One aspect of my job that I love is being engaged in new industry trends and contributing to the discussions and ultimately decisions (in the form of policy) that arise in these areas. It does not pay well (or at all really) and it takes a lot of time, but I believe being actively involved in industry groups and initiatives is essential to learning and growing in the aerospace certification industry.
I’ve been a contributor in industry groups on DO-178C (member of the Model-Based subcommittee SG4 in WG-63/SC-205), RTCA Forum for Aeronautical software (FAS), Overarching Properties (I was explicitly invited by the FAA to become a member of the Overarching Properties Initiative), DO-254 (since 2007 I’ve been chairing the DO-254 User Group, which has authored several key papers that has driven policy), and now I am a key contributor to several key industry groups who are focused on certification aspects of UAS. (Keep reading to learn more about those groups and what they are doing).
Evolution of UAS
UAS, if you have not heard that one before, stands for Unmanned Aerial Systems. You might know these instead as UAVs (Unmanned Aerial Vehicles) or drones – same thing. Yes, they have been around for a while now. In fact, the first UAS were developed in the 1800s! (Think balloon aircraft). In our more modern era of UAS, these started out as complex craft for secretive military programs on one hand, and toys for children on the other. But over the past 10-15 years, UAS have evolved into a spectrum of vehicles from small to large, simple to complex, frivolous to essential, and everything in between. These UAS support surveillance, imaging, disaster relief, border security, delivery, and a host of other both essential tasks and just plain fun ones.
Redefining Risk, Safety, and Development Assurance
For UAS, the issue of regulating their operation to avoid risk is a top priority. But there is also the issue of development assurance to avoid risk of operational malfunction. If you recall, certification is all about risk avoidance, and when we talk about risk, we are referring to risk to human lives (primarily). That’s why large (transport) aircraft (CFR part 25) are treated as higher risk, need higher levels of safety, and therefore have higher development assurance requirements than small aircraft (CFR part 23) – because they have more impactful risk on human lives. So what is the risk to humans of these “unmanned” craft? Do we even need to certify them at all?
Of course, we do! A 50 lb. vehicle falling from the sky could kill someone on the ground. Thousands of package delivery vehicles flying over high density areas and in the national airspace could collide with objects, including other aircraft, and kill people both on the ground and the air. So we need to redefine what “safety” looks like in this new era of UAS.
Development assurance levels (DALs) have been driven by the concepts of safety and have defined the processes required for airworthiness certification. Demonstrating that an aircraft is built to safely perform its function is the purview of airworthiness certification. The FAA decided that small UAS operating within the safe guidelines do not need airworthiness certification, while those UAS outside that scope (both in size and operation) do. So, what are developers of these UAS doing to demonstrate airworthiness? What are they using as their certification basis?
The Policy is Emerging
Just as these UAS have evolved, so have the discussions and corresponding regulatory framework. But at least in the US, let’s just say the situation is fluid. While there is not a clear-cut standard or policy document one can look at to guide their development of UAS, this does not mean “anything goes.” The policy has been evolving in many different facets. The list that follows highlights some key aspects of the evolution of the regulatory aspects of the UAS over the past ~15 years.
- In 2006, the FAA issued its first drone permit and simultaneously began looking at ways to make drones safe and practical for recreational and commercial usage, examining risks such as interfering with manned aircraft or posing hazards to people on the ground.
- In 2012, Congress passed the FAA Modernization and Reform Act, which required the FAA to develop a comprehensive plan to safely accelerate the integration of UAS into the national airspace system.
- By 2015, the FAA had issued over 1000 drone permits. The rate of permit issuance tripled the next year.
- In June 2016, the FAA published the small UAS rule (Title 14 Code of Federal Regulations (CFR) part 107), which enables routine small UAS operations conducted with in visual line-of-sight (VLOS).
