777X "Landing"? itself (or how would you call that)...

[BK 1]

This is really strange and I could not find anything in the forum related to such an issue.

1. It happens only in long haul flights. You can see in the SS that time in flight was 8:28 hours en route EGLL-WSSS. When it happens it always happens in the last third of the flight (Time-wise).

2. The problem: The 777x "Lands" itself in an uncontrollable manner. The engine still running, everything looks good (except of the impact of the "landing" like tail strike for example).

See that even the landing gear somehow drops down for landing, all by itself... How can this happen, I wonder.

3. Obviously I do not seat at the sim in such a long flights. I am by the sim until cruise level and then I activate the "Auto-cruise" feature (today I tried x4 only and it still did it) and leave. If I come back too late, the T7 is on the ground (FSX crash detection is disabled).

4. I saved the panel state and files can be shared if required.

5. I can certainly say that it does not happen in short haul flights. Yesterday I did a 3.5 hours flight WSSS-VHHH and it was fine using X16 acceleration. I was sitting by the sim for the time it took (about an hour+).

Machine specs attached. It’s not the most advanced rig but 777X runs just fine with the help of EXTREME FSX PC from FSPS.

 

Appreciate if anyone can pick this up and provide a hint as to which direction to go here. Until such time no long haul flights...

 

Thanks

Benny K

[3-2-1-Now 126]

What screenshots? I wish people would check that they are actually attached.

 

The gear will auto-extend if you bounce the aircraft gear-up IIRC (an FS-ism), but otherwise what you describe is totally impossible.

 

Best regards,

Robin.

[thomazz123 11]

HUH?

[BK 1]

HUH?

Exactly the right response. I am saying that every time I see that...

BK

[Mike777 163]

The problem: The 777x "Lands" itself in an uncontrollable manner. The engine still running, everything looks good (except of the impact of the "landing" like tail strike for example).

 

See that even the landing gear somehow drops down for landing, all by itself... How can this happen, I wonder.

 

3. Obviously I do not seat at the sim in such a long flights. I am by the sim until cruise level and then I activate the "Auto-cruise" feature (today I tried x4 only and it still did it) and leave. If I come back too late, the T7 is on the ground (FSX crash detection is disabled).

 

H, Benny,

 

I don't think the PMDG T7 is meant to be flown all the way to touchdown in autocruise/4X.  Try setting "Pause at top of descent (TOD)" if you are going to be away from your computer.  Looks like the plane is just following its flight plan as best it can until it bounces on the runway, making the gear come down, as Robin said.  It won't go into approach mode by itself; you need to be there to do it.  Another solution: set a hold before touchdown so the plane will just keep circling until you come back.

 

What altitude is set in the autopilot?  It should never descend below that altitude unless it runs out of fuel or the autopilot is disconnected.

 

Mike

[BK 1]

Right. It seems the autopilot is somehow disconnected as it looses lateral and vertical navigation. However, I wonder why that happens because the screenshot shows AP still engaged.

[kamaz74 81]

The easy fix to this is not to use time compression OR monitor the airplane during time compression. Did this happen during cruise or after the TOD point? I wouldn't even consider using time compression during climb and descent. Does your airplane do step climbs automatically or is that disabled in the simulation options?

 

While we're at it, update your magdec.bgl with the 2013 file. 

 

http://www.aero.sors.fr/hfiles/MagDec_Update.zip

[Mike777 163]

You are at 8000 feet, but the temperature is 25°C. If you have too high temperature at high altitude, the plane won't climb. It is possible that the aircraft could even fall out of the sky, although I have not seen that happen even with high temperature at high altitudes. You may have some program that is creating high temperatures at high altitude.

 

Mike

[Kerlix 99]

One time in the MD-11 I fell asleep part-way through an 11-hour flight. Before I went to sleep I checked to made sure that "Pause at TOD" was enabled. When I woke up the plane was on the ground, wheels down in a weird valley about 800 miles from my destination, on an island in the middle of the Pacific.

 

 

I could never figure out how the gear came down and it managed to land on a spec of land in the middle of the ocean haha. I guess FSX "self-lowered" the gear when the plane bounced. And the island.....pure luck.

 

 

So while I can't offer a solution, I can tell you that something similar has happened to me once in the past.

