Hi folks,

 

checking curiously on whether there is an undetected failure, I found really one:

'EMDP A HYD LEAK' on the hydraulics page, but so far no indication on the real displays, gauges etc.

QTY% A is during my current flight (EHAM-KLM1673-LEBL) stable at 69%.

 

Hmm, let's wait whether something happens.

 

What is it?

Am I able to detect it without peeping into the Failed Items page?

If not, waiting is the best I can do.... 8^)

I don't know about this failure specifically, and I'd defer to Andrea for any specifics, but remember that the aircraft isn't from Skynet and doesn't come with a sensor array attached to everything. As such, you're not going to get a direct indication for every failure on the EICAS.

 

Take a look at this article and note that the first indication was oil temp/pressure-related. After that it was a fuel imbalance. At no point did the EICAS say anything was leaking. All indications were indirect.

http://en.wikipedia.org/wiki/Air_Transat_Flight_236

Thanx Kyle.

Totally fine for me not to get the tiniest information displayed.

Exactly these evolving failures are an outstanding feature of PMDG sims...

 

However, a hyd A leakage should manifest itself at some stage by a decreasing hyd A level, should it not?

However, a hyd A leakage should manifest itself at some stage by a decreasing hyd A level, should it not?

 

Unless EMDP means "Extremely Minor Dripping Puncture," at some point, yeah. That would be my guess. I'd have to defer to those with specific 737 knowledge, though.

Suppose that EMDP means Electrical Motor Driven Pump, I would not be surprised if the leak manifested only when the engine driven pumps are not in use. But who knows.

 

Either way this asks for a mechanics advice. I know as a pilot what kind of pumps there are and how they are, but I dont know the tubing...

I don't know about simulated leakages of the ngx, but, there are no EICAS messages except for low quantity RF (REFILL) wich is visible only on ground.

If pmdg did the same as for fuel leakage the quantity leakage is random, each time a leakage occurs the value is always different. But I don't know if it works on the hyd leakage.

However, yes, hydraulic QTY will slowly decrease to 0 (for EMDP circuit leakage)

You will see the first master caution message at about 20% of QTY as the EDP (engine) pump will start to pump air as inside the reservoir it has an higher pipe to "save" sufficient fluid for EMDP usage.

So, At 20% of quantity the ENG PUMP LOW PRESSURE light and master caution will come on.

It is too late....the EMDP pipe will pump skydrol untill the reservoir is empty.

Now, if the leakage is just after the pump, turning the pump off (and still more than 20% of fluid) will stop the leakage, if not, prepare to lose the A system.

I think you must wait an hour or more to see if the leakage is present, look at the quantities.

I think you must wait an hour or more to see if the leakage is present, look at the quantities.

 

Nope, still stable amount of hyd fluid, even after my return flight LEBL-KLM1674-EHAM.

Maybe the fault is an artefact and I have to delete it.