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Re: P-51D stall and spin: make it milder at takeoff and land

Postby wlbragg » Wed Dec 16, 2015 7:46 pm

my preference/suggestion would be that one of the more senior contributors (Curt?) should get in touch with hvengel's family and to keep the corresponding data until we have found a new maintainer

This needs to be done post haste, time can loose this valuable data and its meaningful exchange.

If you need a temporary US address you can use mine, PM.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby wlbragg » Wed Dec 16, 2015 8:09 pm

Thanks @dany93, as advertised!
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby Hooray » Wed Dec 16, 2015 8:36 pm

I agree with Thorsten, maybe some of our 2D artists could help create custom liveries/splash screens dedicated to hvengel that we could get committed to fgaddon ?
Another possibility would be updating the about dialog accordingly.

Hal's family made it clear that he cared very deeply about the p51d and would love to see his work adopted and continued by other contributors - while it may seem difficult to find a single individual with comparable expertise in so many different fields, we may be able to find a team of contributors interested in military aircraft, and familiar with the FDM and various Nasal scripts.

In the meantime, coming up with p51d splash screens and liveries dedicated to hvengel would at least help ensure that people will be made aware of his work, and that the aircraft is looking for a maintainer.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby MIG29pilot » Thu Dec 17, 2015 1:53 am

I'll see if I can make a p-51 liv called "Hal's Heritage."
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby radi » Thu Dec 17, 2015 5:09 am

RIP hvengel.

Bomber wrote in Wed Dec 16, 2015 4:16 pm:FG has AI wingmen could it be made such that when selecting an AI wingmen one of the call signs for a wingman be assigned Hvengel.


I actually really like Simon's idea, this way Hal will keep flying his own plane. Heliflyer comes to my mind, too.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby Hooray » Thu Dec 17, 2015 10:19 am

Creating a simple AI scenario (wingman/pattern/hold etc) should be pretty straightforward, and it could be region specific, too.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby MIG29pilot » Thu Dec 17, 2015 1:54 pm

Does anyone have an old p51 livery I can work from?
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby dany93 » Thu Dec 17, 2015 2:20 pm

@MIG29pilot
The first livery I have known (Aug-Sept 2011).
http://www.mediafire.com/download/8fjwg ... -Models.7z
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby githlar » Tue Dec 22, 2015 3:22 pm

The issues with the P51-D that caused it to not start was a change to the <starter-torque> parameter in Engines/Packard-V-1650-7.xml. I had originally posted the p51d_autostart.zip on Hal's startup procedure video after not being able to get it started even after following that guide. Somebody from the IRC and I were able to track down the commit that broke it and I posted the fixed version and an autostart script to make my life a little easier to YouTube/Dropbox.

However, I just incorporated a couple more changes:

1. Re-added the <starter-torque> value with something that works (I had originally just commented it out)
2. Rotated the barometer model to read correctly
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby MIG29pilot » Tue Dec 22, 2015 4:10 pm

Be careful about changing the starter torque and rpm; I tried changing those a few months back and while the engine did start I accidentally went off the runway.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby dany93 » Tue Dec 22, 2015 4:41 pm

As I wrote it, I took the p51d_autostart.zip from efel's message. (maybe the same as the one you are talking about?)

Before, I had found that with
Code: Select all
<starter-torque> 200 </starter-torque>
or
Code: Select all
<starter-torque> 300 </starter-torque>
(instead of 100) the engine could start manually. As it is more simple to comment it out and I don't see a drawback, why not?

@ githlar:
What is the difference between your script and this one? In what is it better? Or is it the same?
What barometer model?
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby githlar » Sun Dec 27, 2015 5:14 am

The autostart is no different, I haven't made any changes to it. I was just saying that I updated the Dropbox file to include a fixed barometer model as well -- something I noticed was off while I was tinkering with the plane after writing the autostart script (actually, I've just now updated it a second time to put the fixed altimeter/barometer model in the correct directory). It was off by something like -8.5° if I remember correctly. As I can't actually contribute to FGAddon, I figured perhaps you could incorporate it into yours since, as of this writing, yours is the only well published P-51D that actually starts.

My comment on Hal's YouTube P51-D startup tutorial video seems to have been deleted at some point, but that's where efel got the Dropbox link originally, I kind of wish he would have at least given credit where credit was due rather than making it seem as if he created the link.

