Introducing the update of the Cessna 337 Skymaster

[captainjack]

Hello,
I am writing in November of 2016.
It seems that the last post in this thread was in 2014.
Is there still any interest in discussion about the 337?
Is anyone still here?
I love this aircraft, it is so skilfully created, exceptionally elegant in all of its presentation and behavior, and I hope to find others who are still interested in talking about it.
cj

[danten66]

I have to say that I love this plane and have a great time with it. If a paintkit was available I would probably make use of it

Thanks for putting this one together.

Dan

[Necolatis]

Found this by chance, dont know if it has useful info: https://ntrs.nasa.gov/archive/nasa/casi ... 010159.pdf

[wlbragg]

Can you provide a list of the updates?
If the original or current maintainer doesn't volunteer, I will volunteer to review the work and commit it to fgaddon.

[Catalanoic]

He was on the now offline ViveFG! spanish community, you can still reach him by mail, PM me if interested.

[wlbragg]

Thanks FlyingHigh, I will take a look at this and see if I can verify your observations.

[wlbragg]

I'm not sure I am seeing what you are.
This is what I see when switching from bat to alt



The gauges correspond to the properties. Can you be a little more specific? By buss 1 and 2 are you referring to bat and alt?

I re-read your post and it is true the "avionics" switch appears to have no effect on the amp flow. It appears to only be tied to the radio stack as well.

None of the breakers are active so I assume this electrical buss is still a work in progress.

[wlbragg]

I looked at the electrical code and I am curious to know what you have in mind. I am not totally familiar with how this all works internally. But I have worked on the c173p electrical which is more advanced than the 337 so I am guessing I could get around in this.
I don't know if these electrical connections and linkages are finished or complete. They appear to be missing some components or I think you would at least see the amp meter respond to power needs.
I see no nasal or system xml that is manipulating all the inputs and outputs. So again, it appears to me this was a work in progress.

Code: Select all

<?xml version="1.0"?>
 
   <!-- 28 Volt electrical system -->

<PropertyList>

   <!-- SUPPLIERS -->

<supplier>
   <name>Battery 1</name>
   <prop>/systems/electrical/suppliers/battery[0]</prop>
   <kind>battery</kind>
   <volts>28</volts>
   <amps>17</amps>
</supplier>

<supplier>
   <name>Alternator 1</name>
   <prop>/systems/electrical/suppliers/alternator[0]</prop>
   <kind>alternator</kind>
   <rpm-source>/engines/engine[0]/rpm</rpm-source>
   <volts>28</volts>
   <amps>60</amps>
</supplier>

<supplier>
   <name>Alternator 2</name>
   <prop>/systems/electrical/suppliers/alternator[1]</prop>
   <kind>alternator</kind>
   <rpm-source>/engines/engine[1]/rpm</rpm-source>
   <volts>28</volts>
   <amps>60</amps>
</supplier>

<supplier>
   <name>External 1</name>
   <prop>/systems/electrical/suppliers/external[0]</prop>
   <kind>external</kind>
   <volts>0</volts>
   <amps>0</amps>
</supplier>

   <!-- BUSSES -->

<bus>
    <name>Main Bus</name>
    <prop>/systems/electrical/outputs/bus[0]</prop>
</bus>

<bus>
    <name>Avionics Bus</name>
    <prop>/systems/electrical/outputs/bus[1]</prop>
</bus>

   <!-- OUTPUTS -->

<output>
   <name>Starter 1 Power</name>
   <prop>/systems/electrical/outputs/starter[0]</prop>
</output>

<output>
   <name>Starter 2 Power</name>
   <prop>/systems/electrical/outputs/starter[1]</prop>
</output>

<output>
   <name>Cabin Lights Power</name>
   <prop>/systems/electrical/outputs/cabin-lights</prop>
</output>

<output>
   <name>Instrument Power</name>
   <prop>/systems/electrical/outputs/instr-ignition-switch</prop>
</output>

<output>
   <name>Fuel Pump Power 1</name>
   <prop>/systems/electrical/outputs/fuel-pump[0]</prop>
</output>

<output>
   <name>Fuel Pump Power 2</name>
   <prop>/systems/electrical/outputs/fuel-pump[1]</prop>
</output>

<output>
   <name>Landing Light Power</name>
   <prop>/systems/electrical/outputs/landing-light</prop>
</output>

<output>
   <name>Beacon Power</name>
   <prop>/systems/electrical/outputs/beacon</prop>
</output>

<output>
   <name>Flaps Power</name>
   <prop>/systems/electrical/outputs/flaps</prop>
</output>

<output>
   <name>Turn Coordinator Power</name>
   <prop>/systems/electrical/outputs/turn-coordinator</prop>
</output>

<output>
   <name>Map Lights Power</name>
   <prop>/systems/electrical/outputs/map-lights</prop>
</output>

