US Army point if view from recent copy of AW&ST:
.......”Another concern is airworthiness. This was not an issue when UAS were purchased and delivered into war zones, but it became a problem when the service wanted to bring the systems home and train with them in domestic airspace.
The Army has three levels of airworthiness for UAS. Level 1 is the same as for manned aircraft and calls for a loss rate not higher the 1/100,000 hr. Level 2 is 1/10,000 hr., and is the minimum required if the platform is weaponized. Level 3, at just 1/1,000 hr., is the minimum acceptable level of safety, says Dave Stephan, associate director for technology with the Army’s Aviation Engineering Directorate. The Army’s most capable and expensive UAS,
General Atomics Aeronautical Systems’ MQ-1C Gray Eagle (pictured), is a Level 2 system—and that is for the kill chain, from sensor to operator to weapon. The air vehicle itself is only Level 3, which means the Army has to treat the Gray Eagle as expendable, “which is hard when it costs $10 million,” Stephan told the forum.
The reason for this low level of airworthiness qualification is historical. The Gray Eagle is a program of record, but many of the system capabilities and upgrades have been developed by the manufacturer and acquired outside the normal procurement system, he says. “Our legacy UAS were developed to meet urgent needs, and they have flight restrictions,” Stephan says. “Software certification is not possible, or too expensive, and propulsion certification may be in progress but will not meet Level 1.” They were not fielded with the intent of flying in U.S. airspace, and when it trains with these systems, the Army “accepts risk at multiple levels,” he says.
Future UAS is an opportunity to reset the safety bar and could have broad implications for industry. “Future UAS is expected to be Level 1 and to meet the manned safety requirement,” he says.
Industry is already grappling with how to certify commercial UAS, but progress is being paced by the types of operation the
FAA will allow. There is limited demand for certified UAS, while the FAA places strict limits on UAS operations. And the limits are unlikely to be relaxed until there are certified UAS. It is a chicken-and-egg situation the Army’s emphasis on airworthiness could help hatch sooner rather than later by raising the bar for UAS safety.“........