The U.S. Navy has grounded its fleet of MQ-8C Fire Scout unmanned helicopters after two serious accidents within one week.
In one incident, a Fire Scout cashed during its final approach to landing at Naval Air Station Point Mugu in California. In the other, the Fire Scout was tied down — “chocked and chained” in Navy parlance – during a test, but the rotor blades still managed to strike the ground.
“Rotor blades ultimately came in contact with the ground causing blade separation and aircraft damage,” according to the official accident report.
Both accidents were listed as Class A, indicating damage in excess of $2.5 million in each case. However, no injuries were reported.
The Navy has declined to discuss the possible cause of the accidents or whether they may be related while investigations are ongoing. As a precautionary measure, all further MQ-8C flights have been canceled.
The MQ-8C, the latest iteration of the Fire Scout, is physically different to the earlier versions. The MQ-8A and B were modified from Schweizer 300 series small helicopters. The MQ-8C took the sensors and avionics developed earlier and mated them with a Bell 407 airframe which is twice the size, having a maximum take-off weight of 6,000 pounds. The RQ-8A first took off in 2000, whereas the RQ-8C’s first flight was not until 2013, and it was only delivered to operational units in October.
The Fire Scouts are used mainly for intelligence gathering, surveillance, reconnaissance and targeting missions, though there have also been experiments with armed versions involving the APKWS laser-guided rockets. One of their strengths, as with other unmanned aircraft, is sheer endurance: the MQ-8C can stay in their air for twelve hours at a stretch, abotu three times as much as the Navy’s SH-60 Sea Hawk. The Fire Scout is controlled by relays of pilots on the launching ship at a range of up to 150 miles.
This is not the first time we have been here. In 2012, the Navy grounded its MQ-8B Fire Scouts, putting them on ‘operational pause’ after two serious accidents. Those were more serious incidents, one crashing in Afghanistan while the other ditched at sea. The first accident was ascribed to a faulty navigation system, the cause of the other remains unclear.
The most alarming, though not the most serious, Fire Scout incident occurred in 2010 when operators lost control of an MQ-8B in Washington D.C. which then flew into restricted airspace. The problem was described as a software fault, and was resolved when operators switched to a different ground control unit.
“The operators did lose communication, but they were able to regain it,” Rob Murphy, the Navy’s team leader for Fire Scout, told a conference later. “The system operated like it was supposed to.”
The incidents did not shake the Navy’s faith in the robot helicopter. This was in contrast to a previous Navy program, the QH-50 DASH – Drone Anti-Submarine Helicopter— a small unmanned gyrocopter which proved highly effective. The QH-50 did have a high failure rate, mainly because it was only designed to carry out a single, one-way mission with a nuclear anti-submarine bomb, but supporters believe it was axed in 1969 because it was a threat to the funding of manned helicopters.
The MQ-8C Fire Scout should be able to survive the recent incidents. Paradoxically, these accidents highlight one of the great strengths of unmanned helicopters. While all types of unmanned aircraft tend to have higher accident rates than their manned counterparts, the consequences are vastly different. When a manned helicopter crashes, the commanding officer has to call bereaved relatives and arrange funerals, and can expect headlines in the news and years-long investigations. When drone crashes, it’s just a lot of paperwork, some hardware to replace, and the story will not make the front page even on the slowest news day. In a sense, unmanned helicopters crash because they’re supposed to.
The commercial world is very different to the military. While the Navy may be able to suck up this type of event, civil operators who are working on a slew of unmanned cargo and air-taxi drones are likely to demand very much higher standards of safety. And maybe in a few years they will have a few things to teach the defense sector when it comes to accident-free unmanned aviation.