<output>
   <name>Instrument Lights Power</name>
   <prop>/systems/electrical/outputs/instrument-lights</prop>
</output>

<output>
   <name>Strobe Lights Power</name>
   <prop>/systems/electrical/outputs/strobe-lights</prop>
</output>

<output>
   <name>Taxi Lights Power</name>
   <prop>/systems/electrical/outputs/taxi-lights</prop>
</output>

<output>
   <name>Pitot Heat Power</name>
   <prop>/systems/electrical/outputs/pitot-heat</prop>
</output>

   <!-- AVIONICS OUTPUTS -->

<output>
   <name>ADF Power</name>
   <prop>/systems/electrical/outputs/adf</prop>
</output>

<output>
   <name>Audio Panel 0 Power</name>
   <prop>/systems/electrical/outputs/audio-panel[0]</prop>
</output>

<output>
   <name>Audio Panel 1 Power</name>
   <prop>/systems/electrical/outputs/audio-panel[1]</prop>
</output>

<output>
   <name>Autopilot Power</name>
   <prop>/systems/electrical/outputs/autopilot</prop>
</output>

<output>
   <name>Avionics Fan Power</name>
   <prop>/systems/electrical/outputs/avionics-fan</prop>
</output>

<output>
   <name>DME Power</name>
   <prop>/systems/electrical/outputs/dme</prop>
</output>

<output>
   <name>HSI Power</name>
   <prop>/systems/electrical/outputs/hsi</prop>
</output>

<output>
   <name>NAV 0 Power</name>
   <prop>/systems/electrical/outputs/nav[0]</prop>
</output>

<output>
   <name>NAV 1 Power</name>
   <prop>/systems/electrical/outputs/nav[1]</prop>
</output>

<output>
   <name>Transponder Power</name>
   <prop>/systems/electrical/outputs/transponder</prop>
</output>

   <!-- GENERAL CONNECTIONS -->

<connector>
   <input>Battery 1</input>
   <output>Main Bus</output>
   <switch>
      <prop>/controls/engines/engine[0]/master-bat</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Alternator 1</input>
   <output>Main Bus</output>   
   <switch>
      <prop>/controls/engines/engine[0]/master-alt</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Alternator 2</input>
   <output>Main Bus</output>
   <switch>
      <prop>/controls/engines/engine[1]/master-alt</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>
<!--
<connector>
   <input>External 1</input>
   <output>Main Bus</output>
</connector>
-->

   <!-- MAIN/AVIONICS BUS CONNECTION (AVIONICS POWER) -->

<connector>
   <input>Main Bus</input>
   <output>Avionics Bus</output>
   <switch>
      <prop>/controls/switches/master-avionics</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

   <!-- MAIN BUS CONNECTIONS -->

<connector>
   <input>Main Bus</input>
   <output>Starter 1 Power</output>
   <switch>
      <prop>/controls/engines/engine[0]/starter</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Starter 2 Power</output>
   <switch>
      <prop>/controls/engines/engine[1]/starter</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Cabin Lights Power</output>
   <switch>
      <prop>/controls/circuit-breakers/cabin-lights-pwr</prop>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Fuel Pump Power 1</output>
   <switch>
      <prop>/controls/engines/engine[0]/fuel-pump</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Fuel Pump Power 2</output>
   <switch>
      <prop>/controls/engines/engine[1]/fuel-pump</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Landing Light Power</output>
   <switch>
      <prop>/controls/switches/landing-light</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Beacon Power</output>
   <switch>
      <prop>/controls/switches/flashing-beacon</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Flaps Power</output>
   <switch>
      <prop>/controls/circuit-breakers/flaps</prop>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Turn Coordinator Power</output>
   <switch>
      <prop>/controls/circuit-breakers/turn-coordinator</prop>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Map Lights Power</output>
   <switch>
      <prop>/controls/switches/nav-lights</prop>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Instrument Lights Power</output>
   <switch>
      <prop>/controls/circuit-breakers/instrument-lights</prop>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Strobe Lights Power</output>
   <switch>
      <prop>/controls/switches/strobe-lights</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Taxi Lights Power</output>
   <switch>
      <prop>/controls/switches/taxi-lights</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

<connector>
   <input>Main Bus</input>
   <output>Pitot Heat Power</output>
   <switch>
      <prop>/controls/switches/pitot-heat</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

   <!-- AVIONICS CONNECTIONS -->

<connector>
   <input>Avionics Bus</input>
   <output>ADF Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>Audio Panel 0 Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>Audio Panel 1 Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>Autopilot Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>Avionics Fan Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>DME Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>HSI Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>NAV 0 Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>NAV 1 Power</output>
</connector>

<connector>
   <input>Avionics Bus</input>
   <output>Transponder Power</output>
</connector>

</PropertyList>

[wlbragg]

Yes, I see the same. I would like to know what your fix is?
Beware, turning the master "bat" off and leaving an alternator in-line should also cause the power to not be turned off. But the fact is even when you turn off both the front and rear alternator circuits and the bat, you still get power, which is not correct

[wkitty42]

obviously whatever is supplying the voltage is not monitoring those switch properties like it should be... you need to find where that voltage is being put into the system and make it follow the switches instead of being "true" all the time...

