Betty – Voice Warning System

Updated: August 09, 2020

Betty is a simple and effective aural warning system, that is very common on military and commercial aircrafts. It is one of the most powerful tools to improve the situational awareness and reduce pilot’s workload.

Why “Betty” – Read here.

The system is very easy to configure and adjust for your preferences.

Betty is a simple Python script uses Raspberry Pi audio capabilities to playback pre-recorded audio files or  synthesize voice aural messages at the runtime.

At this stage the script is configured to playback attitude warnings (overbank and overpitch) and read back remaining fuel (endurance) on progressively reduced intervals as the fuel being consumed.

Please let me know if you have any suggestions for the warning messages.

In order to hear the aural warnings thee audio output of the Raspberry Pi should be connected to the intercom system. Some modern intercoms have an Aux input that automatically muted when PTT is activated. Older intercoms a passenger microphone input can be used with a simple impedance matching circuit.

You can download the most recent source code from GitHub:


Download the latest code from the Github (link above)

Create a folder for the code

cd ~

mkdir betty

Copy the downloaded code into the created folder


Install Pico TTS

optionally update your system first

sudo apt-get update
sudo apt-get upgrade

Install the Pico

Update August 2020: Littspico library has been removed from Raspbian distribution. It needs to be added there manually by running the following commands

wget -q -O- | sudo apt-key add -

echo "deb buster non-free" | sudo tee -a /etc/apt/sources.list

sudo apt-get update

Now, you can install the library as per normal

sudo apt-get install libttspico-utils


Configure automatic start-up for this Python script (run the script as a service)


First create a brand-new config file:

sudo nano /etc/systemd/system/Betty.service

Copy-paste the following text into the file

Description=Get Betty service running at boot



Enable the service:

sudo    systemctl enable Betty.service

Start the service

sudo systemctl start Betty.service

Check the status:

sudo systemctl status Betty.service