Cargo Towing Addon

[Johan G]

I started reading up on Bambi Buckets again. There are buckets ranging from 72 US gal (270 L) all the way up to 2010 US gal (7600 L).

SEI Industries are nice in that they have plenty of documentation online, both catalog, and new and old operation manuals, service manuals and repair manuals are available. You can read out the height of the bucket straps between the bucket and control head (attached either to the helicopter or a longline), and the height of a filled and empty bucket from the operations manual.

I am kind of interested in doing maybe three sizes with and without longline. One small (BB1821, gross weight, GW, 1890 lb, 860 kg) for example for the Eurocopter AS350 Écureuil and MD500, one larger (BB2732, GW 2840 lb, 1290 kg) for example for the UH-60, and one huge (BBHL7600, GW 17190 lb, 7800 kg) for example for the CH-47, CH-53 and V-22.

[wlbragg]

I meant to tell you I have a decent bambi bucket model that I was eventually going to add to the cargo towing addon. I just hadn't got around to it yet. That would probably be the easiest way to implement one. It already has the longline available and also some code logic that can be adapted to fill it when submersed in a lake.

I don't know the size off hand, but a variety of sizes would be nice.

[LesterBoffo]

FGUK has a number of the helos listed on the CDF website that would be good candidates for the Bambi Bucket. You also have UH60s and CH47s from the US Army, USAF, CDF and private companies relaying supplies and equipment to the firelines and their crews from Sacramento at McClellan.

I mean the amount of activity that could be part of the operations from just what I've seen live on FR24's map is intense at times. 4 to 5 helos working in coordination with water drops, shuttling in supplies, running IR scans and spotting for the fixed wing water bombers, all within a couple miles of each other.

[LesterBoffo]

I started reading up on Bambi Buckets again. There are buckets ranging from 72 US gal (270 L) all the way up to 2010 US gal (7600 L).

I am kind of interested in doing maybe three sizes with and without longline. One small (BB1821, gross weight, GW, 1890 lb, 860 kg) for example for the Eurocopter AS350 Écureuil and MD500, one larger (BB2732, GW 2840 lb, 1290 kg) for example for the UH-60, and one huge (BBHL7600, GW 17190 lb, 7800 kg) for example for the CH-47, CH-53 and V-22.

I have Heiko's AW139 with a sidemounted winch. I wonder if the small Bambi Bucket would be better mounted on a quick release on the bottom of the AW139?

[wlbragg]

I did a quick test of the feasibility of adding the Bambi Bucket to the Cargo Towing Addon.

Here is proof of concept.

All that is needed after this is for me to write some custom code for the bucket fill and drop. The addon should allow you to fill it with one of three ways.
Using the Fuel and Payload menu (already available).
Any one of the 3 portable cargo tanks if that cargo tank is also available in the scene.
Or in any water source, stream, pond or lake.
Add logic to control some effects. Water dripping from bucket and water spray from the actual drop.

I think the logic will be added to the Cargo Towing Addon as that is the only way you can get the bambi bucket on any helicopter. I also will need to make sure the drop works with any aircraft using the Cargo Towing Addon or maybe the Wildfire addon.
This goes hand in hand with my attempt to add an independent addon for aerial firefighting or adding it to Wildfire. I think it would be best to be part of the Wildfire addon.

Note: Filling and dropping retardant going through the Cargo Towing addon allows for the addition of the weight of the water or retardant to to aircraft, as that logic is already in place for the cargo.

[Johan G]

Adding another helicopter to the add-on, is that as easy as adding it to Cargo-Towing-Addon/aircraft.xml, or should the data in that file be copied to the aircraft-set.xml? I did not really 100% understand the readme.

[Johan G]

I have Heiko's AW139 with a sidemounted winch. I wonder if the small Bambi Bucket would be better mounted on a quick release on the bottom of the AW139?

They are pretty much universally mounted as an external sling load as the bucket capacity is matched to max fuel load and/or max external load. I think the rescue winch is designed for two (heavy) guys with some safety margin.

On the other hand the smallest bambi bucket has a gross weight of a mere 670 lb (300 kg).

I did a quick test of the feasibility of adding the Bambi Bucket to the Cargo Towing Addon.

Here is proof of concept.

Nice!

I think the logic will be added to the Cargo Towing Addon as that is the only way you can get the bambi bucket on any helicopter. I also will need to make sure the drop works with any aircraft using the Cargo Towing Addon or maybe the Wildfire addon.

[...]

Note: Filling and dropping retardant going through the Cargo Towing addon allows for the addition of the weight of the water or retardant to to aircraft, as that logic is already in place for the cargo.

