Wrong ETA (Trip Planning page) (resolved)

[Figadas 20]

Hello everybody,

I just recently purchased the GTN 650/750 units (merci for the sale, Jean-Luc) but I've been a real world user of the 430/530 for many years now.

I've been having a small issue getting wrong ETAs on the Trip Planning page. I have time set on UTC, the times is correct, I get proper ETE for points and cumulative (destination), I get right ETA on the RAIM prediction page but I always get wrong (hour) ETA on the Trip Planning page, like if it was a time zone issue.

I never had this problem with the 430/530 (I still use it on the same aircraft) but since I don't have real world experience with the 650/750 I decided to come here looking for help, maybe I'm doing something wrong or it is suppose to be like that and I'm just missing something.

Have anyone had similar problem.

 

thank you in advance. stay safe.

regards,

Igor

[fppilot 4,350]

7 hours ago, Figadas said:

Hello everybody,

I just recently purchased the GTN 650/750 units (merci for the sale, Jean-Luc) but I've been a real world user of the 430/530 for many years now.

I've been having a small issue getting wrong ETAs on the Trip Planning page. I have time set on UTC, the times is correct, I get proper ETE for points and cumulative (destination), I get right ETA on the RAIM prediction page but I always get wrong (hour) ETA on the Trip Planning page, like if it was a time zone issue.

I never had this problem with the 430/530 (I still use it on the same aircraft) but since I don't have real world experience with the 650/750 I decided to come here looking for help, maybe I'm doing something wrong or it is suppose to be like that and I'm just missing something.

Have anyone had similar problem.

 

thank you in advance. stay safe.

regards,

Igor

Were you at a point just after entering the flight plan, or were you in the air on your way?  You might also mention which simulator and its version.

Here is a screen shot of my RXP GTN 750 from a flight today. I reloaded an autosave file created by FSUIPC.   It is spot on for my destination and consistent with the ETA's for the interim waypoints.  I have my GTN System Settings to 24 hour format and a 5:00 offset.  For Zulu time an offset of 0:00 should be used.  In either case, the ETA for my interim fixes are consistent with my ETA for my destination. I was in the air between my departure airport and the first fix in my flight plan when I scrolled the flight plan to show the destination.

 

Edited July 1, 2020 by fppilot

[Figadas 20]

14 hours ago, fppilot said:

Were you at a point just after entering the flight plan, or were you in the air on your way?  You might also mention which simulator and its version.

Here is a screen shot of my RXP GTN 750 from a flight today. I reloaded an autosave file created by FSUIPC.   It is spot on for my destination and consistent with the ETA's for the interim waypoints.  I have my GTN System Settings to 24 hour format and a 5:00 offset.  For Zulu time an offset of 0:00 should be used.  In either case, the ETA for my interim fixes are consistent with my ETA for my destination. I was in the air between my departure airport and the first fix in my flight plan when I scrolled the flight plan to show the destination.

 

Hello, Mr. Patton thank you so much for your reply.

It happens in the air on the trip planning page (Utilities). I'm running P3Dv4.5 HF2, system is set to UTC, ETA shows up correctly on the RAIM prediction page when I select to check availability on destination, in that page the ETA is correct, so I don't think it is a time zone issue. What I haven't done yet but I will on my next flight is to set one of the field on the map screen to show ETA and see if the information is correct over there. I also haven't tried the flight plan screen (the one on your picture) but I will check that one also. Is there any other page that would show ETA so I can crosscheck the information? I also haven't tried LCL time but to be honest I rather have to calculate myself the ETA in Zulu than use LCL time.

Another detail is that I do also use the saved flight feature (SimStarter NG), but always from parked position, cold and dark, and before I start avionics I sync to real time with FSReal Time. THe times on the timer page (GTN) match the real time in Zulu when I startup the unit and I have no issues at all doing the same process with the 430/530 v2.

I'm going to run some tests and take some screenshots if necessary.

Thank you again!

Edited July 2, 2020 by Figadas
SimStarter NG info added

[fppilot 4,350]

Due to some quirks with my now 5 year old system I am still flying with FSX.  New system planned for time when I migrate to FS2020.  I again reloaded my flight from yesterday at an enroute point of FSUIPC autosave and my trip planning page and functions look fine. Since you are starting from a saved flight, have you tried updating the date and time directly into P3D instead of with FSReal Time?  Perhaps it is not interfacing correctly with HF2.

[Figadas 20]

3 minutes ago, fppilot said:

Due to some quirks with my now 5 year old system I am still flying with FSX.  New system planned for time when I migrate to FS2020.  I again reloaded my flight from yesterday at an enroute point of FSUIPC autosave and my trip planning page and functions look fine. Since you are starting from a saved flight, have you tried updating the date and time directly into P3D instead of with FSReal Time?  Perhaps it is not interfacing correctly with HF2.

