SmartASS-3 Air Speed Speaker

Easter 2011 was warm in Southern England. My aircraft, a Europa home-built, had sat on the tarmac for a few days in the balmy sunshine while I visited family and friends. With the fuel tank topped up and checks complete, I departed on the return flight. Takeoff was normal, as was the early part of the climb, but then the engine started to run a little rough. A few seconds later, it was running very roughly indeed and I was getting quite concerned. I checked fuel pump on & the ignition switch, all OK. Then, very clearly in my headset I heard "DING! VERY SLOW... DING! VERY SLOW..." and I knew it was time to stop worring about the engine and start paying attention to what really mattered. Airspeed! I pushed the nose down, picked a field ahead and landed (picture).

I have no doubt whatsoever that if I had not recovered the airspeed immediately that day, I would not be writing this now. At the height I was at, a stall would not have been survivable.

SmartASS Enclosure

The SmartASS-3 is an Air Speed Speaker, a talking Airspeed Indicator.

Using the auxiliary audio input of the radio/intercom system, the SmartASS-3 speaks airspeeds between 25 and 250 Knots.

The airspeed can be reported in Knots, MPH or KPH.

It also provides a 'speed director' mode that informs the pilot when the airspeed deviates from a target airspeed (perfect for nailing that approach speed).

The product features:

Inbuilt accelerometer
Speed director mode takes into account wing loading due to gusts or pilot pulling 'G'.
Acts as a 'stall margin preserver' to help the pilot maintain a safe margin above stall speed.
Undercarriage down audible alert
Provides audible alert on approach if undercarriage is not down and locked.
General audible alert
Provides audible alert triggered from external event.
Simple to install and use
A single combined volume control and push switch requires little panel space.

Take a look at the SmartASS videos page to see (and hear) how it works.

The SmartASS-3 Airspeed Speaker Installation and User Manual describes how this unique product is installed and used.

Many thanks to David Joyce for advocating the SmartASS-3 in his Stall/Spin article in the LAA magazine.

What you get:

To purchase a SmartASS-3, visit the shopping page.

Please note: the SmartASS-3 is not a stall warning system and it does not provide a stall warning function.

Powered Speaker Option

Powered Speaker Enclosure

The SmartASS-3 audio output is intended to be connected to an auxiliary audio input on the aircraft's radio/intercom so that the audio comes through the pilot's headset. It is also possible for the audio to be played through a powered loudspeaker located in the aircraft cockpit. This would be useful for low noise environments (e.g. in a glider or electric aircraft) and also for aircraft where it is not possible to connect the audio to the headsets.

Smart Avionics' powered speaker is small (102mm x 70mm x 36mm), lightweight (< 160 grams) and requires only 15 mA of current when idle.

SmartASS-3 Source Code

Smart Avionics is releasing the SmartASS-3 software source code in the hope that others may find it useful. It is free to use for any purpose but please note that it is provided with no warranty and no technical support.

If you have the right technical skills, it's straightforward to modify the code to change how the unit behaves and introduce new features, etc.

The source code can be found at This repository is kept up to date with respect to bug fixes and any other changes to the software.

Copyright 2005-2020 Smart Avionics Ltd.