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P3D v3 Fairchild C-123 Provider

Tankerguy72

Tankerguy72

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152
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us-california
After 7 good years of use I had to retire my old computer and bought a new one for Christmas. With the new computer I thought Id step up to 3DS max and give it a shot. Ive messed around with GMAX for quite a few years but I still consider myself a rookie modeler. So with that here is my newest project.







 
It reminds me this movie or a PC6 was to go in by cutting these wings to hide it from enemy aviation :)
 
Implementing the mixed propulsion is going to be tricky.

I predict quite a bit of community interest for this one.
 
If I had the unit size set to meters and plugged in the measurements to the objects as meters why is my sizing off? I get a warning about the unit size when I export.
 
Tankerguy72 said:
I get a warning about the unit size when I export...
Click to expand...

... because the System Unit isn't set to 1 metre. In Max, as in Gmax, you can have the viewport/modelling units set to metres, or millimetres, or inches, or feet but the System Unit must be set to 1 unit = 1 metre. In my version (2008) the System Unit is on the same dialog tab as the viewport/modelling units.
 
I'm not on the computer right now but last night I went on and click on customize dropped down to unit measure or something and confirmed the unit of measure was 1 meter. would I have to change it in the viewport tab also?
 
Tankerguy72 said:
That's what I was wondering... is it possible to have jets and props on one plane in P3D?
Click to expand...

Unless LM added mixed propulsion as a feature: No.

However, I 've successfully experimented with XMLTools, adding a dynamic offset to forward velocity for simulating JATO. This can just as well be used for mixed propulsion, although devising the equations and faking indications for the jet engine will be complex and a bit tricky.
 
Thanks Heretic I may need some help from you down the line after the model is completed.

Fixed the scale issue. I had made the changes in the Display Unit Scale, but I had missed where it said System Unit Setup. All good now, my provider is not the size of an airport anymore :D
 
OK This got me thinking. I'm still an FSX guy so P3D may be different. I got thinking about how engines are described in the aircraft.cfg file

Code: 
[piston_engine]
...
emergency_boost_type= 0                         //0=None, 1=Water Injection, 2=Methanol/Water injection, 3=War Emergency Power
emergency_boost_mp_offset= 0.0                  //Additional manifold pressure supplied by emergency boost
emergency_boost_gain_offset= 0.0                //Multiplier on manifold pressure due to emergency boost
...

If I recall correctly how the default P-51 racer works, you have to turn it emergency boost on and it lasts until the Methanol/Water runs out. So my thought is to "equip" the C-123's piston engines with a "hidden" emergency boost system. Tweak the system so that it simulates the additional power provided by the jets. When you start the "jets" you are really turning on the emergency boost.

Issues:
I am not familiar with the C-123's fuel system(s) so that may be an issue. If one system, start an fuel dump that starts when emergency boost is started. If two systems (which I would think t would have to be) a Methanol Water gage labeled "jet fuel"?

The jet "functions" would be "smoke-and-mirrors" - visual spinning turbines, smoky exhaust and jet sounds - again all triggered by turning on the emergency boost.

For the purists in the crowd, Yes, I realize that the jet thrust will not be coming from the correct position on the wing. Also, I don't know if you can do emergency boost separately for each engine so asymmetric thrust when you lose a jet would not be realistic.

I have no idea if it would work. It is not perfect - it raises all kinds of pressures and temperatures in the engine tat would have to be looked at…still… Thoughts?
 
Last edited:
That sounds pretty good. I'm ordering the manual for the Provider so that may answer some questions. I've never done any coding or anything so I welcome an suggestions or anyone that would like to help on the project. I can do modelling and textures but that the extent. The rest I'll have to learn or take any volunteers.
 
Getting the manual is a good idea. I have no idea how or when the C-123 used it jet engines - all the time? Take off and climb? Above certain altitudes? Above certain cargo loads?

I recall that in the move "Strategic Air Command", Jimmy Stewart was piloting a B-36 that developed engine trouble at cruising altitude. They decided to stat their four jet engines. It didn't work. The point being that they were cruising along just fine without the jets…of course that was a movie.

Still if the jets are only used for certain flight regimes, the "boost" method might be an acceptable simulation.

I am also a modeler - mostly building and static objects/aircraft for FSX Missions (simNovels)…once in a while I do a boat or vehicle - a much simpler issue when you take out that pesky third dimension. ;)

For aircraft, I don't get any deeper than the aircraft.cfg file. I opened an air file once - too complicated for me - however I am told "that is where al the magic happens". :)

Good luck wth this!
 
A recent discussion about WEP can be found here:
http://fsdeveloper.com/forum/threads/wep-switch.439201/

The thing about the default WEP functionality is that, despite looking easy, it will still require a lot of fiddling and masking. First of all, you have to get the correct performance for the piston powered part of the envelope, which is already a complex task. Then, the following issues have to be resolved:

1) Is it possible to get to combined propulsion performance spec with WEP? If yes, go on, if no, find another solution (such as XML Tools).
2) Find out if WEP can be applied per engine to properly simulate single jet engine operations (opposed to dual jet engine ops).
3) Make sure to make WEP only available once the virtual jet engines are spooled up.
4) Monitor manifold pressure behavior. If there's a gradual increase when using WEP, things will get much more complex, while an instantaneous offset can be easily accounted for in the gauge code.
5) Can the jet engines be throttled? If so, WEP won't be an otion.
5) Does the increased manifold pressure affect cylinder head temperature? If so, find a way to make the gauges show nominal levels.
6) Does WEP damage the engine? If so, you have to work around it.
7) Velocity and altitude affect jet engine performance. At least fake the gauge indications to reflect this.
8) If the jet engine uses its own fuel, you can simply use the WEP duration limiter to simulate this. Otherwise, you'll have to set up a really complex fuel management system.

There's probably much more issues that need to be considered and accounted for when using WEP. I'd only use it as a last resort.

An XMLTools based solution is not significantly easier to implement but is at least more flexible as it will leave the piston engine simulation alone.

But as I've said, try to get the piston powered part right before you tackle the jets.
 
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