Grand Rapids vs Dynon - Dynon vs Grand Rapids

Grand Rapids vrs Dynon - Dynon vrs Grand Rapids

I am having a **** heck of a time deciding what I want to do......

I am rebuilding a plane and have decided to change the panel from steam gauges to glass. I am not new to glass however, all these new advances....

Eventually the system design will be for IFR.

Dual Displays - 8-10" - Touch not an issue, Sunlight
External inputs - analog-digital fully able to map the way I want to display?
Charting? Costs associated?

Full Engine management, Engine type...?
Fuel type
Six fuel inputs

Autopilot - High torque servos
Radio interface.. Space might not b an issue; If it is..??

Here's the kicker, I currently have an Allison 250 turboprop or An IO-540 twin turbo that can be installed on the plane (no not an rv, however you all have always had good comments). Yea-Yea-Yea I know all the issues.

How close can I get?

Anyway,

Thanks in advance for any info.......

Both are capable of meeting your needs.
It is like choosing a car from GM, Ford, Chrysler, Toyota, ... (I work for GM so forget about those other guys )

I fly both (I have GRT, I'm flying with an IFR student in his RV7A with a full Dynon package).
I am a GRT fan. I find their stuff rock solid and more than capable.
We have had some minor issues with the Dynon - but nothing that would cause me to not recommend them - mostly installation issues (done by an avionics shop).
GRT got their start with EIS, so I give them a leg up in that department. Six fuel inputs will be interesting with either unit. That one will require some research.
Charting costs - depends on what you want. I do IFR charts on my iPad (Foreflight). The non-IFR GPS database updates are free from GRT - probably the same from Dynon since it is FAA data.
Your IFR GPS is independent of either unit so that is a wash. Both will hook up to the GPS similarly (through an ARINC 429 interface for IFR).
There is enough info on both manufacturer's websites to put together a side by side comparison of features and costs. It's involved but doable.

Dennis hit the nail on the head. But since I used to work for GM and Honda, I have a different bias. I'm driving all Hondas these days.

While I have a preference for Dynon/AFS, it's really almost a flip of the coin.

I can do four fuel source on my AFS EFIS, but I don't know of any that do six. But then I never looked for that feature either.

I do have a preference for using an external AP head for IFR. Both vendors support that option.

I'm not sure I understand what you meant by, External inputs - analog-digital fully able to map the way I want to display? Are you looking for additional annunciators or are you looking for the ability to change the displays. I think MGL is the only one that provides that ability to significantly modify the display. Both your vendors have to capability to annunciate external devices.

For approach plates, Dynon has a slight advantage. Seattle Avionics has been known to sell their charts for a deep discount on Black Friday. I think they offered 2 for 1 last year. I don't recall their offer from this year.

I do like the new bus technology that is now used by both AFS and Dynon. I don't think GRT has anything similar. It does give the AFS/Dynon team a little more flexibility to integrate new technology into the solution.

SkyView General Inputs

SkyView can easily support 6 fuel sensors. The system has over 10 general inputs that can be configured to monitor almost anything. The system can accommodate 4 capacitive sensors and the rest would need to be resistive. Or you could have them all be resistive.

From the Dynon Manual:

Capacitive fuel level sensors are only supported on pins 8, 22, 23, and 31 on the SV-EMS-220/221 D37. Capacitive sensors must output a variable voltage within the ranges of 0-5 volts DC

Dynon also sells a capacitive to resistive converter if needed.

I agree with Bob, Dennis was all correct with the exception of GM. Toyota rules in my house hold.

In regards to the EIFS, I have flown behind GRT and Dynon and for IFR type flying, I prefer GRT by a long shot. If I was going with Dynon, then I would consider Advance as I think it is a toss-up between GRT and Advance.

Sticky,
We do have the ability to support turboprops. It requires some help from us individually, but we're happy to give it. We can display two RPM's, do them in % or RPM, and of course your various temps and pressures.

As also mentioned, we can support 6 fuel tanks if needed. We have 14 general purpose inputs on our engine module that can be configured as needed.

As for charting costs, Dynon gives the USA aerodata (airspace, airports, navaids, obstacles, etc) away for free with a simple download on our website each month. Other charts like sectionals, airport diagrams, IFR HI/LO and approach and departure plates are $99 a year from Seattle Avionics. This is one charge per airplane no matter how many screens you have.

Dynon's COM radio is really small, so I bet you can find a place on the panel. However, if you are really planning for IFR, you need to decide on your GPS/COM/NAV first, since those are often integrated into one, so a COM may not be needed depending on your requirements. IFR in an experimental requires a certified GPS (if you want to use the GPS, including as a DME replacement) so that has a lot to do with your panel. Dynon's display and autopilot fully couples to IFR GPS and NAV radios.

