PMDG737 NGXu Center Fuel Tank pumps

[hvw 419]

Hi Bryan,

In FS2Crew v4.1 I ran into a small issue. While using SOP2/Buttons the FO switches off the center fuel tank pumps right after I did switch them to on.  This only happens the first time that I switch those pumps on. This didn't happen in previous FS2Crew versions. I may have overseen a setting, but so far I wasn't able to find out which one. Do you have any idea how I can prevent my FO from putting his fingers on the center fuel pump switches?

Thanks,
Hans

[byork 2,260]

Nothing recently changed in the fuel pump logic department.

If the FO shuts them off, he probably did it for a reason.  The fuel pumps should be off when the fuel is below a certain level.

 

[hvw 419]

15 minutes ago, byork said:

The fuel pumps should be off when the fuel is below a certain level.

Yes, I know. But the FO does so after take-off and passing FL100 when I turn them on. He, stubborn as he is, turns them off. I turn them on again and then he keeps quiet 🙂 I just wonder why this happens. This doesn't happen in P3Dv4.5 and FS2Crew v4.1. Funny, don't you think?

[byork 2,260]

As mentioned nothing changed in the fuel pump logic.

Does the FO announce "fuel pumps on"... he should turn them back on at 10K if they were off during takeoff if the center fuel tank quantity is greater than 1000 pounds.

 

[hvw 419]

Just now, byork said:

Does the FO announce "fuel pumps on"

No, he does not. I will dive further into this and will keep you posted on what I may find.

[hvw 419]

Unfortunately I didn't find the cause nor the resolution to this. Any ideas on how to resolve this are welcome

[byork 2,260]

Does the FO say thing?

Also double check the PMDG options... maybe they added some fuel management logic that I haven't heard about.

Cheers,

 

[hvw 419]

4 hours ago, byork said:

Does the FO say thing?

Also double check the PMDG options... maybe they added some fuel management logic that I haven't heard about.

Cheers,

He just say that he switched off the center pumps after he switched them off. I then turn them on again and they remain on for the remainder of the flight. Very weird. Yes, I checked PMDG's options but none of them have anything to do with fuel management. 

I keep on investigating. It's strange that in P3Dv4.5 and the latest 737 NGXu all goes wel, and that in the P3Dv5 versions this "undocumented feature" is acting up.

Best,

Hans

[hvw 419]

Bryan,

Can it be that by adding the Cabin Release Altitude: 10K, 18K, Cruise or Off option also the check on center fuel pump status was accidentally modified to, say, FL180? I will check later today what happens when I switch the center fuel pumps to on at passing FL180 rather than my usual FL100. (Yes, the center tanks are not empty 🙂 )

Best,
Hans

[byork 2,260]

It would have made no difference.

Make a video of it so I can see it.

Cheers,

 

[hvw 419]

Bryan,

I sent a link to the video in a private message to you.

 

Hans

[byork 2,260]

Thanks, I saw it and replied.

Cheers,

 

[byork 2,260]

So others can see:

If the fuel low pressure lights (left and right) illuminate, it will trigger the fuel pumps off action. In the video, it appears both those lights illuminate.

When you're manually turning on those fuel pumps, both lights illuminated and you hit the trigger for fuel pumps off.

Why you never experienced this before?  Maybe PMDG updated the pump light logic.

 

[hvw 419]

After the FO switched the pumps off again I immediately turned them to on again (the 2nd time after passing FL100) , the lights of course illuminated for a little while again and now the FO didn't act upon this action. SO why did he do so in the first occasion and not in the 2nd? Would it be possible to include a 5-10 seconds pause into the coding as to prevent the FO from turning the pumps off again in those cases where he shouldn't?

Perhaps the FS2Crew trigger to immediately switch off the pumps in this situation, passing FL100 switching center pumps to on again, is too sensitive.

 

Best,
Hans

[byork 2,260]

It didn't happen the 2nd time because that function wasn't reset.

You confused the system because you manually turned on the pumps.

Send me a support ticket.... I'll send you a custom version.

Cheers,