VNAV descent aircraft won't hold - Overspeeding...

[raam123]

Hi,

 

Is it included on the SP1 fixes ? Aircraft won't hold VNAV descnet.... overspeeding all time.

Thx.

 

[Matty260191]

looks steep

[scoobflight]

See the list and the notation on the FDE -

Also, your report needs details:

Which plane(s)? 170/175/190/195?  Just one it does this? All? Some?

Flightplan? Also details on the altitude plan/constraints. Where in the flightplan, between which waypoint (s) does this happen?  Was this after the flight computer computed POD or between two waypoints on decent? Did the waypoints have speed and/or crossing restrictions? (As noted by @Matty260191 the decent path looks to be programmed steep.)

Aircraft weight?

Can the issue be repeated?  Exactly how is it repeated?

A P3D FLT file saved just prior to where the issue can be duplicated.  (Attach the file to your post with the details).

 

[raam123]

16 hours ago, Matty260191 said:

looks steep

Thats what the aircraft profile builds using VNAV... so what do you mean by saying steep ?

(I didn't  change speed or constrains during descent...)

If it is not implanted in the upcoming SP1 I will upload whatever is needed.

 

[Matty260191]

in the descent setup i find the defaults are to fast for the aircraft to handle. i use 260/.70/2 or 2.5

[scoobflight]

7 hours ago, raam123 said:

If it is not implanted in the upcoming SP1 I will upload whatever is needed.

In order to provide nany assistance your report needs details:

Which plane(s)? 170/175/190/195?  Just one it does this? All? Some?

Flightplan? Also details on the altitude plan/constraints. Where in the flightplan, between which waypoint (s) does this happen?  Was this after the flight computer computed POD or between two waypoints on decent? Did the waypoints have speed and/or crossing restrictions?

Aircraft weight?

Can the issue be repeated?  Exactly how is it repeated? (Being reproducible is needed in order to find a solution.)

A P3D FLT file saved just prior to where the issue can be duplicated.  (Attach the file to your post with the details).

[raam123]

1 hour ago, scoobflight said:

In order to provide nany assistance your report needs details:

Which plane(s)? 170/175/190/195?  Just one it does this? All? Some?

Flightplan? Also details on the altitude plan/constraints. Where in the flightplan, between which waypoint (s) does this happen?  Was this after the flight computer computed POD or between two waypoints on decent? Did the waypoints have speed and/or crossing restrictions?

Aircraft weight?

Can the issue be repeated?  Exactly how is it repeated? (Being reproducible is needed in order to find a solution.)

A P3D FLT file saved just prior to where the issue can be duplicated.  (Attach the file to your post with the details).

E195, Weight at descent 43,000Kgs

I didn’t change speeds for the descent as Matty:

in the descent setup i find the defaults are to fast for the aircraft to handle. i use 260/.70/2 or 2.5

But I think it should handle higher then that.

Thanks.

[scoobflight]

@raam123 :

So just 195?  No flights in the other planes?

Flightplan? Also details on the altitude plan/constraints. Where in the flightplan, between which waypoint (s) does this happen?  Was this after the flight computer computed POD or between two waypoints on decent? Did the waypoints have speed and/or crossing restrictions?

Can the issue be repeated?  Exactly how is it repeated? (Being reproducible is needed in order to find a solution.)

A P3D FLT file saved just prior to where the issue can be duplicated.  (Attach the file to your post with the details).

Again, without the above with a situation that can be duplicated the issue cannot be investigated.

[raam123]

1 hour ago, scoobflight said:

@raam123 :

So just 195?  No flights in the other planes?

Flightplan? Also details on the altitude plan/constraints. Where in the flightplan, between which waypoint (s) does this happen?  Was this after the flight computer computed POD or between two waypoints on decent? Did the waypoints have speed and/or crossing restrictions?

Can the issue be repeated?  Exactly how is it repeated? (Being reproducible is needed in order to find a solution.)

A P3D FLT file saved just prior to where the issue can be duplicated.  (Attach the file to your post with the details).

Again, without the above with a situation that can be duplicated the issue cannot be investigated.

All my flights are streamed so full movie is here.

I had to use FLCH and speedbrakes to maitain speed... VNAV didnt hold.

I also tried to lower descent speed in FMC , didn't work as well ... speed runs away slowly and steady from target VNAV speed.

Also you can see landing pitch with flaps 5 which is very high in my opinion as a real world pilot.

I never flew the Embraer... ( I understand pilots of EMB says it is standart, but still.... feels very odd...)

[scoobflight]

49 minutes ago, raam123 said:

All my flights are streamed so full movie is here.

You need to provide the information as I have repeatedly noted in a text format along with the requested FLT file.  Video entertaining for some to watch but doesn't provide needed information for programmers to test and reproduce the issue you are reporting so the issue cannot be confirmed nor repeated etc.

 

53 minutes ago, raam123 said:

Also you can see

And as stated prior see the list and notation on the FDE -

[Matty260191]

just to chime in the descent is not managed well by the FMC/AP i experience this every flight. i fine the A/T wont Idle quick enough sometimes to keep speed down. I overcome this like i said by adjusting the descent profile to 260/M.70/2. hopefully whatever FDE tweaks you done to stop the [fast] climb rate will also help this.

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Edit mods: adjusted tone of post to but not content