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Alouette III overhaul

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Alouette III overhaul

Postby Thorsten » Sun Nov 19, 2017 7:04 pm

I've started to give the Alouette III a thorough overhaul, adding support for many things FG added in recent years (tooltips, checklists, effects and shaders,...)

I've also taken the opportunity to adapt the excellent rotor particles from the EC-135 and tinker a bit with it - this might be of interest for other helicopter developers.

The particle system is now completely environment-sensitive - on dusty ground there will be lots of yellowish dust stirred by the rotor, on water there will be white spray instead, if the helicopter flies above the snowline there'll be snow swirling, and also rain, environment wetness or dustiness are recognized. Also, the particle system adapts to ambient lighting as well as the aircraft landing light.

Engine start during a rain shower:

Image

The rotors cause water spray on the wet apron which is illuminated by the heli lights:

Image

I've tried to make this sort of an example case for other aircraft developers in that there's pretty much everything (ALS glass with rain and frost, ALS rotor wash, ALS lightspots, rotor wash dust particles,...) handled by one single class, the effect manager

This doesn't necessarily mean that I would recommend to do everything in Nasal (some things could equally well be implemented as JSBSIm system or property rule), but this presents all that's needed in a fairly clear and transparent structure in one place. It also illustrates a few performance-friendly tricks like the usage of property node reference pointers to streamline property I/O or checking of results against Nasal-records before doing any property I/O. Or to simply run only what's needed...


It should be fairly straightforward to adapt the effect manager to other use cases at the simple expense of changing the value of some variables and driving it using different properties.
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Re: Alouette III overhaul

Postby wlbragg » Mon Nov 20, 2017 3:52 am

I flew this heli a couple days ago so I think after I updated it no longer starts. I tried Autostart first and it acts like it is going to start by starting to spin up then it just slows down the spinning slightly. I tried manual and get same results.
Engine start checklist all show green except Turbine RPM sits at >18000 (yellow).

There is the following line in the log, however I don't know the significance.
Code: Select all
In file /home/wayne/.fgfs/Aircraft/org.flightgear.fgaddon/Aircraft/Alouette-III/Engines/artoust3b.xml: line 86
Note: Using the EnginePowerVC without enclosed <function> tag is deprecated
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Re: Alouette III overhaul

Postby Thorsten » Mon Nov 20, 2017 7:34 am

I get the same line (I haven't really changed any engine-related stuff) - the original file apparently pre-dates a JSBSim change, and this needs to be changed to the new format, but the message seems harmless, JSBSim falls into compatibility mode.

It runs for me fine on last stable as well as on a 2016 snapshot - I haven't tried next yet, but unless it's a very recent patch that caused breakage, I can't reproduce it.

(I assume you have waited a bit? It takes a while to spin up, first the turbine and then the rotor).
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Re: Alouette III overhaul

Postby wlbragg » Mon Nov 20, 2017 5:00 pm

(I assume you have waited a bit? It takes a while to spin up, first the turbine and then the rotor).


Yes, I pretty much waited indefinitely :)

I looked under the hood a bit to try to figure out what was stopping it from firing up and couldn't identify it. Maybe it is something to do with the qtlauncher, when or how it updates aircraft. I'll pull a direct copy from fgaddon and see if it works for me.
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Re: Alouette III overhaul

Postby wkitty42 » Mon Nov 20, 2017 7:03 pm

i just updated everything here and just used the autostart... it took about a minute or so for the rotor sound to start when it did kick in... i didn't hear any motor whining during the spin up period, though... first time in the craft... just autostarted and then exited 'cause i don't have all the controls to properly fly a heli though $deity knows i've tried several times :mrgreen:

Code: Select all
** Build Info: **
***********************************************************************
PLib:    a542b8a03f8de1fe844af6ab4734b64d11e272e9
OSG 3.4: f3607134a2a2fa3279976b1edc50e1f2e3b3cd82
Simgear: e12fc5a89d1b0171b0668ce2af595be7c726aa80
FGFS:    089abcfe40479b24990671538c39a8dc0ff8f5ce
FGData:  457251ed470500dca18e5c4a980e01f6ec534fbe
FGAddon: r3101 | trenk | 2017-11-20 06:26:09 -0500 (Mon, 20 Nov 2017)
***********************************************************************
"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: Alouette III overhaul

Postby Thorsten » Mon Nov 20, 2017 7:06 pm

i didn't hear any motor whining during the spin up period, though...


