Master Caution: Hydraulics

[ryanbatc 12,833]

It seems I'm getting a master caution and low pressure on both hydraulic systems. I don't have failures enabled and I've never gotten this message before. I'm having a tough time finding out what's really going on. Looking at the FCTM under section 8.23, it discusses hydraulics but only for landing...

 

These manuals aren't very FSX friendly... they're more or less a direct copy of the real ones (which is great!) but I've got no idea what section or manual I should be reading to decipher this low pressure light.

 

Can someone guide me to the correct manual?

 

[Sara Louise Capon 21]

In the real manuals,

Quick Reference Handbook (13.1)

Flight Crew Operations Manual (13.2)

[Spin737 102]

Wasn't that problem an issue with early versions of NGX? Or something about panel saves?

[G-CIVA 62]

PMDG NGX QRH - Go to the Alphabetical Index starting on pp13 ....

 

Then .....

 

NNC 13 (13.TOC.1) (pp 285) onwards)

 

Do you have service based failures or any malfunctions enabled? would be my next port of call.

[MrPlaneDriver 41]

Anytime you face a failure or an alert in the cockpit, the first book you want to grab is the Quick Reference Handbook (QRH). It'll tell you what to do in such situations, giving you immediate solutions for any abnormality that may arise. The other books (FCOM and FCTM) are not aimed at solving problems or dealing with abnormal situations. They are manuals, and as such their job is to explain how the systems work and how should the flight crew execute procedures.

[ryanbatc 12,833]

Thanks...

 

Page 1175 (on the pdf) of FCOM part 2 says this:

 

"If a leak develops in the electric motor–driven pump or its related lines, or components common to both the engine and electric motor–driven pumps, the quantity in the reservoir steadily decreases to zero and all system pressure is lost."

 

So is this saying that while departing KLAS a leak occurred in hydraulic system A and B's electric pump? How do I fix this? Or is this a "land as soon as practical" caution? Also from reading this section it seems either system can power the plane with no loss of control etc etc. But in my case BOTH elec pump's have developed a leak... BTW, nothing happened... I continued my flight with the warning lights on the overhead (lol). When I landed they turned off.

 

In the QRH all it shows is what to do... nothing tells me WHY this happened.

 

p.s. I've got no "service based failures" or "malfunctions" enabled.

[Spin737 102]

Yeah, this is a bug. Do you have the latest SP?

[VIPERGTSR01 22]

I don't think there is any leak. They're overheated, have you been playing around with them switching them on and off? That is the common way to overheat them (even without any failures settings on)

 

 

Did you go to the failures section of the CDU and check what active failure you have?

[ryanbatc 12,833]

I don't think there is any leak. They're overheated, have you been playing around with them switching them on and off? That is the common way to overheat them (even without any failures settings on)

 

Did you go to the failures section of the CDU and check what active failure you have?

 

No I didn't touch them the entire flight. Also I'll have to note the part about checking the CDU as I've left the flight already.

 

Yeah, this is a bug. Do you have the latest SP?

 

Yes SP2C right?

[MrPlaneDriver 41]

Yes SP2C right?

 

It's the SP1C. SP2 is coming out after the 777 release. But if it's "C", you've got the latest service pack.

[cdt996 3]

The electric hydraulic pumps are cooled by fuel through a fuel-hydraulic heat exchanger. Did the fuel in each main tank drop below 1675 lbs at any point while the electric hydraulic pumps were on? You also mention KLAS. Could the fuel temp gotten excessively high while on the ramp?

 

Also, did you use a custom saved panel state for this flight? If so, that is a potential cause of this issue.

 

 

[davierosoft 13]

Yes, it is a problem solved many updates ago.

For FSX check:

-If you have old ngx version and then updates it, make sure you have followed instructions to delete old pane states/saves. This is true for pre-sp1 versions.

If you have updated from a sp1 version to the 1c it is not necessary to delete files.

If you have downloaded the latest one (new customer):

Your problem is about fuel.

Fuel quantity in WING TANKS must be at least 760Kgs each or the hyd will heat up.

Fuel temperature must be checked.

It could be also a wheater program error wich gives you an higher temperature inflight, but, unless you're flying in the flames, your fuel must cool the hydraulics.

 

It is not a failure, so it is something that cannot be disabled, it is an user error (probably) by running the pumps in the wrong conditions.

What about hyd quantity?

[ryanbatc 12,833]

The electric hydraulic pumps are cooled by fuel through a fuel-hydraulic heat exchanger. Did the fuel in each main tank drop below 1675 lbs at any point while the electric hydraulic pumps were on? You also mention KLAS. Could the fuel temp gotten excessively high while on the ramp?

 

Also, did you use a custom saved panel state for this flight? If so, that is a potential cause of this issue.

 

I set 50% fuel in the FMS... perhaps this was a factor?

[Fabo 213]

Should not be. Most likely just a freak occurence, or a bug with particular panel save. Just start your next flight from one of the original panel states and all should be fine.

[ryanbatc 12,833]

Yeah this seems to be the case Fabo. I flew another almost identical flight with no problems. I do have another issue but I'll make a new thread.

 

Thank you everyone for your input very interesting.