If anyone says that another system is more capable in IFR, I would ask when they made that analysis, and how the system was configured. In the last year we have added a huge amount of IFR features such as the ability to show the full flight plan and approach from an IFR GPS on our screens, a flight director, and enroute charts. Dynon is always updating software so you can be sure a product from us will continue to get better and more capable. Dynon also has the ability to go from a simple VFR PFD only to a three screen, super redundant IFR setup with engine monitoring, mapping, charting, and more, so the configuration is important when making a comparison.

Good luck in your decision and project! If you stick that turboprop in the nose we want a ride

my 2 cents

When I was making that choice (I went with GRT) I eliminated Dynon for one reason: Their attitude solution would fail if pitot-static data was lost. I personally did not consider it adequate for ifr if a pitot blockage would cause the attitude indicator to fail. Since then they have come up with a software fix, which, if it detects a complete pitot blockage, switches to gps ground speed. (So now attitude data depends on having gps data OR pitot data). Whether or not you consider this adequate for ifr is your call.

Dynon's reliance on pitot input for attitude has been mitigated by the ability to use GPS speed. That was done some time ago (2-3 years?) so I'd say this portion of the argument doesn't carry as much weight as it once did. The GRT AHARS has never used airspeed as an input to the attitude equation.

BTW, I have flown legacy Dynon equipment in my own airplane for years, and my new aircraft has GRT. Both are top notch in the support department. Not that I've needed any hardware support on either, but both have been quick to answer questions and provide guidance. Can't really go wrong with either.

both are great outfits

making great hardware. The tiebreaker for me was Dynon's stance toward (against) synthetic approach to user waypoints (private runways). Got the HXr and won't look back. Did a feature comparison on similarly priced D6 and Mini-X, sold the D6 at a loss and turned it into a more capable Mini that takes 1/3 the depth behind the panel and has a moving map and synthetic vision (are you kidding me - I feel like Buck Rogers )

No doubt Dynon will strike back with another offering soon. Competition makes these magic boxes better for all of us. I'd suggest buying at the last possible minute, given the dynamic market competition.

-Stormy

Can we add the G3X to this comparison. I am building a 14 and want it to be IFR so I expect to install a Garmin 750 for nav/com. Given this I am looking at G3X because it will communicate with the 750. But, I want to be sure it compares well with GRT and Dynon. I would love everyone's thoughts.




Dues paid this year
RV 14 N4114A reserved
Wings done, tail done

Jim Slesser said:

Can we add the G3X to this comparison. I am building a 14 and want it to be IFR so I expect to install a Garmin 750 for nav/com. Given this I am looking at G3X because it will communicate with the 750. But, I want to be sure it compares well with GRT and Dynon. I would love everyone's thoughts.




Dues paid this year
RV 14 N4114A reserved
Wings done, tail done

Click to expand...

Because Garmin is the only (ifr certified gps) game in town, all of the EFIS units will communicate with the garmin gps boxes.
Now, everyone who bought a G3X will tell you what a great decision they made.
Everyone who bought a GRT will tell you.....
Everyone who bought a Dynon....
You get the idea.

BobTurner said:

Because Garmin is the only (ifr certified gps) game in town, all of the EFIS units will communicate with the garmin gps boxes.
Now, everyone who bought a G3X will tell you what a great decision they made.
Everyone who bought a GRT will tell you.....
Everyone who bought a Dynon....
You get the idea.

Click to expand...

Bingo! Everyone's child is the cutest, right?!

One quick point...at the moment all the EFISes will communicate with the GTN only one way (receive data from it), but at the moment the G3X is the only one that can push data TO it....though there are a good number of other TSO GPSes available, they are either more expensive, old, not as user friendly, etc...so for the time being Bob is right on as usual.

From an EFIS perspective, they are all good, but Dynon and Garmin have clearly become the two most dominant in the market in almost every way.....both in the Experimental and LSA world. They also have the largest support structures behind them (finances, resources, installed user base, etc..).

That of course doesn't mean there isn't space for others in the market to remain viable. For example, the Twins really work well with the GRT, so do jet/turbine and/or alternative engines. Heck, most of Team Aerodynamix uses them!

I try to be Switzerland in this debate, but it's clear to my business selling the number of them that we do which are the most popular based on real data and not anecdotal info.

Paul suggested we do another EFIS article on this subject for Kitplanes like we used to....appears it may be time! For now, come by our shop and play with them all anytime!

