OK Now I have 2 Autopilot installs working at the same time :-)

[Cliffy]

In a previous thread about the D10A that a friend wants to install in his T-18 all the help I got here has made him decide to move forward on the project. Looks like it will be a straight forward deal. He has the D10A in hand and is cutting metal.

Now I have a new issue for my airplane. THIS IS STRICTLY AN INTERIM INSTALL UNTIL THE DYNON AUTOPILOT GETS MOONEY CERTIFICATION FOR SHORT BODIES-OK? As I would much rather have the system self-contained all Dynon. BUT I am going to install a BK/TT Aerocruz 100 in the interim. I really need some kind of autopilot now.

I can get by with just the internal A/P functions on the TT A/P (track, heading with limitations on no external ADHARS, and the alt hold, A/S climb and rate decent) BUT it would be nice to at least have left/right nav from the magenta line on my HDX as a minimum. (This is a strictly VFR airplane as I'm way too old to be doing hard IFR SE anymore). I'm looking to do the absolute minimum install now as it will be removed and replaced as soon as the Dynon system is available.

In looking at the wiring for the Dynon and the TT A/P I see Dynon has 4 pairs of Serial connections of which I think I have used 3 pair and the TT A/P has one "IN" connection wire for Serial data, no "OUT". In looking at just the minimum can the serial data use just the one wire from the HDX and provide the TT A/P with lateral steering leaving the TT control head to handle all the vertical driving?
It would be nice to have the TT follow the magenta line even if I'm not interested in GPSS at this time.

If I have used all 4 serial ports (I have to check) I understand that the serial data line can be split and "share " the stream with another consumer of the data (TT A/P) Is this correct?

Looking forward to hear what you all have to offer as this is a great forum!!!

 

[jakej]

Generally the RS232 or NMEA data out can be split around 4 ways & you can configure the Dynon port for basic or full/advanced data output - not sure if the datastream will do what you need ,maybe support will chime in here ? Would be useful to know for 'Experimental' market anyway.

 

[Cliffy]

Thanks I thought I read that the Serial stream can be split and I have read about
Advanced and Basic A/P output but I am digging into it more today
I would think that if the TT can listen to a number of different handheld GPS units
then it can (in a similar way) listen to the OUT of a Dynon. But this is just an assumption
on my part.
I wish someone had just a very simple wiring diagram to connect the BK/TT A/P to the HDX
Life would be simple then.
As one who gets down in the weeds on esoteric subjects, in order to further my understanding,
I just read a paper on NMEA that was quite interesting

What Exactly Is GPS NMEA Data? - GPS World

You may have heard about “NMEA data” with respect to GPS. NMEA can be confusing because there are a few NMEA messages, not just one.

www.gpsworld.com

 

[Flo]

Hi Cliffy there is actually an official document from trutrak / BK how to let the Dynon drive the trutrack - Duncan will send it to you on request - it is really only this single wire.. all the best, Florian

 

[Rhino]

I'm no expert, but I'd probably question the legality of using a non-approved configuration in a certified aircraft.

 

[Flo]

I'm no expert, but I'd probably question the legality of using a non-approved configuration in a certified aircraft.

Well the Dynon / Trutrak interface is documented by the manufacturer of the AP so I would assume it is legal? Only thing it does it gives altitude and heading bug data from the Dynon to the AP and it follows the flight plan from the HSI …

 

[Cliffy]

What's non-approved? Its a serious question on my part.
The autopilot is approved for the Mooney and it is designed to use a variety of GPS inputs from non-WAAS
to full LPV approach certified navigators IF GPS navigation is desired
In my case as a strictly VFR operation I only need lateral nav that is shown on the Dynon non-IFR GPS depiction (same as
any hand held GPS unit that can be hooked up to it).
IF I decided to install a certified IFR nav unit then I would hook it up to that. But that is not going to happen as long
as I own this airplane.

 

[Cliffy]

Hi Cliffy there is actually an official document from trutrak / BK how to let the Dynon drive the trutrack - Duncan will send it to you on request - it is really only this single wire.. all the best, Florian

Thanks I didn't know that I'll for sure look into it.

