Taking action against failures?

[AirbusCG 52]

On two of my recent 8 flights in the 777 I had an engine shutdown due to the rise of the oil temprature beyond the limits.

This always happened when reducing engine thrust at the start of the descend.

The oil qty goes down to about 5-6 and this causes the oil temp to rise.

As soon as I notice this I bring the thrust lever of the affected engine to the mid position to allow better cooling of the oil, however this has no effect at all.

According to my source 15 is the minimum oil quantity for dispatch, however this also happens with oil quantities up to 18.
Unfortunatly I can't find any hard data on the minimum oil quantity in the FCOMs or FCTM.

I get similar impressions when handling other failures such as generator disconnects, etc.
I take the corrective action as advised in the QRH, but it never has an effect.

Thus my question if it is possible to fight a failure or if failures are "definite" and can't be corrected (unless by turning it off in the FMC menu of course)?

Ps.: If it's not possible to take action against a failure at the moment, might I suggest it as a feature for the upcoming 747 v2? That'd be great!

[scandinavian13 5,192]

 

 

Thus my question if it is possible to fight a failure or if failures are "definite" and can't be corrected (unless by turning it off in the FMC menu of course)?
Ps.: If it's not possible to take action against a failure at the moment, might I suggest it as a feature for the upcoming 747 v2? That'd be great!

 

Sounds less like a failure and a corrupted panel state causing things to get weird. Try loading from a different panel state and see how it reacts.

[AirbusCG 52]

I've tried a different panelstate, but the same happened.

The problem is since the 777 doesn't save the used oil if you load the default panelstate one has to save the panelstate after each flight and then reload it on the next flight (or just set it as default state) if you want the "wear" of the aircraft simulated properly.

Perhaps also an idea for the 747v2?

 

Could you tell me what the minimum oil quantity for dispatch is? As said, I've found 15 in my sources, but that seems to be wrong judging by the way the 777 reacts to it.

[downscc 1,327]

 

 

if you want the "wear" of the aircraft simulated properly.

 

That not exactly correct.  Not sure about fluid levels but aircraft "wear" (time in use) is independent of panels. Each tail number has it's own file containing run times.  This is elaborated in the Introduction document.

[Jet Tech 31]

There doesn't seem to be a hard limit for Minimum oil other than to ensure that the LO indication is not displayed next to the Quantity on the 200LR.  That being said,  the Maintenance procedures for operating the aircraft in ETOPS operations requires a minimum of 21 Qts for dispatch.  It sounds from what your describing that you aren't servicing the system frequently enough.

[AirbusCG 52]

That not exactly correct.  Not sure about fluid levels but aircraft "wear" (time in use) is independent of panels. Each tail number has it's own file containing run times.  This is elaborated in the Introduction document.

 

True on the maintenance status of the systems, the fluids are indeed part of the panelstate though, so if you do not save your panelstate after each flight you'll always start with them completly full.

 

There doesn't seem to be a hard limit for Minimum oil other than to ensure that the LO indication is not displayed next to the Quantity on the 200LR.  That being said,  the Maintenance procedures for operating the aircraft in ETOPS operations requires a minimum of 21 Qts for dispatch.  It sounds from what your describing that you aren't servicing the system frequently enough.

 

mmh, the LO indication is displayed from 6 down if I'm not mistaken, however as the oil quantity lowers quite much when you pull the thrust levers back when initiating the descend and this is what triggers the failure.

 

Thus my question, is the LO indication also valid for dispatch?

There surely must be a value somewhere in some document that outlines how much oil you need, is there not?

Perhaps a real world 777 pilot knows?

 

At this moment my systems have 22 hours left for maintenance, so that's not the issue. After the next trip she'll end up in the hangar for a D check though!

[rondon9898 84]

Minimum quantity as far as I know is 18 quarts for dispatch and I'm certain it's in the FCOM limitations section but don't have a copy on me at the mo

[downscc 1,327]

Minimum quantity as far as I know is 18 quarts for dispatch and I'm certain it's in the FCOM limitations section but don't have a copy on me at the mo

Don't think FCOM has this, limitations only address minimum oil temperatures required for take off.  I think this is a company dispatch item.

[Jet Tech 31]

Emanuel,

 

My point was that we service the aircraft to 21qts prior to every ETOPS departure which for our 777 fleet is every flight so dispatching with 15 qts would be extremely unusual for that aircraft.  The minimum dispatch oil as Dan pointed out is an Airline specific SOP for each fleet.  I would recommend more frequent servicing to avoid the issue in the future as the "Scheduled" servicing is more an "A" check level servicing and not daily servicing that occurs like Oils and Hydraulics.

[AirbusCG 52]

Emanuel,

 

My point was that we service the aircraft to 21qts prior to every ETOPS departure which for our 777 fleet is every flight so dispatching with 15 qts would be extremely unusual for that aircraft.  The minimum dispatch oil as Dan pointed out is an Airline specific SOP for each fleet.  I would recommend more frequent servicing to avoid the issue in the future as the "Scheduled" servicing is more an "A" check level servicing and not daily servicing that occurs like Oils and Hydraulics.

 

I see, so you indeed have to refill oil after each and every flight ending at your homebase? wow, I wouldn't have thought that it's so maintenance intensive!

Oh well, if that's how the 777 is like in real life then why not. In the end I don't pay the oil

 

I get similar impressions when handling other failures such as generator disconnects, etc.

I take the corrective action as advised in the QRH, but it never has an effect.

 

Thus my question if it is possible to fight a failure or if failures are "definite" and can't be corrected (unless by turning it off in the FMC menu of course)?

Ps.: If it's not possible to take action against a failure at the moment, might I suggest it as a feature for the upcoming 747 v2? That'd be great!

Any chance for a comment on this part, too?

Just interested if it's indeed that unlikely that a failure can be resetted as in the example with the generator, or if this is something not modelled entirely.

 

You know, I tend to say in a PMDG plane you indeed have to ask twice whether that is a bug or a feature haha