Sentry Plus is an update on Foreflight’s electronic conspicuity device but it can also do a lot more
Ian Seager
26 July 2022
From $799
Planning and navigation apps have revolutionised the flying experience for most of us, but add an external receiver of some kind and the experience gets even better.
Sentry Plus from ForeFlight is the latest receiver to be released, and it brings with it a host of features, some of which benefit those of us flying in the UK and Europe.
To put the Sentry Plus (which looks very much like a bigger, but still very portable version of the SE2 from uAvionix) in context, a little over-simplified history might be useful.
In the US (actually the best place in the world for General Aviation), the FAA uplink a Flight Information Service Broadcast or FIS-B is for short.
It brings weather and dynamic airspace information into the cockpit, and although you have to pay for the receiver, the data is free, and for any kind of cross-country flight the information is invaluable.
In the UK, despite a few small scale trials and plenty of words promising bigger trials, we currently have pretty much nothing in the way of uplinked weather.
But it’s not all bad. Those flying in the US got an ADS-B mandate, while in the UK we got CAP1391, which paved the way for lightweight low-cost electronic conspicuity devices, and a generous grant that brought us the SE2 from uAvionix, PilotAware and several other similar devices.
We’re happily emitting and receiving a variety of Electronic Conspicuity (EC) protocols giving decent traffic information in the cockpit, but as I mentioned, we have no weather, at least not yet.
ForeFlight, the dominant app in the USA, has just released Sentry Plus, the latest receiver to bring data and other benefits to the cockpit. It’s bigger than the uAvionix SE2 (and is indeed built by them), but still mounts easily via the supplied suction cup.
Unlike the SE2 in the UK, it is a receiver only, so does not transmit a CAP1391 compliant ADS-B position, but it will receive FIS-B weather and both flavours of ADS-B (1090 and UAT).
It will also receive and decode FLARM, although like most other applications that requires an additional annual fee, in this case £25 + VAT.
“It contains a carbon monoxide (CO) monitor that will warn you of excessive levels of CO in the cockpit – before it’s too late…”
Sentry Plus only works with ForeFlight, and in addition to providing the WAAS or SBAS position, it also has a backup AHRS which will provide both pitch and roll information for ForeFlight to display in case of an instrument panel failure.
Additionally it contains a carbon monoxide (CO) monitor that will warn you of excessive levels of CO in the cockpit before it’s too late! It comes with an 18-hour battery, a built-in G meter and, unlike the SE2, an external OLED screen for displaying things like g.
Sentry Plus is also a data capture unit so you can review your flight, and if you happen to be flying in an area with FIS-B data, it will also store that so that you can replay some of the graphical weather.
There are a couple of significant improvements, such as auto on and off (hands up if you have ever inadvertently left your SE2 or PAW running?), and although this won’t apply to most of us, if you happen to have onboard WiFi, it has WiFi client support.
So, should you buy one? As mentioned above, Sentry Plus only works with ForeFlight, so if you aren’t running that, the answer will be ‘no’ (30-day ForeFlight trials are available).
If you are running ForeFlight, the answer is ‘yes’ (on the assumption that you are already emitting some kind of EC).
The integration is smooth (firmware updates are elegantly handled from within ForeFlight), and the additional benefits of dual ADS-B plus Flarm, plus a standby AHRS and CO monitor coupled with the 18-hour battery life make it a great addition.
Now, let’s keep asking the DfT and the CAA for those FIS-B trials, shall we…!