HomePro PilotEZ PilotAltitude ControlFrequent QuestionsLiteratureSales AssociatesContact


Precise Navigation

Because the EZ Pilot uses GPS signals as its reference, it is capable of tracking the flight plan that you have entered into your GPS receiver very accurately.  Typically, in smooth air, you will see cross track errors (XTK) of less than .02 miles (about 100 feet).  This is significantly better than what was possible with older analog autopilots. With the EZ Pilot, you will often observe tracking between 0.00 and 0.01 miles of cross track error (between 0 and 50 feet).  Turbulence can obviously have an adverse effect on this accuracy, but it will still track closely to the course centerline.  Top

Solid State Gyro

(Click to enlarge)
Mechanical gyros have been a mainstay in aircraft instruments for years.  However, they are now being strongly challenged by some very impressive solid state electronic gyros that are small enough to fit into a 1/4 inch cube.  These gyros are highly responsive, accurate and not subject to the effects of mechanical wear and breakage of their mechanical ancestors.  The new gyros are also different in that they do not obtain their attitude reference from gravity, but derive it from electronic signals from GPS receivers, electronic magnetic sensors or accelerometers.  The EZ Pilot utilizes these new gyros to provide fast, accurate and reliable rate information. Top

Microprocessor Controlled

The microprocessor in the EZ Pilot is a powerful computer that executes millions of instructions each second.  It analyzes information it receives from the gyro(s), GPS receiver and the pilot, and issues instructions to the servo to control the ailerons of the aircraft.  The processor computes course error corrections, closure rates and appropriate intercept angles.  It also monitors temperature changes to maintain gyro stability and provides the data that appears on the faceplate display.  Because the microprocessor uses "flash" memory to contain its programming it can be updated when improvements or new features are available.  Top

Digital Precision

The information that an autopilot receives from your GPS receiver is in a digital format that is specific and precise.  The VOR and heading references commonly used by other autopilots are analog (a varying DC voltage) and are somewhat ambiguous about precise values so these autopilots work by trying to null the voltage to keep the needle centered and the aircraft on the course centerline.  GPS provides digital bearing and tracking information that are not only accurate but precise in value.  To utilize GPS, the older autopilots must convert the digital information into an analog voltage to drive the autopilot.  The EZ Pilot does not require this step because the microprocessor directly interprets the digital values for aircraft guidance control. Top

Accurately Tracks GPS Flight Plan

Flying the EZ Pilot is as simple as entering a flight plan into your GPS receiver and pressing the "Servo" button.  The autopilot does the rest.  Using GPS signals from your receiver, the autopilot will typically track within .02 nm of course centerline in smooth air.  This exceeds the capabilities of many "certified" autopilots when tracking a GPS flight plan.  Top

Adjustable Course Tracking

Pressing the "Mode" button will sequence the autopilot from the track (TRK) mode to the course (CRS) mode.  In the CRS mode the pilot selects a desired course using the L - R (left - right) switch and the autopilot will fly that course, using the GPS data to assure an accurate course over the ground.  Desired course can be set to within 1 degree.  Top

Unique "Intercept" mode

A unique feature offered by the EZ Pilot autopilot is it's ability to intercept a preprogrammed flight path.  For instance, if you have disengaged the autopilot to manually fly the aircraft away from the courseline (perhaps at the request of ATC) you may simply push the MODE button to enter the Intercept (INT) mode, and then engage the servo.  The aircraft will turn to a preprogrammed intercept angle (25 degrees is the default) and fly toward the courseline.  When the aircraft reaches approximately .5 miles from the centerline (distance varies with aircraft speed), the autopilot will automatically switch to the Track (TRK) mode and turn smoothly onto the courseline.  Top

Remote Auxiliary Servo Disconnect

When flying with the autopilot engaged the pilot may disengage the servo by momentarily pressing a remote "servo disconnect" switch located on the control stick or control wheel.  This will free the controls for manually flying the aircraft.  The "Servo" button on the instrument faceplate will also disengage the servo when pressed.. Top

Selectable GPS Data Display

All bearing-to-waypoint and track information is constantly displayed for pilot reference.  A convenient "Display" button on the instrument faceplate also allows the pilot to sequentially review a turn coordinator, distance to waypoint, estimated time to waypoint, waypoint identifier, crosstrack error, groundspeed and Track Offset Position (TOP) on the bottom right-hand portion of the display.  Top

Works with Portable or Panel Mount GPS

You might assume that all GPS receivers provide identical data stream outputs.  This is unfortunately not the case.  Most panel mount GPS receivers provide a data stream output often referred to as an AVLINK data output and most handheld GPS receivers output a data stream that conforms to the NMEA 0183 standard.  Even with these two standards as reference many GPS receivers do not conform exactly to the specifications, but alter the data stream for various reasons.  The EZ Pilot microprocessor analyzes the data stream to determine if it is an AVLINK or NMEA format, and then configures the autopilot to accept the data.  It also has special code to recognize a number of receivers that do not adhere strictly to the standards, and it will further adjust the autopilot to accept those it recognizes.  A list of the currently acceptable receivers may be obtained by contacting the factory using the "Contact" section of this web site. 

