Avidyne Homepage
Forum Home Forum Home > Avidyne General > IFD 5 Series & IFD 4 Series Touch Screen GPS/NAV/COM
  New Posts New Posts RSS Feed - Cross-sync off greatly improves usability
  FAQ FAQ  Forum Search   Register Register  Login Login

Cross-sync off greatly improves usability

 Post Reply Post Reply
Author
Message
clydeps View Drop Down
Groupie
Groupie
Avatar

Joined: 05 Sep 2015
Location: Australia
Status: Offline
Points: 72
Post Options Post Options   Thanks (0) Thanks(0)   Quote clydeps Quote  Post ReplyReply Direct Link To This Post Topic: Cross-sync off greatly improves usability
    Posted: 20 Jul 2016 at 12:25am
When my IFDs were installed in my Cirrus, they were initially set up with cross-sync on. I flew with that for a while, but found the inability to have different flight plans or waypoints in the two units to be frustrating at times. So recently I turned that off, in the process losing the keyboard convenience mode and some other features, but gaining a great deal of extra functionality. I've just completed a big cross-country trip, flying into big and small airfields, and thought I'd report my impressions.

The EXP5000 PFD allows me to select either IFD as the NAV source, as well as having a selection for a bearing pointer and an AUX block that gives bearing and distance to a waypoint. These features were essentially unusable with cross-sync turned on since the two IFDs were always tracking to the same waypoint so unless there was a useful VOR, I could not select different information with those buttons. With cross-sync off, the IFDs operate as two completely independent navigators and allow me to enter different flight plans or direct-to waypoints. I've so far used this for various things:

1) Flying to a destination where I'm either not yet cleared for an approach, or haven't decided if I will need to fly an approach, I can select and activate the approach on the #2 so I get two sets of data (ETE, VSR, TOD) for the two different scenarios. Loading but not activating an approach on the active IFD has the drawback of giving misleading information especially for VSR, since it assumes flying to the destination then back out to start the approach. When I get cleared for the approach I can simply toggle the PFD to the #2 as NAV source.

2) Similarly after commencing an approach if one IFD is still on direct-to the destination I can have the bearing pointer on the PFD giving me direction and distance, useful for position broadcasts.

3) I sometimes need to fly an approach to an airport that is not my actual destination, just to get down through the clouds then track visually to my actual destination a few miles away. I can program the two units appropriately so I have the bearing pointer tracking my actual destination while flying the approach.

4) Using the #2 IFD to try "what-if" scenarios - e.g. if I have a fuel stop planned, what if I skipped that and went straight to my final destination - what's the distance, time and fuel required?

Not being able to copy flight plans from one unit to the other is a nuisance, but the loss of the keyboard convenience hasn't bothered me much - I use a Bluetooth keyboard for the #1 anyway. Some alerts get acked on both with cross-sync on, but I didn't notice this as an issue.

Speaking of alerts, one thing that really bugs me is the "FLTA inhibited" CAS message after takeoff. The last thing I need as I'm climbing out is the system requiring me to ack a message that just says the system is doing exactly what it's supposed to do! I have FLTA turned off on #2, and it also gives me a message, which has to be separately acked (but at least doesn't flash on the PFD.) That particular alert is not helped with cross-sync btw.

One other feature I used for the first time this trip was the rubber-banding to add waypoints. This worked a treat when I needed to follow the coastline rather than flying over a big expanse of water. There were no suitable waypoints in the database, but the rubber-band feature worked perfectly.

I look forward to the time when the software supports cross-sync on without automatically mirroring all flight plan changes between the two units, but in the meantime I'm leaving it turned off. The extra functionality is well worth the minor drawbacks.

Clyde

Back to Top
JBSmitty View Drop Down
Newbie
Newbie
Avatar

Joined: 20 Jul 2016
Location: KPGD
Status: Offline
Points: 12
Post Options Post Options   Thanks (0) Thanks(0)   Quote JBSmitty Quote  Post ReplyReply Direct Link To This Post Posted: 20 Jul 2016 at 12:37pm

Thanks for your thoughts, Clyde.

I'll add one more reason to do it although I am still in my teething stages with a 540/440 combo. 

What I don't like is that I can't split the output to my Garmin VOR Head (GI-106).  Namely, if I'm on a GPS approach (say LPV) I can't send the ILS/LOC information from #2 Navcom to it.  Removes a nice back up.  This was easy to do with the Garmins even when crossfilled.  Am I perhaps missing something?

Jim Smith, SR22
Back to Top
Gring View Drop Down
Senior Member
Senior Member


Joined: 30 Dec 2011
Location: Kingston, NY
Status: Offline
Points: 726
Post Options Post Options   Thanks (0) Thanks(0)   Quote Gring Quote  Post ReplyReply Direct Link To This Post Posted: 20 Jul 2016 at 12:43pm
Jim, I'm not sure if I'm understanding you, but if you have 2 IFDs, you can have one in GPS mode with an indicator and the other in VLOC with an indicator to do exactly what you are suggesting.

