UAS integration into the NAS is a multi-faceted and ever-evolving challenge, which is why SC-228, Minimum Performance Standards for Unmanned Aircraft Systems, has over 500 members and is one of the largest committees within RTCA.
In September, SC-228 delivered four documents to the Program Management Committee (PMC). The first (DO-387 Change 1) is an update to standards for airborne electro-optical (cameras) used to detect and track aircraft, including those that may be flying without a transponder (i.e. non-cooperative). “Not only do UAS need to have onboard systems that can detect and avoid, which replaces a pilot in the air who could visually see what exists around an aircraft, but due to the practical limitations of cameras and the bandwidth challenges, the highly detailed images must be processed onboard the aircraft so that only a track is sent down to the traffic displays for the remote pilot,” said SC-228 Co-Chair Jim Williams of AURA Network Systems.
The second document (DO-365C) is a revision to the Detect and Avoid (DAA) MOPS that incorporated the EO/IR sensor and uses several classes of equipment to set standards for alerting and guidance through all phases of a flight. The third document (DO-398), which was originally a part of DO-365C, pulls out the topic of operations services, placing it into its own document so that the committee can continue to add operational concepts before equipment standards. “With the publication of DO-365C and the various sensor MOPS, we are proud to say that there are DAA standards for all phases of flight and for multiple categories of uncrewed aircraft,” said Brandon Suarez of Reliable Robotics, the other Co-Chair of SC-228. “This has been a community-wide effort for over a decade.”
The fourth document (DO-397) looks at existing gaps in navigation requirements for UAS, including at airports.
“A pilot today can navigate visually; but with a pilot on the ground, that ability goes away,” added Williams, who has also served as the FAA’s Director of the UAS Integration Office. “As of now, the only way to mix UAS at airports is to rely on visual observers and guides. The military does joint operations at their bases, and this can help inform what RTCA does in the future, as we look to situations such as cargo traveling via UAS from a busy hub to a small airport. As far as surface navigation requirements go at an airport, none exist yet.”
Williams continued that several companies, such as Reliable Robotics and Xwing, which use Cessna 208B Caravans to fly cargo, are interested in these requirements and have expanded their cargo operations to pave the way for remotely piloted caravans.
“Feeder cargo operations can be a very demanding use case that is ideally suited for the types of systems, such as DAA and C2 Links, that SC-228 is developing standards for,” said Suarez, “and RTCA is focused on improving the safety of the NAS, not just for UAS, but for all airspace users.”
What’s next for SC-228 is a Plenary on Oct. 7, where the committee will work to finalize its plan for upcoming standardization work to support airport taxi operations. Since two of its four missions are complete, it looks to the PMC to expand its scope so that it can continue to serve the needs of the industry, regulators, and aviation stakeholder community.
Members of SC-228 are also working closely with ICAO and EUROCAE to incorporate the concepts and technologies being standardized into internationally harmonized standards and guidance material. In December, SC-228 is expected to wrap up standardized lost link procedures ensuring predictability for aviation safety professionals, safeguarding that the airframe maintains a safe and predictable course flown, and certifying that aircraft manufacturers build products that could be utilized worldwide.