Had a strange failure today when I went to go fly today. I turned the avionics on and it went through business as usual except the heading compass never appeared on either of the EHSI. Instead there was a "HDG" caption displayed on the screen with the lubber line. The rest of the text such as LNAV, DME, waypoints and stuff were displayed around the perimeter of the gauge. Just no full or partial compass. Was reading through the manual and it said a failure would be denoted by an amber C on the EADI in the upper corner of the pitch/roll gauge. Ultimately my question is that since the failure module was not implemented how are we supposed to reset the failures? I went into the FSX failure menu thinking that maybe that triggered but there was no failure selected there, and hitting the reset all failures button did nothing. Tried turning off the avionics and waiting for them to reset. Also tried switching between computers 1 and 2 on the combing panel. So curious to see if I just need to reload the whole aircraft when that happens or if there is a particular way to reset it. Also if anyone else has seen it? I would say it is a bug but according to the manual the system is working exactly as advertised or this failure. Reference Chapter 8.11 page 20. Thanks in advance for any help.

I'm not sure about the compass being missing entirely, but it's possible to get a Heading Comparator fault if you have the Vapor Cycle Cooling on. Operation of the system causes the CA's and F/O's headings to disagree, and you should get the [C] on the AEDI along with Heading flag on the EHSI.If the compass is missing entirely, it sounds like an AHRS issue.Just to be clear, you're seeing what you think is a properly modeled failure scenario, right? Meaning there are flags and warnings associated with the missing data? Or are elements simply missing without proper failure indications?Nick

I think Nick is right, the Vapor Cycle Cooling will trigger a false failure, which is a fairly good reason why it cannot be used during flight.

It appears exactly as it is described in the AOM. With the amber C, and the "HDG" displayed on the lower tube. I just went to reload the sim to see if I could duplicate it but it works now. Go figure. If I see it again I am going to take a screen. Will see when I try to redo the hop tomorrow. Thanks for trying to help though. Just one of those random phantom things I suppose.Is this vapor cycle cooling switch on the FO side (above the test panel for the stall warning/fire lights/etc)? If so I was messing around with those switches over there and that may very well explain it..... Cause it was dark and I thought I was switching the ECS fans for the cockpit on.

It appears exactly as it is described in the AOM. With the amber C, and the "HDG" displayed on the lower tube. I just went to reload the sim to see if I could duplicate it but it works now. Go figure. If I see it again I am going to take a screen. Will see when I try to redo the hop tomorrow. Thanks for trying to help though. Just one of those random phantom things I suppose.Is this vapor cycle cooling switch on the FO side (above the test panel for the stall warning/fire lights/etc)? If so I was messing around with those switches over there and that may very well explain it..... Cause it was dark and I thought I was switching the ECS fans for the cockpit on.

Interesting, it appears that (Wishfull thinking) PMDG programmed an invisible failure module that is truley random and not known by the pilot.. LOL, or, that they started coding to complete all the systems and add a failure module, but stopped at some point leaving half the systems complete (also wishfull thinking, which would mean that completion of a full J41 simulation is partly done and was stopped because of FSX limitations or development resources)... All wishfull thinking.. :( JB

Or...and THIS is what happened...the programming of the EFIS is so complete that the vapor cycle cooling affects it exactly like it does in the real airplane, and the manual reflects it the way it is.This isn't a failure so much as operator error.

I will have to agree with EMB on this one... I wish I would have read more now instead of posting right away, lol. I was just completely caught off guard when it happened was all. At least now I know that Vapour Cycle switch does in fact do something...

Or...and THIS is what happened...the programming of the EFIS is so complete that the vapor cycle cooling affects it exactly like it does in the real airplane, and the manual reflects it the way it is.This isn't a failure so much as operator error.

I have to agree, the EFIS is done extremely well... Sorry, didn't mean to come off the wrong way with my comment...JB