VNAV issues.

[NicD]

After doing dozens of flights on Worldflight recently I was able to observe others using the sim and watch for trends. The VNAV, speed and takeoff issues mentioned here were all present consistently and a pain in the butt. It was embarassing actually - even though it was out of my control..

The last thing a crew needs is to be not trusting the MCP just after the plane has rotated. And its ok for crews to get MCP mode confusion, it's NOT ok for the software itself to get mode confusion!

It was also embarassing to have to brief crews to "switch the HDG SEL" before they made any major changes in the CDU (level, speed, star etc). C'mon PM... get embarassed with me please.. then fix it huh? It's not good promotion for you guys.

[David Rogers]

Hi Dave,

This last thing you mentioned regarding the speed issue, I change all the time. I have no issues setting speeds in the CLB/CRZ/Des Pages, it always changes that on the MCP.

You should check this, because I know I do not have this issue you mention.

Trev

Hey Trev,

I am using the CDU with the Engravity hardware CDU - I wonder if the problem lies in the interface between these? I should add that this particular issue only happens intermittantly.... I think it is if the aircraft slightly shoots the cruise altitude while climbing (sometimes caused by excessive thrust in the climb, causing too high a rate of climb). If I smooth out the climb using V/S, near the crz altitude I can usually avoid this one.

Dave.

[David Rogers]

It was also embarassing to have to brief crews to "switch the HDG SEL" before they made any major changes in the CDU (level, speed, star etc). C'mon PM... get embarassed with me please.. then fix it huh? It's not good promotion for you guys.

Nic - I'm really pleased you mentioned this one - I can't believe I missed it from my 'moan list' ....... any changes made to waypoints in the CDU, leads to the plane making uncommanded turns away from the LNAV course.... it's as if the plane is turning to fly back home!!

ie... tonight;

- Had a very short flight plan; EGNT > POL > TNT > CUMRI > EGGD.

- En route, I added CDF in between CUMRI and EGGD, executed, and altough the plane was supposed to be on a direct course to TNT (and still was after my modification), it turned around 180 degrees, uncommanded while in LNAV.

So as Nic said, you need to select HDG SEL first to ensure you are still flying in your intended direction after making any CDU LEGS changes!

Definately not good enough PM (do they ever read this?).... the CDU currently falls way short of my excpectations for paying £574 ($1140) dollars for this software.

[NicD]

David... have you passed on your findings to PM support (email)? I think they're aware of many of these issues but it may help if more users provide thorough feedback (such as yours) directly to PM as well.

cheers

[Bob Reed]

Nic - I'm really pleased you mentioned this one - I can't believe I missed it from my 'moan list' ....... any changes made to waypoints in the CDU, leads to the plane making uncommanded turns away from the LNAV course.... it's as if the plane is turning to fly back home!!

ie... tonight;

- Had a very short flight plan; EGNT > POL > TNT > CUMRI > EGGD.

- En route, I added CDF in between CUMRI and EGGD, executed, and altough the plane was supposed to be on a direct course to TNT (and still was after my modification), it turned around 180 degrees, uncommanded while in LNAV.

So as Nic said, you need to select HDG SEL first to ensure you are still flying in your intended direction after making any CDU LEGS changes!

Definately not good enough PM (do they ever read this?).... the CDU currently falls way short of my excpectations for paying £574 ($1140) dollars for this software.

To answer 1 of your questions.. No PM does not read this. And some of the other problems you report where not there until about the last 8 months.. So at one point the software was much more stable... Yes we are all waiting for an update to fix these!!

[Trevor Hale]

Hey Trev,

I am using the CDU with the Engravity hardware CDU - I wonder if the problem lies in the interface between these? I should add that this particular issue only happens intermittantly.... I think it is if the aircraft slightly shoots the cruise altitude while climbing (sometimes caused by excessive thrust in the climb, causing too high a rate of climb). If I smooth out the climb using V/S, near the crz altitude I can usually avoid this one.

Dave.

I am not using an Engravity CDU, but what I can tell you is through out world flight, when I was instructed to increase or decrease speeds by ATC, I altered it in the CRZ Page, and saw an immediate change on the MCP. Each and every time commanding Higher or lower N1%. However, Keep in mind after you input the new speeds you need to follow them up with a couple presses of the enter key.