[BK 1]

The easy fix to this is not to use time compression OR monitor the airplane during time compression. Did this happen during cruise or after the TOD point? I wouldn't even consider using time compression during climb and descent. Does your airplane do step climbs automatically or is that disabled in the simulation options?

 

While we're at it, update your magdec.bgl with the 2013 file. 

 

http://www.aero.sors.fr/hfiles/MagDec_Update.zip

Thanks for that. If you don't use time compression, you know how long it takes... And, monitoring it all the time is out of the question.Do you think it's due to time compression?

It happens during cruise and not after TOD. What you see in the screen shot is time 08:28 hours into a 12 hours flight (more or less). Step climb is automatic in my options.

Benny

One time in the MD-11 I fell asleep part-way through an 11-hour flight. Before I went to sleep I checked to made sure that "Pause at TOD" was enabled. When I woke up the plane was on the ground, wheels down in a weird valley about 800 miles from my destination, on an island in the middle of the Pacific.

 

 

I could never figure out how the gear came down and it managed to land on a spec of land in the middle of the ocean haha. I guess FSX "self-lowered" the gear when the plane bounced. And the island.....pure luck.

 

 

So while I can't offer a solution, I can tell you that something similar has happened to me once in the past.

That's a good description of what's happening in my case, just replace the MD11 with the T7... I decided and executed a re-install... we'll see in few days how / if this helped.

Benny

[Mike777 163]

 

 

It happens during cruise and not after TOD. What you see in the screen shot is time 08:28 hours into a 12 hours flight (more or less). Step climb is automatic in my options.

 

Hi, Benny,

 

The more I think about it, the more it looks like a weather issue.  I occasionally had incidents similar to yours and Kerlix's in FS9, when I wasn't at my computer naturally.  You had an altitude set, you didn't run out of fuel, so the plane should never have descended, no matter what your flight plan.  And,as you said, you were only 2/3 into your flight.  I think the most likely explanation is a sharp, unrealistic change in winds and/or temperatures, and the autocruise couldn't switch back into 1X fast enough to allow the plane to adjust.  FSUIPC can fix some of these issues.  Another suspicious factor:  25o C at 8,000 feet, as showing on your panel, is very high in most cases.  Where did the plane come down?

 

Mike

[BK 1]

Hi, Benny,

 

The more I think about it, the more it looks like a weather issue.  I occasionally had incidents similar to yours and Kerlix's in FS9, when I wasn't at my computer naturally.  You had an altitude set, you didn't run out of fuel, so the plane should never have descended, no matter what your flight plan.  And,as you said, you were only 2/3 into your flight.  I think the most likely explanation is a sharp, unrealistic change in winds and/or temperatures, and the autocruise couldn't switch back into 1X fast enough to allow the plane to adjust.  FSUIPC can fix some of these issues.  Another suspicious factor:  25o C at 8,000 feet, as showing on your panel, is very high in most cases.  Where did the plane come down?

 

Mike

It is 157NM from KENAL (as you can see on the screen shot). I think it's on the Himalayan somewhere (North of India). This is why altitude is 8300 feet and if you look carefully in the screenshot you can see the mountain where the aircraft put itself. 25 deg C? In the Himalaya? Don't think so...

Anyway, I am using OPUS SW for weather and so far did not have problems with it flying the NGX for hundreds of flights.

KENAL     N3703.4 E06246.7 N644 122 90 3286

In any event I already re-installed and we'll see the results during the upcoming weekend.

 

Benny

[IEFlyer 0]

The aircraft is on the ground in the screenshot above - see the radio altimeter reading.

[FLEX1978 373]

hehe, I would of thought it was obvious the aircraft was on the ground from the PFD

[Mike777 163]

 

 

This is why altitude is 8300 feet and if you look carefully in the screenshot you can see the mountain where the aircraft put itself. 25 deg C? In the Himalaya? Don't think so...

 

I knew it was on the ground at 8000 feet.  But the EICAS is showing a TAT of 25o C, which, as Benny said, is highly improbable.  So if the temperature is off at ground level, it might have been off at altitude, causing a problem with the aircraft's ability to remain in flight. 

 

However I just noticed something else: the PFD shows that the autopilot is set to 33000 ft, but it also indicates "ATT" mode.  I am not at my FS computer now, but I think this means the ADIRU might have failed.  At any rate, "ATT" mode may mean that the aircraft is not following the altitude set in the autopilot.

 

Mike