Summoner

Well, it was that or continue the flight with an unknown problem with a flight control that could potentially get worse, and since I am not paid to be a test pilot, the choice was an easy one. All of the fuel and payload were loaded via the PMDG 747 load manager. I read the warnings about using the built-in FSX payload and fuel utilities, and since I prefer to have my aircraft functioning properly, I make it a point to use the utilities provided by PMDG. On a side note, I had the opportunity to perform a properly modeled 747 fuel dump on this flight, which was something of a positive. Maybe I am a little bit odd for thinking that, I dunno.

I was attempting to fly a cargo flight from Bangkok to Tokyo today in FSX, when I ran into an odd flight control issue that I have never seen before (though I certainly can't say that I have seen them all). Please keep in mind that this was only my 5th flight with the PMDG 747 (another awesome product, btw!), so the problem could very well have been me. Let me describe what happened... As I was approaching my initial cruise altitude of FL330, I noticed that the IAS was about twenty knots slower than the 331 knots the FMC had calculated for the climb (it got a little bit closer when the FMC switched over to Mach, but it was still slow). I thought that was a little odd, but I wasn't in danger of stalling the aircraft so I let it be. What started ringing alarm bells in my head (and in the cockpit) was when the autopilot blew right through FL330 and kept climbing. I turned LNAV off and switched to LVL CHG to get back to FL330, and the autopilot very slowly stopped its climb and began a descent back to the correct altitude. I started poking around to find out what was wrong, when I noticed on the EICAS STATS page that the elevator was deflected full nose-down. I immediately checked the trim setting, and it was in the green arc, set to 4.8 units. I disconnected the autopilot and bumped the elevator, which immediately reset the elevator to neutral and gave me a huge climb due to the trim. I manually re-stabilized the aircraft at FL330 and trimmed out the elevator needed to maintain altitude, then re-engaged the autopilot. The autopilot immediately re-trimmed to 4.8 units, which sent my altitude crazy again (and disconnected the autopilot) until it got back to FL330, but with full nose-down elevator. I returned to Bangkok, and kept an eye on the trim and elevator status the whole way back. The entire descent, approach, and landing, the autopilot kept the trim set to 4.8 units, and the elevator gradually decreased its nose-down deflection as the speed decreased. I am just wondering what may have gone wrong for the autopilot to always use the same trim setting regardless of airspeed, and deflect the elevator to compensate. Is it something that I may have done (or neglected to do)? The trim setting used by the autopilot is not the one that I set for takeoff, which was 6.0 units. Could it be some kind of malfunction with my hardware? I did see an FSX pop up dialog message when I started the simulator asking if I wanted to run an .exe file that I didn't recognize, so I said no, but that turns out to be something related to my X52 Pro joystick, which I reinstalled the drivers for yesterday. The joystick appeared to be functioning normally throughout the flight, though. I also did not have any failures set to occur in the PMDG 747. I am not sure when I will have time to try to reproduce this issue. Since I am no longer going to be flying for a few hours, I am going to be working on chores around the house. I am curious to know if anyone has experienced a similar event though, and any ideas regarding what I can do to prevent it from happening again.

I never claimed that Navigraph data was perfect. However, I learned long ago to double-check all routes entered in a FMC in any Flight Sim addon. Navigraph is better than any other navdata source I have seen.

A simple solution to make lives easier for the VATSIM controllers is to include a note similar to "Default scenery" in the comments of your flight plan. That way they know if the scenery you are using may be out of date and can plan for it ahead of time. In regards to the original question about Navdata, most addons now use Navigraph's service (not just aircraft addons, either). It is actually a really good deal since you only have to get a pack update once, and you can download that update for all of your addons that use Navigraph's service. The AIRAC updates every 28 days, but Navigraph's updates are cheap enough that you should be able to update every two or three cycles, if not every one. Another plus about Navigraph, is that you can get charts from them as well (though I only use it for those countries where charts are not available for free). As for why PMDG doesn't do their own AIRAC updates, it just isn't in their business model. It is easier to program their (incredible) aircraft to accept navdata from another provider than it would be to create their own navigation database (which would end up being almost identical to what Navigraph already provides). The downside, of course, being that if Navigraph ever shuts down, we are all up the proverbial creek.