I'm not sure where the <starter-torque> value came from originally, as I wasn't able to find any documentation regarding the value that was in there, only the JSBSim documentation on the default value if it's omitted. But, the value that's in SVN repo of course didn't work to get the engine started, a glaring oversight. Originally I commented it out in my p51d_autostart.zip file as well, but I felt that it was put there for a reason and found that <starter-torque> 150 was close enough to the original and actually worked.

@MIG29pilot I don't see any adverse effects using 150 as a starter torque value, though the plane does have a tendency to spaz out if you don't taxi it a little ways before increasing throttle. I think this is just a model collision somehow rather than due to the <starter-torque> value.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby dany93 » Sun Dec 27, 2015 2:14 pm

@githlar
1- I think I see what you mean about the barometer. The indicated pressure is not in accordance with the Internal Properties, e.g. 30.0 indicated on the instrument instead of 29.964 (/instrumentation/altimeter/setting-inhg). [EDIT] After better observation, I'd say that the instrument display is rather +0.02 to +0.03 inhg above the setting-inhg Property. [/EDIT]
Am I right?
However, I'm not sure because...
I don't understand your -8.5° (animation angle for the altitude needle?). I find that the indicated altitude on the instrument (needle) is in rather good accordance with the Internal Properties (instrumentation/altimeter/indicated-altitude).

To test and include your barometer fix, I need your changes, by an access to your Dropbox file or, as it seems simple, the line(s) that you changed in the file. Mere code here to copy.

2- Your Autostart patch:
I don't know where people can find a link for your patch, else than efel's message.
After better reading, I'm not so sure that efel made it seem as if he created the link. Or maybe not on purpose.
efel wrote in Wed Jun 24, 2015 2:38 pm:It fits well, and by hand too... the problem seems fixed
.
If you wish to be credited for it somewhere in the aircraft's files, please tell me how and where (a comment in engine-start.nas? I don't see a contributors "readme").

Currently, I have no access to SVN or FGAddon, just github. I don't know how that will work later.

but I felt that it was put there for a reason and found that <starter-torque> 150...
Maybe. I don't know.
Last edited by dany93 on Mon Dec 28, 2015 6:29 pm, edited 3 times in total.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby dany93 » Sun Dec 27, 2015 2:50 pm

MIG29pilot wrote in Tue Dec 22, 2015 4:10 pm:Be careful about changing the starter torque and rpm; I tried changing those a few months back and while the engine did start I accidentally went off the runway.

githlar wrote in Sun Dec 27, 2015 5:14 am:@MIG29pilot I don't see any adverse effects using 150 as a starter torque value, though the plane does have a tendency to spaz out if you don't taxi it a little ways before increasing throttle. I think this is just a model collision somehow rather than due to the <starter-torque> value.

Not sure that it is connected to your messages but, by the way...

An unpleasant bug remains, known by hvengel but he couldn't succeed to solve it.
viewtopic.php?f=49&t=24808&start=30#p227792
viewtopic.php?f=49&t=24808
viewtopic.php?f=25&t=22657
When the sim is started with a tail wind, it crashes the sim or throws the aircraft, sometimes at starting of the engine, or when you begin to roll, when the (relative) wind changes from tail to front. If you happen to get it, try with head wind or / and on another runway. Also, avoid increasing the throttle with the parking brake ON.
Sorry and needless to say, fixing this bug is currently well above my knowledge, despite I'm trying to understand the issue.
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Re: P-51D stall and spin: make it milder at takeoff and land

Postby erik » Sun Dec 27, 2015 3:03 pm

dany93 wrote in Sun Dec 27, 2015 2:50 pm:An unpleasant bug remains, known by hvengel but he couldn't succeed to solve it.
viewtopic.php?f=49&t=24808&start=30#p227792
viewtopic.php?f=49&t=24808

When the sim is started with a tail wind, it crashes the sim or throws the aircraft, sometimes at starting of the engine, or when you begin to roll, when the (relative) wind changes from tail to front. If you happen to get it, try with head wind or / and on another runway. Also, avoid increasing the throttle with the parking brake ON.


I ran into this when developing the J3 Cub too. It seems to effect taildraggers more than others.


I got these too a couple of times, when fiddling with the gear spring and damper setup.
Lowering both solved it for me.

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