Pilot's Guide to Avionics 2013-2014 - 57

pilot models are approved for the airplane, which requires
checking STCs and looking at caveats,” Wilken said. “In
some cases, even for approved model numbers, specific serial number ranges may require airframe modifications. Also,
check for outstanding items like service bulletins that may
have to be dealt with before making a quote. From the autopilot side of things, you will probably remove existing wiring
and brackets in an upgrade. Using old parts is just asking for
trouble. You may wind up with exactly the same problems
that led the customer to ask for an upgrade.”
Weber agreed that electrical system issues can be a
problem.
“We’ve got a Cherokee in here right now, and someone
installed a strobe in the belly where the servo needs to
go, so we’ve got to take care of that first,” Weber said. “A
lot of older airplanes have modifications that can cause
problems. Frequently, when we do a retrofit, we sell the
owner on removing abandoned equipment and old wiring.
We have to open the airplane completely to do the installation anyway. That eliminates the risk of shorts, simplifies
troubleshooting later, and the owner gets additional useful
load.”
Avidyne’s Aaron Hall added that his company’s DFC-90,
designed to replace other autopilots, has some special requirements that need to be addressed during initial inspection.
“A digital system like ours won’t tolerate systems being out of limit,” Hall said. “Look at the rigging of the flight
controls. We recommend a flight test, and roll and pitch
trim adjustment tests before attempting an autopilot installation. Look at the overall integrity of the existing system. If
the capstans are worn and dirty, they’ll need to be cleaned,
or in some cases, replaced. We recommend a rag test for
abrasions.”
Evans agreed that control rigging is a particular issue
of concern.
“Autopilots connect to flight controls via cable,” Evans
said. “Main cable tensions (aileron, elevator and rudder)
all have to be set correctly per the aircraft maintenance
manual. You need to understand the proper way to do this
per the manual. Most airplanes will require rig pins and removing counterweights to set correct tension. If you don’t
do that, and connect a servo to a cable that’s either too
tight or too loose, you’ll have problems. Bridle cables must
be set correctly with the right number of turns; there’s no
leeway. Attachment between the bridle and main cables
must be correct, and motion must be checked stop to stop;
otherwise, you have a potentially dangerous flight-control
- 57 -

“I worry that people with a little bit
of knowledge can get into a lot of
trouble. You need to really understand
the complete system before you start
making changes. Autopilots are highly
integrated with the airplane.”
– Bob Weber of Mayday Avionics

problem. Take the time, get it inspected correctly so you
can’t get a problem in flight.”
“Make sure the rigging is done in a way that won’t bind
with any surfaces, limit switches set correctly or clutch tension set correctly,” Hall added. “Doing those first will make
it much easier to complete the installation. Some airplanes
have wiring more than 20 years old. Inspect it; make sure
everything is correct, good continuity. If necessary, install
new wiring. In some cases, you may find the wrong wire
gauge was used in older installs; old analog autopilot could
tolerate that, digitals aren’t so forgiving.”
Evans recommended a complete ground check after
installation.
“Years ago, I had an experience with a servo that ran backwards,” Evans said. “Manual elevator trim worked correctly,
but the automatic elevator trim was reversed. In flight, it commanded full down trim. The clutch held it until it disconnected,
and then everyone’s head hit the ceiling. That should have
been checked before flight. You really want to make sure the
system is doing what it’s supposed to do.”
A flight test is required after installation, and Evans
noted, “An IFR day is not a good day to do an autopilot flight check. You do not want to start by engaging the
autopilot when the gear comes up. You want to be away
from traffic, in level flight, and with enough altitude to recover if something goes wrong. Then, check one thing at a
time – roll control each way, disconnect and make sure the
airplane is still properly trimmed, climbs, descents, NAV
tracking, capture altitudes above and below. In each case,
Continued on following page…



