Dynon Avionics SkyView Autopilot In-Flight Tuning Guide

SkyView

Autopilot In-Flight Tuning Guide

This product is not approved for installation in type certificated aircraft

Document 102064-000, Revision B

For use with firmware version 10.0

March, 2014

Permission to print this this manual is granted to third parties

Table of Contents

Revision

Revision Date

Description

June 2013

Initial release

March 2014

Updated for SkyView v10.0:

- Added BANK ANGLE LIMIT

- Mention of SV-AP-PANEL only active in EXPERT mode

2008-2014 Dynon Avionics, Inc. All rights reserved. No part of this manual may be reproduced, copied, transmitted, disseminated or stor ed in any storage medium, for any purpose without the express written permission of Dynon Avionics. Dynon Avionics hereby grants permission to download a single copy of this manual and of any revision to this manual onto a hard drive or other electronic storage mediu m to be viewed for personal use, provided that such electronic or printed copy of this manual or revision must contain the complete text of this copyright notice and provided further that any unauthorized commercial distribution of this manual or any revision hereto is strictly prohibited.

Information in this document is subject to change without notice. Dynon Avionics reserves the right to change or improve its products and to make changes in the content without obligation to notify any person or organization of such changes. Visit the Dynon Avionics website (www.dynonavionics.com) for current updates and supplemental information concerning the use and operation of this and other Dynon Avionics products.

Revision History

Table 1–SkyView Autopilot In-Flight Tuning Guide Revision History

Table of Contents

Copyright ....................................................................................................................................................................... ii

Revision History ............................................................................................................................................................. ii

1. Overview 1-1

Purpose ....................................................................................................................................................................... 1-1

Things to Look For ...................................................................................................................................................... 1-2

Resetting Autopilot Defaults ...................................................................................................................................... 1-2

2. Flight Test Preparation 2-1

Overview ..................................................................................................................................................................... 2-1

Disconnecting the Autopilot ....................................................................................................................................... 2-1

Accessing Autopilot Setup .......................................................................................................................................... 2-1

3. Roll Axis – TRK and Turns Procedure 3-1

Overview ..................................................................................................................................................................... 3-1

Flowchart .................................................................................................................................................................... 3-2

BANK ANGLE LIMIT ..................................................................................................................................................... 3-3

4. Pitch Axis – IAS Hold Procedure 4-1

Overview ..................................................................................................................................................................... 4-1

Flowchart .................................................................................................................................................................... 4-2

5. Pitch Axis – Altitude Hold and Capture Procedure 5-1

Overview ..................................................................................................................................................................... 5-1

Flowchart .................................................................................................................................................................... 5-2

6. Turbulence Tuning Procedure 6-1

Overview ..................................................................................................................................................................... 6-1

Flowchart .................................................................................................................................................................... 6-2

SkyView Autopilot In-Flight Tuning Guide - Revision B ii

Table of Contents

7. Roll Troubleshooting 7-1

Roll Troubleshooting Procedure ................................................................................................................................. 7-1

Roll Performance Troubleshooting Procedure ........................................................................................................... 7-2

Appendix A: Autopilot Settings –Defaults 8-1

SkyView Installation Guide iii It is critical that once tuned, you familiarize yourself with AP procedures, and verify the performance of the autopilot on approaches in VMC before use in IMC.

Performance of the AP is degraded by excessive servo slippage. If during verification of approach performance you find that the servo is slipping, verify that you have the torque set to the maximum value, and if slips continue, contact Dynon for advice on servo sizing.

HDG mode performance is only as good as your compass calibration. If you have concerns about your compass, refer to the compass calibration guide in the SkyView System Installation Guide.

The SV-AP-PANEL is enabled when AP CONTROLS are set to EXPERT mode. For tuning procedures performed in SIMPLIFIED mode, the buttons on the SV-AP-PANEL will not be active.

1. Overview

Purpose

The goal of the AP tuning procedure is to maximize the performance of the Autopilot in your

aircraft. The steps described accomplish this systematically and reduce guesswork, so follow

them carefully.

All procedures in this guide should be exercised regardless of how the autopilot is intended to

be used in the aircraft. In particular, if you are using the vertical navigation features of the

autopilot, pay special attention to the IAS Hold tuning procedure. Tuning this well will give the

best results when using vertical guidance.

Once IAS hold is well tuned, the AP will be able to get the best performance during normal

climbs and descents in either expert or simplified modes, and the altitude capture and hold

procedure should be used to finalize vertical performance.

Once you have configured the autopilot to capture and hold airspeeds and altitudes, you may

wish to adjust the ride quality in turbulence, particularly on the glideslope.

Similarly, the Roll Axis TRK and Turns Procedure will ensure best performance both in normal

turns and when following lateral guidance on approaches.

SkyView Autopilot In-Flight Tuning Guide - Revision B 1-1

Overview

Things to Look For

Most autopilot problems come down to two things: SLIP and SLOP. Be alert for the SLIP

/ indication on either axis. While either SLIP indications are being displayed NOBODY IS FLYING THE AIRPLANE. Resolve SLIP issues on either axis before proceeding, either by increasing torque, switching to a larger servo, or contacting Dynon for service.

Lost motion (SLOP) between the servo and the control surface will have a negative impact on performance. Verify that the control surface cannot move more than one degree (total motion) while the servo is holding position.

The Flight Director provides a valuable tool for evaluating the performance of the AP. If the autopilot is not able to keep up with Flight Director command bars, sensitivity should be increased. If the autopilot can keep up, but gets a late start and lags behind the flight director, PITCH GAIN or ROLL GAIN can be used to speed up response. Use sparingly! Excessive PITCH GAIN and ROLL GAIN can result in rough performance.

Resetting Autopilot Defaults

A final note on tuning the autopilot: Less is more. Before changing any settings, try each procedure and determine if performance is acceptable as-is; often you will have to make only

minor changes. If you find that you’ve turned all the settings all the way up, you’ve probably

gone too far. Stop and review the procedures, and then go back to the defaults and re-evaluate performance.

If you feel you need to reset the settings in the Autopilot Settings menu back to their defaults, see Appendix A: Autopilot Settings –Defaults for the default values.

1-2 SkyView Autopilot In-Flight Tuning Guide - Revision B

It is highly recommended that you bring someone along on the first autopilot test flight. At many points, the pilot’s attention will be divided between documentation, configuring SkyView, and maintaining situational awareness.

2. Flight Test Preparation

Overview

The flight test should be conducted on a clear, VFR day. Before commencing the flight test, ensure that you have adequate altitude, clear weather, no traffic, no obstructions in the flight path, great visibility, no airspace conflicts, etc. It is recommended that clearing turns be performed before executing each procedure.

Disconnecting the Autopilot

If autopilot behavior, performance, or interference with the controls is cause for concern while flying, remember that the autopilot can be disconnected the following ways:

 Press the Autopilot servo Disconnect button  Within the Simplified AP Controls: Press the OFF button  Within the Expert AP Controls: Press the AP button  On the SV-AP-PANEL Autopilot Control Panel, push the AP button

(if SV-AP-PANEL is enabled – AUTOPILOT CONTROL set to EXPERT)

 Pull the autopilot circuit breaker or remove the autopilot fuse

Accessing Autopilot Setup

In the following instructions, the setup menus for Autopilot tuning are accessed by

Pushing Buttons 7+8

Then, select AUTOPILOT SETUP (and click the knob to the right, once). You will then be in AUTOPILOT SETUP.

SkyView Autopilot In-Flight Tuning Guide - Revision B 2-1

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