Unwanted pitch up 6000 ft/min [Archive]

JWS

11-26-2007, 04:55 AM

Hi,

I'm using the latest Boeing MCP with CPFlight and encountered a strange problem. When trying to change altitude by using V/S, pressing V/S (after having entered the new altitude) always gives a 6000 ft/min pitch up (nasty when you want to descend). :x
Normally pressing the V/S button should give 00, and then you can dial in positive or negative values. I tried this with the CPFLight MCP alone and then things work out just fine. As soon as I use the PM software things go wrong.

Any ideas how to deal with this?

JWS

sas550

11-26-2007, 06:08 AM

Check your mcp.ini and look for this line:

AutoVS=On

Make sure it's set to on. That way You'll get a VS value that reflects your current vertical speed at the moment you press the button.

If it's already set to on I'm afraid I'm out of ideas at the moment. However, I'm sure there are others with ideas.

JWS

11-26-2007, 11:14 AM

Thanks Anders,

I'll try this. Have a new setup and had to reinstall the MCP software without the old ini settings at hand. Possibly I forgot this specific setting.

Will report the result.

JWS

PaulEMB

11-26-2007, 11:34 AM

JWS.
Iv'e also had this problem, but had been too busy too sort it out - my answer was to immediately transfer hand to V/S knob, and reduce V/S!

Not a fix, but it gets you back where you should be!

Tomlin

11-26-2007, 11:39 AM

David Rogers

11-26-2007, 12:38 PM

Hi Eric,

Depends on the Aircraft. On most 'heavy metal', turning the alt to a new value won't trigger any V/S, until a V/S (or more likely speed/pitch decent) setting is made too.

However, having flown in a Cessna 172 in real life that had an advanced Bendix Auto-pilot, that device would immediately set a climb or descent of 700 / -700 fpm, as soon as the alt was changed.

I'm not sure about the Lear, as we know FS applies a 'default' VS of 1800 / -1800 when the Alt value is changed buy my guess would be that in the real aircraft, no V/S would be set when the Alt is changed, until a pitch mode was also set. (V/S or IAS).

Hope this is what you meant - sorry if I got it wrong and just stated the obvious to you!

Tomlin

11-26-2007, 12:51 PM

Yes, that is what I was asking. I was aware of it being this way for the heavies, but wasnt sure about the LJ45. Guess I could go to my Pilot Operating Handbook? ! :-)

JWS

11-26-2007, 04:02 PM

Gentlemen,

Nice to have given you an opportunity to share other info with me and others, but the fact remains that I'm still stuck with the same problem now the solution Anders gave (AutoVS=On) doesn't help.

Funny thing is that I had the whole thing working properly on my old W98SE rig with FS2002. Couple of weeks ago changed to a new machine with XP Pro and FS2004, with the latest MCP 422 and now of a sudden I get this crap. As stated before, when I use the CPFlight MCP stand alone it works like it should. Together with PM I get this problem. Maybe it's the combo? I'll do some further testing and I'm open for suggestions.

Regards,

JWS

Trevor Hale

11-26-2007, 04:15 PM

Hi JWS.

I have noticed this issue and also another issue which I will go into a bit of detail following. The way I work around this issue you speak of is that prior to pressing the autopilot button I adjust my altitude and press the vs button, set the vs, and then press the A/P command button. I find this solves the issue as after the autopilot command mode is selected any further changes to altitude do not seem to create this large VS numeric.

The other issue I have is while the aircraft is on heading mode only no VS Mode, I get a porpus effect on the aircraft, like the autopilot wants to engage yet realizes it is not supposed to.

I personally feel that this issue is the new version of MCP, and urge you to try to locate an older version and see if that helps.

Best regards,

Trev

JWS

11-26-2007, 04:38 PM

Trev,

thought of that also and returned to version 420. The same lame result. I bless myself that I have saved all the previous versions on CD so I can go back to .... well some time ago.

Regards,

JWS

npbosch

11-27-2007, 04:14 PM

Try to set CorrectVSsign to on in FSUIPC.
Not sure if that solves your problem but it is worth a try.