There's no turbine sound yet (never was apparently) - I'm not at this point of the overhaul that I changed the sound config.
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Re: Alouette III overhaul

Postby lzu164 » Mon Nov 20, 2017 7:13 pm

Thorsten wrote in Mon Nov 20, 2017 7:34 am:I get the same line (I haven't really changed any engine-related stuff) - the original file apparently pre-dates a JSBSim change, and this needs to be changed to the new format, but the message seems harmless, JSBSim falls into compatibility mode.

It runs for me fine on last stable as well as on a 2016 snapshot - I haven't tried next yet, but unless it's a very recent patch that caused breakage, I can't reproduce it.

(I assume you have waited a bit? It takes a while to spin up, first the turbine and then the rotor).


Hi, thanks for updating this great machine. It's my favorite helicopter in FG, and everything works great here.

About the message regarding the engine: I fixed this by changing the code to this:
Code: Select all
<function name="EnginePowerVC">
  <description> Engine power, function of airspeed and pressure </description>-->
    <table>
    <independentVar lookup="row">atmosphere/P-psf</independentVar>
    <independentVar lookup="column">velocities/ve-kts</independentVar>
    <tableData>...
    </tableData>
    </table>
    </function>


This would seem to make the copter actually be able to ascend to a proper cruise altitude. Without this I couldn't get over 4000ft. I'm not sure if this is correct though?
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Re: Alouette III overhaul

Postby wkitty42 » Mon Nov 20, 2017 7:17 pm

Thorsten wrote in Mon Nov 20, 2017 7:06 pm:
i didn't hear any motor whining during the spin up period, though...


There's no turbine sound yet (never was apparently) - I'm not at this point of the overhaul that I changed the sound config.

cool! i thought i was maybe missing something or had gone deaf :)
"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: Alouette III overhaul

Postby wlbragg » Mon Nov 20, 2017 7:24 pm

Well, now I'm pissed. Everyone else's works but mine. It just sits there and slowly turns. It won't kick up. The original does using the startup config menu.
I even checked it out from fgaddon directly.

See anything obvious? In the panel I notice the ac is nil. Is it animated and supposed to have a value?
Image
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Re: Alouette III overhaul

Postby wlbragg » Mon Nov 20, 2017 7:25 pm

Hold on. I think I know what it might be!
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Re: Alouette III overhaul

Postby wlbragg » Mon Nov 20, 2017 7:29 pm

:oops: Do not try to start helicopters at airports that are above their ceiling! :oops:
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Re: Alouette III overhaul

Postby lzu164 » Mon Nov 20, 2017 7:44 pm

lzu164 wrote in Mon Nov 20, 2017 7:13 pm:Hi, thanks for updating this great machine. It's my favorite helicopter in FG, and everything works great here.

About the message regarding the engine: I fixed this by changing the code to this:
Code: Select all
<function name="EnginePowerVC">
  <description> Engine power, function of airspeed and pressure </description>-->
    <table>
    <independentVar lookup="row">atmosphere/P-psf</independentVar>
    <independentVar lookup="column">velocities/ve-kts</independentVar>
    <tableData>...
    </tableData>
    </table>
    </function>


This would seem to make the copter actually be able to ascend to a proper cruise altitude. Without this I couldn't get over 4000ft. I'm not sure if this is correct though?


The above can be discarded, sorry. After actually checking the weight of the copter, the original code yields correct performance. Models weight is 4884lb and hover ceiling for that is about 4265ft.
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Re: Alouette III overhaul

Postby wkitty42 » Mon Nov 20, 2017 8:35 pm

wlbragg wrote in Mon Nov 20, 2017 7:29 pm::oops: Do not try to start helicopters at airports that are above their ceiling! :oops:

that'll do it! ya gotta have some additional bottled air to feed them when they are that high... just like airplanes... we had this with the c172p, too ;)
"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: Alouette III overhaul

Postby LesterBoffo » Tue Nov 21, 2017 3:18 am

wlbragg wrote in Mon Nov 20, 2017 7:29 pm::oops: Do not try to start helicopters at airports that are above their ceiling! :oops:


This is odd, as the later AS Lama was famous for setting altitude records, and the Alouette III shouldn't be that far down on power in comparison. :?:
Isn't the turboshaft engine in both pretty much the same except for shaft H.P.?
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Re: Alouette III overhaul

Postby wlbragg » Tue Nov 21, 2017 4:05 am

I was starting up at VQPR which WIki states is at 2,235 m (7,332 ft). So no, it really wasn't that high. But that altitude was high enough to not allow it to start. When I went to Warner Springs airport CL35 which is 878 m (2880 ft ) (estimated) it started fine.
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