Edited by Gring - 20 Jul 2016 at 12:44pm
Back to Top
JBSmitty View Drop Down
Newbie
Newbie
Avatar

Joined: 20 Jul 2016
Location: KPGD
Status: Offline
Points: 12
Post Options Post Options   Thanks (0) Thanks(0)   Quote JBSmitty Quote  Post ReplyReply Direct Link To This Post Posted: 20 Jul 2016 at 12:58pm

That's exactly what I'm asking, thanks! 

I have a single Aspen set up with the 540/440.  When I press the OBS on #2, it changes it on #1 as well. Is there something simple I am missing? 

The GI-106 does not have a source selector like the Aspen, maybe that's something the shop missed?

Jim Smith, SR22
Back to Top
Gring View Drop Down
Senior Member
Senior Member


Joined: 30 Dec 2011
Location: Kingston, NY
Status: Offline
Points: 726
Post Options Post Options   Thanks (0) Thanks(0)   Quote Gring Quote  Post ReplyReply Direct Link To This Post Posted: 20 Jul 2016 at 1:21pm
When crossfill is on, OBS syncs across the two.  However, GPS and VLOC can be different between the two.  So, you can have your ASPEN HSI showing a RNAV approach, and your second GI106 showing an ILS to the same runway.  
Back to Top
JBSmitty View Drop Down
Newbie
Newbie
Avatar

Joined: 20 Jul 2016
Location: KPGD
Status: Offline
Points: 12
Post Options Post Options   Thanks (0) Thanks(0)   Quote JBSmitty Quote  Post ReplyReply Direct Link To This Post Posted: 20 Jul 2016 at 1:41pm
Got it, thanks!
Jim Smith, SR22
Back to Top
TangoCharlie View Drop Down
Newbie
Newbie
Avatar

Joined: 31 May 2016
Location: KISP
Status: Offline
Points: 17
Post Options Post Options   Thanks (0) Thanks(0)   Quote TangoCharlie Quote  Post ReplyReply Direct Link To This Post Posted: 20 Jul 2016 at 2:32pm
I agree with Clyde: compared with other aircraft I fly, I miss having independent operation of the two FMSs.  We had two IFD540s installed in our plane about 6 months ago, and I was waiting to write comments until I had become familiar with the operation of the boxes and their design philosphy.

One design element that I recall seeing posted here on the forums (though I can't find the post now) is that in a two-unit installation, the two are supposed to operate as a single FMS.  After flying for a while with these, I still can't understand this design point as it removes significant functionality that I use in a two-FMS setup.  Some quick examples are examining alternate flight plans and evaluating alternate descent profiles (I've been told to cross X at Y, but my experience tells me I'll ultimately be given something else later).

On other aircraft I have flown with more traditional FMS layouts where two FMSs are installed, I can operate them in either a synced or independent mode.  In synced mode, it operates much as the two IFD540s operate now.  In independent mode, they work as separate #1/#2 FMSs, and I can manually transfer flight plans to the cross-side unit, I can couple the autopilot to either FMS, and so forth.  It is a pretty well-esablished mode of operation, and the Garmin units accomplish this by enabling or disbling auto crossfill as mentioned.

I fail to understand why when cross-sync is disabled, we don't have the ability to cross-fill flight plan information between the units as Garmin, Collins, Honeywell, etc. support.  If fully decoupling the boxes is important, perhaps there could be three modes: one where cross-sync is fully turned off, one independent operation mode where one manually initiates any cross-side transfers, and one sync mode where the two share the same plan and changes from one side are propagated to the other.

I know this has been asked for before, but it would be  great if this functionality would be available in a new software release.  It must be possible to certify this, as most of the other systems I'm familiar with operate like this.

A side effect of this in our installation would be the reduction in confusion on "global" CAS messages.   We want to display one source of weather (GDL69A) and traffic (TAS600) on one box, and another source of weather and traffic (FIS-B) on another.  But when we get failure messages from any system, they are "global" and show up everywhere, and I have no idea which unit is reporting a failure.  What is needed for a "global" message (shown on all boxes) would be an additional indication of which unit is failing (e.g. Datalink #1 Receiver Fault).

--Mark M
Back to Top
AviJake View Drop Down
Admin Group
Admin Group


Joined: 26 Mar 2009
Location: Lincoln MA
Status: Offline
Points: 2815
Post Options Post Options   Thanks (0) Thanks(0)   Quote AviJake Quote  Post ReplyReply Direct Link To This Post Posted: 22 Jul 2016 at 2:59pm
Interesting perspective.  I don't share it but then again, the scenarios you use that for are not how I fly.

