Can´t open any Maindeck Cargo Door

[GermanSpottingTV 4]

Hello!

 

First of all, I have to say that the 747 v3 is a very nice addon! I like it so much!

But I have a problem. I can´t open the cargo doors in the maindeck (side cargo and nose door).

In every plane. (F, ERF, BCF, M). The other doors working right!

I hope you can help me.

 

Best regards,

Robin Plate

[CaptKornDog 281]

Is your External Power 2 or APU Gen 2 AVAIL? (Not ON.)

 

From the manual's introduction:

 

"When using a cargo variant, the nose and side cargo doors require that a power source be available, but not in use. As an example, if you are using APU power, GEN1 can be used for power, but GEN2 will need to be switched off (left AVAIL) in order for the doors to operate."

[GermanSpottingTV 4]

Thank you for your answer! That was the solution, sorry for my mistake.

 

Best regards,

Robin Plate

[VS0 23]

Is your External Power 2 or APU Gen 2 AVAIL? (Not ON.)

From the manual's introduction:

"When using a cargo variant, the nose and side cargo doors require that a power source be available, but not in use. As an example, if you are using APU power, GEN1 can be used for power, but GEN2 will need to be switched off (left AVAIL) in order for the doors to operate."

Just out of interest do you or anyone else here know the reasoning behind this?

[Guest]

Just out of interest do you or anyone else here know the reasoning behind this?

 

From a quick scan it looks like it's a failsafe to preclude accidental electrically triggered Opening/ Closing whilst in use by ground personnel.

[scandinavian13 5,192]

Shameless plug for the Intro Manual. I know that will probably get tiring to see for all of these things, but we spent a good bit of time coming up with the main things that will trip you up. Have a read through them. I guarantee it'll give you a quicker response than posting here and waiting (moreover, it'll also prepare you with the correct expectations of how things work instead of being frustrated that they're "not working" or "not working correctly").

[vegasjon 39]

Yup! Most of these questions I've see answered in the documentation...

[StevenHPerry 20]

From a quick scan it looks like it's a failsafe to preclude accidental electrically triggered Opening/ Closing whilst in use by ground personnel.

 

Or while in flight for that matter, which is the explanation I got from an authoritative source.

[VS0 23]

Or while in flight for that matter, which is the explanation I got from an authoritative source.

Maybe I'm being a bit slow but this is the bit I don't really understand. "As an example, if you are using APU power, GEN1 can be used for power, but GEN2 will need to be switched off (left AVAIL) in order for the doors to operate."

 

I don't own the product so cannot read the FCOM myself.

[scandinavian13 5,192]

Rich,

 

When you have the APU running, you have two APU GENs to use: L and R. Most of the time, you would select both L and R to get the most power available to the plane. In order to move the doors, though, you need to de-select one of the GENs such that it only shows as AVAIL (available, but not in use).

[Guest]

Or while in flight for that matter, which is the explanation I got from an authoritative source.

 

 

In flight - it's no longer an issue as you're no longer connected to Ground Power or APU. It has to do with variable voltage vagaries (fluctuating voltages) of GPU's/ APU's and (over) sensitive sensors on the cargo door mechanisms, etc.

[PerWel 23]

Many subjects here are what we called RTFM cases when I did techsupport back in the -90th. Read The F¤&/%ng Manual

[downscc 1,327]

Just out of interest do you or anyone else here know the reasoning behind this?

My theory is that the SSB bus tie contact is open under these conditions; thus, the two AC buses are no longer synchronized (voltages could be out of phase). The motors will operate from either bus, but if it were both then there would be a problem if the power were not synchronized.  At least it makes sense to this engineer.  No other guess I've seen makes much sense so I'm sticking to this theory.

[Guest]

Many subjects here are what we called RTFM cases when I did techsupport back in the -90th. Read The F¤&/%ng Manual

 

Thanks for that valuable observation.

 

Aaanyway...it is basically to do with voltage fluctuations across the buses and ensuring an inadvertent close of doors does not happen while crew are in the way loading and unloading, etc.

 

For us - in Sim World - it's a procedure we have to conform with - just like real world - and PMDG have modelled it - like the sticklers for detail they are. Bless them.

[VS0 23]

Many subjects here are what we called RTFM cases when I did techsupport back in the -90th. Read The F¤&/%ng Manual

I don't own the product yet and am therefore not going to read the FCOM yet but thanks for the information from the rest of you. I fly Airbus real world and was merely interested in the logic behind the systems as they have their own little quirks like most aircraft. Thanks again.

My theory is that the SSB bus tie contact is open under these conditions; thus, the two AC buses are no longer synchronized (voltages could be out of phase). The motors will operate from either bus, but if it were both then there would be a problem if the power were not synchronized.  At least it makes sense to this engineer.  No other guess I've seen makes much sense so I'm sticking to this theory.

And actually this is where I was getting confused, from the way I interpreted the information the door power was coming from the GEN which was Avail and not in use however would I be right in thinking it's actually the opposite and Boeing are trying to achieve a single power source or generator for all systems including the doors in order to allevaiate unsynchronised buses, voltages etc. therefore using the single GEN that is switched to ON and thus ignoring the second GEN not being utilised?