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 Copyright © 2009-2014 by Dynon Avionics, Inc.
Table of Contents Copyright 2008-2014 Dynon Avionics, Inc. All rights reserved. No part of this manual may be reproduced, copied, transmitted, disseminated or stored in any storage medium, for any purpose without the express written permission of Dynon Avionics.
Table of Contents 7. Roll Troubleshooting 7-1 Roll Troubleshooting Procedure .................................................................................................................................7-1 Roll Performance Troubleshooting Procedure ...........................................................................................................
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.
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.
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. It is highly recommended that you bring someone along on the first autopilot test flight.
3. Roll Axis – TRK and Turns Procedure Overview This procedure tunes the roll autopilot servo and thus, the flight characteristics of the aircraft in heading holds and turns. This procedure should be performed with the autopilot roll axis in track (TRK+ALT) mode, where the purpose of the autopilot is to keep the aircraft’s GPS ground track aligned with the track bug (as well as hold altitude).
Roll Axis – TRK and Turns Procedure Flowchart Figure 1 – Roll Axis – TRK and Turns Procedure 3-2 SkyView Autopilot In-Flight Tuning Guide - Revision B
BANK ANGLE LIMIT After Roll Axis tuning is complete, BANK ANGLE LIMIT should be set to a value that results in a bank angle in AP that is comfortable for your plane and your preferences. A place to start is to set BANK ANGLE LIMIT to a value that yields a standard rate turn at typical cruise speed. The default BANK ANGLE LIMIT is 30°. The SkyView AP will always obey BANK ANGLE LIMIT. However, if BANK ANGLE LIMIT is set too low (such as 5°), the SkyView AP will be unable to turn.
4. Pitch Axis – IAS Hold Procedure Overview The goal of tuning IAS Hold is to give the AP the best possible pitch axis performance. Crisp speed control is a prerequisite for good altitude and glideslope control. Although IAS hold is only available in EXPERT mode, tuning will benefit SIMPLIFIED mode greatly, so even if you don't intend to use EXPERT mode, this procedure is essential for good performance.
Pitch Axis – IAS Hold Procedure Flowchart Figure 2 – Pitch Axis – IAS Hold Procedure 4-2 SkyView Autopilot In-Flight Tuning Guide - Revision B
5. Pitch Axis – Altitude Hold and Capture Procedure Overview Both holding and capturing altitude are related but distinct parts of the autopilot. The Altitude Hold Procedure which follows will address common problems, and once those are resolved, direct you to the Altitude Capture Procedure, which will tune your system to capture and hold vertical speed and capture altitude targets without overshoot. You must complete the IAS HOLD tuning procedure before performing this procedure.
Pitch Axis – Altitude Hold and Capture Procedure Flowchart Figure 3 – Pitch Axis – Altitude Hold Procedure 5-2 SkyView Autopilot In-Flight Tuning Guide - Revision B
Pitch Axis – Altitude Hold and Capture Procedure Figure 4 – Altitude Capture Procedure (Part 1 of 2) SkyView Installation Guide 5-3
Pitch Axis – Altitude Hold and Capture Procedure Figure 5 – Altitude Capture Procedure (Part 2 of 2) 5-4 SkyView Autopilot In-Flight Tuning Guide - Revision B
6. Turbulence Tuning Procedure Overview Once you have configured your autopilot to capture and hold airspeeds and altitudes, you may wish to adjust the ride quality in turbulence, particularly on the glideslope. In general, the autopilot will attempt to maintain a constant G-loading through bumps by pulling or pushing G to oppose G generated by "air pockets". The amount of G the autopilot will apply is limited by G ERROR LIMIT. If, for example, you encounter a 0.5 G updraft, and G ERROR LIMIT is set to 0.
Turbulence Tuning Procedure Flowchart Figure 6 – Turbulence Tuning Procedure 6-2 SkyView Autopilot In-Flight Tuning Guide - Revision B
7.
Roll Troubleshooting Roll Performance Troubleshooting Procedure Figure 8 – Roll Axis – Roll Performance Troubleshooting Procedure 7-2 SkyView Autopilot In-Flight Tuning Guide - Revision B
Appendix A: Autopilot Settings –Defaults ROLL Axis Setting Minimum Maximum Default 10% 100% 100% SENSITIVITY 1 24 10 ROLL GAIN 0.0 5.0 0.0 5 45 30 Minimum Maximum Default 10% 100% 100% SENSITIVITY 1 24 10 PITCH GAIN 0.1 3.0 2.0 ALTITUDE GAIN 0.1 2.5 0.6 PULL RATE 1.0 2.0 1.0 VSI GAIN 0.10 2.50 0.6 G ERROR GAIN 0.0 4.0 1.0 G ERROR LIMIT 0.10 1.00 0.