Just my 2 cents as usual.

Cheers,
Stein

I was reading the Garmin website trying to find out the cost/yr. It seems that their is an annual cost. Dynon and others do not charge except for a one time license.Updates are included in that license. Those that have the garmin in their planes what is the annual cost, if any not including the XM weather, and are there update fees?
thanks
Dave

SteinAir said:

. . . . <snip >For now, come by our shop and play with them all anytime!

Just my 2 cents as usual.

Cheers,
Stein

Click to expand...

Highly Recommended!

Do any of the sport EFIS have automatic brightness to ambient light? (like the TSO coms and GPS units do)

F1R said:

Do any of the sport EFIS have automatic brightness to ambient light? (like the TSO coms and GPS units do)

Click to expand...

Absolutely...both the Dynon and Garmin have photo-sensors in the screens. Also, both can be externally managed through a dimmer if you desire quite easily by just hooking up a dimmer. Others make you press a button in a menu, so on and so forth (of course you can do the same through the Dynon and Garmin), but the photo sensors are really quite nice and slick verses navigating a menu to do it (as external dimmers are just as easy). I believe both Dynon and Garmin will allow just about any kind of dimmer to drive the screens as well...which makes it easy (no special or expensive PWM dimmer required)!

Cheers,
Stein

I personally prefer panel mounted dimmers on large light sources like efis screens and large displays, when I'm flying at night I like the panel as dark as practical and setting slopes and such to get it just right is difficult to suit my personal taste, easier to just twist a knob. I find the small stuff like radios, xpdrs etc are generally fine with their internal dimmers though.

As someone who has been following them all for 15 years but the only skin in the game I have is a D10A that I bought used, and a Garmin Aera 500 that I have come to realize is abysmal for an RV, I think the G3X is the system i'd like to have, but only slightly edging out ahead of Dynon.

The GRT is the system i'm most likely to end up with, as I live in Canada... Canadian map data and updates for either G3X or Dynon are, to my understanding, prohibitively expensive.

SteinAir said:

Absolutely...both the Dynon and Garmin have photo-sensors in the screens. Also, both can be externally managed through a dimmer if you desire quite easily by just hooking up a dimmer. Others make you press a button in a menu, so on and so forth (of course you can do the same through the Dynon and Garmin), but the photo sensors are really quite nice and slick verses navigating a menu to do it (as external dimmers are just as easy). I believe both Dynon and Garmin will allow just about any kind of dimmer to drive the screens as well...which makes it easy (no special or expensive PWM dimmer required)!

Cheers,
Stein

Click to expand...

Just to be clear, the GRT screen brightness can be controlled with a simple, low current voltage source (nothing special required). And I do find that much preferable to pushing the buttons.

Snowflake said:

The GRT is the system i'm most likely to end up with, as I live in Canada... Canadian map data and updates for either G3X or Dynon are, to my understanding, prohibitively expensive.

Click to expand...

Rob,
Canada data is not free no matter what system you have. I do not believe up-to-date Canada data is free or less expensive on GRT over any other EFIS. Dynon does support PocketFMS which has great Canadian data for only 119 euros a year.

If someone knows of a free database for Canada that other EFIS units are using, please point us that way!

GRT Avionics Uniquenesses

Some customers asked me to reply to this thread today, but I see that some of the questions have already been answered with regard to GRT Avionics.

There would be no issues using GRT in this airplane, including with respect to the Allison turboprop (we have extensive experience with instrumenting these engines), the six fuel tanks.

When it comes to IFR, I of course prefer an AHRS like ours, that does not require air data or GPS to provide attitude, as was already pointed out. (Our AHRS will operate without any aiding, and although its does use airspeed when it passes our reasonableness testing, it is not dependent upon it to the extent that bad air data will reduce the integrity of our attitude data.)

Another difference is the architecture of our EFIS does not rely on a bus to transmit data between devices. We use separate serial connections to each device, so that a failure of that connection only affects the one device it is connected to.

Other significant differences is that the GRT systems allow you to choose from a variety of radios, transponders, etc. We don't tie you to just our brand, and our openness means we are quick to interface to new equipment as it becomes available.

Finally there is the android app, that allows for menu driven radio tuning, flight planning, and provides a primary flight display (great for tandem seating airplanes).

I hope that helps. I didn't mean to sound like an advertisement. My intent was just to point out some of the differences between us, and others.

Greg Toman

Greg - two questions for you, if you please...

1) Is it possible to use a panel-mount PWM dimmer to dim a GRT Horizon HS EFIS? If so, I'd like to know the secret sauce, please!

