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Updated LPV STC for Garmin GNS units

Gama Aviation’s Part 23 EASA AML STC has received an updated approval today.
The amendment allows LPV certification of existing GNS installations without the need to install a dedicated set of annunciators, subject only to the position of the GNS being within a prescribed distance of the vertical centreline of the primary attitude indicator. This harmonises the requirements with the existing FAA GNS-W STC and the similar GTN-series STC. The Gama STC includes updating a non-WAAS unit to a GNS-W.

For anyone interested, Gama will be making a presentation on the STC at Aero Friedrichshafen on April 21st at 14.00 in the Vienna room in conjunction with the European GSA and PPL-IR.

Avionics geek.
Somewhere remote in Devon, UK.

To add a bit of clarification to my last post about required annunciation with a GNS-W for LPV approval:

The required annunciation is as follows:

GPS or Nav source to CDI/HSI.
GPS Loss of Integrity (INTEG or LOI)
GPS in Approach mode
GPS in Terminal mode (TERM)
GPS Message (MSG) and GPS Waypoint (WPT)

Where the GNS-W unit is installed within the ‘Normal’ or ‘Primary Maximum’ field of view (as defined in FAA AC23-1311-1C section 15), then the additional annunciators are not required as you can rely on those shown on the GNS unit. To be more specfiic on the field of view, for a typical aircraft flown P1 from the left-seat, then the GNS left edge must be no more than 13.8" to the right of the vertical centre-line through the attitude indicator. For an aircraft flown from the right (SF260 etc), then the right edge of the GNS-W must be no more than 11.8" to the left of the attitude indicator vertical centre-line.

For left seat aircraft with a radio stack further to the right such as early Beech F33 Bonanza or older B55/58 Barons with the centre-mounted control column, these will almost certainly require external annunciation.

Hope that helps.

Avionics geek.
Somewhere remote in Devon, UK.

Gama Aviation are considering a further update to the EASA AML STC for GNS-W LPV approval which will add some additional compatible autopilots and include some EASA orphaned aircraft for which we’ve received particular enquiries. Does anyone on the forum have any orphaned types which they’d like to see included?
We will also be trying to remove the requirement for a second Com provided that a back up Nav is available. This will harmonise the STC with the requirements in Garmin’s GTN650/750 STC for aircraft below 6000 lbs.
Any comments greatly appreciated.

Avionics geek.
Somewhere remote in Devon, UK.

Good job!


A further update to our GNS-W LPV STC has just been approved by EASA.

We now have all bar one of the EASA Orphaned aircraft included on the AML. We have updated the autopilot list to include the DFC90, Century IV and a couple of others and added some additional compatible Nav indicators. We’ve also managed to remove the requirement for a second Comm for non-commercial aircraft (so we match the newer Part NCO requirements). A second Nav is still required but an ADF is not an automatic requirement – it’s given as a note in the AFMS to make the pilot aware that one may be required if a published GPS approach specifies the use of an NDB.

Avionics geek.
Somewhere remote in Devon, UK.
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