Bright OLED or Backlit LCD Display

Trying to read the LCD (liquid crystal display) screen on most handheld and many panel mounted GPS receivers can be difficult in poor lighting conditions.  The EZ Pilot overcomes this difficulty by providing a bright Organic Light Emitting Diode OLED) display to present information to the pilot.  In aircraft that experience a lot of direct sunlight on their instrument panels, an LCD option (backlit for night operation) is also available.    Top

Control Head Weighs Less than 8 ounces and Servo Weighs only 24 ounces

Because the weight of the MEMS gyro is just a few grams, the total weight of the autopilot control head is greatly reduced.  Top

Pilot Command Steering

In either the TRK or CRS mode, if the remote servo disconnect switch is held down for more than 3 seconds, the servo LED will begin to flash, indicating that the PCS mode is active.  While holding the button down the pilot may manually fly to any new course desired and, upon releasing the switch, the autopilot will enter the CRS mode and track the new course over the ground.  Top

Selectable Track Offset Position (TOP)

While flight testing the autopilot and flying flight plans using published airways, we often encountered other airplanes using the same airway.  While this was usually during climb or descent (for either us or the opposing aircraft) it was a potential safety issue.  As more aircraft are using precision GPS receivers to navigate, and many are coupled to autopilots, such close encounters are likely to increase.  For this reason, the EZ Pilot incorporates a Track Offset Position (TOP) feature that allows the pilot to select a track offset of up to 1 mile.  This places the aircraft away from the course centerline where much of the traffic might be found.  It is interesting to note, that if all aircraft positioned themselves to the right of the published course centerline (for instance), opposing traffic would always be on the opposite side of the centerline.  Top

Speed Controlled Bank Angle

A “standard rate turn” of 3 degrees per second may result in a comfortable bank angle at 130 knots, but as speed increases the bank angle must be increased to achieve the standard rate of turn.  In faster aircraft this steeper bank may be uncomfortable to some pilots and, indeed, may exceed the capability of an altitude hold system to maintain altitude properly in the turn.  To remedy this, the EZ Pilot has a means whereby the users can adjust the maximum rate of turn to their personal satisfaction.   When shipped, the EZ Pilot is defaulted to an “automatic” mode where the actual turn rate is automatically adjusted based on groundspeed (as measured by your GPS).  For aircraft cruising at groundspeeds of 140 knots or greater the automatic mode will decrease the allowable turn rate to keep the aircraft bank angle at a comfortable maximum of approximately 15 degrees.  Slower speeds will allow a standard rate turn of 3 degrees per second.  Top

Adjustable Turn Rate Limit

If your cruise groundspeed is typically less than 150 knots, or if you do not mind the higher bank angles at the higher groundspeeds, you may want to select the MANUAL mode.  In the MANUAL mode you can set the maximum turn rate to a fixed limit.  It is adjustable from 1 degree/sec to as high as 3 degree/sec, in increments of 1/10th degree/sec.  Top

Emergency Course Reversal

In an effort to increase safety and save lives, this mode may be implemented as an emergency aid to the VFR pilot who inadvertently enters IMC conditions and needs to execute an immediate course reversal.  It is important to realize that the autopilot must be turned on and receiving a good GPS data signal for proper operation.  You may be tracking a flight plan but a sudden IMC encounter may not leave you with an opportunity to reprogram your GPS to invert the flight plan.  This procedure does not require you to adjust your GPS receiver.  If you are manually flying your aircraft, this procedure will also work because the servo does not have to be engaged to initiate this emergency procedure.

 The procedure is simple and straightforward.  Press and hold the MODE button for three seconds.  That’s all you need to do  After three seconds the following will occur:
    1         The servo will be energized (if off) and the wing leveler function will engage.
    2         The upper right display line will read “TRN 180”
    3         The lower right display line will be forced to the turn coordinator display
    4.   A 175 degree right course reversal will be executed

After reversing course, the pilot may alter the direction of flight using the L - R switch or engaging the PCS mode. 

Automatic Trim Compensation

The EZ Pilot will automatically compensate for trim imbalance caused by fuel burn, moderate inaccurate trim settings, and the like.  Top

Automatic Servo Disconnect on Takeoff

As a safety feature, during takeoff roll, the EZ Pilot checks the status of the servo.  If the servo has inadvertently been turned on prior to takeoff, at 25 knots GPS groundspeed it will automatically disconnect the servo, allowing free movement of the ailerons.  This is a backup feature only and should not be relied upon to replace a necessary preflight checklist item.  This feature relies on a proper GPS signal being received and will not function properly if the GPS is not active and providing data to the autopilot. 

Excellent Turbulence Performance

The MEMS gyro that is employed in the EZ Pilot autopilot is very responsive to even the slightest movement.  Because the gyro is mounted so that it can sense  roll moment as well as yaw, it immediately responds to any un-commanded roll movements caused by turbulence.  The inherent high sensitivity and fast response of the system results in excellent turbulence penetration.  Top

Fully Configurable Data Windows

Most autopilots, even very expensive ones, are content to simply track a course.  The EZ Pilot aspires to a higher calling.  Two data "windows", the upper and lower right-hand display quadrants, can be used to present information present on the GPS data stream.  Both can be configured to present any of the items listed in the "Selectable GPS Data Display" feature, above.  However, the upper right-hand display position may also be used to present user-selected, GPS derived data.  Many EZ Pilot users find that they don't look at their GPS receiver much after the flight plan has been entered.  It's easier to read the information from the EZ Pilot display.  Top

GPS Data Scan Function

If the DISPLAY button is momentarily pressed two times in quick succession (double-clicked) the variable field on the bottom right-hand side of the display will enter or exit the “Scan Mode”.  In this mode the waypoint designator, RNG, GS, XTK, TOP and ETE(e) fields are sequenced in the display at a 1.2 second rate.  This can be useful for sequentially monitoring all the parameters put out by the GPS without having to manually select each parameter.  Top

Compatible with Existing Navaid Servos

For many years a large number of experimental homebuilt planes have flown successfully and reliably using a Navaid autopilot.  The EZ Pilot provides a servo output that is compatible with the Navaid servo, so those who have a properly operating Navaid servo installed can use it with the EZ Pilot control head, thus saving a considerable amount of money.  A short jumper cable can be provided with the control head that will plug into the existing servo control harness.  Top