JWS

11-28-2007, 05:41 AM

Norbert,

I'll give it a try but the CPFlight manual states that you have to uncheck this (if I'm not mistaken).

JWS

JonathanRichardson

12-03-2007, 03:04 AM

Hi

Check also that the CPFlight firmware is: 2.05. I will check this 6000ft V/S thing as well is not in the newer MCP build.

Regards
Jonathan Richardson

JWS

12-03-2007, 04:42 AM

Jonathan,

I've done some testing in relation to the problems I reported.
It turns out that the CPFlight stand alone works OK. After selecting the V/S I get 0000 and after that I can dial + or - to gain of loose altitude.

PM stand alone works OK as well. Changing ALt, pressing V/S, window shows 0000, then dial the desired vertical speed. Works like a charm

As soon as I combine the two, things go wrong. etc. Changing altitude by using V/S is only possible by hitting LVL CHG first and wait long enough to get stabilized. After that I press V/S and mostly it takes over the positive or negative value according to the LVL CHG. Using the V/S on its self is disastrous. When I push the V/S I always get a 6000 pitch up. When I press V/S again I (to get lower) I get a negative value but the aircraft doesn't respond to that. Pressing again leads to all kind of values + or -.

Run XP pro, latest PM (422) but went back to older versions with the same result, Firmware 2.05, FSUIPC, FS9.

Rgeards,
JWS

767300

12-10-2007, 03:56 AM

Okay, not to hijack, but here's a question for those 'in the know'.

When you change ALT on the autopilot and either increase or decrease its value, should the VS be 0000 FMP or some user-chosen value somewhere between 0000 and 1800 FPM?

I know where to change this in the aircraft file, just wondering what most transport aircraft should be in this regard.

Hi,

In relation to the 767300, when V/S is engaged the window opens AT the current vertical speed. The danger with the v/s on the 763 is that you can fly through the altitude in the MCP altitude window. One to watch just in case you think its like VNAV or FLCH. You could bust your altitude very quickly or look out the window and wonder why the houses are gettn bigger!

James

phil.

12-10-2007, 12:11 PM

hi,
i have the problem that when always engaging VNAV the plane climbs direct with 6000 feet per minute, this is not real. is here a solution for ?
Phil.

JonathanRichardson

12-11-2007, 05:40 AM

JWS

01-20-2008, 03:17 PM

Hi

It sounds like a read back problem then from the hardware, we would have to look into that in combination with the CPFlight MCP. I will also check this with the new MCP build.

Regards
Jonathan Richardson

Jonathan,

any news on this issue? Using LVL CHG doesn't work with landings so I sure could use a proper functioning V/S (please).

Best regards,

JWS

JonathanRichardson

01-22-2008, 07:52 PM

>any news on this issue? Using LVL CHG doesn't work with landings so I sure could use a proper functioning V/S (please).

Hi

Unfortunately I do not see any problem with V/S at all here. It could be an ini setting that is different. My only thought is that perhaps AutoV/S ini setting is off in the simulator - but I still have to cross check that. I made a note to observe the V/S selection in the last sim session and I saw no errors. It was operating exactly like it should (never saw 6000ft/min!!). I also have a vague memory that errors like this can be down to either the panel.cfg file or the aircraft.cfg file settings. But this is just vague - it is a long time since I saw or had to deal with V/S errors. We also run CPFLight MCP with latest firmware in the sim. I will keep an eye out for this though, and also check the ini settings re the auto setting.

Regards
Jonathan Richardson

JonathanRichardson

01-22-2008, 08:15 PM

>i have the problem that when always engaging VNAV the plane climbs direct with 6000 feet per minute, this is not real. is here a solution for ?
Phil.[/QUOTE]

Did you follow correct procedures? What was the GW indicated in the CDU prior to take-off? And did this match the G/W computation of your airfile? Did you check that? And the type.txt entry Netweight? Which build of the CDU are you using? It is possible with a light aeroplane to get 6000ft per min climb at low altitude and max thrust. Perhaps the actual weight of your flight model differs from the CDU type txt weight? Please check it is *very* important. It could also be your general procedures / ops are incorrect, a/c load (G/W?), and perhaps even maybe a bad flight model, or the climb thrust tables are wrong...? It can be many things, maybe all is correct, you just took-off with a very light aeroplane !