 

[Rhino]

I only mentioned that because it's my impression the Dynon STC only covers the configurations they submitted for approval. As I said, I'm no expert on that, but it makes me wonder what kind of leeway is allowed for adding a different autopilot. The FAA can get mighty picky about stuff sometimes, even when it makes no sense whatsoever.

 

[Cliffy]

OK Now I understand your position and it makes sense as I try to figure this out.
I'm only trying to treat the Dynon as I would any say portable GPS to drive lateral steering on the TT A/P
I don't have a GPS WAAS unit only the Dynon system so I may not need the switch to switch the 429 data on and off.
I would guess that "reading " the OUT serial data from Dynon would suffice as any approved portable unit Serial data
I have found the manual for approved GPS nav units and as I/we suspected the Dynon alone is not included unless the manual
has been updated and not on line (I'll contact Duncan as Florian has suggested). There is a way (looks easy) to get it approved if it is not already.
It looks like it can just use a serial line in to a pin, as they do for many approved non-TSO handheld units to drive the A/P.
Calling Duncan tomorrow Thanks for all the input guys I appreciate it.
I realize I'm a dinosaur in a digital world. I can install KX155s easily as they are from my time. This digital stuff??? Hmmmm

 

[Rhino]

Kind of wish I could be there to help. I've done both analog and digital systems, and always found it fun. Getting kind of old and decrepit to crawl around in airplanes though (mostly decrepit).

 

[Cliffy]

I know how you feel This will probably be my last trip down the install line also.
Did some radio revisions on this airplane a few years ago (all analog) but had the HDX
install done by a shop. This A/P install for me is just for fun. Its fairly simple

 

[Cliffy]

I've got a document from Duncan on hooking up the A/P to the HDX and as I suspected it is only one Serial wire.
I may put a disable switch in that line so I can run the A/P isolated if I want.

 

[OgieOglethorpe]

So you're installing the BK Aerocruze 100 in a short body Mooney despite it not being on the AML? Or did something change? BK is not listing the mooney anywhere but I do see the manual to install it?

 

[Cliffy]

So you're installing the BK Aerocruze 100 in a short body Mooney despite it not being on the AML?

Educate yourself. No other comment necessary. Not going down this rabbit hole on a troll.

 

[OgieOglethorpe]

Edited as I did look for the AML. Mooney wasn't listed on BK's site. Pacific coast says STC pending for the mooney. I thought thats why all the Mooney drivers wanted the dynon. Don't think I've ever been called a troll by someone with a more recent join date and fewer posts than me.

I wish you luck with your install.

 

[Rhino]

That's the kind of thing I was worried about, Cliffy. I'd hate to see you expend all that time and effort, only to find out it isn't legal. I'm not advocating you abandon the effort. Personally, I'd love to see the final answer on the serial data. But you might want to make sure it's legal first.

 

[Cliffy]

Let's set the record straight
I've been a licensed A&P since 1967 I've been professionally trained on everything from 747s down to J-3s in those 6 decades
I hold the FAA Charles Taylor Award for 50 years of safe A&P work.
Sorry to be terse but I've been around the block a few times in my career.
I take great umbrage with Os comments None of that slanderous verbiage was necessary.
Break time!

 

[Rhino]

I think you're looking at this the wrong way. The prevailing opinion among most installers is that something has to be in the STC/AML to be legally installed in a certified aircraft. You appear to be stating that isn't true, and your experience puts you in a very unique position to provide some sorely needed knowledge and guidance here. So please, help educate us. If this is true, it opens doors for a lot of people who thought those doors were closed, locked, barred and welded. You seem to hold some very valuable knowledge that could help a lot of people. Please don't assume we're attacking you when we aren't.

 

[OgieOglethorpe]

Frankly I have no Idea what was slander in my comment. If I made a false statement, please correct me. Its why I asked if something changed in my original post. I was in no way insinuating you didn't have the ability to pull off the install. Merely questioning how in a certified craft given the arcane FAA approval process