The Dual XGPS 170 ADS-B receiver includes a soft rubber and dash mount and fits nicely on the glareshield.

The Dual XGPS 170 ADS-B receiver includes a soft rubber dash mount and fits nicely on the glareshield.

WingX Pro 7 users have a new wireless ADS-B receiver option, the Dual XGPS170. Developed by the same company that makes the popular Dual XGPS150 GPS receiver, the 170 uses Bluetooth to wirelessly send GPS position data and ADS-B weather and traffic data to an iPad or Android tablet running a compatible app. Right now Dual lists compatibility with WingX Pro 7, EFB from Global Nav Source and Reader Plates, though they say more apps will be added soon.

Portable ADS-B receivers are relatively new to general aviation, and are an inexpensive way to receive subscription-free weather in the cockpit on iPads and Android tablets. They receive the free ground-based ADS-B data broadcast, which contains local and national NEXRAD radar imagery, text weather reports, TFRs and in some circumstances nearby traffic. We took the XGPS170 on a flight today to test out its features and compare it to Stratus, the wireless ADS-B receiver for ForeFlight. Let’s first look at the  XGPS170 features and how it works.

Dual XGPS170 ADS-B Receiver

The XGPS170 was announced at Oshkosh earlier this summer, and is now available just before the holidays. The device is fairly compact, and includes a rubber dash mount that rests nicely on the glareshield of most airplanes. The mount also includes some suction capability, so you can place it vertically on a side window to keep the sun from baking it on a dark glareshield. It includes a small external flip-up antenna that can be adjusted to any angle, and can be removed if you want to add a remote wired antenna (one of these antenna options is required). The receiver uses Bluetooth for wireless data transfer, and can connect up to 2 devices simultaneously.

A physical switch is used to turn the device on into one of two modes: GPS or GPS/ADS-B. The GPS-only mode can be used when all you need is navigation data, conserving battery life. There are 4 indicator lights on the top/front of the receiver to indicate the status of the battery, Bluetooth, GPS and ADS-B reception. One thing that’s slightly confusing is that the ADS-B light will be on anytime the unit is turned on in ADS-B mode, regardless of whether you’re actually receiving ADS-B data or not. When receiving an ADS-B signal this status light pulses, though this is tough to see in bright conditions.

Dual advertises battery life of the unit as 5 hours, and the results from our flight test proved this to be fairly accurate. It includes a standard USB charging adapter with 12-28v cigarette lighter, and you can charge it at home from any standard USB wall charger.

In addition to receiving the standard FIS-B weather products, the Dual XGPS170 also receives limited traffic information. It includes a single-band 978Mhz receiver, so you’ll only get traffic information rebroadcast from ground stations or directly from other 978Mhz Out aircraft. And remember that traffic information is not continuously transmitted like weather; rather your aircraft (or one in close proximity) needs to be equipped with a certified ADS-B Out system to “ping” the ground station, which will then send you a customized traffic report. In other words, if you don’t have ADS-B Out in your aircraft, you probably won’t see any traffic with this box.

WingX shows external hardware information, including the status of ADS-B reception.

WingX shows external hardware information, including the status of ADS-B reception.

Flying with WingX Pro 7 and the Dual XGPS170

As mentioned earlier, the Dual ADS-B receiver is compatible with several apps, but the one most are probably familiar with is WingX Pro 7. This app was just updated a few days ago to version 6.9, which added support for the XGPS170 and a new SmartTaxi surface warning system. ADS-B weather display is not new to WingX, as it has supported the SkyRadar ADS-B receiver for awhile now.

To gauge performance we flew the XGPS170 paired with WingX Pro side-by-side with another iPad connected to the Stratus ADS-B receiver and ForeFlight. We flew locally in the Cincinnati area, where ADS-B coverage is excellent. Just after takeoff both systems indicated reception from two ADS-B ground towers at about 300′ AGL, just as expected. WingX includes a nice feature in the bottom left corner of the map that indicates the Dual’s battery life and how many towers it’s receiving from. At about 1,000′ AGL the Dual picked up 6 towers, while ForeFlight/Stratus indicated reception from 3 stations. While one tower is all you need, it did appear the 170 has slightly better ADS-B reception.

After about 5 minutes both systems displayed text weather and color-coded airport symbols on the map for airport VFR/IFR status, but WingX only showed METARs and AIRMETs on the text report display and did not display TAFs, while ForeFlight/Stratus showed us all text weather products. One confusing item when viewing text weather in WingX is that it alerts you in red at the top of the text display that “Internet Weather is 2 Hours Old,” though it’s actually current (updated by ADS-B).

The performance of the radar imagery in WingX was not up to par, showing significant gaps in the white shaded areas.

The performance of the radar imagery in WingX was not up to par, showing significant gaps in the white shaded areas.

The real disappointment with the system came with the radar display. The first thing to be aware of is that WingX defaults the overlay of areas not receiving ADS-B weather to OFF, so there’s no way for you to know if there is missing data or simply no precipitation in the area. Once we turned this setting on (called “Fade No ADS-B Areas”) we were surprised to see significant gaps in the radar display, showing limited local and national radar coverage. As a point of comparison the iPad with Stratus/ForeFlight was simultaneously showing the complete radar picture for the entire U.S.

Another problem with WingX is that the app crashed 4 separate times during the 60 minute flight on an iPad 3. In addition to the safety issues of relying on this for chart and navigation information, it became frustrating to have to wait 5-10 minutes after each crash for the next cycle of weather products to be received and displayed.

So what about traffic with the Dual? We flew for about an hour near the Cincinnati Class B and didn’t see a single traffic target. Our aircraft was not equipped with ADS-B Out so the only way we would have seen traffic is if we passed near another aircraft with a 978 MHz ADS-B Out transponder. As a point of comparison, the Garmin GDL-39 ADS-B receiver for iPad has a dual-band 978/1090 MHz receiver, so with that system you will typically see ADS-B Out-equipped airliners. And it’s fair to say at this point that the number of airliners with 1090 MHz systems far outnumber GA aircraft with 978 MHz ADS-B Out.

The Dual XGPS170 is available now for $799.

The Dual XGPS170 is available now for $799.

Conclusion

While there is room for improvement in WingX’s display of ADS-B weather, we really like the construction and features of the Dual XGPS170. The controls are intuitive and its compact size fits well in the cockpit. The battery life is just over half of that of Stratus at 5 hours, but that’s not really an issue since you can plug it in to a 12v outlet with a standard USB charger. Dual-band traffic would be a nice addition to pick up a more complete traffic picture, but honestly portable ADS-B traffic systems really won’t be of much value until more aircraft are equipped with certified ADS-B Out equipment.

The real weakness with this ADS-B system is on the software side, though. The radar picture was consistently incomplete in WingX, and the app was unstable. This is brand new and bugs are inevitable, but we hope to see improvements in WingX soon.

The Dual XGPS170 is available now for immediate delivery and retails for $799.

 

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