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Shuttle launch problems

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Shuttle launch problems

Postby mixam » Sun Jan 21, 2018 5:09 pm

Whenever I try to launch the space shuttle atlantis, upon SRB ignition the whole craft just pitches over and explodes. It naturally has a tendency to point the nose down at launch, but whenever I try to correct it pitches over backwards quite drastically and I get the same result. Help?
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Re: Shuttle launch problems

Postby Thorsten » Sun Jan 21, 2018 5:14 pm

What version of the Shuttle are we talking about (aka, from where did you acquire it)?

The current version has a fully automated launch procedure (you would not even need to touch the stick) and even if you take over manually, the DAP is a rate-controlled scheme, i.e. the Shuttle would hold current attitude if you let go of the stick.

For an overview over the automated procedure, please see

http://wiki.flightgear.org/Flying_the_Shuttle_-_Launch

In case you are flying manually - is your control device perhaps giving spurious signals (we've once had a set of pedals always sending a yaw input which was pretty bad for launch...)?

There's also a (rather annoying and difficult to reproduce) bug with placement _in_ the pad rather than on the pad which can lead to a sudden 'kick' at launch - but what you describe doesn't sound like that (?)
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Re: Shuttle launch problems

Postby mixam » Sun Jan 21, 2018 7:08 pm

I tried using the autopilot, but immediately after ignition it causes the shuttle to pitch forward excessively and fly along the ground. I got the shuttle from the standard flightgear hangar
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Re: Shuttle launch problems

Postby wkitty42 » Sun Jan 21, 2018 11:55 pm

where are you launching from? i don't know that that will make any difference but it is possible...
"You get more air close to the ground," said Angalo. "I read that in a book. You get lots of air low down, and not much when you go up."
"Why not?" said Gurder.
"Dunno. It's frightened of heights, I guess."
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Re: Shuttle launch problems

Postby mixam » Mon Jan 22, 2018 1:37 am

I usually try to launch from baikonur cosmodrome or around cape canaveral at a heading of 270 so that with proper roll I will launch towards the east.
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Re: Shuttle launch problems

Postby Thorsten » Mon Jan 22, 2018 6:16 am

I still don't have a good feeling for what the problem is.

Could you set up a launch as described in the tutorial

http://wiki.flightgear.org/Flying_the_S ... h_tutorial

and then check whether you are properly placed onto the pad (rather than onto the ground with the pad draped over it) from outside view?

Then press 'h' till you see the FG-native HUD and zoom out till you can read the upper left entry which is the current control mode?

Then look at the launch guidance in the GUI whether it is active and at the eyebrow panels whether the PITCH and YAW/ROLL pushbuttons are in AUTO mode?

Also, does the Shuttle work okay for you in other situations (in orbit, during entry, in the atmosphere)? Or are there other problems?

And - the classic - any error messages about runtime errors (crashing guidance software?) written to the console/log?
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Re: Shuttle launch problems

Postby legoboyvdlp » Tue Jan 23, 2018 6:02 pm

I take it you are using the Space Shuttle in FGADDON, mixam?
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Re: Shuttle launch problems

Postby bugman » Wed Jan 24, 2018 7:18 pm

There are multiple versions of the Shuttle, but the major two are:


Then there are unofficial mirrors of these, with modifications unknown to the original authors (so these are also different versions).

Regards,
Edward


P. S. There is actually an undocumented second Shuttle in FGAddon, but this is solely an old FDM, i.e. no 3D model.
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Re: Shuttle launch problems

Postby mixam » Fri Jan 26, 2018 12:58 am

I am using the FGAddon shuttle. The shuttle seems to be placed properly on the pad and the pitch, yaw, and roll are set to auto.
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Re: Shuttle launch problems

Postby Thorsten » Fri Jan 26, 2018 5:36 am

Then press 'h' till you see the FG-native HUD and zoom out till you can read the upper left entry which is the current control mode?

Then look at the launch guidance in the GUI whether it is active

(...)

Also, does the Shuttle work okay for you in other situations (in orbit, during entry, in the atmosphere)? Or are there other problems?

And - the classic - any error messages about runtime errors (crashing guidance software?) written to the console/log?
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Re: Shuttle launch problems

Postby Abdullah Radwan » Fri Nov 30, 2018 8:52 am

I've got the same issue. Any help?
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Re: Shuttle launch problems

Postby Thorsten » Fri Nov 30, 2018 9:05 am

The same set of questions - what is 'the same issue'? Can you describe in detail what you're doing and what happens as a result?
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Re: Shuttle launch problems

Postby Abdullah Radwan » Fri Nov 30, 2018 9:11 am

I am using the normal Flight Gear Launcher with command line set to --aircraft=SpaceShuttle-launch --lat=28.6206 --lon=-80.6133 --heading=270 --timeofday=morning

I start the APU using the checklist and everything is set to AUTO. Then I press Shift + I then lift off. Seconds later, the pitch is going forward excessively and the SRBs are separated and the shuttle is smashed into the ground.

I didn't touch the joystick. All of this is automatically done.
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Re: Shuttle launch problems

Postby Thorsten » Fri Nov 30, 2018 9:32 am

Are you initially placed properly on the pad? What happens at a different location?

Is there an error message in the console? (the fact that SRB separate is... more than unusual). About the only way this happens when they're not empty is an explosion of the whole stack).

(You're describing issues we don't see and can't reproduce, so I can't give a solution, the cause has to be established first).
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Re: Shuttle launch problems

Postby Abdullah Radwan » Fri Nov 30, 2018 11:22 am

I've fixed the issue by running FlightGear from the command prompt (Or Windows PowerShell) with the following command:
.\fgfs --aircraft=SpaceShuttle-launch --lat=28.6206 --lon=-80.6133 --heading=270 --timeofday=morning
--prop:/sim/rendering/multi-sample-buffers=1 --prop:/sim/rendering/multi-samples=4 --prop:/sim/rendering/shaders/skydome
=true --disable-rembrandt --geometry=1920x1080 --enable-fullscreen --enable-terrasync --enable-real-weather-fetch --prop
:/nasal/local_weather/enabled=true

It works now without any problems.
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