Mini Series EFIS

Mini Series EFIS

4.3″ Mini-X EFIS shown above.

The Mini is not a compromised instrument. It is a complete EFIS capable of synthetic vision, with a GPS navigator, incorporating the same technology that made GRT famous with its high-integrity AHRS. It is completely suitable as the primary instrument in your panel or as a backup for attitude, heading, track, airspeed, altitude and VSI. Highly readable airspeed/altimeter tapes and rotating drum-style digital display. Free database updates for all US territories. Jeppesen databases available worldwide. Simple installation – connect power, ground and mount the GPS antenna on your dash. Incorporates a full AHRS solution (internal) that does not require GPS or air data to provide attitude data.

Starting at only $1,395

4.3″ Mini-X EFIS

View pricing and options

As A Primary Flight Display

The Mini includes an electronic attitude source (AHRS) that is not dependent on GPS and/or air data. IFR certifiable altitude, vertical speed, and airspeed are boldly shown with tapes and smoothly rotating drum-style digital displays that instinctively convey value and trend. Internal or external GPS navigation and steering data is provided on the PFD, and the -X and -AP variations include highway-in-the sky guidance to any runway in the database. The addition of the external magnetometer adds heading and winds.

The primary flight display screen terrain showing relative height. In the upper left the autopilot/flight director mode is shown as synthetic approach to runway 35. The flight director is commanding a slight pitch down in the center of the screen. The airspeed and altimeter drums move smoothly and the high-contrast digits make them highly readable. Extending up from the runway is the way-point balloon.

A Full-Featured Moving Map

Based on the moving map in the Sport and HX, the moving map has the features you would only expect to find in a full EFIS. It includes such features as terrain relief, relative terrain height color coding, nearest functions, airport details including frequencies and runways, and much more. When connected to an external GPS, its flight plan and steering information can be displayed on and drive the map.

Smooth Rotation Moving Map

Hand-held or panel mount GPS navigators update their display once per second. Some EFIS based moving maps do same. The result is a jerky and delayed map. The Mini combines AHRS and GPS data to update its map at up to 15 times per second, resulting in a smoothly rotating map. Rolling out of a turn precisely on track becomes easy and the extended runway centerlines eliminate the guess work, making navigation easier and more precise.


When equipped with the moving map, the Mini-X and Mini-AP extends its role by coupling to other navigation sources, such as navigation radios. The Mini includes and OBS (radial) selector for VOR or LOC/ILS navigation. Lateral and vertical deviations are also displayed on the primary flight display.

Integrates With Other GRT Equipment

The Mini adds automatic cross-checking of its attitude with any GRT EFIS screen. The GRT EFIS flight plan is displayed and may be edited on the Mini. Baroset and dimming is shared. In short, it adds another screen to your GRT equipped panel with complete integration via the inter-display unit link.

Angle-of-Attack (AOA) Sensing/Stall Warning

Angle-of-attack sensing is available as an upgrade to all versions of the Mini-EFIS. Sensing is via a two-port 45 degree pitot tube, such as those commonly available from a variety of manufacturers, or using a probe fashioned by the builder. This method has no moving parts, and allows the use of heated pitot tubes that preserve the stall warning function even in the presence of icing.

The GRT Avionics AOA function drives on-screen AOA symbology that shows too fast/too slow/optimal approach speeds, as well as stall warning. In addition, an audio output is provided on the Mini-X/AP. This audio provides an approaching stall warning annunciation (a pulsating tone that varies with proximity to the stall warning angle) and a solid tone indicating stall is imminent.

Heads-Up Display Capable

A heads up display can now be part your your GRT Avionics equipped airplane for as little as $300. Our pursuit of heads up display technology has led to support for the Hudly automotive after-market heads up display. Graphics optimizations in the GRT remote app, combined with the impressive readability and value of the Hudly have resulted in the first practical heads up display for experimental and general aviation (certified) airplanes.

  • Aircraft mounted heads-up display
  • Sunlight Readable Color Symbology
  • Primary Flight Data
  • Flight Director and HSI Guidance
  • Lateral/Vertical Deviation for Approach
  • Stall warning and all other features of GRT Remote app

Using Another Brand EFIS?

All versions of the Mini bring high-integrity attitude and air data to your panel, plus backup navigation that adds comfort to any situation. The Mini-AP adds even more! When the Mini-AP autopilot is engaged and being commanded by another EFIS, you are effectively provided with automatic attitude cross-checking, while enjoying the accuracy and ride comfort which made the GRT autopilot famous.

