[Editor’s note: This is a guest post by Dr. Damon Lercel and researcher Hailey Manuel of Purdue University’s School of Aviation and Transportation Technology. They invite you to participate in a 10-minute survey, Electronic Conspicuity Technology for Aircraft Operating in the National Airspace System. The purpose of this survey is to gather insights into the opinions and concerns of aircraft owners and pilots regarding the potential requirement for electronic conspicuity technology (EC).]
What is electronic conspicuity?
EC is an umbrella term for technology that can help pilots, unmanned aircraft systems (UAS) users and air traffic services be more aware of what is operating in the surrounding airspace. Identifying an aircraft by electronic means involves the use of electronic devices such as ADS-B systems and other technologies to enhance aircraft visibility and situational awareness. EC includes devices installed or carried on board an aircraft.
The use of EC technology is often viewed as a key enabler of broader UAS operations and may increase the overall safety of the National Airspace System. EC strengthens the fundamental safety principle of “see and avoid” by adding the ability to “detect and be detected.” To be most effective, though, it requires 100% of users operating in a designated block of airspace to use compatible EC devices. However, barriers to the adoption of EC technology may include concerns about cost, privacy and regulatory enforcement.
FAA rulemaking and airspace implications
In the recent Federal Aviation Administration (FAA) Part 108 notice of proposed rulemaking (NPRM), “Normalizing Unmanned Aircraft Systems (UAS) Beyond Visual Line of Sight Operations (BVLOS),” the FAA proposes giving the right of way to UAS conducting operations under Part 108 unless a piloted aircraft is transmitting an EC signal, such as a compliant ADS-B technology or a proposed portable beacon.
UAS operating within Class G and some Class E airspace at or below 400 feet above ground level (AGL) would have the right of way over piloted aircraft not broadcasting an EC signal. Currently, the FAA does not permit ADS-B Out on most UAS due to concerns that a high volume of UAS transmitters would overwhelm the system and negatively affect the safety of piloted aircraft. The potential for saturating the ADS-B frequencies and blinding ground-based receivers is a major concern, as the current ADS-B system is not designed to handle the high density of signals expected from a vast UAS population.
Low-altitude risks and pilot visibility
Given that the NPRM proposes UAS BVLOS operations at 400 feet AGL and below, much of this low-altitude airspace is Class G, where UAS operations and non-ADS-B-equipped aircraft often coexist in the same airspace. The NPRM would require pilots operating non-ADS-B-equipped aircraft to avoid Part 108-compliant UAS traffic.
However, previous research has found that pilots are unlikely to see a UAS or, at best, have minimal response time to avoid a UAS. A study by Embry-Riddle Aeronautical University found pilots successfully detected an airborne drone only 30% of the time during the final approach phase of flight. This finding contributes to concerns over low-altitude midair collisions involving UAS and piloted aircraft.
Global approaches to electronic conspicuity
In response to these concerns, policymakers and technology developers have proposed various solutions. For example, the U.K. Civil Aviation Authority (CAA) has proposed technical requirements, equipage standards and operational use of EC to support the safe integration of UAS into U.K. airspace. The European Union Aviation Safety Agency (EASA) is exploring the use of ADS-Lite (ADS-L) as a low-cost solution for general aviation and other small aircraft to transmit their position.
ADS-L enables smaller aircraft to be detected by both other piloted aircraft and UAS, particularly in uncontrolled airspace, and is designed as an affordable alternative to more expensive systems such as ADS-B. This includes the development of mobile phone technology as an ADS-L solution.
Here in the United States, uAvionix has developed SkyEcho, a compact, portable ADS-B IN/OUT transceiver designed to enhance a pilot’s visibility and situational awareness in the air. By broadcasting the aircraft’s position, altitude, course and speed, SkyEcho can ensure that aircraft are visible to both ADS-B- and FLARM-equipped aircraft, greatly improving electronic conspicuity. The SkyEcho is a wholly self-contained, battery-powered electronic conspicuity unit and costs around $625.
Currently, SkyEcho is approved for use in the U.K., Australia and New Zealand.
Share your perspective
We would love to hear your thoughts on the use of electronic conspicuity. The survey is being distributed nationwide and is targeted at pilots and aircraft owners. There is no cost to participants, and individual results are anonymous. The survey results may contribute to a deeper understanding of the issues surrounding the adoption of electronic conspicuity technology, which can inform policymakers and technology developers.
Please reach out to Dr. Damon Lercel if you have any questions.
Click here to take the survey.
I would like a clear technical explanation for why the FAA assumes that these UAV systems cannot incorporate adequate see and avoid technology that now suggests to them it is in any way acceptable to abandon rights of way developed over a millennium of maritime and admiralty rights of way rules that have served us well in aviation. A Tesla in autonomous driving mode at 73 kts on a public highway can for the most part avoid traffic in a far more chaotic environment. A police speed gun using radar/lidar can discriminate in time to get a speeding ticket. The present proposal to abandon see and avoid responsibilities and abandon the promise the FAA made to us when they mandated ADSB equipage is completely unacceptable. The claim that the UAVs will overwhelm the inadequate ADSB infrastructure they promised they would build out is easily solvable without solving it on the backs of Part 23 aircraft operators.
A possible alternative solution would be to give the UAS folks a set of frequencies and have the FAA do what it promised: place sufficient ground receivers (possibly at the expense of the commercial delivery companies) to recieve and channel landline/alternative rf based signals to the ADSB network to permit identification on the present ads-b equipment installed in aircraft, such as the Lynx or Garmin systems.
The claim that the uavs will overwhelm the ADSB system is even more alarming. Is the density of these UAVs so high that not only can they not avoid fixed, charted obstructions, they will not be able to avoid each other. See and avoid is required of us, even in IMC and the rights of way are required when in VMC conditions. There is no excuse for these devices cannot be equipped with sufficient computer power and multi-spectral sensors to allow them to avoid themselves and more importantly, us.