Boeing VNAV Behaviour and FP import

[Charalampos Perivolas]

1. If we have a flight plan from one airport to the other , without an
intermediate point, then there is a strange behaviour in VNAV calculation from
the program.
The plane after take off , with LNAV VNAV mode engaged keeps the speed that
is calculated for the FAF of the destination airport (190 Knots)regardless
of our Final FL and the calculated speed in our CRZ CDU Page (340/.790)
IMHO the correct behaviour should be to accelerate to 250 Knots under FL100
and after passing that FL, to continue accelerating to our Climb speed
programmed in our CLB CDU page.
2. If we aproach an Airport at Final FL and we pass the final waypoint before
FAF, then when the TOD is reached the plane slows down to the calculated
speed for that FAF point (190 Knots), regardless of the FL that is flying,
and the calculated speed in the DES CDU page.
IMHO it should start the descent with the calculated speed through DES CDU
page managing the speed automaticaly all the way down up to that FAF point.
3. If we import a FS2k4 Flight plan in the CDU (pressing two times RTE and
5RSK), then the two first letters of every waypoint are missing (ATV is
showing as V , BADEL is showing as DEL, and if it is a two letter NDB it is not
shown at all, only a blank line).
I do not use this feature since I want to manualy enter my routes every time,
but since I saw it I thought it is good for you to know it for an
upcomming fix.

Blue Skies!

Babis

[Enrico Schiratti]

Blue skies to you too, and I think I know what that is
caused by... will check it out.

How far apart are those airports?

Ciao

Enrico

"Charalampos Perivolas" wrote in message
news:381836.76659@wb.onvix.com...
> 1. If we have a flight plan from one airport to the other
> , without an
> intermediate point, then there is a strange behaviour in
> VNAV calculation from
> the program.
> The plane after take off , with LNAV VNAV mode engaged
> keeps the speed that
> is calculated for the FAF of the destination airport (190
> Knots)regardless
> of our Final FL and the calculated speed in our CRZ CDU
> Page (340/.790)
> IMHO the correct behaviour should be to accelerate to 250
> Knots under FL100
> and after passing that FL, to continue accelerating to our
> Climb speed
> programmed in our CLB CDU page.
> 2. If we aproach an Airport at Final FL and we pass the
> final waypoint before
> FAF, then when the TOD is reached the plane slows down to
> the calculated
> speed for that FAF point (190 Knots), regardless of the FL
> that is flying,
> and the calculated speed in the DES CDU page.
> IMHO it should start the descent with the calculated speed
> through DES CDU
> page managing the speed automaticaly all the way down up
> to that FAF point.
> 3. If we import a FS2k4 Flight plan in the CDU (pressing
> two times RTE and
> 5RSK), then the two first letters of every waypoint are
> missing (ATV is
> showing as V , BADEL is showing as DEL, and if it is a two
> letter NDB it is not
> shown at all, only a blank line).
> I do not use this feature since I want to manualy enter my
> routes every time,
> but since I saw it I thought it is good for you to know it
> for an
> upcomming fix.
>
> Blue Skies!
>
> Babis
>
>

[Charalampos Perivolas]

Hi,

The distance was 210nm, but I checked it also with a distance af 100nm and
there is the same prob.

Blue Skies

Babis

[Tom Stian Bjerk]

To the question #1.
I also have the same problem. There is someting strange there.. Its not
acting the same way as with the CDU from 737NG-PMDG..

I tough mabye I did some wrong with the programing of the CDU.

Best Regards
Tom Stian Bjerk


"Charalampos Perivolas" wrote in message
news:381836.76659@wb.onvix.com...
> 1. If we have a flight plan from one airport to the other , without an
> intermediate point, then there is a strange behaviour in VNAV calculation

> from
> the program.
> The plane after take off , with LNAV VNAV mode engaged keeps the speed
> that
> is calculated for the FAF of the destination airport (190
Knots)regardless
> of our Final FL and the calculated speed in our CRZ CDU Page (340/.790)
> IMHO the correct behaviour should be to accelerate to 250 Knots under
> FL100
> and after passing that FL, to continue accelerating to our Climb speed
> programmed in our CLB CDU page.
> 2. If we aproach an Airport at Final FL and we pass the final waypoint
> before
> FAF, then when the TOD is reached the plane slows down to the calculated
> speed for that FAF point (190 Knots), regardless of the FL that is
flying,
> and the calculated speed in the DES CDU page.
> IMHO it should start the descent with the calculated speed through DES
CDU
> page managing the speed automaticaly all the way down up to that FAF
> point.
> 3. If we import a FS2k4 Flight plan in the CDU (pressing two times RTE
and
> 5RSK), then the two first letters of every waypoint are missing (ATV is
> showing as V , BADEL is showing as DEL, and if it is a two letter NDB it
> is not
> shown at all, only a blank line).
> I do not use this feature since I want to manualy enter my routes every
> time,
> but since I saw it I thought it is good for you to know it for an
> upcomming fix.
>
> Blue Skies!
>
> Babis
>
>