Pilot's Guide to Avionics 2011-2012 - 64

INS AND OUTS OF ADS-B
Continued from page 62

service-broadcast (FIS-B) . TIS-B sends out data with individual aircraft position reports for both ADS-B and non-ADS-B aircraft using data fed from the ATS system . FIS-B broadcasts weather and flight-information products, including Doppler weather radar images and other graphic weather products, plus sundry text products – NOTAMs, METARs, SigMets and more . The FAA approved two systems for satisfying the requirement for ADS-B Out, one with an altitude restriction, the other with a service constraint . The one without an altitude restraint is 1090 MHz Extended Squitter – essentially an enhanced Mode S unit . 1090ES not only has no altitude restriction, it’s also the standard internationally endorsed and is being used exclusively in Australia and several parts of Europe . The comparable systems in both Europe and Australia are

requirement, and it also provides ADS-B In, receiving both TIS-B and FIS-B . And, FIS-B is the weather service . A 978UAT or 978 MHz ADS-B transmitter satisfies the Out requirement – up to 18,000 feet . Flying above 18,000 MSL? Get 1090ES for your Out solution . In fact, another approach to getting TIS-B combines the 1090ES ADS-B Out solution, which gets TIS-B, with a separate 978 MHz ADS-B receiver to get the FIS-B . Completing an ‛All-In’ ADS-B System Satisfying the ADS-B Out requirement is actually pretty simple . The system needs the WAAS-enabled, approved GPS navigator linked to an ADS-B Out broadcast box, be it the 1090ES type or a 978 MHz Transmitter, or 978UAT . That’s it: a GPS nav source coupled to a broadcast unit . The GPS can be a blind unit working only for the ADS-B, or it can be a panel-mounted navigation source unit that (a) meets the applicable technical standards order and (b) can be linked to whatever Out broadcast box you chose . That satisfies the FAA requirement . Now, if you want to benefit from the free stuff, weather, traffic and the ability to directly “see” other ADS-B Out aircraft directly – you need ADS-B In capability; that can be either a 978UAT or 978 MHz ADS-B stand-alone receiver . Finally, you also need a display of some type to see the traffic and weather products . An aircraft operator already equipped with some form of traffic-alert or collision-avoidance system may not feel compelled to embrace ADS-B In; ditto for the operator or owner already equipped to receive satellite weather from one of the subscription-based services . But, for the thousands of aircraft lacking both – or lacking only a traffic-alert system beyond Mk .II EyeBall traffic detection – embracing both Out and In may hold interest . The total-system costs of Out and In solutions – even for aircraft lacking a display – are less than any of the stand-alone traffic sensors, which also need a display; adding In to your ADS-B package also is competitive with adding a dedicated satellite receiver . So, no weather-equipment charge or monthly subscription fees, a consideration that may be particularly attractive to pilots using a portable device to receive satellite weather datalink services . Now, these products – the traffic and weather – may be used only for advisory needs, the FAA points out, since there are system lags, and the weather images
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Where You Need ADS-B, per the FAA:
The ADS-B rule, like current transponder operating requirements, requires operators to have ADS-B Out avionics installed and operating by 2020, in order to fly their aircraft in the busiest airspace, as described below: Class A, B and C airspace. All airspace at and above 10,000 feet MSL (mean sea level) over the 48 contiguous U.S. and the District of Columbia. • Within 30 nautical miles of airports listed in 14 CFR §91.225, from the surface up to 10,000 feet MSL. Class E airspace over the Gulf of Mexico from the coastline of the U.S. out to 12 nautical miles, at and above 3,000 feet MSL. You should note that current transponder requirements are not changed or affected by the ADS-B rule. • •

compatible with our ADS-B equipment; that means what works here will work there . The 1090ES solution also works to receive TIS-B broadcasts from the network of ADS-B ground stations; it does not, however, receive the companion FIS-B signals . The altitude-constrained solution is the 978 MHz Universal Access Transceiver, or 978UAT . Considered a more-robust, more-flexible solution, a 978UAT works to satisfy the ADS-B Out regulatory

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Pilot's Guide to Avionics 2011-2012

Table of Contents for the Digital Edition of Pilot's Guide to Avionics 2011-2012