To address what I think are the open questions/requests in this thread:

1.  We have no plans at this time to provide CrossSync'ing flexibility.  So, at least for the foreseeable future, you either turn it on or turn it off.  It's bi-directional when on and you can't selectively pick/choose what data you do/don't want to share.

2.  Some of the CAS annoyances are being addressed in Release 10.2.   FLTA Inhibited CAS messages go away with 10.2.    Global behaviors are being tweaked slightly.  BTW, in the ALERTS tab, you can see the long message text which tells you exactly what device is squawking.

Did I miss anything? 
Steve Jacobson
sjacobson@avidyne.com
Back to Top
clydeps View Drop Down
Groupie
Groupie
Avatar

Joined: 05 Sep 2015
Location: Australia
Status: Offline
Points: 72
Post Options Post Options   Thanks (0) Thanks(0)   Quote clydeps Quote  Post ReplyReply Direct Link To This Post Posted: 23 Jul 2016 at 2:29am
Originally posted by AviJake AviJake wrote:

Interesting perspective.  I don't share it but then again, the scenarios you use that for are not how I fly.
...
We have no plans at this time to provide CrossSync'ing flexibility
Steve, the way IFR is conducted here in Australia is a little different to the US. There is a lot of uncontrolled airspace here vs. almost none in the lower 48, which means that pilots have both a lot more options on how to conduct a flight. A lot of the time I'm telling ATC what I'm about to do, rather than them telling me what to do. With that in mind, can you explain why there are no plans to implement any kind of customisation of cross-sync functionality? I presume there is some philosophical basis to that decision. If there is not, can it at least be added to the wish-list?

Clyde

Back to Top
NZFlyer View Drop Down
Newbie
Newbie


Joined: 27 Jun 2014
Location: New Zealand
Status: Offline
Points: 26
Post Options Post Options   Thanks (0) Thanks(0)   Quote NZFlyer Quote  Post ReplyReply Direct Link To This Post Posted: 23 Jul 2016 at 4:35am
I use my IFD540 and IFD440 independently for the flexibility reasons that others have mentioned.
In independent operation I would like to see Cross-Fill and Keyboard Convenience. Why is this not available Steve?


Edited by NZFlyer - 23 Jul 2016 at 4:39am
Back to Top
AviJake View Drop Down
Admin Group
Admin Group


Joined: 26 Mar 2009
Location: Lincoln MA
Status: Offline
Points: 2815
Post Options Post Options   Thanks (0) Thanks(0)   Quote AviJake Quote  Post ReplyReply Direct Link To This Post Posted: 23 Jul 2016 at 8:47am
We do have it in the candidate future feature database.   It's a lot more work to do it than one might think and it flies in the face of the basic dual IFD philosophy.  For those two reasons, we have not attempted to tackle it yet.

It comes up at every new release initial inclusion meeting we have and so far, has not made the cut.    The difficulty lies predominantly in the FMS logic code and how it uses shared data in many, many, many locations in the code and providing the type of flexibility you are asking for will be a non-trivial undertaking to say the least.
Steve Jacobson
sjacobson@avidyne.com
Back to Top
NZFlyer View Drop Down
Newbie
Newbie


Joined: 27 Jun 2014
Location: New Zealand
Status: Offline
Points: 26
Post Options Post Options   Thanks (0) Thanks(0)   Quote NZFlyer Quote  Post ReplyReply Direct Link To This Post Posted: 23 Jul 2016 at 2:32pm
Thanks for the explanation Steve. I hope the features make the cut one day.
Back to Top
TangoCharlie View Drop Down
Newbie
Newbie
Avatar

Joined: 31 May 2016
Location: KISP
Status: Offline
Points: 17
Post Options Post Options   Thanks (0) Thanks(0)   Quote TangoCharlie Quote  Post ReplyReply Direct Link To This Post Posted: 05 Aug 2016 at 2:09pm
Originally posted by AviJake AviJake wrote:


...

2.  Some of the CAS annoyances are being addressed in Release 10.2.   FLTA Inhibited CAS messages go away with 10.2.    Global behaviors are being tweaked slightly.  BTW, in the ALERTS tab, you can see the long message text which tells you exactly what device is squawking.

Did I miss anything? 


I had a chance to check out the detail of what is shown in the ALERTS tab, and at least for our installation on 10.1.2, the explanatory text says only "Traffic sensor has failed."  This is on unit #1 for a failure of the traffic device connected to #2.  The device connected to unit #1 (TAS600) was operating.  It might be good for it to state somehow exactly which device (even if it only said #1 or #2).

--Mark M
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.107 seconds.