There is a lot of weight shed in a few seconds, so that is probably a good idea.


Edit 1: Hmm, maybe I should move a some of these posts to the cargo towing addon development topic. I did derail the topic a bit.

Edit 2: Moved some post from the Caldor Fire: Water Bombers, Helos, Pathfiders, Oh My! 9/9 event topic over here.

[wlbragg]

Yes, you just add it to the aircraft.xml in the addon
All you need to insure is that the loadpoint actually exists in the aircrafts fdm.

What aircraft are you going to add that is not in it already?

[LesterBoffo]

I'm not complaining. if the water bucket adds to an future wildfire online sessions it's a win. I have the earlier Sikorsky UH-60 from a really old FG aircraft download site that would be a good medium size Bambi Bucket test vehicle as it's cockpit is well animated yet the FDM and nasal operations are pretty basic. It is a bit buggy as it will only start with going into the property tree and switching on the engine magnetos through controls/ It's a nice stable platform to practice with.

[Johan G]

What aircraft are you going to add that is not in it already?

The FGUK MD500D and MD500E, probably the AS350 too, but I am really bad with that last one (it is very sensitive). In particular the AS350 is a popular helicopter for heli work here in Sweden, nearly all operators have it and maybe one or two other types.

Yes, you just add it to the aircraft.xml in the addon
All you need to insure is that the loadpoint actually exists in the aircrafts fdm.

I managed to add and play around with it on the MD500E. Will try the other later. These settings seem to work well (if I use the coordinates from the FDM, the rope end up neatly coiled on the cockpit floor ).

Code: Select all

    <aircraft n="31">
        <!-- weight x="0.5" y="0" z="1.2" mass-prop="/sim/weight[1]/weight-lb"/ -->   <!-- Long line -->
        <name type="string">500e</name>
        <x-pos type="double">1.75</x-pos>
        <y-pos type="double">0.0</y-pos>
        <z-pos type="double">0.325</z-pos>
        <offset type="double">3.75</offset>
        <diameter type="double">0.75</diameter>
        <wincharm type="int">0</wincharm>
        <loadpoint type="int">1</loadpoint>
    </aircraft>

I am surprised that even with my not so perfect helicopter skills I can feel when I have a load attached. On the other hand it probably took half an hour to get the rope end within even 300 ft of the load (I had not flown a heli for almost a month).


I had two Nasal errors just 50 and 85 seconds in, right after scenery was loaded, but before playing around with placing objects (these are consecutive lines from the log):

Code: Select all

   42.75 [INFO]:terrasync C:\Jenkins\workspace\Windows-release\simgear\simgear\scene\tsync\terrasync.cxx:837: Successfully synchronized directory 'Objects/e010n50/e018n58'
   49.97 [ALRT]:nasal     C:\Jenkins\workspace\Windows-release\flightgear\src\Scripting\NasalSys.cxx:1412: Nasal runtime error: non-objects have no members
   49.97 [ALRT]:nasal     C:\Jenkins\workspace\Windows-release\flightgear\src\Scripting\NasalSys.cxx:1430:   at __dlg:rope-dialog, line 33
   84.66 [ALRT]:nasal     C:\Jenkins\workspace\Windows-release\flightgear\src\Scripting\NasalSys.cxx:1412: Nasal runtime error: non-objects have no members
   84.66 [ALRT]:nasal     C:\Jenkins\workspace\Windows-release\flightgear\src\Scripting\NasalSys.cxx:1430:   at __dlg:rope-dialog, line 33
  237.56 [INFO]:nasal     :16: Cargo=0  cargo1
  241.52 [INFO]:terrain   C:\Jenkins\workspace\Windows-release\flightgear\src\Scenery\scenery.cxx:85: Got ground pick at lon = 18.3466deg, lat = 57.6685deg, elev = 41.4029m
  243.76 [INFO]:terrain   C:\Jenkins\workspace\Windows-release\flightgear\src\Scenery\scenery.cxx:85: Got ground pick at lon = 18.3461deg, lat = 57.6685deg, elev = 41.0286m
  246.20 [INFO]:nasal     :16: Cargo=1  cargo2
  247.64 [INFO]:terrain   C:\Jenkins\workspace\Windows-release\flightgear\src\Scenery\scenery.cxx:85: Got ground pick at lon = 18.3459deg, lat = 57.6685deg, elev = 40.8979m
  249.04 [INFO]:terrain   C:\Jenkins\workspace\Windows-release\flightgear\src\Scenery\scenery.cxx:85: Got ground pick at lon = 18.3459deg, lat = 57.6685deg, elev = 40.9033m


I am running FlightGear 2020.3.4 on Win 10, and having the addon as a shallow clone of the GitHub repo with HEAD at commit dac896 from Mon, Mar 1, 2021.