Possibly the light is not lighting on the enter key to show that they are required, however it is in fact required.

Trev

[dnoize]

Hey Trev,

I am using the CDU with the Engravity hardware CDU - I wonder if the problem lies in the interface between these?

The CDU only acts as a "dumb" terminal. i.e. it only displays what PM is telling it to and sends back keypresses.
In no way it influences PM logics/vnav/cdu behaviour, nor does it contain any logics itself.

Stef

[David Rogers]

Thanks all.

Nic - Yes I talked (via email) to Jonathan about the loss of waypoints problem(s). What I found strange is that he acted as though it was the fist time he was hearing about the issue (when I know for a fact it is a known issue).

The last correspondence was from me, asking him when these bugs would be addressed in a new build ............. never got a reply from thereon.

Trev - Hear what you're saying about the button presses and have needed to press enter a couple of times but doesn't affect this 'shooting the altitude' problem and the subsequent VNAV confusion. I think this particular one is down to some settings in the aircraft files around the aircraft weight being too light, which causes too high a climb rate (on a speed referenced climb), which then causes the 'shoot' !

Stef - Absolutely agree. It's clear from the types of issues that the core of the problem is the PM software. The hardware CDU is fab in every way and I'm delighted with it

Just need to keep pestering PM and Enrico / Jonathan for a new build to address these (serious) CDU problems. (and some MCP bugs too). I like to have ultimate faith in my Flight Director but often find I need to ignore it, when currently using PM - that is not why I invested into the software.

[pdpo]

Hi all,

Up until may of this year I send Enrico almost on a weekly bases emails containing a looonngg
problem list with bugs in the airbus software. Reading this post I notice the same kind of problems with the boeing software. Some problems I had got solved in previous build, but new
problems kept appearing. At some point in time I have given up ....
Last week I send enrico another email asking how he was doing and if there was still being
worked on the software for us hobbyists, non-professional customers.
His reaction was that he was still working on it and did not let us down but that new builds would be less frequent (more time in between). As a reply on that I send him again a list with the most annoying bugs but no reply....until now....

I just know that if we would do the same in our company we would be very fast out of the market which we address...

Greetz Peter

[David Rogers]

Well one suspected bug to strike off the list is this VNAV CRZ Speed issue. As I suspected, the problem turned out to be a symptom of incorrect settings in the 737700 aircraft file. (I realised that the aircraft files that I was supplied with when I bought PM were not the most recent, which is strange in itself....). I downloaded the corrected aircraft files and the aircraft is now climbing at a more realistic rate.... and more importantly VNAV PATH (ie...speeds) is working great now, as the aircraft no longer 'busts' through the cruise altitude, which is what was upsetting the VNAV phases . Thanks to all who helped on that one (especially my buddy Trev ).

However, the bug list I am going to send Enrico this evening is :-

1. En-route waypoints lost whenever an arrival or departure is selected in DEP/ARR page. (very serious - almost a show stopper when flying on-line ).
2. TO/GA (vertical) does not revert to FLCH during climbout.
3. Initial LNAV capture on climbout does not behave realistically, when LNAV is armed on the ground.
4. Random heading changes in LNAV, where waypoints are modified. (very serious).
5. FL CH defaults to a speed of 150 when engaged at low altitude - should be the current speed.
6. T/D pseudo waypoint is occasionally not positioned on ND at the point where descent commences (and where PMsounds announces "descent". (the latter descent point seems correct).
7. VOR frequencies entered Manually into NAV/COM/XPDR page are replaced by auto-tuned settings. Where a frequency is hard entered into the CDU, and a 'M' is annunciated next to the freq, this setting should not be erased 2 mins later by a different autotuned setting!

These are the consistant bugs that I am getting and so am confident to report to PM....

If anyone else wants to add any that they're pretty confident about, we could send through a 'complete' list to PM... ?



**PS. When I indicate 'very serious' above, it's just highlighting what I believe to be the unacceptable bugs. It doesn't mean a loss of personal perspective as in : ........as 'very serious' as a triple heart bypass .....