Solved nav : ETA different on HUD & on DED

[suhkoi69]

Is it normal that there is a small discrepancie regarding ETA on NAV mode : indeed, I noticed there is a difference between ETA from HUD & DED
(see screenshot below)

[MaxWaldorf]

Should be fixed in next release

[Dee-Jay]

@suhkoi69 said in nav : ETA different on HUD & on DED:

Is it normal that there is a small discrepancie regarding ETA on NAV mode : indeed, I noticed there is a difference between ETA from HUD & DED
(see screenshot below)

I am not sure about the following, but …
Are you sure you have no SPI deltas?

I do not remember (must check in -34) but I wonder is DED page guves the ETA on steerpoint, and HUD ETA on SPI. If no delta SPI they should be the same but it could be possible to have very slight discrepancies (such as on take in acount elevation while the other doesn’t (?))

[ewildcat]

@Dee-Jay
I get the same discrepancy with no delta in 4.36U1 as well.

[Dee-Jay]

@ewildcat said in nav : ETA different on HUD & on DED:

@Dee-Jay
I get the same discrepancy with no delta in 4.36U1 as well.

I suggest to try to play with steerpoint elevation and see to distance/ETA is modified …

[SLangner]

It seems to me that the DED shows the planned TOS, whereas the HUD shows and updated time based on the actual GS.

[LorikEolmin]

@SLangner said in nav : ETA different on HUD & on DED:

It seems to me that the DED shows the planned TOS, whereas the HUD shows and updated time based on the actual GS.

Read all the lines of the DED?

[mirv]

We will check the code. There could be some minor discrepancies in how each is calculated… thanks for pointing it out. It wouldn’t be the first time when two pieces of code that should be doing the same thing aren’t…

[Dee-Jay]

@SLangner said

It seems to me that the DED shows the planned TOS, whereas the HUD shows and updated time based on the actual GS.

Both are displayed on DED.

[Dee-Jay]

@mirv said in nav : ETA different on HUD & on DED:

We will check the code. There could be some minor discrepancies in how each is calculated… thanks for pointing it out. It wouldn’t be the first time when two pieces of code that should be doing the same thing aren’t…

Could be a matter of wind or wind angle calculations. I remember MavJp having some works on FPM, ground speed or stuff when he had fixed how the wind was taken in accout … etc … Suggest to check with him in case of doubts.

[mirv]

@Dee-Jay

It dawned on me. I wonder if the HUD avionics sampling code is the cause…it applies to airspeed/Alt/heading but I’ll have to check if it’s being applied to the time windows as well…

[Dee-Jay]

@mirv said in nav : ETA different on HUD & on DED:

@Dee-Jay

It dawned on me. I wonder if the HUD avionics sampling code is the cause…it applies to airspeed/Alt/heading but I’ll have to check if it’s being applied to the time windows as well…

Could be interesting to check of the issue was already present on 4.34/4.35 …

sorry if my text is unreasonable, this website doesn’t work well on my smart phone, can’t read what I am typing…

[MaxWaldorf]

Should be fixed in next release