TruTrak ADI for IFR?

I think I may have goofed up here on panel planning... my original plan was for a basic IFR panel in my -8; have the usual steam gauges, no vacuum system, was planning on a Dynon for ADI and compass/DG duties. Now comes the new ADI from TruTrak; looks like a lotta bang for the buck, so I ordered that instead (still 6 weeks away).

My question is, since I have no DG, will the TT ADI with its GPS track display (not compass heading) suffice for IFR operations in lieu of a "gyroscopic direction indicator (directional gyro or equivalent)" as stated in 91.205? Anyone have any thoughts on this? I'm starting to wonder if I should cancel the order and go back to the Dynon with its internal compass/DG.

Thanks!
John
-8 QB finish kit/wiring/panel

I looked into that myself, and the way I read the regs, you still need to have a conventional compass.
Even if not required, it still makes sense to have a wet compass "just in case".

While the GPS DG would always be better and more accurate (and with no swing) in actual use, I would sure be nice to have a wet compass to check against once in a while.

My .02

oops, forgot about that little detail; I do have a wet compass, along with an ASI, Alt, VSI, T&B.

"gyroscopic direction indicator (directional gyro or equivalent)"

So, your question rephrased is " Can a GPS heading substitute for a DG "?. I'd sure like to know the answer to that also.

My Lowrance 500 is set to display "magnetic". If the wind isn't blowing too hard ( and the dg isn't precessing), the GPS and DG agree very closely.

I might dare to suggest that it's time to re-write 91.205 to get rid of the de-facto dg reference. I'm not sure I see a reason to have a dg anymore.....

John

The word "equivalent" seems to give a lot of leeway.
The term "gyro" itself is short for gyroscopic which would imply a rotating mass based instrument, but since you can use an "equivalent", it doesn't sound like you need a mechanical gyro.

Since a GPS based "DG" is not only equivalent, but better in actual use, then a true gyro would not be needed.
At the same time, the wet compass serves as backup to either a gyro OR the GPS/DG so you should be good to go.

John_RV4
My Lowrance 500 is set to display "magnetic". If the wind isn't blowing too hard ( and the dg isn't precessing), the GPS and DG agree very closely.
John

Click to expand...

Using your portable Lowrance as your DG might present another problem in that you might have a hard time getting it approved for IFR use being that's it's a portable unit.
That's a whole 'nuther can of worms.

not a portable

I wan't thinking of using a portable. Just pointing out that if you dumb down a GPS, it can approximate a DG reasonably well .

It would be interesting to know if people are getting IFR cert w/out dg and what they are using to provide heading. I bet this is one of those areas where who does the inspection dictates whether it is "good" or not.

John

I was under the impression that a DAR will grant your airworthiness cert for 'day VFR only, unless properly equipped for night/IFR'. meaning that you only get airworthiness for day VFR and it's up to you to equip your plane properly for night/IFR, and you're allowed to fly night/IFR if you do so (without additional red tape)... Do I have this wrong?

Dynon, ADI

When in IMC I really like redundancy. So we're putting the Dynon in our RV-8 as primary and the ADI as secondary (replacing the turn coord. first planned). The TruTrak Digiflight II gives an independent "DG" using either GPS or magnetometer info for trk/hdg. Since all systems are a little different, 3 simultaneous crashes seem very unlikely. The ADI is so new (even with an uncontested patent per their promo!) that I wouldn't entrust my life and my wife's to it just yet. Just back from 2 days at OSH and everybody I talked to with a Dynon says it's been bullet proof. What do you think? The last recourse is the panel page on the Garmin 296. We've written here before that works for reasonable IFR control all by itself (two of us have found this to be OK). Has anybody else tried it? Bill

Dynon and backup

Bill,

In my IFR -8, I'm putting the Dynon as the primary, and I have an E Gyro-2 from PC Flight Systems (http://pcflightsystems.com/EGYRO2.htm) as the backup. Additionally, I've got the Digitrak and Altrak, and just because I'm anal, I've got a TSO'd Turn Coordinator in case all three above fail, which is not likely, so after I get some mileage on the Dynon, the EGyro and the Trutrak, I'll probably get rid of the TC.

Art in Asheville

Art in Asheville

Art: Have you tried out the egyro2? If so, how do you like it? I know it's a 2 1/4" guage but the face and bank angle lines look real small. I was considering ordering one, but would like to hear from someone who has seen it up close. thanks.

Egyro

jack,

I've been flying the Egyro velcro'd to the panel in my Mooney while I finish up the RV. The Mooney panel is farther away than the RV panel, and I have no trouble seeing it at all, the pixels are bright, a great little unit. Aviation Consumer did a review on it, forgot what issue, was probably a year ago. They liked it for a backup, flew it in a Citabria that had no AI or TC.

PC Flight Systems is based out at Leeward Air Ranch in Ocala, the company owner is an RV a tor. Maybe he'd let you fly in and try one out before you buy, just a thought.

Art

IFR Cert

"I was under the impression that a DAR will grant your airworthiness cert for 'day VFR only, unless properly equipped for night/IFR'. meaning that you only get airworthiness for day VFR and it's up to you to equip your plane properly for night/IFR, and you're allowed to fly night/IFR if you do so (without additional red tape)... Do I have this wrong?"

I think this is basically correct. An IFR certification is done by an avionics shop and involves a test and cert on the Xpndr/Encoder, the static system, and the altimeter. Must be done every 2 years. Also must have a VOR test every 30 days if using the vor for an approach. Other than that it is just as stated above--day/vfr unless equipped in accordance........

Sam Ward