Good article in DroneLife:
In case they passed you by without notice – and it’s quite likely they did – the May announcements that retail giant Walmart and Silicon Valley technology-disrupter Google are getting involved in the Automatic Dependent Surveillance-Broadcast (ADS-B) system manufacturing industry are being viewed as game changing by folks in the large-scale commercial UAV market, and with good reason.
In a nutshell, ADS-B is a real-time aviation data broadcast ecosystem that allows aircraft to send and receive critical location information. It is “automatic” in that it requires no pilot interaction, and it is “dependent” in that it requires transmission and analysis of aircraft data to work. The system is one of four components in FAA’s proposed Next Generation Air Transportation System (NextGen).
ADS-B systems feature two mechanisms, the foremost of which (for drone enthusiast purposes) is the ADS-B “out”, which transmits information about altitude, airspeed and location derived through GPS from an equipped aircraft (or potentially a UAV) to ground stations and to other equipped aircraft in the vicinity. Air traffic controllers rely on this information to “see” operating aircraft in real time.
The other component of the system is the ADS-B “in”, which is not included in the 2020 FAA mandate (requiring all manned aircraft be equipped with ADS-B out sensors by 2020). ADS-B in allows participating aircraft to receive air traffic and weather information from ADS-B ground stations and nearby ADS-B out-equipped aircraft. This information is displayed on a cockpit monitor to improve situational awareness.
So, what does all this have to do with drones? Well for starters, for companies like Google and Walmart that have visions of launching large autonomous fleets of on-demand delivery drones (similar to Amazon.com’s well-publicized plans), making the ADS-B technology more accessible (not only to their own interests, but also to the aviation industry as a whole) and robust is a true no-brainer, especially if it provides the added bonus of easing the minds of the regulators that will have final say on approval of these coming-soon drone delivery services. Fighting the good Public Relations fight is always important, especially so in dealings with government bureaucracy.
One of the highest hurdles currently to widespread adoption of ADP-B tech in the U.S. is that the price tag makes it a tough sell where regulatory agencies aren’t mandating its adoption. Why the Google and Walmart announcement carried so much weight in drone circles is that if Google can figure out a way to get the average cost of the hardware for a ADS-B system (current averages have this cost at $2,000 plus heavy installation fees, and the ADS-B out component alone can cost between $5,000-6,000 to equip an aircraft) down to around $500 or even lower, the system will be installed in many more aircraft.
So it’s really almost a “Win-Win-Win” for a well-funded and highly capable player like Google to get this done. Google wins by helping the industry meet its 2020 mandate for ADP-B adoption, showing regulators they are serious about airspace safety stewardship. Then its drone delivery fleet gets the regulatory green light and the rest of the aviation industry is happy because the company made meaningful investment in the industry, making the airspace safer for everybody.
Comments
I disagree. An affordable, on-board ADS-B in/out transponder with TIS-B is a simple, fail-safe method of sense and avoid. And heavy? The Sagetech transponder is 100g.
If you're going to relay from the ground, you need the following:
If you have an ADS-B out transponder on the UAS, you need:
The second is much more realistic - while the FAA has mandated ADS-B out by 2020, a lot of people have ADS-B in NOW, whether built into the instrument panel, or by way of an iPad app and ADS-B receiver.
Additionally, with ADS-B out, the UAS has the ability to request and receive ALL traffic targets, including legacy Mode C and even primary targets from terminal radar, and the ability to avoid them.
If the goal is to have UAS safely coexist, it's not about getting the FAA the data, it's about getting the other aircraft the data. To do that, you need to consider the systems that are already out there, in use, and how to work with them.
Of course, the real issue isn't with <200ft operations anyway. These will continue to be dealt with primarily by UOA NOTAMs. The real issue here is the integration of UAS above 2-400ft, as they work their way higher and higher into the NAS.
I do have to wonder what Google's motivation is for getting into this market, especially since the article reads like they'd be providing transponders for regular GA use as well. Certainly would be great, but I can't imagine their doing it out of generosity. Perhaps a component to be integrated with some kind of cloud UAS management offering?
UAVs already have all the information required by ADS-B at the ground control station. So there is absolutely no need for an expensive and heavy bit of electronics to be added to the aircraft. A simple, low-cost cellular data modem could send the information to an FAA cloud site much more reliably. Or a sat-modem if cellular is not available. This would also avoid the low-altitude problem of ADS-B (as I understand it, the ADS-B antenna coverage does not work below 200 ft).