Garmin Announces Lower-Cost ADS-B Options
July 16, 2012 - Garmin announced today the GDL 39 portable ADS-B "in" receiver and the GDL 88 installed system that meets the rules for ADS-B out and also delivers full "in" capability, including subscription-free weather and display of traffic.
The GDL 39 is a small battery-powered unit that receives the free weather and other flight information being broadcast over the network of ADS-B ground stations the FAA is installing across the country. The GDL 39 uses Bluetooth to wirelessly connect to an iPad or to Garmin's aera portable aviation tablet. It can also be wired to some Garmin installed displays. The price is $799.
In addition to receiving the flight information service-broadcast (FIS-B), the GDL 39 can also show ADS-B traffic in some situations.
The GDL 88 is a complete ADS-B solution priced at $3,995. The system has a unique way to capture the code set in your standard transponder and send that code out over ADS-B. That is a critical requirement, because starting in January 2020 all aircraft will need certified ADS-B out and a Mode C transponder to fly in regulated airspace. But the rules require that you set the four-digit transponder code in only a single location. The GDL 88 resolves that problem by "listening" to the code you selected in your conventional transponder and broadcasting that same code over ADS-B "out."
To meet the rules the GDL 88 must receive position data from a GNS or GTN WAAS-capable GPS navigator. Garmin is offering a no-cost software upgrade to bring the WAAS navigators into ADS-B compliance. If you don't have a WAAS-capable navigator installed, the GDL 88 is available with an internal GPS sensor that meets the ADS-B rules, and the price for that system is $5,495.
Garmin engineers have invented a new way to display traffic position and possible conflicts using data from the GDL 88. Part of an ADS-B "in" display of traffic is a "stinger" line that shows where the airplane is going. Pilots can select the length of the stinger arrow to represent 30 or 60 seconds, or two minutes of projected track of the target. In other ADS-B systems the stinger line simply represents the other aircraft's path over the ground. But with the new TargetTrend system in the GDL 88, the stinger points to possible traffic conflicts with your track, and the stinger points toward the point of nearest passage with the other aircraft.
For example, on a conventional ADS-B display if you were catching a slower airplane ahead of you at your altitude, the stinger of that traffic target ahead would point forward in the direction that airplane is moving. But TargetTrend logic would calculate that you are converging on the slower airplane ahead and would point its stinger track back at you because you are coming into conflict.
TargetTrend logic is very useful when you are converging with other traffic targets at shallow angles. It can be difficult to visualize whether your tracks will merge, and how soon, but the TargetTrend stingers will point to the exact spot where you will come closest, or possibly hit, without a change in course.
If you have a GTX 330 transponder, or the GTX 33 that is part of G1000 installations, you can meet the ADS-B "out" rule by upgrading the transponder to "extended squitter" for $1,200. If you have a WAAS GPS navigator installed, that's all you would need to meet the requirement. ADS-B "in" remains optional.
The whole ADS-B rule and options are so complex that Garmin has created the ADS-B Academy and will be holding seminars throughout AirVenture. You can also study at the Academy by going to www.Garmin.com/ADS-B.