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Project Apollo Beta 7.0 released!
http://nassp.sf.net/wiki/Installation
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Author Topic: TLI problem  (Read 2582 times)
av8rjim
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« on: April 18, 2009, 03:40:42 PM »

    I am an orbiter veteran, but new to NASSP beta.  I launched using the Apollo 11 pre-launch scenario, performed all checklist items up through TLI, and began plotting my course using IMFD as instructed in the Apollo 11 mission checklist.  I have followed all the directions, and got my radius to 1.660M and PeT to 75:05:21GET.  The problem occurs after the Apollo MFD is set and the vehicle is oriented for TLI.  For some reason I have yet to be able to identify, the craft is oriented in an attitude which is pitched around 30 degrees downward in relation to Earth.  As a result, during the burn my PeA intersects Earth's atmosphere, and the mission shortly comes to a screeching halt on terra firma.  Is there something wrong in the Apollo 11 checklist, or have I misconfigured the spacecraft?  Thank you very much in advance.

-Jim
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Tschachim
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« Reply #1 on: April 18, 2009, 05:21:48 PM »

Please make sure that you're using the lastest IMFD and NASSP version, there was an interface change lately. Other than that you could post/attach a scenario saved before the burn, so we can take a look.

Cheers
Tschachim
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jarmonik
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« Reply #2 on: April 18, 2009, 05:38:45 PM »

Ok, here is a link to latest build of IMFD. I will make it officially available after fixing remaining issues. Hopefully during this month.

http://koti.mbnet.fi/jarmonik/InterMFD52b2.zip
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av8rjim
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« Reply #3 on: April 22, 2009, 05:29:34 AM »

Awesome, the new version of IMFD worked beautifully.  I'm well on my way to the moon now.
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Shadow Addict
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« Reply #4 on: April 28, 2009, 10:31:09 PM »

I had the same problem with the Apollo 8 vAGC scenario, and it's been driving me crazy. I'll try the new version of IMFD.

EDIT: No good. I just downloaded the new IMFD linked above and put the .dll in the Modules\Plugins folder (is that right?), activated it and began using it. I still orient about 40 degrees downward torwards Earth and get sent blazing down when TLI starts.

Here's one of my recent quicksaves with IMFD set for TLI (at least it should be, I quicksave pretty often so I usually start forgetting them pretty fast >_>).

« Last Edit: April 28, 2009, 11:10:24 PM by Shadow Addict » Logged
jarmonik
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« Reply #5 on: April 29, 2009, 04:37:03 AM »

There is something wrong. It didn't work during first attempt however during second attempt everything worked fine. There seems to be some kind of random error. I don't have more time right now.
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Shadow Addict
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« Reply #6 on: April 29, 2009, 07:59:24 AM »

There is something wrong. It didn't work during first attempt however during second attempt everything worked fine. There seems to be some kind of random error. I don't have more time right now.

Odd. Well, thanks for giving it a try. I'll try setting up the TLI a few more times and see if it works.

EDIT: My P30Comp. Mode under Config is set to 1 instead of 2, could that be causing the problems? (I have no idea what that means or if it has any impact at all but I noticed I'd set it wrong)
« Last Edit: April 29, 2009, 08:34:55 AM by Shadow Addict » Logged
jarmonik
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« Reply #7 on: April 29, 2009, 08:50:59 AM »

EDIT: My P30Comp. Mode under Config is set to 1 instead of 2, could that be causing the problems? (I have no idea what that means or if it has any impact at all but I noticed I'd set it wrong)
P30Comp mode is directly related to attitude control. Latest version of NASSP is using P30Comp mode 1 where as older versions are using P30Comp mode 2. There was an interface change while ago as Tschachim pointed out few posts above.
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jarmonik
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« Reply #8 on: April 29, 2009, 09:25:37 AM »

This is somehow scenario depended problem. In your scenario attitude control sequence will start approximately T-578 and this will take the vessel with-in 36 degrees from correct attitude. (typically this is below 0.2 degrees)  Approximately at T-488 an other attitude control sequence will start taking the vessel with-in 0.01 degrees from correct attitude. This sequence was skipped in my first test. Your TLI scenario do have different behaviour than other ones I have tested. I don't know why.   
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Shadow Addict
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« Reply #9 on: April 29, 2009, 10:18:54 AM »

One question, does P30Comp. Mode matter while the TLI is being set or while it's being executed? Because I think I used Mode 2 to set it in those scenarios.
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jarmonik
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« Reply #10 on: April 29, 2009, 12:45:00 PM »

One question, does P30Comp. Mode matter while the TLI is being set or while it's being executed? Because I think I used Mode 2 to set it in those scenarios.
It does matter when the burn is being executed or you are waiting time of ignition but it shouldn't effect behaviour of the course program when seting up the course. It's better to keep it in mode 1 always.

EDIT: So far I haven't been able to reproduce the problem that occured during the first attempt.
« Last Edit: April 29, 2009, 12:59:55 PM by jarmonik » Logged
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« Reply #11 on: April 29, 2009, 06:13:03 PM »

Okay, I went back to a save well before I set up IMFD and did it completely freshly. This time, when I TLI'd, I oriented to about 0 degrees relative to the Earth, which I assumed was correct (I didn't get the chance to see the results of the burn as my computer crashed for totally unrelated reasons about twelve seconds into the burn). I saved right before, so I'm going to go see if it worked!

EDIT: The burn seems to have been right on. Thanks for the help!
« Last Edit: April 29, 2009, 06:31:13 PM by Shadow Addict » Logged
jarmonik
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« Reply #12 on: May 06, 2009, 08:13:51 AM »

Here is a link to latest build of IMFD52 http://koti.mbnet.fi/jarmonik/IMFD52.zip
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