Table of Contents for the Digital Edition of Pilot's Guide to Avionics 2013-2014

From the Publisher
Interested in AEA Membership?
AEA Staff/Board of Directors
New Avionics Products for 2013
What's Up With Backup Instruments?
Going Glass
Before & After
Aircraft as Antenna Farm
Cockpit Innovations
Understanding Autopilot Upgrades
ADS-B Circa 2013
Portable Powerhouses, GPS and VHF
Minimal Panels
NextGen Status Report
Repair Stations
Manufacturers/Distributors
Affiliates/Index
AEA Member Company Index
Advertiser Index
Pilot's Guide to Avionics 2013-2014 - Intro
Pilot's Guide to Avionics 2013-2014 - Cover1
Pilot's Guide to Avionics 2013-2014 - Cover2
Pilot's Guide to Avionics 2013-2014 - 1
Pilot's Guide to Avionics 2013-2014 - 2
Pilot's Guide to Avionics 2013-2014 - 3
Pilot's Guide to Avionics 2013-2014 - Interested in AEA Membership?
Pilot's Guide to Avionics 2013-2014 - 5
Pilot's Guide to Avionics 2013-2014 - AEA Staff/Board of Directors
Pilot's Guide to Avionics 2013-2014 - 7
Pilot's Guide to Avionics 2013-2014 - New Avionics Products for 2013
Pilot's Guide to Avionics 2013-2014 - 9
Pilot's Guide to Avionics 2013-2014 - 10
Pilot's Guide to Avionics 2013-2014 - 11
Pilot's Guide to Avionics 2013-2014 - 12
Pilot's Guide to Avionics 2013-2014 - 13
Pilot's Guide to Avionics 2013-2014 - 14
Pilot's Guide to Avionics 2013-2014 - 15
Pilot's Guide to Avionics 2013-2014 - 16
Pilot's Guide to Avionics 2013-2014 - 17
Pilot's Guide to Avionics 2013-2014 - 18
Pilot's Guide to Avionics 2013-2014 - 19
Pilot's Guide to Avionics 2013-2014 - 20
Pilot's Guide to Avionics 2013-2014 - 21
Pilot's Guide to Avionics 2013-2014 - 22
Pilot's Guide to Avionics 2013-2014 - 23
Pilot's Guide to Avionics 2013-2014 - 24
Pilot's Guide to Avionics 2013-2014 - 25
Pilot's Guide to Avionics 2013-2014 - 26
Pilot's Guide to Avionics 2013-2014 - 27
Pilot's Guide to Avionics 2013-2014 - 28
Pilot's Guide to Avionics 2013-2014 - 29
Pilot's Guide to Avionics 2013-2014 - What's Up With Backup Instruments?
Pilot's Guide to Avionics 2013-2014 - 31
Pilot's Guide to Avionics 2013-2014 - 32
Pilot's Guide to Avionics 2013-2014 - 33
Pilot's Guide to Avionics 2013-2014 - Going Glass
Pilot's Guide to Avionics 2013-2014 - 35
Pilot's Guide to Avionics 2013-2014 - 36
Pilot's Guide to Avionics 2013-2014 - 37
Pilot's Guide to Avionics 2013-2014 - 38
Pilot's Guide to Avionics 2013-2014 - 39
Pilot's Guide to Avionics 2013-2014 - 40
Pilot's Guide to Avionics 2013-2014 - 41
Pilot's Guide to Avionics 2013-2014 - Before & After
Pilot's Guide to Avionics 2013-2014 - 43
Pilot's Guide to Avionics 2013-2014 - Aircraft as Antenna Farm
Pilot's Guide to Avionics 2013-2014 - 45
Pilot's Guide to Avionics 2013-2014 - 46
Pilot's Guide to Avionics 2013-2014 - 47
Pilot's Guide to Avionics 2013-2014 - 48
Pilot's Guide to Avionics 2013-2014 - 49
Pilot's Guide to Avionics 2013-2014 - Cockpit Innovations
Pilot's Guide to Avionics 2013-2014 - 51
Pilot's Guide to Avionics 2013-2014 - 52
Pilot's Guide to Avionics 2013-2014 - 53
Pilot's Guide to Avionics 2013-2014 - 54
Pilot's Guide to Avionics 2013-2014 - 55
Pilot's Guide to Avionics 2013-2014 - Understanding Autopilot Upgrades
Pilot's Guide to Avionics 2013-2014 - 57
Pilot's Guide to Avionics 2013-2014 - 58
Pilot's Guide to Avionics 2013-2014 - 59
Pilot's Guide to Avionics 2013-2014 - ADS-B Circa 2013
Pilot's Guide to Avionics 2013-2014 - 61
Pilot's Guide to Avionics 2013-2014 - 62
Pilot's Guide to Avionics 2013-2014 - 63
Pilot's Guide to Avionics 2013-2014 - 64
Pilot's Guide to Avionics 2013-2014 - 65
Pilot's Guide to Avionics 2013-2014 - Portable Powerhouses, GPS and VHF
Pilot's Guide to Avionics 2013-2014 - 67
Pilot's Guide to Avionics 2013-2014 - 68
Pilot's Guide to Avionics 2013-2014 - 69
Pilot's Guide to Avionics 2013-2014 - 70
Pilot's Guide to Avionics 2013-2014 - 71
Pilot's Guide to Avionics 2013-2014 - 72
Pilot's Guide to Avionics 2013-2014 - 73
Pilot's Guide to Avionics 2013-2014 - 74
Pilot's Guide to Avionics 2013-2014 - 75
Pilot's Guide to Avionics 2013-2014 - 76
Pilot's Guide to Avionics 2013-2014 - 77
Pilot's Guide to Avionics 2013-2014 - 78