- In July of 2018, the FAA issued the roadmap document “Integration of Civil Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS) Roadmap”
- On September 18, 2020, the DOT published a document on “Type Certification of Certain Unmanned Aircraft Systems,” which states:
“The FAA has determined that some UAS may be type certificated as a ‘‘special class’’ of aircraft under § 21.17(b). The FAA will issue type certificates for UAS with no occupants onboard under the process in § 21.17(b). However, the FAA may still issue type certificates under § 21.17(a) for airplane and rotorcraft UAS designs where the airworthiness standards in part 23, 25, 27 or 29, respectively, are appropriate for the certification basis.”
- In April, 2021, the FAA released the Operations Over People rule, which further integrates UAS into the NAS and allows routine operations over people and routine operations at night under certain circumstances.
There is still a lot of work to be done to address the myriad of concerns around safety and development assurance of UAS. The FAA is typically driven by industry committee recommendations. Several committees are actively working on various facets of this. These include:
- SAE G-34/EUROCAE WG-114: Artificial Intelligence in Aviation
This group focuses on implementation and certification related to AI technologies for the safer operation of aerospace systems, such as vertical takeoff crafts, and assisted driving aircraft, intelligent pkg delivery, and the like. I am a member of this committee.
- RTCA SC-240/EUROCAE WG-117: Topics on Software Advancement
This group is working on a streamlined software development standard (leveraging/complimenting DO-178C) for use in lower risk operations, such as unmanned aircraft systems (UAS). I am a member of this committee.
- SAE S-18: Aircraft and Sys Dev and Safety Assessment Committee
This group is working on a document called AIR7121 “Applicability of Existing Development Assurance and System Safety Practices to Unmanned Aircraft Systems” with the intent of redefining “safety” and appropriate processes in the context of UAS. I stay informed as to what is occurring in this committee.
- EUROCAE WG 63 SG-1: Applicability of Existing Development Assurance and System Safety Practices to UAS and VTOL
This proposed working group will develop a EUROCAE report evaluating the applicability of existing development assurance and system safety practices to UAS and VTOL.
- RTCA AAM: RTCA’s first-ever Advanced Air Mobility (AAM) Workshop.The group looked at separation of standards, weather detection and avoidance, ATC ConOps concerns, vertiport standards, spectrum issues, enhanced/hybrid air traffic services, and qualifications of pilots and operators. The group recognized the work of SC-206: Aeronautical Information and Meteorological Data Link Services, as it relates to flight operations.
Each of these efforts are likely to produce industry sponsored documents that the FAA will eventually consider and perhaps adopt in establishing more formal means of compliance for UAS.
Until then, UAS systems are using a variety of methods to gain certification acceptance, including complying the with FAA’s G-1 and G-2 issue papers (IPs). The G-1 IP designates the applicable airworthiness and environmental regulations (that is, noise, fuel venting and exhaust emissions), including equivalent level of safety (ELOS) findings and special conditions, that must be met for certification. The G-2 IP provides a statement of the FAA procedural requirements, including those that define the applicant’s responsibilities for showing compliance. Specifically, how each applicant complies with these basic requirements varies.
In addition, over the past decade the FAA and EASA have made substantial progress in terms of harmonization of civil aviation policy. In terms of UAS harmonization, it’s just not there yet. This too is an area of evolution.
Need Help in this Rapidly Evolving Field?
Not only have I spent hundreds (or maybe thousands) of hours in UAS related industry committees, but I have also been leading the charge as a consultant and auditor for a large online shopping company who is realizing the vision of air-based package delivery. Through this engagement, I have been on the bleeding edge of certification in this very unique and exciting field. I have participated in the policy discussions. I have heard (and voiced) the concerns. We are still far from having a full and official development assurance policy/standard for all manners of UAS. But do not be fooled into thinking that means there are no requirements. There absolutely are! I have seen and been involved with proposed means of compliance for airworthiness certification. I have also seen what has and has not been accepted by the FAA. This is a complex and quickly evolving area of certification.
If your company is involved in UAS or eVTOL development and you need help in support of the certification requirements, Tammy@airworthinesscert.com. I’d love to hear from you and to assist as needed.