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Zulu Alpha
3rd Jan 2006, 12:50
Does anyone have any experience of electronic artificial horizons?

I have seen both specific units and also ones that work with PDAs.

I am interested in how well they work and how reliable they are for use in a permit aircraft.

Many thanks

Mark 1
3rd Jan 2006, 14:20
I presume you really mean electronic and not electric horizons (the difference is lost on a lot of people).

I have come across the Dynon D-10 unit which uses solid-state gyros (RLGs) to provide the attitude and heading reference system in conjunction with a flux-gate compass to update the heading.

There has recently come onto the market a "pseudo-horizon" which seems to use turn-rate for bank and vertical speed for pitch. I see this as having potential dangers for mis-interpretation.

The Dynon unit has had lots of good reports and looks like a good option, especially for a small panel.

I believe the electronic gyros are essentially rate-gyros, but use electronic integrators and long interval averaging to correct for drift.

Zulu Alpha
3rd Jan 2006, 14:45
Yes, I do mean the electronic solid state ones. The PDA ones look cheaper, easily installed and movable but I'm not sure how well they work.
I have had several PDAs and some worked well and some locked up and I wondered whether anyone had experience of them as a horizon.

Rod1
3rd Jan 2006, 17:01
I have the PDA version of the PC Flight Systems e-gyro installed in my as yet unfinished MRC-01. Hope to have it in the air in the next 4 – 8 weeks. Have flown with an E-Gyro in a CT and was very impressed, but do not try to run the map s/w as well as it will make the system unstable.

PC flight systems have sold a lot of units and have a complete range of options from “specialist” all in one to PDA systems.

If you put WWW the full name with no spaces then the .com you will find full details! (I understand we cannot post direct links anymore).

Rod1

Hen Ddraig
13th Jan 2006, 12:14
I have a Dynon D10 installed with about 5 hours experience in use. A brilliant piece of kit, not just an artificial horizon, but also HI,ASI,Alt,Rate of climb,Angle of attack,OAT,battery state and the ability to hold 5 check lists. Internal battery provides 2 hrs backup and now available with a 7 inch screen.
With the Dynon the only other requirements are Backup Magnetic compass, Altimeter and ASI.

Time to spare, go by air

Hen Ddraig

Confabulous
13th Jan 2006, 14:39
I take it that for angle of attack and oat you need to install electronic sensors? 'Twould be great to have alpha info - could save lives too :cool: :ooh:

stiknruda
13th Jan 2006, 15:48
Oh no ZA, this is not a ploy to allow you to use your IMC rating and get above the clouds to practice for Indeterminate later this year, is it?:\ :\



Stik

Zulu Alpha
13th Jan 2006, 16:08
What a great idea!!

Actually its to help me get to competitions.

Not sure about indeterminate as I've been grounded since 20 Nov as prop is away for overhaul at Skycraft and there is no ETA yet.

See you at Sywell Sat?

Hen Ddraig
13th Jan 2006, 17:56
Dynon supply OAT probe and two port pitot for AoA, also available is a remote compass module which can be mounted well away from the large lumps of metal found behind the prop.

Time to spare, go by air.

Hen Ddraig

Keef
15th Jan 2006, 13:30
I'm very interested in these for an entirely different reason.

Just how accurate are they? I ask, because a solid-state rate gyro that I was looking at for another application had quoted short-term accuracy of one degree per second, which wouldn't be much help in an AI. It also had "output noise" equivalent to +/- 3 degrees or so.

Some of that could be taken of by using integrators and averaging, but I'm still apprehensive.

To get the sort of accuracy needed for IFR flight, the inference was that you need either electric (mechanical) gyros, or ring laser ones. The latter are excellent, but scarily expensive.

So how do these devices do it, or are they also scarily expensive?

Zulu Alpha
15th Jan 2006, 22:02
Keef,

The D10A artificial horizon from Dynon which goes in your panel is around $2200 see http://www.dynonavionics.com

Their website implies better accuracy than you quote for the sensors. Not sure how they do this but they mention three angular rate (gyro) sensors; three accelerometers and three magnetic field strength sensors. Maybe there is some clever software trickery to keep it all from drifting.

I have also seen some artificial horizons that use a PDA with a cable to the sensor box. These can then be used in the Aircraft with a piece of velcro. I am interested in how good these really are. I have met one person who had one in his Extra and he said it was very good. I was hoping to get some pruners who could provide additional user feedback

slim_slag
15th Jan 2006, 22:19
keef, I think there are a few solid state devices out there which have met FAA TSOs. Never used one but they look really neat.

Mark 1
16th Jan 2006, 12:51
The main enabler for these devices is that the same sensors are being used in cars for stability control. This has allowed volume production of sensors to bring the costs down.

chrisN
16th Jan 2006, 15:09
Keef, I didn't know you were interested - if you want to borrow my PDA-linked PCEFIS you are welcome to try it. System originally cost about £1300 for the EFIS box and leads, say £300 for PDA if one didn't already have one, and £2-300 for a Garmin 89 or 90 for the GPS driver (it might work with others too, else could need a different lead for the GPS bit if you want to display that at the same time as attitude data).

Regards - Chris.

Keef
16th Jan 2006, 23:55
Thanks Chris - I'm working on a project to develop non-visual attitude, heading, etc information. I started by looking at piezo gyros, but the cheapo ones weren't up the job. I'm about to get stuck in with an (old) electric turn and slip with autopilot outputs. I may take you up on your offer later if that doesn't do the job.