We don’t compromise on quality and it is evident before even turning the Mini on. The faceplate and case are milled from aluminum billet, protecting the instrument from physical damage, and providing structural integrity to your panel. Robust ports for the pitot/static connections mean you won’t be chasing pitot/static leaks here.  The buttons and knobs, the parts that get the most physical use, are also examples that quality was and always will be the first priority. We have used a Grayhill rotary encoder for the knob input.  While they are more expensive,  they have performed flawlessly since we began using them, and we’re not willing to compromise with anything less.

Which Mini Do I Need?


Mini-X gives you a  synthetic view of your world, including terrain, obstacles, runways, and even a 3-D flight plan. The Mini-X is also compatible with the digital magnetometer (can be shared with the Adaptive AHRS), providing magnetic heading, wind speed and direction.

Features include:

  • Synthetic vision provides a natural way of detecting nearby terrain and obstacles and position relative to nearby runways
  • Highway-in-the-sky guidance to any runway in the database increases approach accuracy and helps safeguard against shallowing an approach, day or night
  • Adds basic autopilot capability (when coupled to GRT servos), including lateral coupling to the GPS flight plan and altitude hold
  • Heading and altitude bugs for reference and autopilot control
  • Flight Director – The flight director makes you the autopilot. It combines attitude control, altitude hold and navigation into one, simple-to-fly chevron command symbol. Increases accuracy and simplifies hand-flying IFR. A great safety enhancement for a VFR pilot that wanders into IFR
  • External Magnetometer Compatibility – adding heading, wind speed and direction. Allows full accuracy attitude data even when GPS is unavailable
  • Full flight planning screen that integrates with any GRT EFIS
  • G-Meter with peak recording
  • Flight Path Marker – shows your path relative to terrain, obstacles and runways
  • Optional Moving Map with ADS-B display ($250)


Planning on the Mini-X with the external magnetometer? Want full autopilot capability? Why not move up to the mini-AP? It includes everything the Mini-X includes as well as:

  • Full auto-pilot functionality; including lateral and vertical navigation coupling, coupling to the synthetic approach, climb and descent on airspeed or vertical speed, and more
  • HSI display of GPS and navigation radio data, allowing it to be a primary or backup navigation head for all Garmin navigation receivers
  • G430/530/650/750 interface capability via the optional ARINC 429 adapter
  • Includes full moving map with terrain colored to show its proximity to your altitude, flight planning, nearest airports, weather frequencies, and even allows you to tune your compatible radio. 
  • Includes external magnetometer. 

Engine Monitoring (Mini-X/AP only)

Practically identical to the engine monitoring provided by the HX and Sport SX, the Mini engine monitoring provides 6 engine pages, percent power calculation, and GRT exclusives (such as the EGT and CHT time histories and engine efficiency via the specific fuel consumption display).

Probably the most popular of the engine monitoring screens is the EGT time history page. In addition to two user-programmable dials, fuel management, and basic engine data. This screen includes a 2-minute history of all EGTs. This GRT exclusive allows you to effortlessly distinguish between engine problems affecting one cylinder or the engine itself. It also makes it easy to see small changes in engine operation that might not otherwise be noticeable. Even better, this display provides reassurance that your engine is running normally, especially when flying over water or at night. If the EGTs are steady, so is the engine.

Shown here, you can see some unusual fluctuations in the white EGT time history (cylinder 1). The rise in EGT 1 temperature near the center of the time history suggests a spark-plug might be intermittently fouling, causing the EGT to increase, and then return to normal. This subtle change in engine operation would probably not be felt, but becomes obvious thanks to this exclusive feature.
The traditional EGT/CHT bar graphs are provided by this screen. This page makes it easy to see how far your engine (especially the CHTs, which reflect engine cooling) are from their limits. The lack of time history makes this page less useful for detecting abnormal engine operation than the EGT time history screen.
CHTs are also displayed with a time history on this page. When managing engine operation to control CHTs (such as during the climb to cruising altitude), this display makes it easy to see if CHTs are still climbing. In this screenshot it is easy to see that the engine had been operating at low power, causing the CHTs to drop.
The Statistics page provides useful data, that like the EGT time history, you will find you can’t live without. The MPG page allows you to find the airspeed that optimizes fuel economy to account for altitude and winds. The specific fuel consumption (SFC) indicates the amount of fuel (in pounds) being burned to make one horsepower for one hour. This reflects engine efficiency. If this value increases (on a fixed-pitch prop) or changes up or down (constant-speed prop), you need to lean again. Without this GRT exclusive, there is no way to know if you need to lean again due to changing conditions.
Four user-programmable dials allow for easily-readable engine data. Excellent for piston and turbine engines. The dials allow user settings for color bands, bugs, scaling, resolution and much more!
Need more customizing? The Bar Graph page allows you to customize this page with bar graphs across the entire screen. That big black area is yours to customize.