Hi again Mr. Patton,

That's the screen where I have issues! I just loaded "as we speak" my last flight in europe, I loaded everything like I always do and going to run some tests, check different pages where ETA is displayed, check changing to LCL time etc. IF it doesn't work I'm going to load without SimStarter NG and manually set everything, location, cold and start, time through P3D etc and I will let you know. 

Thank you so much once again.

my best regards,

Igor

[Figadas 20]

1 hour ago, Figadas said:

Hi again Mr. Patton,

That's the screen where I have issues! I just loaded "as we speak" my last flight in europe, I loaded everything like I always do and going to run some tests, check different pages where ETA is displayed, check changing to LCL time etc. IF it doesn't work I'm going to load without SimStarter NG and manually set everything, location, cold and start, time through P3D etc and I will let you know. 

Thank you so much once again.

my best regards,

Igor

Ok, so I have more questions than answers now after fiddling with it. The ETA is lagging, so the longer you fly the less accurate it gets. I took come screenshots and I still have the flight running as I type here and went to check and to my surprise the ETA now is behind the actual current time, even though the ETE is still showing proper and accurate time.

Tried reloading the FP, closed FSReal Time (which I don't have set to Auto update, only to set the real time once I load everything) and loaded time and date on P3D itself, tried everything, including switching to LCL but the error still persists.

Here are just some screenshots, sorry didn't want to flood the post with screenshots from every different setting and page

Just to reiterate, the ETA works on the map screen if you set the field to show ETA, and it's working on the FP page, the only page you get incorrect values is on the Utilities->Trip Planning page, and like I mentioned before it's way more perceptible further in the flight then just after departure.

 

 

 

This is really not a big deal, specially since the correct info get be gathered on different pages but I, most of all, wanted to make sure it's not me mishandling the equipment and the features.

thank you

regards,

Igor

 

EDIT: I'm 144nm from my destination, it is 1338Z and the ETE is showing 00:21 which is correct and ETA on Trip Planning page is 1300Z which is obviously incorrect unless I'm flying the concorde and going back in time  😉 

Edited July 2, 2020 by Figadas

[fppilot 4,350]

Looks like you tried to include images but they are not showing.  I just completed a 2 hour flight in FSX and paid a lot of attention to that page.  Had no issues.  What if anything are you doing with the Departure Time field on that page?

[Figadas 20]

54 minutes ago, fppilot said:

Looks like you tried to include images but they are not showing.  I just completed a 2 hour flight in FSX and paid a lot of attention to that page.  Had no issues.  What if anything are you doing with the Departure Time field on that page?

I can't seem to find a way to upload or link hosted images, using the option "insert image from URL" on my previous post didn't work, even though I can see the screenshots in my previous post.

Anyway this is the best I can do for now, I'm sorry about that.

https://imgur.com/a/Q011oQq

 

 

 

regards,

Igor

Edited July 2, 2020 by Figadas

[RXP 2,336]

Hi,

You're using 'Sensor Data', but have you enabled Sensor data input to the GTN, like the Shadin Air Data input?

Does it make any difference if you deactivate "Use Sensor Data"?

It could be a bug in the Garmin trainer itself too, or even a bug in the Garmin GTN code you'd find in a real GTN.

About the later: one of our astute customer did find a discrepancy in turn direction/angle indication in the GTN. After lengthily flight tests and debugging we've concluded it must be a bug in the GTN. Once he has been able to try out in a real GTN, the same bug was there too. This is troubling because this bug affects the very security of flying with a GTN and went unnoticed for so long by real GTN pilots.

Back to topic, we, the simmer community, are using our fancy devices in ways deeper than most are using in real life and we get the chance sometimes to find genuine bugs affecting the real units!

In this case, it might still be a RXP induced bug though.

[Figadas 20]

1 hour ago, RXP said:

Hi,

You're using 'Sensor Data', but have you enabled Sensor data input to the GTN, like the Shadin Air Data input?

Does it make any difference if you deactivate "Use Sensor Data"?

It could be a bug in the Garmin trainer itself too, or even a bug in the Garmin GTN code you'd find in a real GTN.

About the later: one of our astute customer did find a discrepancy in turn direction/angle indication in the GTN. After lengthily flight tests and debugging we've concluded it must be a bug in the GTN. Once he has been able to try out in a real GTN, the same bug was there too. This is troubling because this bug affects the very security of flying with a GTN and went unnoticed for so long by real GTN pilots.

Back to topic, we, the simmer community, are using our fancy devices in ways deeper than most are using in real life and we get the chance sometimes to find genuine bugs affecting the real units!

In this case, it might still be a RXP induced bug though.

Hi Jean-Luc, thanks for your comment.

