One year after releasing Scout, a tiny ADS-B receiver manufactured by uAvionix, ForeFlight unveiled the follow-on product at EAA AirVenture this week. Sentry is larger than Scout but also packs in a lot more features, including GPS, AHRS, and even carbon monoxide monitoring. At $499, it’s a compelling package.
Weather and traffic
It seems like table stakes these days, but the subscription-free weather and traffic available with Sentry is still the most important feature. Just like a Stratus or GDL 50, there’s nothing more to do than mount it and turn it on. Sentry connects to your iPad via WiFi, and accommodates up to five devices. Simply open ForeFlight and you’ll start receiving the full list of ADS-B products, from radar to METARs to PIREPs.
Reception seemed good in our test flights – we had weather at about 500 ft. AGL around Sporty’s, and updates came in reliably. With the full ADS-B network built out now, details about reception are less important than they once were. In fact, ForeFlight no longer reports the number of towers you’re receiving, only the overall quality.
We also tried the new Glance feature in ForeFlight synthetic vision to locate nearby traffic. It’s pretty slick.
GPS and AHRS
Two important features Sentry has that were missing from Scout are GPS and AHRS. The addition of these two – plus a built-in 12-hour battery – makes Sentry a complete iPad accessory, driving moving map screens, terrain alerts, and a full synthetic vision display. ForeFlight shows a handy setup screen the first time you connect, which ensures you get it mounted properly:
Tapping the SETUP SENTRY button brings up a second page, which offers three choices for mounting location: left window, dash, or right window. Then there’s a button to zero pitch and roll on the attitude display.
Sentry is the first ADS-B receiver to include a carbon monoxide detector. This will be most helpful for piston airplane pilots in the winter, since many cabin heating systems are susceptible to exhaust leaks and potentially serious CO poisoning problems. The middle light on Sentry is for CO – it’s green when normal, yellow when CO is above 35ppm and red when CO is above 50ppm. There’s also an audio alarm and a pop-up alert in the app.
We tested this using a car exhaust system and it works. The alarm is loud enough that you would probably hear it in the cockpit, and the app alert is also quite noticeable. We didn’t see the CO value change in ForeFlight until it alarmed (it stayed at 0 in our testing until going straight to 1000), but after a few minutes the light on Sentry did turn red and warn us. That’s what counts, and we think this is a nice addition.
Sentry is designed to work with ForeFlight, so complete status information is available in the app, including battery life, GPS status, and various settings. Firmware updates are also easy to do directly in the app.
Sentry is now available for $499. It includes a charging cable (no wall plug), carrying case, and a suction cup mount. The mount has a quick-release mechanism so you can connect Sentry to the mount in about a second. It’s intuitive and easy to do. There are no options for external antennas, so you’ll need to mount it on a side window. Sentry charges using a USB-C cable, which is a rugged and increasingly common choice.