2) For those of us who have chosen to go with an independent TruTrak autopilot (Vizion 385 in our case) with Arinc 429 input from a Horizon HS or directly from a Garmin GNS480, is it possible to send baroset data from the HS to the Vizion 85, as is the case with the Garmin G3X EFIS products? Lucas previously posted that he wasn't sure whether other EFIS besides the G3X could do so. It would be great if I had one less barometer setting to enter.

While I would like nothing better than to upgrade our HS to an HX it's just not in the budget (although that budget did allow for the steam gauges to be replaced by a Mini-X!). I'm still trying to find a more economical means of replacing the HS with a 6.5" HX as that would fit our panel perfectly and would truly be the icing on the cake.

1. A Pulse Width Modulated dimmer will not work directly with the HS. The HS just wants a simple, variable dc voltage, like a simple potentiometer would provide. If you insist on using a PWM circuit, you can build a RC circuit to filter the PWM signal down to an average dc signal.

2. I have the Trio Pro, not the Tru Trak, but I think they operate the same when driven by the HS - namely, the HS provides the vertical commands via ARINC directly to the autopilot. The altimeter setting only needs to be inputted to the autopilot if you run the autopilot in stand alone, independent of the HS, mode. At least that's how the Trio works.

Bob - thanks for the suggestions. I have a 4-channel pwm dimmer already installed; the channel previously used to light the steam gauges remains available to dim the EFIS. I'm definitely not a big fan of external discrete components in the form of an RC network, but will give this some consideration.

As for the baroset, going with an independent autopilot controller was done to ensure the ability to fly the airplane independent of the EFIS, so at the moment it looks like manually setting the baroset on the autopilot will be part of the pre-takeoff checks. In retrospect, having the EFIS push the baroset to the autopilot could put me in the position of not being fully aware of the baroset in use by the A/P should the EFIS data not make it through. Seems like consistently manually setting the baroset is likely the better way to ensure the pilot always knows the baroset being used by the A/P.

Sometimes in asking a question here one has an opportunity to do a double-check on one's own thinking. That's always a benefit!

Thank you to all who have responded!

I recently found a question sheet I used 7 years ago and figured I would post it here. Some of the questions I already have answers to however since times and equipment has changed, I would like to get the answers to those I don't. I have narrowed down the search to either the Dynon or the Grt, Grt or Dynon..... The Garmin does not allow for turboprop operations.

The basics: As mentioned I am rebuilding my second plane.
-IFR certified
-Dual Efis
-Backup Efis
-Auto pilot
-Allison exists on the plane, may be changing to IO540 twin turbo (less expensive)

EFIS QUESTIONS

1-Is the display Sun-Light readable?

2-Is the display dimmable by an external knob?

3-How many external inputs can I have? I want to have a screen that will tell me what’s turned on or off.

4-What do I have to connect to get the basics: Attitude, Compass, and Airspeed & Vertical Speed? Already been answered....

5-Can the Gamin 650 – 750 be controlled by the efis? If so to what extent?

6-Charting…? IFR / VFR

7-What does the interface wiring diagram look like for the Efis, Eis, GTN 750/650, GTX-330, TruTrak Vizion or Sorcerer? (Link will be fine if one is available if not, no biggie). I had to change the part numbers.......

8-If I decide to purchase the second ahrs later, will the price be different than the package price?

9-What is the efis configuration difference between the Allison and the IO540

10-How many external Efis inputs can I have? What types, analog-digital. Can I map these inputs to the display? Can I configure the display with my own diagram?



EIS QUESTIONS

1-AHRS – (Aiding- Input from external sources; Pitot static & gps)
- Is this better with aiding or without?
- What will happen without the aiding?
Already Answered.......

2-What is the max air speed of the ahrs?

3-How many fuel inputs? What is the configuration? Capacitive – resistive? How many of each? Need six since this rebuild has six tanks (212 Gallons)

4-Can I see two voltage readings on the display? Buss 1 and Buss 2

5-What is the EIS configuration difference between the Allison and the IO540.

6-Will the efis interface with the Electronic International MVP-50(T)? Main reason is the USB output to engine mapping software. Does the efis have this so I can eliminate this device?

7-How many external EIS inputs can I have? What types, analog-digital. Can I map these inputs to the display? Can I configure the display with my own diagram?

8-What type of sensor is used for the tachometer?

9-What type of sensor is used for Fuel Flow? What are the diameters of the input and output ports? Can I get a calibrated flow sensor that has 1/2” ports and thru flow?


EFIS QUESTIONS

1-Should I use the internal autopilot or go with an external auto pilot?

2-What are the torque ratings on the servos (Need torque)?