Yes, I just double checked and  I do have "Shadin Air Data Computer" enabled in the settings. It doesn't make any difference if I deactivate on the unit (haven't tried deactivating in the settings and the unit at the same time, yet)

I unfortunately might not be able to do any more tests today but I will do for sure tomorrow. If I can't get any satisfactory results I'm going to run just the trainer, outside P3D environment and see what happens.

Thanks again and I'll post back here as soon as I have a chance to test it.

regards,

Igor

 

Edited July 2, 2020 by Figadas
Checked settings "Shadin Air Data Computer"

[RXP 2,336]

Ok let us know, but please do try disabling Shadin Air Data computer because if there is any RXP influence in this issue, this would be the one setting affecting it most likely.

[Figadas 20]

15 hours ago, RXP said:

Ok let us know, but please do try disabling Shadin Air Data computer because if there is any RXP influence in this issue, this would be the one setting affecting it most likely.

Good morning Jean-Luc, 

So, just in the middle of my test flight, which is the exact same flight I've been testing this issue, and unfortunately disabling Shadin Air Data in the settings and disabling Sensor Data on Utilities -> Trip Planning haven't solved the problem. Sorry, I wish I had better news. I tried different modes of calculation, tried on Point to Point mode, Flight Plan mode, from P.Pos. calculated by the GPS and also from Waypoint right as I was overflying the particular point. 

The times are way more accurate at the beginning of the flight, but as an example, right now I'm 20 minutes in my flight (roughly) and the ETA is already 20 minutes OFF (showing a much earlier arrival time). Bear in mind that even with the Shadin and Sensor off the ETA on FP and also Map pages are correct.

Thank you Jean-Luc, please let me know if there's anything else you would like me to do in regards or settings or any other way to help out.

Enjoy your weekend.

Regards,

Igor

 

EDIT: Hi Jean-Luc, so after reading the GTN750  manual (section 15-13) I found the difference between the modes and maybe an explanation for what's going on. So, form what I understand, if you have Point to Point selected with an active flight plan, the GPS is going to calculate ETA based on ETE over the Time of Departure not current time (if you are already enroute) which is what's happening, that's why the further down you go enroute the greater the deviation from the real ETA, but if you have an active flight plan and you select the flight plan mode, than the unit is suppose to give you and ETA based on ETE and the current Time, so you would get a precise ETA for the destination updated in real time, but the unit is not doing that, it is treating, no matter what mode you select as in Point-to-Point, so always calculating ETA based on your departure time. I believe it's safe to say that if this end up being the issue, it's something coming form Garmin's Trainer and no from your product, Jean-Luc. Please just remind that I have no experience or received any training with the actual unit so this could be just me not using the features correctly, it would be great to hear from pilots that actually own/operate the unit.

EDIT2: I can confirm Garmin's Trainer behaves exactly the same, you have to manually change the Depart. Time to the current time whenever you want to check the ETA. Oh well, at least we get current information no the other pages so not a big deal. Thank you Jean-Luc and Frank for your help. Sorry for wasting everybody's time

 

Edited July 3, 2020 by Figadas

[fppilot 4,350]

On 7/2/2020 at 1:10 PM, fppilot said:

What if anything are you doing with the Departure Time field on that page?

 

6 hours ago, Figadas said:

I can confirm Garmin's Trainer behaves exactly the same, you have to manually change the Depart. Time to the current time whenever you want to check the ETA.

I figured it had something to do with the handling of Departure Time. 

I cannot recall right now when or how it happens, but there are some executions within the GTN that when you change them the GTN resets the Departure Time to the time you executed that action. 

Also, the Departure Time resets to the current time if you restore a flight from an FSUIPC autosave backup file.  At least in FSX it happens.

[RXP 2,336]

18 minutes ago, fppilot said:

Departure Time resets to the current time if you restore a flight from an FSUIPC autosave backup file. 

This is normal: the trainer is starting anew and the last known timers (inside the trainer) are not saved in the autosave backup file when you exited the previous session. When you reload the session, the GTN boots up and resets the timers as expected when booting up.

This would be a cool addition and we certainly can alter these values inside the trainer but it could also have side-effects in the way the trainer works afterward. Ultimately the best would be a trainer process state save/restore feature and this might be doable to some extent but this is the kind of feature which is inherently error prone and system sensitive (in other words support ache)

[RXP 2,336]

7 hours ago, Figadas said:

but the unit is not doing that, it is treating, no matter what mode you select as in Point-to-Point, so always calculating ETA based on your departure time. I believe it's safe to say that if this end up being the issue, it's something coming form Garmin's Trainer and no from your product, Jean-Luc.

Thank you for your enduring patience with this and for the additional insight which will certainly be useful to other customers.

My first reaction to your findings is that this sounds like a bug in the GTN code in general (including the real device), not a feature of the trainer in particular.

Edited July 3, 2020 by RXP