Software release(s) 20160511 and later contain the ability to issue voice alerts. These are alerts, not commands or advice. Voice Alerts are an audio indication of local traffic and contain no advice on the action to be taken once the voice alert has been issued.
As the Pilot in Charge, it is your responsibility to take all necessary action. The issue of a PilotAware voice alert does not give information on all the traffic in the vicinity. It advises only on those that can be seen electronically, these being, PilotAware, ADSB, CAP1391, Mode C/S and FLARM if a FLARM mouse is connected. Additionally, if you are connected to an ATOM ground station uplink or a SkyGRID relay then you will be informed of Flarm equipped aircraft and Mode-S equipped aircraft will be converted to Mode-S/3D. There will be other traffic that is not being picked up electronically so it is important to continue to use your preferred visual scan for the primary device.
⚠️It is vitally important that you understand and acknowledge that there are concerns that reliance on a prompted lookout from any EC device, including PilotAware, could reduce the effectiveness of the visual scan.
For instance, there may be a danger that your attention will be focused on the one area prompted whether this is by voice or visually and therefore, you may be spotting the wrong aircraft, or missing other aircraft that are outside the area prompted by PilotAware.
Some pilots may become intrigued by the information provided on local aircraft, or fixated on the display or voice commands, at the expense of maintaining their necessary visual scan.
Pilots may also incorrectly assume that all aircraft can be seen on their EC devices. This is not the case for any EC device.
It must therefore be stressed that PilotAware does not replace the need for an effective visual scan which is your primary responsibility. If at any time you feel that you are distracted by PilotAware turn it off until you are more familiar with its operation. When in control of an aircraft, is not the place to learn how to operate any avionic device including PilotAware.⚠️
Voice Alert Output;
The voice alert output is available from the 3.5mm jack on the PilotAware unit. The PilotAware voice alert is not presented to, nor comes from your tablet or iPhone, although some navigational systems do incorporate their audio alerts.
The audio output from PilotAware should be connected to your intercom, 8.33 airband communications radio or other devices as you wish, using a 3.5mm male to male connecting lead.
Please note that the interface to your communications equipment will be bespoke to your installation and to your aircraft design. Information on connecting to the more common units will no doubt be available on the PilotAware Forum forum.pilotaware.com as more installations are completed.
Adjusting the Output Volume;
The voice alert software subroutine is always on. However, the volume can be raised or lowered as required to the maximum and minimum available. This is done by logging onto your PilotAware WIFI hotspot and typing in 192.168.1.1 or paw.local and selecting Configure from the Options Menu. Midway through the table, you will see the volume control.
Selecting ‘+’will increase the volume
Selecting ‘-’ will decrease the volume.
There is an upper limit beyond which the output volume cannot be raised. Above this further amplification will be needed if a higher output is required. The output impedance and other electrical characteristics can be found in the online Raspberry Pi literature. Modifications to the audio output of PilotAware Rosetta are not covered by the Warranty.
As the volume is increased or decreased an announcement of “PILOTAWARE” will be made so that you can vary the output for your needs.
Types of Audio Alert;
There are two types of Audi Alert given by PilotAware. These differ depending on whether the target is detected as a target with a GPS location (Target with a Bearing) or Without a GPS location (Bearingless Target)
Voice Alerts for Targets with a Bearing;
Targets with a bearing include PilotAware, FLARM, ADS-B (1090MHz), CAP1391 and Mode-S/3D. These all give positional GPS data so they can accurately position nearby targets. This allows PilotAware to give an audio alert very similar to that which you would get from an ATC service.
This voice alert is provided in the format; “Traffic, One O’clock, two hundred feet above, 9 Kilometres”
PilotAware will always call out the vertical separation in feet and distances in whole Kilometres rounded down to the nearest Kilometre. Audio Alerts will be generated when aircraft transit between 3 preset zones around the host aircraft. The zones are fixed but the horizontal distance at which you will get the first alert is configurable ie 10Kms, 5Kms, 3Kms or not at all.
In the phrase “Traffic, One O’clock, height, 9 Kilometres”, the reference to height will be followed by above, below or replaced by level if there is 0ft of separation.
Irrespective of what type of Electronic conspicuity signal is detected (GNSS or barometrically derived) heights are converted to GNE (reference 1013.2 mB) to minimise errors in separation.
With the latest 20220101 software, you will receive data from a significant amount of traffic that is detected directly, rebroadcast or relayed using the ATOM GRID or SKY GRID. This is fantastic but if you are receiving too many voice alerts it is suggested that you reduce the vertical and horizontal voice filters to 5Km for the first alert and 1000ft separation, or closer if you consider this appropriate for your style of flying. This will reduce the number of voice alerts you get but will not reduce the visual alerts. Making changes to the filters is done on the Configuration Page.
Voice Alerts for Targets without a Bearing (Mode-C/S);
Basic Mode C/S transmissions are considerably less accurate than modern systems, in that they give no positional information from coordinates. From the Mode-C/S signal received, only the target's height relative to 1013.2Mb (GNE) and the signal strength of the received transmission can be detected. So, the voice commands have to be in a different format from targets with a bearing.
The signal from an approaching Mode-S transponder will increase non-linearly as it gets close to, and diminish non-linearly as it retreats from your aircraft. As it gets closer, the strength of the signal received increases exponentially. The absolute signal strength at any particular distance is not a constant for all installations, so we can only work with the relative received strength and its rate of change.
A voice alert is generated as the signal strength changes from one user's pre-selected strength band to another. This results in the following voice alerts.
“TRAFFIC NOTICE” – Advises you of the presence of a Mode-S contact at the maximum range for your selected detection power setting.
“TRAFFIC ALERT” – Advises that the aircraft is continuing towards you. You should now be maximizing your visual scan guided by the relative height to you and also planning or implementing avoiding action. E.g. climbing or descending to increase separation.
“TRAFFIC DANGER”- The aircraft is now in relatively close proximity to you, (particularly if you have the detection range set to 'Ultra Short’ ) and all efforts should be concentrated on a visual scan to locate it, together with any and all appropriate action to maximize separation.
Using the above voice alerts in conjunction with the visual alerts from the RADAR or Electronic Flight Bag screen will allow you to use PilotAware for strategic situational awareness. In this manner, you will be aware of the aircraft at 10Km, 5Km and then at 3Kms and more importantly its height separation as it progresses towards you. Thus alerted you will have the best knowledge available on whether to climb or descend to increase vertical separation.
Please remember that because of the significantly higher output of CAT transponders, it's possible that you will not be able to visually see the contact for which you have received a voice alert because it will be too far away. If this is happening regularly, then reduce the sensitivity selected on the Configuration Page.
Note Mode-S/3D detected aircraft is treated as a target with a bearing so the voice alert that you get with a Mode-S/3D target will be the same as a target with a bearing as described earlier. This type of voice alert gives much more information.