Real-time traffic and weather is now a practical reality, and it is fully supported by the Mini. Unlike a tablet, the Mini’s screen is always readable, remains fully controllable in turbulence, and doesn’t suffer from overheating problems.

  • NexRad Weather Radar
  • METAR data, and terminal area forecasts available on details page
  • Airports color-coded based on METAR data
  • TFR (Temporary Flight Restrictions) graphically and with text descriptions
  • Real-Time Traffic (requires ADS-B Out to assure traffic is provided to your airplane)
NexRad weather radar showing the intensity of precipitation. This screenshot was taken with a range of 150 nmi, providing plenty of anticipation for approaching conditions. Note the top-of-climb is the location predicted by the green arc.
ADS-B weather on a 35-mile range. Note that weather is shown relative to airports and surrounding airspace.
Airports are color-coded to show VFR, marginal VFR, IFR and marginal IFR conditions. Wind barbs are also shown, depicting surface winds. (Actual screenshot from a demo recording by James Clark)
METAR and TAF data is provided in the text on the airport details for all airports providing weather. Provided in “Airport Details” this data is only two clicks away for your destination airport, and is easily selectable with the GRT exclusive “radar sweep” data selector.
Traffic is overlaid on the moving map, and also appears on the primary flight display. In this example, traffic is clearly visible 600’ above the airplane, tracking off the left side of the airplane. Alarms are generated if traffic poses a safety threat.
The Mini provides a conventional HSI display, driven by the navigation mode selected on the Mini. With the feature set, ADS-B traffic can be displayed on the HSI screen. In this example, it is being driven by GPS data, but will also show ILS and VOR data. ADS-B traffic of unknown altitude is shown with a ground track passing behind the airplane.

Control Radios and Flight Plans with Your Android Phone or Tablet…

Install an optional Bluetooth dongle and connect with your Android phone or tablet using our GRT REMOTE App for Android*. Fully control your connected radios, create & edit active flight plans, and view the flight instruments all on your Android tablet or phone–perfect for the backseat co-pilot. The radio tuning portion of the app offers so much information, you may not want to tune them without it!


Mini model comparison table

Features Mini-X Mini-AP
Airspeed Indicator
Attitude Indicator
Magnetic Heading With Remote Magnetometer Optional 
Turn Coordinator
Vertical Speed
Wind Vectors
Remote Transponder Controls
Serial Altitude Encoder
Serial Link to GRT EFIS
Sunlight Readable LED Display
Wide Viewing Angle
480 x 272 Hi-Res Screen
Data Logging
Autopilot Controls Limited*
Heading Bug
Altitude Bug
Flight Director Limited* 
ARINC 429 Interface   Optional
GPS CDI Needle
Highway In The Sky
Synthetic Vision
Stand-Alone GPS Navigator
Moving Map/ADS-B Display Optional 
Internal 5-Hz VFR WAAS GPS
Glareshield GPS Antenna
GPS Serial OUT
Input for External GPS
OAT (for TAS, Density Alt) Optional Optional
Internal Battery Backup Optional Optional
Voter for Dual AHRS
Engine Page (EIS required)
Bluetooth (dongle required)
Base Price $1,395 $2,100
Optional Remote Magnetometer $260 Included
Optional Moving Map/ADS-B Display $250 Included
Optional OAT probe $94 $94
Optional Internal Li-Ion Battery $180 $180
Optional ARINC 429 N/A $450
Standard GRT Roll Servo $770 $770
Standard GRT Pitch Servo $770 $770
High-Airspeed Air Data Option For Above 335 MPH IAS $0

Must be specified at time of order   

Optional Angle-of-Attack (Direct Sensing via Dual Port Pitot Probe) $450 $450


  • OAT, TAS and Density Altitude are displayed when the Mini is connected to a GRT EFIS or with the optional OAT sensor.
  • Li-Ion battery for Mini-AP does not power the servos (Servos require a significant amount of power).
  • Autopilot controls for Mini-X do not include vertical guidance for IFR approaches. This feature is included with Mini-AP when equipped with ARINC 429 wired to a suitable IFR GPS navigation unit.
  • Control of the Trig TT22 remote transponder is supported.
  • For pricing and information on high torque servos, servo wiring harnesses and mounting kits, see our product guide.



Pricing and Options Additional Screenshots Documentation Printable full size planning card