From what I can remember of a few flights in a 737 simulator a few years back, 30 degrees of flaps is the standard setting, 40 is used for short-field/steep approaches, and 15 is used for single-engine approaches. On a side note, I read an interesting question not too long ago. What would happen if a nerf had a high midichlorian count? Almost makes you wonder about that steak you just ordered.

Thanks for the information, Andrea. I was aware of the fuel scavenge system, but not the details of how it operated. I have flown the NGX several times previously, with varying fuel levels, without encountering this problem before. In this flight, both wing tanks were full and I had fuel in the center tank as well, and all fuel pumps were on. I'm not entirely sure the scavenge system is to blame in this instance though, since the fuel level in the #2 tank was going down at a rate of about 10 lbs every 15-20 seconds, while the #1 tank remained full. The fuel level in the center tank was also decreasing, but I expected that. Does the bug you described cause the fuel scavenge system to draw fuel out of the #2 tank instead of from the center tank? If so, where was that fuel going? Now that I think about it, the rate at which the fuel level in the center tank was decreasing may have been a bit slower than normal. I'll be attempting this flight again at some point, and I'll try to recreate this issue. @Chris: This is an excellent example of why checklists are good at combating complacency. I already knew that, though.

No, I shut down the APU once both engines were started and running. I actually feel quite stupid for switching the electrical system over to the engines and forgetting about the pneumatic system.Anyway, I'm not sure the APU would burn off 2,000 lbs of fuel in half an hour.

Yes, I wasn't very clear. The warning horn drew my attention to the fuel imbalance, but the horn was because I hadn't turned the packs and bleed air back on after starting the engines. I did mention I was a bit rusty. :(

I use service based failures for all of my NGX flights, but what I meant in my OP was that when I checked the failures in the FMS after shutting down, there were no active failures that needed to be cleared. If there was a fuel leak, I would have expected to have seen at least one active failure in the fuel system. I loaded the default cold and dark panel state before the flight, and did use the NGX fuel and payload loading system instead of the FS system.

Good evening, fellow pilots. I just ran into a bit of a head-scratcher. It could very well be something I did, since I have not had the time to do much flying lately and may have missed something in my cockpit flows. I was attempting a flight from GCLP to LEBL, and everything was fine until climbing through FL130 when a warning horn began to sound and a Fuel Imbalance was indicated in the #2 tank (it was already almost 1,000 lbs less than the #1 tank). After landing back at GCLP, with almost a 2,000 lb difference between the wing tanks and a little over 11,000 lbs in the center tank, I checked the failures to clear them, only to find that there were no failures active. So, now I'm wondering what happened to that missing 2,000 lbs of fuel in the #2 tank, and what (if anything) I may have done to make it go somewhere else. The crossfeed valve was closed, and all fuel pumps were on at the time the warning horn started to sound (I turned off the #2 pumps just to make sure I wasn't pumping fuel overboard, and the fuel level continued to decrease). The lack of failures makes me suspect that I may have accidentally done something (or not done something) to cause this to happen. Any thoughts or suggestions would be greatly appreciated.

So if I understand correctly, even if I have set ASA to refresh the weather every 20 minutes (or whatever timeframe), the program will only download new weather if the reported weather has changed since the last check? That makes sense. Good to know. :(

If this has already been covered, I apologize. I scanned through several pages of the forums and did not see my particular issue addressed, so here goes. I have noticed while using ASA with FSX that even though I have set the options to refresh the weather every 20 minutes, ASA will frequently be using weather that is up to an hour old.I have tried changing the refresh period, with and without VATSIM weather, it doesn't seem to help. I am completely stumped and was wondering if a fresh set of eyes might be able to help me out here.Another thing I noticed, and it's a trivial thing, is that every time I start ASA, the "Cancel" and "Save and Apply" buttons are illuminated in the Options screen. I don't think any of my settings have changed (at least I haven't noticed any changes), but it always leaves me wondering since they are grayed out after you click the Save button until you make another change.

I've had this happen to me twice in the past few days. Both occurred in South America in the Colombia/Peru area. The first time my aircraft descended several thousand feet to maintain the set Flight Level for an hour or two then returned to a more normal altitude, and the second time I had to climb several thousand feet. The second time affected my approach to Lima by being well above the maximum setting for the altimeter and leaving me about 3,000 feet too high. A quick refresh seemed to fix the problem though.Unfortunately I did not think to save the weather in either instance. If it happens again I'll make sure to save the weather and try refreshing it right away to see if that helps.