I am sure this issue has been discussed, but cannot find the thread. Benefits of Dual Screen G3x vs single screen G3X with panel mounted 696? I guess the real-estate for engine monitoring and lack of redundancy if the single screen goes down are the obvious points, but having ONE XM subscription on a portable device that can be used in any plane and portable for flight planning would be useful. I have not been successful finding a good explanation on this one. Any answers would be helpful. Seems like the 696 is a good backup for almost anything but engine monitoring.
Van's Air Force
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Single Screen G3X
- Thread starter R7237
- Start date
I already had the 696 with AirGizmo mount and had been saving for an EFIS for over a year. The single GDU 370 was all the budget could stand so my panel is a composite of the GDU 370 and GPSMap 696. I still have my EIS4000 engine monitor as I have to replace several of my pressure transducers before I can move the engine monitoring over to the G3X. I am completely satisfied with all that I could afford for this go around.
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Do you loose anything by this setup? Seems like you can take your XM subscription service with you everywhere you go and still have a MFD next to your single screen GDU 370. You can flight plan from the hotel room and plug into the plane and go. Seems like this may be a better choice than the two screen option. And if you do have complete electrical failure, you always have 8 hour battery in the 696. Am I missing something?
The G3X system is designed around two or more displays for the best user experience. One display will certainly work, but it can be cramped to display all that information on one screen. Maybe if Marc Cook is reading this he can chime in with his comments, as he had a single-display system that he later upgraded to two.
Also, you don't get the same level of seamless integration between a single-screen G3X system and a portable GPS unit.
mcb
Also, you don't get the same level of seamless integration between a single-screen G3X system and a portable GPS unit.
mcb
Hello Haydn,
Yes, the ENG page shows additional engine gauges not displayed at the top of a single display G3X including individual cylinder EGT and CHT readings.
Please refer to page 96 of the Rev. J G3X Pilot Guide for an example of how this will appear.
Thanks,
Steve
Hi Steve, yes I had previously looked through the manual but can not find reference to the engine page on a SINGLE screen setup, hence my question.
Can you display the detailed engine page on a single screen setup which would mean that you would loose the PFD information?
Haydn
Scott Hersha
Well Known Member
The 796 is a great back up and since you have XM, it's very useful. But you are backing up a VFR panel unless you have another gyro somewhere. That's why lots of people get two screens - IFR capability.
With a single screen G3X system, the instruments required by 14 CFR Part 91.205 are never hidden from view; they are always visible in the top half of the screen, as you can see on page 14 of the G3X Pilot's Guide. You use the bottom half of the screen as your multifunction display, which includes the detailed ENG page. Obviously it is reduced in size and all available information may require additional button pushing compared to a multi-screen system.
With a two-screen G3X system, the PFD unit can be configured to either be a full-time, full-screen display of flight instruments (and optionally also important engine instruments) or as a split-screen display which similar to the single-screen layout. The MFD unit in a two-display system displays full-screen versions of the map, waypoint information, charts, weather, engine information, etc.
A three-screen G3X system builds on this by adding a copilot's display, called PFD2, which can be configured in a variety of ways: full-time flight instruments, split-screen display, or a unique PFD2 layout which allows full-screen flight instruments to be swapped back and forth with full-screen MFD pages, including the detailed engine page.
And of course, if a display is removed or loses power, the remaining displays automatically adjust to compensate - a three display-system turns into a two-display system, and a two-display system turns into a single-screen system. As mentioned, the system is designed to be most useful and easy to operate with two or three displays, but a single-screen system is certainly usable in a space-constrained panel.
You can see images and read descriptions of the above on pages 14-17, 22-24, 51-52, 61, and 95-99 (among others) of the G3X Pilot's Guide. Let us know if you have additional questions.
thanks,
- Matt
Golf Echo
Active Member
Unless I'm mistaken, I don't think simply adding a second screen gets you IFR capability. Both screens would source their ADAHRS data from the same unit - the GSU 73 - so there is no redundancy of airspeed/attitude/etc.
Brantel
Well Known Member
Graham is correct in the case of the G3X system. Multiple screens are great but you still only get one ADAHRS. Some are happy with just the external autopilot as a backup but I chose to also add a Gemini PFD which serves as a complete self contained backup EFIS.
Thanks Matt, in that case can the second screen in a 2 screen setup be configured to display flight instruments? My reason for asking is to determine panel layout. If I can have two screens both capable of displaying flight instruments I will put one on each side of the panel, if only 1 instrument will display flight instruments, I will put both screens on the pilots side.
Thanks
In a two-display G3X system, the MFD unit can display flight instruments, but only if you ground a certain connector pin that forces it to be in "reversionary mode", which is the same split-screen view it would change to if the PFD unit went away. This would essentially give you a full-screen PFD and a split-screen MFD/PFD, which would probably be less than ideal. Typically we find that the ergonomics of a two-display system work best if the PFD and MFD are mounted as close together as possible, directly in front of the pilot. Obviously it's your panel so I won't tell you where to put the screens, but we know from experience and feedback that the "one on the left, one on the right" layout is not as nice as having both displays right in your primary field of vision. One thing you could do, if you really want a duplicate set of flight instruments for the copilot, would be to install a two-display system on the pilot's side of the panel and then provision for a future third display (PFD2) on the copilot side should you ever decide you want one.
- Matt
Backup Attitude
There are multiple topics being discussed here, so perhaps it is ok for Matt and I to tag team this one.
Whether you have 1, 2, or 6 ADAHRS units connected to your multiple display EFIS system, you still lack the independent, dissimilar attitude solution that most will recommend you have before launching into IFR conditions.
Having independent, dissimilar attitude solutions is important to prevent a common mode fault from being able to remove all sources of attitude.
Take a G1000 C182 or even a multi-engine G1000 Baron. Each of those aircraft only have a single source of attitude and air data connected to the displays, but like all G1000 aircraft, regardless of the number of displays or ADAHRS instruments, these aircraft have backup independent, dissimilar instruments to provide attitude, airspeed, and altitude to prevent a common mode fault in the EFIS from ever resulting in a condition where there is a total loss of these critical flight instruments.
Even airliners, on rare occasions, have been known to suffer a common mode fault where all of the primary flight displays are dark. Please don't fly IFR without at least a backup attitude instrument.
Thanks,
Steve
There are multiple topics being discussed here, so perhaps it is ok for Matt and I to tag team this one.
Whether you have 1, 2, or 6 ADAHRS units connected to your multiple display EFIS system, you still lack the independent, dissimilar attitude solution that most will recommend you have before launching into IFR conditions.
Having independent, dissimilar attitude solutions is important to prevent a common mode fault from being able to remove all sources of attitude.
Take a G1000 C182 or even a multi-engine G1000 Baron. Each of those aircraft only have a single source of attitude and air data connected to the displays, but like all G1000 aircraft, regardless of the number of displays or ADAHRS instruments, these aircraft have backup independent, dissimilar instruments to provide attitude, airspeed, and altitude to prevent a common mode fault in the EFIS from ever resulting in a condition where there is a total loss of these critical flight instruments.
Even airliners, on rare occasions, have been known to suffer a common mode fault where all of the primary flight displays are dark. Please don't fly IFR without at least a backup attitude instrument.
Thanks,
Steve