I tested some VNAV procedures a few days ago, the default VNAV speeds computed by the CDU were set to 250kts for the SID which I did not accept, so I input slower speeds for the early part of the SID prior to departure, after take-off, and when I selected VNAV, it flew the profile in the climb correctly. I saw no 6000ft per min climbs....

Regards
Jonathan Richardson

JWS

01-24-2008, 03:52 AM

My only thought is that perhaps AutoV/S ini setting is off in the simulator - but I still have to cross check that. I made a note to observe the V/S selection in the last sim session and I saw no errors. It was operating exactly like it should (never saw 6000ft/min!!). I also have a vague memory that errors like this can be down to either the panel.cfg file or the aircraft.cfg file settings.
I will keep an eye out for this though, and also check the ini settings re the auto setting.

Regards
Jonathan Richardson

Jonathan,

I will check auto V/S ini setting (which should be "on"??). As far as I can tell it's the combo CPFlight and MP MCP that gives the problem. CPFlight stand alone or PM MCP stand alone do seem to function properly (engaging V/S gives 0000 in the window, then set + or - using thumbwheel).

Tell me what specific information you need from my settings etc. and I will mail them to your Project Magenta mail address. Thanks for the efforts so far.

Regards,

JWS

JonathanRichardson

01-24-2008, 04:49 AM

>I will check auto V/S ini setting (which should be "on"??). As far as I can tell it's the combo CPFlight and MP MCP that gives the problem. CPFlight stand alone or PM MCP stand alone do seem to function properly (engaging V/S gives 0000 in the window, then set + or - using thumbwheel).

Hi

We use that combination with latest firmware. I have a very slight feeling from memory that the Auto V/S is off, but I have not checked - I'm working in other areas right now, but if I fire up the 737 today I will check it. I presume you have checked both alternatives already, so it is unlikely to be this setting (I presume).

Regards
Jonathan Richardson

NicD

01-24-2008, 07:22 AM

I have the same combination and have had better results with the Auto-V/S turned off.

JWS

01-24-2008, 11:42 AM

I'll double check both settings once again.

JWS

JWS

01-25-2008, 04:34 AM

Tried AutoV/S 'on' and 'off' but with the same result.:-( Engaging V/S means +6000 ft in the window, no matter what you do (re-installed latest firmware).

However, I noticed that for a very brief moment a negative value seems to appear in the window before 6000 becomes visible. It's a flash, too short to see what the actual value is, but I managed to see the minus sign before it turns to +6000.
I wonder if PM settings like speed intervention and altitude intervention are responsible. E.g. speed intervention doesn't function properly on the CPFlight in my case. During VNAV (speed window empty) pressing the CPFlight MCP SPD button longer than a second or so should result in an open SPD window (so you can adjust the speed) while maintaining the VNAV mode. In my case VNAV always closes and SPD mode is engaged.

So I'll check this out, maybe tonight.

I tested with default aircraft (737 & 747). Results are the same, PM alone works fine (including SPD Int), CPFlight MCP alone also, the combination of the two doesn't.

Regards,

JWS

JWS

03-22-2008, 06:25 AM

Problem solved thanks to CPFlight & PM.

JWS

marco

04-15-2008, 10:41 AM

Hello JWS,

You say : problem solved. May we have some more informations ?
Thx in advance.

Marco ;)

JWS

04-15-2008, 01:32 PM

Marco,

I've made on the request of CPFlight some serial log files during test flights engaging V/S etc. These files have been studied by Paolo and Jonathan to see what was happening between the MP MCP software and the CPFlight hardware. Paolo discovered some anomalies (what exactly I don't know) and made some alterations to the firmware and now the CPF "rocks the planet" again. There some minor other issues yet but I'm in the process of making new log files and will hand them over to CPF. And this is really the way to do it because the guys at PM and CPF can make sense out of them files.

Grtz.

JWS