Md-11 Flightplan Problems: Kbos-bikf

[drdickie 2]

I am attempting to fly an Icelandic route from KBOS-BIKF. I am using the AIRAC 0812 data, and an actual flightplan I got from FlightAware for December 9. The plan is: KBOS-PSM-ENE-J55-PQI-J564-TAFFY-N153C-STEAM-OYSTR-(5600N-0500W)-(6000N-0400W)-(6300N-0300W)-EMBLA-BIKF. All of the waypoints were accepted by the MD-11, and looked proper when reviewed in plan mode. The time and fuel consumption look about right. However, in flight somewhere around PQI-TAFFY, the magenta track disappears even though all the waypoints are still in the computer flightplan. The waypoint STEAM still appears at the top of the map display. The aircraft does not seem to know where it is and ends up about 180 degrees off course. Any suggestions?Thanks.

[downscc 1,327]

I cannot verify my hunch, but I think the problem is fix N153C. I don't have current navdata at work but my old copy does not have this fix in the wpNavFIX.txt file. When you verifed the route in Plan view did this fix appear in the route?

[Guest j-mo]

N153C is a route (high altitude, IIRC), not a fix.

[drdickie 2]

As I stated in the original message, all looked fine in plan view. And, N153C is a route.

[downscc 1,327]

Of course, it was a cold morning and my brain had a slow start. I have too verifed the route and assuming nothing is wrong with it; did you lose the PROF predictions at the time that the ND stopped displaying the course?

[KCA9304 0]

[ (5600N-0500W)-(6000N-0400W)-(6300N-0300W) ]Have a look at the West coordinates, zero's are missing.Should read, 05000W... 04000W... 03000W.How/what did you enter in the MCDU Flightplan?Regards,Harry

[drdickie 2]

The coordinates were entered with the correct number of zeros. In fact, I think you have to enter them as N5600.0/W05000.0 to not get a format error. I note that all the waypoints have Lat/Long to one decimal point when you check them out.The last time I tried this flight, the A/P disconnected and the aircraft began a slow diving turn to the left. The only way I could get out of it was to go direct to BIKF. I recall something like this in FS9 on a STAR into KSFO (PYE?) where there was a scenery problem--anyone else recall that?I found another route flown by ICE630 which doe not involve PQI-TAFFY but have not had time to try it yet.Just to check out my system, I tried a flight from KORD to KLAX entering some of the waypoints as Lat/Long. Everything worked just fine.Thanks for all the comments.

[downscc 1,327]

I agree you used the correct shortcut for lat/lon (for others, see article in PMDG Ops knowledge base: http://ops.precisionmanuals.com/wiki/FMC_WP_Entry_Notes ) but I sure would like to figure this one out. My understanding is A/P disconnected, so I wonder if you lost PROF forecasts?? You said the flight plan fixes ahead were still in the FMS but did they have time/speed/alt info??Loss of PROF is a separate problem from loss of A/P. If it was just loss of A/P then I would look for speed variations due to weather winds or temperature, frozen fuel maybe, etc. There is a reason the A/P disconnected and it doesn't sound like a scenery/route problem yet (unless it will repeat the problem at the same location).

[drdickie 2]

I was flying without weather or winds. I have never ever encountered a frozen fuel problem. I will give it another try and pay more attention this time -- I was grading exams when the last occurrence happened and was brought out of my reverie by "autopilot...autopilot...."Thanks. By the way, Dan, did you ever figure out the "too many runways" at KORD problem?

[drdickie 2]

A new finding... I attempted this flight again today. All was perfectly normal until passing ENE and 113 nm from PQI when FSX froze and the sound went from normal to something like a rapidly repeating beat/buzz. I let it run like this for about 5 minutes. The only way I could exit was to restart my computer by holding in the power button. This has never happened to me before. I can't say that the two events are related but it is odd.

[drdickie 2]

Another new finding...I flew this route using the PMDG 747, loading in the saved flightplan from the MD-11 flights. It flew successfully through PQI, but 5.2 nm from TAFFY, I got an altitude alert and the aircraft began to descend. The AP stayed on. At TAFFY, the aircraft flew through the waypoint and did not turn toward STEAM. After trying to get things straightened out, I discovered that the controls were frozen -- no climb, no turn, no response to LNAV, VNAV, etc. The route still appeard on the map, all waypoints were present in the computer. I did notice that the speed at STEAM was listed at 0.843 -- all other waypoints were listed at 0.852. The other fact I noted was that no T/D was calculated for BIKF. Even though the runway appears (11), the altitude was listed as FL390, the cruise level along the route.I am puzzled...

[downscc 1,327]

You got a live one, don't you? These problems are frustrating but interesting. If I get a chance this afternoon, I may try it for myself but there have been many successful NATS flights and then there is this one. Have you ruled out addon sceneries? You don't have to uninstall them, just deselect in the scenery library manager and restart.Yes, the ORD too many runways problem was odd. It is cause when the total number of runways and approaches exceeds a number, and PMDG has my bug report. No feedback on that problem yet because they are trying to get the FS9 MD11 out to everyone.

[downscc 1,327]

I am on your flight plan now, just past TAFFY enroute to STEAM at FL330 with the MD11F using ASX for weather. The only challange was the shifting 130 kt wind from a left quartering headwind to a tailwind, which in the MSFS world causes a loss of airspeed that had to be managed by overriding PROF for a few minutes until the shift was done.So I am pretty sure the problem is not AIRAC 0812 nor the MD11. Hope this helps.

[drdickie 2]

Another data point...I flew the same route using the 0812 AIRAC with the Level D 767...no problems at all along the route. If you have no problems with MD-11, I guess I will have to look elsewhere.The only add-on I have on my system is FSGenesis scenery. Do you think that could be a problem? But why would the outcome be different with the MD-11, 747-400, and LDS-767 if it was scenery?Thanks for the KORD update.

[downscc 1,327]

Yeah, it is strange. The only thing I can suggest, once you can reproduce the problem with the MD11 and it occurs in the same location, is to turn off the scenery. This is an easy step, turning them on and off only requires checking/unchecking boxes and restarting MSFS. If you can rule out the navdata, the aircraft and the weather (this is also a likely candidate) then all that is left is the scenery files.Make sure you are not having a weather related problem. Note I had to turn PROF off to survive... the wx engine is the worst thing about MSFS.