Date: Sun, 02 Nov 2003 21:21:53 -0500
From: John & Paddy Wigney <johnwigney@worldnet.att.net>
Subject: Dynon EFIS
From: <a class="moz-txt-link-abbreviated"
href="mailto:DJA727@aol.com";>DJA727@aol.com
Subject: Europa-List: Dynon EFIS
-- Europa-List message posted by: <a class="moz-txt-link-abbreviated"
href="mailto:DJA727@aol.com";>DJA727@aol.com
Hello Group! I am now getting dangerously close to purchasing the Dynon EFIS
system.
Due to a lack of vacuum, I am now committed to an electrical attitude system.
The Dynon will fit right in and allow me to have attitude info even when
the engine is shut down in flight (an every other flight occurrence in the Mini
U2). I would love to get feedback on anyone's experience with that EFIS before
I make the big move. Obviously, it would be great to have a bigger display,
but the Europa's panel space is limited and I am leaving the mechanical
altimeter,ASI
in for back-up. I will be replacing my vacuum ADI with the Dynon. The
price is barely more than an electrical attitude gyro and if it works as they
say it will, my days of manually setting the heading gyro will be over.The EFIS
looked pretty good to me when I saw it at OSH. The attitude info seemed to
be very smooth as was the heading. I don't know how the airspeed or altitude
information works, but I do have the mechanical back
-up.Thanks for your help in advance. Dave A227 Mini U2
Hi Dave,
I installed a Dynon EFIS in July 2003, and I now have about 50 hours of
experience
with it. Not all of this has been satisfactory, see below.
Background is :-
* My panel is all electric since I have a Whirlwind constant speed prop and the
hydraulic governor occupies the vacuum pump pad on my 912S.
* I have approximately 200 hours time on my plane and for the first 150 hours I
had an RC Allen electric gyro horizon. This unit was totally unsatisfactory
despite
being sent back to the factory 3 times for repair. After 5 minutes of flight,
the horizon showed a descending left bank while straight and level. Factory
overhauls failed to fix the problem, despite verification on my bench that
the gyro appeared to be OK.
* I have a standard 6 pack instrument arrangement of airspeed, gyro horizon,
altimeter
on the top row and turn cordinator, directional gyro and vertical speed
indicator on the bottom row.
* I designed my panel to be IFR capable and have just recently started IFR
training.
My basic objective is to improve my pilotage, I have no plans to go flying
around in clouds on a regular basis. If anyone has plans to do heavy IFR flying
in poor conditions, I do not believe the Europa is appropriate.
* Note that Dynon recommends that the EFIS-D10 is not used as a primary flight
instrument for IFR flight. This means that the plane should be equipped such
that
any single point failure - including the failure of the EFIS - will not
jeopardize
the completion of any flight. Use of the EFIS as a horizon only meets
this criterion.
The installation of the Dynon EFIS was relatively straightforward and I use mine
with only the horizon feature displayed. Note that it must have the pitot and
static connections, even if you choose not to display airspeed and altitude,
etc. I understand from Dynon that the unit will not work correctly without these
since the algorithms depend on having a speed input. Beats me. Anyway, my
first flight tests showed a similar problem to the gyro horizon. It showed a
level
horizon on the ground but showed a left bank while flying straight and level.
It also showed a left turn when stationary on the ground. After discussion
with Dynon (Yes, there is a glitch in the software !) and loading the latest
software (Version 1.5.0), this problem was fixed. I must say I was surprised
that such a basic problem existed on an item of this type.
I have only recently found another problem during my IFR training. During a
non-precision
approach which descends with a glide slope significantly higher than
the normal 3 degrees (flaps and gear down, ~ 900 fpm descent rate, ~ 80 kts,
steady nose down between 5 and 10 degrees) the Dynon horizon falsely oscillates
up and down and even briefly shows up to 5 degrees nose high. During a precision
IFR approach with the normal 3 degrees glide slope (flaps and gear down,
~ 400 fpm descent rate, ~ 80 kts), the nose down horizon is steady and gives
a correct representation. I have spoken to Dynon and they advise that they have
not received any comments from other customers on this type of problem. At the
moment, I have not decided on my next step. This horizon saga has been the
only significant problem on my plane and I am a little weary of removing the
instrument
for whatever reason. Any comments and suggestions would be appreciated.
Finally, I have been unable to obtain a satisfactory calibration of the Dynon
EFIS
internal magnetometer to obtain an accurate compass heading readout. This
is not surprising since the calibration depends on having a magnetically neutral
location and I have adjacent electric motors in the directional gyro and the
turn cordinator. A hand-held compass is deflected in that region of the panel.
I am quite sure the remote magnetometer option would fix this problem but I
already have my DG and regular compass so I do not plan that.
I have no desire to give the Dynon EFIS a bad name. If I can find the fix to the
latest glitch, it will definitely meet my needs.
If you wish, I can give you my contacts at Dynon.
Cheers, John
N262WF, mono XS, 912S
Mooresville, North Carolina
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