[wlbragg]

Those must be fairly new to the FGUK hanger? I thought I has most of them in the addon. If you come across any aircraft you think should be in there, you can forward them to me and I will add them to the addon repository.

Did you have those errors before you made the new entry?

I'm almost there with the bambi bucket logic. It has required many iterations of logic changes and brain storming to whittle it down to something generic that can be used over a wide range of aircraft.

I haven't got the effects sorted out yet though, but I think I am getting close. I'm just finishing up the logic to load the bucket with water and dump the bucket. Adding the bucket it to the addon was simple.

If anyone has any GPL bambi buckets of different sizes, now would be a good time to point me to them so I can incorporate them in the addon.
If not I may eventually make the bucket sizeable using the scale animation. Of course I would also increase the weights.

I am surprised that even with my not so perfect helicopter skills I can feel when I have a load attached.

If your talking about the bambi bucket, it only is adding 106 lbs without water. When I am finished with the logic it will add 2006 more lbs of water. That is the 910 liters bucket. You might check my math!

In the meantime You can artificially add the 2006 simulated weight to the bambi bucket in the Cargo Towing GUI, select bambi bucket and at the bottom of the screen under weight, change it from the 106 to 2112. That should at leas give you the simulated full load.

I'll worry about the errors you have once I am finished with my current round of coding and push it to the addon. Hopefully in the next hour or so. As soon as I get the retardant loading and unloading, I'll push that. Then start work on the effects and the tie in to wildfire.

[wlbragg]

Ok, that was a real test of patience. It took me a couple of hours to track down the simplest of issues, catching whether the ground is solid or water and displaying the results in the "On-screen displays" helper I sometime use when I have complex code and need to watch variables. I already had the code in place for other areas of the logic, but when I tried to add it to the debug "On-screen displays" in order to watch the flow of the code, it kept throwing an error. So you either can't add a "true" bool to the "On-screen displays" framework, or I am just stupid!
It works fine in an if statement but in order to see the value of that particular variable in the "On-screen displays" framework I had to do it indirectly using an if statement to set it.

Long story short. to set the debug screen helper "over-land" I had to do it with the following...

Code: Select all

if (overLand.getValue())
   setprop("over-land", 1);
else
   setprop("over-land", 0);

Instead of how I set all the other variables I am watching which should work like this...

Code: Select all

setprop("over-land", overLand.getValue());

I was forced into this logic and I don't like to be forced into anything, especially when I don't understand it why.

Next up, particle drop animation and animations for the bucket hitting the water and maybe even water in the bucket when full, retardant handoff to wildfire.

EDIT: Oh, use the e key to release the water load. Just dunking it in a lake or river will fill it.
I'm aware of the existing particle effect being in the wrong position and color, also that the retardant isn't tied to wildfire yet. So no retardant models.

[wlbragg]

This just isn't coming easy. I have the particle effect for the water drop mostly working, but I am having a difficult time getting it positioned perfectly and it changes slightly every time the bucket changes from the placed model back to the submodel.

I pushed what I have so far. I may take a break and work on the wildfire retardant model portion for awhile.

[Johan G]

Some more posts were moved here from the topic Caldor Fire: Water Bombers, Helos, Pathfiders, Oh My! 9/. Quote added for context.

Will show up in the FGUK MD500E and try out the (smaller) bambi bucket of the wlbragg's cargo towing addon

I have added the MD500E with these lines in Cargo-Towing-Addon/Aircraft.xml (if using coordinates from the FDM, the cable turns up neatly coiled on the cockpit floor ):

Code: Select all

    <aircraft n="31">
        <!-- weight x="0.5" y="0" z="1.2" mass-prop="/sim/weight[1]/weight-lb"/ -->
        <name type="string">500e</name>
        <x-pos type="double">1.75</x-pos>
        <y-pos type="double">0.0</y-pos>
        <z-pos type="double">0.325</z-pos>
        <offset type="double">3.75</offset>
        <diameter type="double">0.75</diameter>
        <wincharm type="int">0</wincharm>
        <loadpoint type="int">1</loadpoint>
    </aircraft>


Besides adding the anchor point for the weight in the FDM what do you have to add to the menu choices in the ***-set file?

I have both the AeroSpatiale 315 Lama and the AW139 already set with cargo weight inside the cabin.

[LesterBoffo]

Here's some long-line hovering with a AS315 Lama.