12 May 2021
The merging world of Electronic Conspicuity is fast evolving its own laws, one of which states that all new pieces of equipment should offer something valuable without allowing the user to meet every single need. In this respect the Sentry from ForeFlight delivers.
Sentry is a dual band ADS-B receiver that also packs a WAAS GPS, a carbon monoxide detector, a back-up attitude source (AHRS) and a 12-hour battery in a small box that you can easily fit to your windscreen with the supplied mount.
What it doesn’t do is work with anything either than ForeFlight, pick up and decode FLARM or PilotAware, and most importantly for some, it isn’t a CAP1391 device for emitting ADS-B signals. If you are not thinking that it is pointless because of that, you’d be wrong (more on why later), but to find out just how it performs we took it flying from Wiltshire to Blackpool.
The first thing that strikes you about the Sentry is just how much it looks like a SkyEcho 2. To be clear it isn’t a SkyEcho 2 but it is made for ForeFlight by uAvionix, the people behind the SkyEcho, which is why the packaging and form factor are very similar. Like SkyEcho, Sentry charges its internal battery visa a USB-C lead, and like SkyEcho, Sentry attaches to your windscreen (other windows are available) via the enclosed RAM mount.
Sentry communicates with your iPad or iPhone (it only works with ForeFlight, and ForeFlight only works with Apple) via Wi-Fi (up to five devices at a time). So when you launch ForeFlight you’re automatically presented with a ‘SETUP SENTRY’ screen that guides you through the simple process, inviting you to tell it where you have to position the unit, and then allowing you to zero the pitch and bank angle for the AHRS calibration (this can be done repeatedly and in flight too).
Once that’s done Sentry just goes about its business in the background, displaying ADS-B traffic, providing a WAAS GPS position source, monitoring for carbon monoxide, and waiting in the background should you need to use it as a back-up AI (which is done in either split or full screen within ForeFlight (which, depending on your subscription level, will also provide synthetic vision).
The Department for Transport Electronic Conspicuity rebate scheme is currently running, helping buyers of qualifying kit to save up to £250 off the cost of a qualifying unit, but it us unclear at the time of writing if Sentry its included in the list of acceptable units. We’ve asked the CAA but not heard back, so if you’re considering buying one it would be worth contacting them.
The implementation of Sentry and the way it has been integrated with ForeFlight is very slick. If you are a ForeFlight user looking for an ADS-B In source along with its added features then you should buy one, but in the UK you should only so that if you are already emitting ADS-B by whichever means. Essentially I’m saying, sort your ADS-B out in whatever way works best for you, and then if you are a ForeFlight user, sorting your ADS-B In needs with Sentry is a great option.