Pilot's Guide to Avionics 2013-2014 - 79
Pilot's Guide to Avionics 2013-2014 - Minimal Panels
Pilot's Guide to Avionics 2013-2014 - 81
Pilot's Guide to Avionics 2013-2014 - 82
Pilot's Guide to Avionics 2013-2014 - 83
Pilot's Guide to Avionics 2013-2014 - NextGen Status Report
Pilot's Guide to Avionics 2013-2014 - 85
Pilot's Guide to Avionics 2013-2014 - 86
Pilot's Guide to Avionics 2013-2014 - 87
Pilot's Guide to Avionics 2013-2014 - 88
Pilot's Guide to Avionics 2013-2014 - Repair Stations
Pilot's Guide to Avionics 2013-2014 - 90
Pilot's Guide to Avionics 2013-2014 - 91
Pilot's Guide to Avionics 2013-2014 - 92
Pilot's Guide to Avionics 2013-2014 - 93
Pilot's Guide to Avionics 2013-2014 - 94
Pilot's Guide to Avionics 2013-2014 - 95
Pilot's Guide to Avionics 2013-2014 - 96
Pilot's Guide to Avionics 2013-2014 - 97
Pilot's Guide to Avionics 2013-2014 - 98
Pilot's Guide to Avionics 2013-2014 - 99
Pilot's Guide to Avionics 2013-2014 - 100
Pilot's Guide to Avionics 2013-2014 - 101
Pilot's Guide to Avionics 2013-2014 - 102
Pilot's Guide to Avionics 2013-2014 - 103
Pilot's Guide to Avionics 2013-2014 - 104
Pilot's Guide to Avionics 2013-2014 - 105
Pilot's Guide to Avionics 2013-2014 - 106
Pilot's Guide to Avionics 2013-2014 - 107
Pilot's Guide to Avionics 2013-2014 - 108
Pilot's Guide to Avionics 2013-2014 - 109
Pilot's Guide to Avionics 2013-2014 - 110
Pilot's Guide to Avionics 2013-2014 - 111
Pilot's Guide to Avionics 2013-2014 - 112
Pilot's Guide to Avionics 2013-2014 - 113
Pilot's Guide to Avionics 2013-2014 - 114
Pilot's Guide to Avionics 2013-2014 - 115
Pilot's Guide to Avionics 2013-2014 - 116
Pilot's Guide to Avionics 2013-2014 - 117
Pilot's Guide to Avionics 2013-2014 - 118
Pilot's Guide to Avionics 2013-2014 - 119
Pilot's Guide to Avionics 2013-2014 - 120
Pilot's Guide to Avionics 2013-2014 - 121
Pilot's Guide to Avionics 2013-2014 - 122
Pilot's Guide to Avionics 2013-2014 - 123
Pilot's Guide to Avionics 2013-2014 - 124
Pilot's Guide to Avionics 2013-2014 - 125
Pilot's Guide to Avionics 2013-2014 - 126
Pilot's Guide to Avionics 2013-2014 - 127
Pilot's Guide to Avionics 2013-2014 - 128
Pilot's Guide to Avionics 2013-2014 - 129
Pilot's Guide to Avionics 2013-2014 - 130
Pilot's Guide to Avionics 2013-2014 - 131
Pilot's Guide to Avionics 2013-2014 - 132
Pilot's Guide to Avionics 2013-2014 - Manufacturers/Distributors
Pilot's Guide to Avionics 2013-2014 - 134
Pilot's Guide to Avionics 2013-2014 - 135
Pilot's Guide to Avionics 2013-2014 - 136
Pilot's Guide to Avionics 2013-2014 - 137
Pilot's Guide to Avionics 2013-2014 - 138
Pilot's Guide to Avionics 2013-2014 - 139
Pilot's Guide to Avionics 2013-2014 - 140
Pilot's Guide to Avionics 2013-2014 - 141
Pilot's Guide to Avionics 2013-2014 - 142
Pilot's Guide to Avionics 2013-2014 - 143
Pilot's Guide to Avionics 2013-2014 - 144
Pilot's Guide to Avionics 2013-2014 - Affiliates/Index
Pilot's Guide to Avionics 2013-2014 - 146
Pilot's Guide to Avionics 2013-2014 - 147
Pilot's Guide to Avionics 2013-2014 - 148
Pilot's Guide to Avionics 2013-2014 - 149
Pilot's Guide to Avionics 2013-2014 - 150
Pilot's Guide to Avionics 2013-2014 - AEA Member Company Index
Pilot's Guide to Avionics 2013-2014 - 152
Pilot's Guide to Avionics 2013-2014 - 153
Pilot's Guide to Avionics 2013-2014 - 154
Pilot's Guide to Avionics 2013-2014 - 155
Pilot's Guide to Avionics 2013-2014 - 156
Pilot's Guide to Avionics 2013-2014 - 157
Pilot's Guide to Avionics 2013-2014 - 158
Pilot's Guide to Avionics 2013-2014 - 159
Pilot's Guide to Avionics 2013-2014 - Advertiser Index
Pilot's Guide to Avionics 2013-2014 - Cover3
Pilot's Guide to Avionics 2013-2014 - Cover4
http://www.brightcopy.net/allen/pilotsguide/19-20
http://www.brightcopy.net/allen/pilotsguide/18-19
http://www.brightcopy.net/allen/pilotsguide/17-18
http://www.brightcopy.net/allen/pilotsguide/16-17
http://www.brightcopy.net/allen/pilotsguide/15-16
http://www.nxtbook.com/allen/pilotsguide/2014-2015
http://www.nxtbook.com/allen/pilotsguide/2013-2014
http://www.nxtbook.com/allen/pilotsguide/2012-2013
http://www.nxtbook.com/allen/pilotsguide/2011-2012
http://www.nxtbookMEDIA.com