Model	Track Selector	GPS Nav Mode	Altitude Hold	Trim Sensing Servo	Vertical Speed Select	GPS Steering	Nav Modes	Vertical GPS Steering	Altitude Select	Auto Pitch Trim	Yaw Damper
Altrak	-	-		-	-	-	-	-	-	-	-
Altrak VS	-	-				-	-	-	-	-	-
Digitrak			-	-	-	-	-	-	-	-	-
Pictoral Pilot			-	-	-	-	-	-	-	-	-
DigiFlight II				-	-	-	-	-	-	-	-
DigiFlight IIG		`		-	-		-	-	-	-	-
DigiFlight IIVS						-	-	-	-	optional	-
DigiFlight IIVSG							-	-	-	optional	-
DigiFlight IIVSGV							-		-	optional	-
RV-10 AP							-			optional	optional
AP100									-	optional	optional
Sorcerer										optional	optional

Servos, mounting brackets, and linkages for the desired system may be purchased and installed as required during the construction of a new aircraft. This partial purchase can be done with no penalty on the total system price. For most popular aircraft TruTrak has servo installations designed and include aircraft specific mounting brackets, and push-rods at no additional cost.

The standard TruTrak servos employ a digital stepping torque motor operating through a single gear pass to drive the output shaft. With no brushes to wear out, this is the most reliable mechanical servo available, one that should outlast the aircraft in which it is installed. To accommodate variations in aircraft requirements, TruTrak provides a choice of three different torque capability servos, which are mechanically interchangeable, and a high torque which is mechanically similar. The maximum torque capability of the servo is electronically set to the lowest value that allows the autopilot adequate control authority, so the human pilot can override the autopilot with the least possible effort

For simplicity and reliability the standard servo remains coupled to the control system when not active and does impose a small residual torque load. This is why the smallest servo with adequate torque capability should be chosen.

The high torque servo (HB) is a new design that allows the TruTrak autopilots to fly much larger aircraft than possible with the standard servos. For example, the Lancair IV Turbine, L-39, and Virgin Atlantic GlobalFlyer, are all flown using the high torque servo.