Copyright © 2016  Grand Rapids Technologies, Inc.

Electronic Flight Instrumentation for Experimental Aircraft Since 1991

A Fully Featured Stand-Alone Autopilot Meets a Top Notch EFIS in a Beautiful Package. We are now shipping our new MINI-AP, the backup EFIS that can do much more than just keep you upright in an emergency.

We designed the Mini-AP with three main goals in mind:

As an IFR backup flight instrument, the Mini-AP can do what no other brand of backup display can do for GRT Horizon and Sport users:



Mini AP

Remote Magnetometer and Battery Options shown

Remote Magnetometer

Get magnetic heading with the remote magnetometer-standard with the Mini-AP. The remote magnetometer enables the Mini to show gyro-stabilized magnetic heading. In other words its a self-correcting directional gyro-no user assistance required!

With the standard remote magnetometer, the Mini-AP will gain several additional features. It also will give you your Wind Vector and Flight Path Marker.

The Wind Vector conveniently displays how the wind will affect the aircraft at a glance. It breaks the wind into two components: a headwind/tailwind component and a cross wind component. The headwind or tailwind component will add or subtract to your true airspeed.  The cross wind component shows at a glance the deviation that the winds will cause from your heading and helps with the correction needed to compensate for the deviation. The wind vector can also display the wind magnitude and direction. This can be compared to reported winds aloft to help find a more favorable wind speed and direction for your flight.


The Flight Path Marker shows you the direction that the aircraft is actually traveling on the primary flight display. Simply point the flight path marker to a way-point, runway, or in another direction that you would like to go and the airplane will go directly towards it. The marker is helpful when flying with a crosswind to determining the direction that you should fly in order to travel in the correct direction.

Moving Map

Make navigation a snap using the fully-featured moving map with the aircraft geo-referenced. The Mini will display the most important labels and landmarks needed to help a pilot get to their destination.

OAT Probe Option

Enable the Mini to automatically calculate true airspeed, density altitude and display outside air temperature with the OAT Probe Option. The OAT information also improves the wind vector and flight path marker information by eliminating the need to estimate the true airspeed.

Internal Battery Backup Option

Don't get left in the dark if the main power goes out. The Mini's optional built-in battery and charger combo option with user replaceable battery will power the Mini and remote magnetometer for a long time. It will last about 2 hours at full screen brightness, or 3 hours at a reduced brightness of 7 or less.  The Lithium Ion battery features redundant battery protection circuits and conservative operation, making it safer than other similar products on the market.

Autopilot Servos Option

Just add servos to add full horizontal steering autopilot with altitude hold. Enabling  the GRT autopilot helps reduce pilot workload and allows more focus on the task at hand. When on a longer cross country flight, the autopilot can help make the experience smoother and more relaxing. The high quality AHRS in the Mini drives the autopilot in a no-compromise manner. When you want the full experience of your aircraft, simply disable the autopilot with a simple press of a button and fly away.

ARINC 429 Option

Send and receive vertical steering commands and IFR navigation with the ARINC 429 option. Use the ARINC 429 in order to receive ILS/VOR from select IFR GPS and navigation radios. Send vertical steering commands to a 3rd party Autopilot system such as Trutrak.

Terrain Alerts

Watch out! Those mountain tops are getting close.

Synthetic Vision and Terrain Alerts on the Mini-AP will show flight path issues a full 10 miles away. An early warning will give time to either climb or find another route.

Simply flip over to the Moving Map page to find a way out. With the Terrain Alert overlay on the Moving Map, finding a way out is much easier.

Terrain 500-1,000 feet below the aircraft will be shaded yellow. Terrain within 500 feet below the aircraft will be shaded red.

Mini-AP Snapshot