Lockheed Martin U-2, a manned long-endurance platform that is difficult to fly, is 1.26.