[wkitty42]

what FDM is this craft using? jsbsim or yasim?
if jsbsim, have you looked at how the c172p does it?

i don't know anything about yasim other than it is fairly simple and makes some assumptions that jsbsim doesn't... it may not have the ability to turn the power off once it is turned on... most of the yasim craft i've flown required me to restart the sim if i messed up some how... (eg: flipping the wrong switch, crashing, etc...)

[wlbragg]

It's JSBSim.
I started looking at the electrical system but haven't checked everything. I think controls/lighting/panel-norm may have something to do with it but I haven't traced it throughout the system yet. I did a quick search and did not see where it is created so I am wondering if it is a tied property coming from the core code?
Then again it isn't really associated with the buss creation at the core of the electrical.
I'm investigating more intensely at this moment and should have some answers shortly.

[wlbragg]

I'm going to post some discoveries as I go so as to not loose them.

If the master switch is on it ever so slowly drains the battery, regardless of alternator switches being on or off.



The following "Avionics Switch" looks suspicious! Why is it assigning every electrical output to 0 regardless of toggle position?

Code: Select all

<animation>
   <type>pick</type>
   <object-name>Switch_21</object-name>
   <visible>true</visible>
   <action>
      <button>0</button>
      <repeatable>false</repeatable>
      <binding>
         <command>property-toggle</command>
         <property>controls/switches/master-avionics</property>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/adf</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/audio-panel[0]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/audio-panel[1]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/autopilot</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/avionics-fan</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/dme</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/hsi</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/nav[0]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/nav[1]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/transponder</property>
         <value>0</value>
      </binding>
   </action>
</animation>

These are the conditions for one of the comm radios
instrumentation/comm[0]/serviceable
instrumentation/nav[0]/serviceable
instrumentation/comm[0]/power-btn
/systems/electrical/outputs/nav[0]

This is the condition for its knobs
controls/lighting/panel-norm

Code: Select all

<supplier>
   <name>Battery 1</name>
   <prop>/systems/electrical/suppliers/battery[0]</prop>
   <kind>battery</kind>
   <volts>28</volts>
   <amps>17</amps>
</supplier>

<bus>
    <name>Main Bus</name>
    <prop>/systems/electrical/outputs/bus[0]</prop>
</bus>

<bus>
    <name>Avionics Bus</name>
    <prop>/systems/electrical/outputs/bus[1]</prop>
</bus>

<connector>
   <input>Battery 1</input>
   <output>Main Bus</output>
   <switch>
      <prop>/controls/engines/engine[0]/master-bat</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>


<connector>
   <input>Main Bus</input>
   <output>Avionics Bus</output>
   <switch>
      <prop>/controls/switches/master-avionics</prop>
      <initial-state>off</initial-state>
   </switch>
</connector>

The problem is the "Main Bus" never goes to 0 it is either draining when the battery switch is on or at a constant 28 when it is off.
Why?
The link of "Main Bus" is like a symlink, where is it located and how does it work?
I am at the same place you are @FlyingHigh.
Gary Neely (aka 'Buckaroo') system implements nasal as well as the c172p, is this fundamentally why these aircraft implement nasal solutions?
It would not be difficult at all to simply replace the "system" xml with a nasal alternative, from scratch! But why is this original xml ever used in this manner if it doesn't work?

[wlbragg]

Or you could use the xml alternative with adjustments that do not use these "symlink's".

For example see https://github.com/arktools/jsbsim/blob ... trical.xml

[wlbragg]

I'm not sure how or why this works this way, but the fix is to do essentially what is done in the comm radio code.
In Models/Cessna337.xml starting at 1335, set to 0 all properties controlled by the bus...

Code: Select all

<animation>
   <type>pick</type>
   <object-name>Switch_01</object-name>
   <visible>true</visible>
   <action>
      <button>0</button>
      <repeatable>false</repeatable>
     <binding>
         <command>property-toggle</command> 
         <property>controls/engines/engine[0]/master-bat</property>
      </binding>
    <binding>
         <command>property-assign</command> 
         <property>/systems/electrical/outputs/bus[0]</property>
      <value>0</value>
      </binding>
    <binding>
         <command>property-assign</command> 
         <property>/systems/electrical/outputs/bus[1]</property>
      <value>0</value>
      </binding>
          <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/adf</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/audio-panel[0]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/audio-panel[1]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/autopilot</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/avionics-fan</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/dme</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/hsi</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/nav[0]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/nav[1]</property>
         <value>0</value>
      </binding>
      <binding>
         <command>property-assign</command>
         <property>systems/electrical/outputs/transponder</property>
         <value>0</value>
      </binding>
   </action>
</animation>