Undercarriage retracts automatically.

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Location: California

Post by Winstonc »

Just loaded sim-a 1.8 and 1.8 737 model and again the undercarriage is behaving correctly and not auto-retracting.


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Joined: Tue Jan 06, 2015 11:04 pm
Location: Sydney - Australia

Post by MichaelYSSY »


Well I followed David's lead and loaded SA 737Aircraft 1.8 and Sim Avionics 1.8

The first flight the gear behaved its self the second time I used the sim it's back to gear retracting on its own straight after positive rate.
I checked from an external view and can confirm that the gear retracts in FS and plays FS gear retract sound only.
When I move gear lever up up position the Sim Avionics sound plays.

I then restarted the rig with FS only and no Sim Avionics connected and after takeoff and positive rate I can confirm that the gear does NOT retract by its self.

Anyone have any ideas?

SSTD 737
Sim-Avionics v1.96
P3D 4.5/5.0 HF1
FSUIPC 6.0.8

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Joined: Wed Jan 18, 2006 5:08 am
Location: UK

Post by MarkHastings »

Do you load a 'Scenario' before flying ?
The Gear lever state may be getting loaded from the scenario.
In this case try selecting the checkbox on the Control Panel "Do Not load system with Scenarios"

Second, How is your gear lever assigned ?
On the Sys controller there are 3 options Gear UP, Gear OFF, Gear Down.
FDS Gear levers usually have an UP and a DOWN microswitch, so you should have a switch event assigned to Gear UP and a switch event assigned to Gear DOWN.
Nothing on "Assign 2"
No OFF Events.

Lastly, On v1.80 I added a log file that may help me to diagnose certain situations.
Please can you start and fully load your sim ready for flight.
Then goto the Server menu > System > Create Support Debug Files
This will create 9 files in a folder in "\Server" called "\SUPPORT_INFO".
Please zip up these files and mail them to me.

FYI: If you open "Server_Debug_Data_New.log" a few lines down you'll see the current Commanded Gear Position.

You can monitor the FS gear offset using the Server FSUIPC Monitor.
This is how the lever is currently set in FS.
The offset is 0BE8
Type = 4 Unsigned
(0 = UP, 1 = DN)
Mark Hastings
Software Developer

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Joined: Wed Mar 09, 2016 11:12 am
Location: California

Post by Winstonc »

Hi Mark

I already have "Do not load system with Scenarios" checked.

I have the up input and down inputs assigned to the On inputs,
I do however have the up and down inputs off events assigned to Gear Off, so I guess that may be the issue although I am not sure why as the gear lever is in the down position when I take off and yet I still get an UN-commanded retract. I will clear everything for the Gear Off position and see if that fixes the problem.

I will check again and create a log file.



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Joined: Thu Dec 08, 2016 9:35 pm

Post by hillryanc »

I'm not sure if this is the "solution", but I've found that only by starting from cold & dark do I not get the gear problem. I also don't get the gear problem after the first takeoff (cycling of gear) if not starting from cold & dark. Something is clearly bugged with the "initial state" scenario (or appears to be).

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