ATM Modernization, Business & GA, Commercial, Embedded Avionics

Space-Based ADS-B Q&A With Skip Nelson

By Woodrow Bellamy III  | March 24, 2015
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[Avionics Today 03-24-2015] In September 2014 ADS-B Technologies completed a 7,000 nautical mile (nm) public flight demonstration of its space-based Automatic Dependent Surveillance-Broadcast (ADS-B) Link Augmentation System (ALAS). The system has been flying since 2010 and the September flight demonstration proved its ability to deliver a 1090 Extended Squitter (ES) or 978 MHz Universal Access Transceiver (UAT) payload between an aircraft and a Surveillance System Delivery Point (SDP). 
Ahead of the planned full production version availability of ALAS later this year, Avionics Magazine caught up with ADS-B Technologies President Skip Nelson at the SATELLITE 2015 Conference & Exhibition last week in Washington, D.C., to discuss what the company has been working on and what it has planned for the coming year. 
Skip Nelson, President of ADS-B Technologies.

Avionics Magazine: Can you give us an update on what you have been working on since completing a 7,000 nm demonstration of dual-link space-based ADS-B in September?

Nelson: We’ve been working on miniaturizing or shrinking the size on the current device and adding additional side channels of information, such as uncompressed voice and data channels to the same basic connection; we’ve been testing that. We certainly learned during that flight demonstration that our technology has the ability to work in a range of different environments and transmit air traffic control data between the aircraft and satellite ground stations. Adding these additional side channels and uncompressed voice and data we feel can provide additional benefits for operators and Air Navigation Service Providers (ANSPs) on top of the core surveillance capability.

Avionics Magazine: How is the ongoing collaboration between ADS-B Technologies and Globalstar going?

Nelson: Our relationship with Globalstar and in particular, with their Chairman, Jay Monroe, has never been stronger. As of right now they have approximately 32 satellites available for our service. That covers about 75-80 percent of the world’s most important airways. They’re continuing to expand their system and to improve it.  They now have 24 of their Second Generation satellites in orbit. With these new satellites and upgraded gateways, they can now dramatically increase their speed from 9.6 kilobits per second (kbps), to 256 kbps. By way of comparison, that’s 25 times faster than their current speed and 100 times faster than Iridium’s First Generation systems. Our system was designed to take advantage of this speed and Globalstar’s bent-pipe architecture that supports very low latency, reliable and secure data transfer between the aircraft and an ANSP.

Avionics Magazine: How does your space-based ADS-B system help improve aircraft tracking and surveillance, which has been a big topic of discussion in the industry since the disappearance of MH370?

Nelson: Our system is designed to augment — not replace — ground-based ADS-B. It’s designed to work with any kind of ADS-B transceiver, both 978 MHz UAT and 1090 Extended Squitter. The system we have is unique in that respect; it’s not a new ADS-B system, it’s just a different way of getting an otherwise inaccessible ADS-B position report back to where it needs to be. The system is not designed to get an aircraft’s position from the other side of the world back to Miami Center for example. But it is designed to get an aircraft’s position to Miami Center within 2,500 nm from there. It’s a flight-information, region-centric sort of system, designed to work with individual regions to quickly and very reliably get the information back to where it needs to be. 

Avionics Magazine: What about the Globalstar SPOT technology? Can you give us an update on the development with that and how it helps improve aircraft tracking?

Nelson: We’ve had what I call breadcrumb-tracking devices available for many years. GPS trackers are very common. The iPhone has had a GPS tracker built into it for 7 to 8 years now. Globalstar SPOT is capable of giving you an aircraft’s position within a quarter mile to half a mile at least every two minutes. 

We can use a $99 SPOT tracker to solve this aircraft-tracking problem, as I explained during the IATA conference last summer following the MH370 incident. I know it works in an airplane because I flew one for 7,000 miles and it worked. But it seems like nothing is acceptable unless it’s very expensive or very complex, we continue to overlook the simple solutions that might save lives. Having said that, every device that goes in an airplane should be certified. I’m not preaching uncertified devices, but the technology is there if someone would just go with the efficient path and not worry about how much money somebody is going to make off a device. 

The goal for us is to make an economical, fully certified device and have it on the market by the end of the year. Who chooses to use it and what ANSPs choose to accept the data from it, that’s up to them and that’s a legislative, economic and ethical question. Do we want to track airplanes? Do we want another MH370? There are devices out there that will track an airplane within 20 Boeing 777 lengths if we really wanted to. 

Avionics Magazine: With what category of aircraft is your space-based ADS-B system designed to be compatible? 

Nelson: We’re doing General Aviation right now, as a [Research and Development] R&D demonstration of the capability. But the system was designed to work with Part 25 as well. It’s just a question of obtaining permission to test it on a Part 25 aircraft. In other words, it should work just as well on a Boeing 777 as it will on a Cessna 172. This is not a device that is attached to the skin or goes into the Line Replaceable Unit bay or into the cockpit. It goes in line with one of the aircraft’s existing ADS-B antennas and only requires a 2-amp circuit breaker. It’s relatively simple, inexpensive and easy to install. There’s no rocket science here. 

Avionics Magazine: You’re a member of the Equip 2020 Working Group, what are your thoughts on the 2020 mandate? Do you believe we are going to get all of the aircraft that need equipage outfitted in time?

Nelson: I think there’s still some denial out there. The FAA has given us a very reasonable timetable – more than 10 years to equip. All of the manufacturers and all of the potential installation agencies and repair stations need to get behind the 2020 mandate now because 2020 is coming up fast and I wouldn’t bet on an extension. Unfortunately, the aviation industry has a habit of waiting until the last minute, or until something goes wrong and then everybody scrambles for a solution.

Part 25 1090ES avionics appear to be tracking well, but we  need to give the owners and operators of the aircraft, especially Part 23 aircraft, a better range of avionics options. That includes entry level UAT OUT devices under $2,000 and more sophisticated 1090ES and Dual-Link 1090ES OUT/UAT IN devices for the heavy GAs, and the biz jets.

Avionics Magazine: What will be ADS-B Technologies’ focus with its space-based ADS-B platform for the remainder of 2015?

Nelson: We’ve already tested our final prototype so by the end of 2015 we plan to have a full production version; it’s going to be a little smaller, a little smarter and for the first time emphasis the secure nature of an aircraft’s position report over L-band. We’re also incorporating what we call ‘tamper-proof’ or immutable ADS-B capability within it. The device will be capable of using a proprietary algorithm that senses when ADS-B should be transmitted from the aircraft but for some reason it’s been stopped. One criterion might be that an aircraft has been airborne for two hours at 30,000 feet, and suddenly the feed to the antenna goes away. This device would take over and transmit its own backup ADS-B payload on battery power until it is shut down or the original problem is corrected. The goal is 100 percent accountability for all aircraft. We’re talking domestic, oceanic, and all over the world.

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