Pirates Without Borders

Pirates Without Borders => Build the Ship => Design => Topic started by: cameron on November 28, 2017, 12:29:37 PM

Title: Cargo Design
Post by: cameron on November 28, 2017, 12:29:37 PM
Have been trying to detach the cargo hold from the ship, so the ship can easily drop and pickup new cargo. Still need to figure out ship weight vs. cargo weight. If it's 50/50. Based on lifting capacity, that's about 500 tons of cargo, and 500 tons for the ship.

Does anyone have ideas how the cargo hold would attach/detach? Locating pins? Docking collar? Ropes & chains? Magnets?

Keep in mind that the mating surface is over 600' long. If the ship were to land and pickup a cargo pod, trying to get it aligned would be a monumental task. Even though the ship is lighter than air, adjusting a floating 500 ton ship would be hard to move around to dock with the cargo docking collar.

And once it's located, how does it "lift" 500 tons of cargo without tearing the ship and/or cargo hold apart? How does the mating surface hold 500 tons to the ship? For example, if they were bolted together, those "bolts" would have to lift and hold 500 tons while in flight (plus any g-forces created by acceleration).

Title: Re: Cargo Design
Post by: cameron on November 28, 2017, 06:48:28 PM
How large does the cargo hold need to be? It's currently 2.3 million cu.ft. If cargo capacity is 500 tons, that's 0.43lbs per cubic foot. Seems like there's too much available space if 1 cu.ft. can only "carry" 0.43lbs.

1 cu.ft. of water weighs 63lbs.

1 cu.ft. of steel weighs 490lbs.

1 cu.ft. of gold weighs 1206lbs.

1 cu.ft. of marshmallows (http://https) weighs 13lbs? (search "Candies, marshmallows")

To use an Ernie-ism... "Get my point?" If you filled the cargo hold with marshmallows, it would weigh 14,950 tons!

If you're mainly transporting 40' shipping containers, they can weigh up to 30 tons each. http://www.dsv.com/sea-freight/sea-container-description/dry-container A 500 ton cargo hold could only carry 16 fully loaded containers, or 38,244 cu.ft. of cargo.

Is a 2.3 million cu.ft. cargo hold extreme overkill? Or is my math completely wrong?
Title: Re: Cargo Design
Post by: Ernest Hancock on November 29, 2017, 02:19:04 PM
Good points.

The ability to drop Shipping containers through the floor from cables without even landing would be nice.

But one option would be that the removable pods would be homes/factories/emergency shelters/command posts etc.
Title: Re: Cargo Design
Post by: Ernest Hancock on November 29, 2017, 02:22:46 PM

The cover of this issue of the eZine was about this very concept of building a town in the outback via dropping off completed homes.
Title: Re: Cargo Design
Post by: Eduardo Blomar 1679 on November 30, 2017, 06:49:28 AM
My Good Fellow Pirates,

In consideration of receiving/delivering cargo in a Lighter Than Air Vehicle you must remember ballast displacement equal to the cargo for attaining liftoff weight.

I agree with Ernie and add that steel cable should sufficient for standard containers.

Eduardo Blomar 1679
Title: Re: Cargo Design
Post by: cameron on December 08, 2017, 07:12:02 PM
Steel cables seem to be the leading solution. So it could evolve into external cargo like the aeroscraft design. http://aeroscraft.com/fleet-copy/4580475518

I was hoping for something more rigid that would "dock" with the ship. That way you could have an airlock between the cargo and the ship. If you wanted a flying indoor driving range, people could move to the cargo hold while in flight. Still working on redesigning the arch to make this possible.

I posted a .blend file of the basic cargo "tub" (http://http) if anyone wants to play with designing your own cargo module in Blender (http://https). There could be a module that can drop shipping containers with steel cable, another could have doors and cranes to load/unload shipping containers, another could be a mobile medical facility, or the interior of your flying house.

Still trying to figure out how these different cargo holds will attach to the ship, so the design could always change. Or the entire thing could change (shrink?) based on how much space is truly needed.

Currently, the inner "envelope" is just over 2.3 million cu.ft. Roughly 500' long, 125' wide, and 74' tall. The very bottom is 14,400 sq.ft. and 50' up is roughly 40,500 sq.ft.

I still think the volume is too big for the amount of weight it can hold. 0.43lbs per cubic foot isn't much cargo. I think the cargo ships (in the ocean) average 100lbs per cu.ft. making the cargo hold smaller could give more space for the lifting envelope (i.e. more weight capacity).

Of course this is all based on a 500ton capacity (1/2 of total lifting capacity). We still don't know what the rest of the ship will weigh.
Title: Re: Cargo Design
Post by: Ernest Hancock on December 14, 2017, 02:15:42 PM
I just saw this post and the page you created. My direct email is Publisher@FreedomsPhoenix.com for this sort of stuff so I can communicate to the wider audience of FreedomsPhoenix and the Radio Audience.

Sorry that I just saw this.


I just posted the info at the top of FreedomsPhoenix and it'll get out to the subscribers by tonight in the next Email Dispatch. I went into the forums to see what you were working on and saw that you have been busy. Sorry for the delay.

I'll pump for you getting some Holiday Crypto on the show too.

Great Work!



Title: Re: Cargo Design
Post by: cameron on December 14, 2017, 05:11:48 PM
Thanks Ernie. I'll try to let you know via email for major updates.

I setup precariat.us.to (http://http) so I can eventually post files larger than the 200K limit here on the forums. Posted some STL files (http://http) and the cargo hold (http://http) to get people started.

Have been reworking the ship to have the detachable cargo hold, added more lift capacity, and greater living space in the lower levels. Still working out the details.

Also worked on the ion drives in the tail. Thinking about doing the same to the bottom of the ducted fans, but at the same time I worry about crossing over into SCI-FI. I think the ship should stay realistic & practical (with bleeding edge technology). So no laser guns, photon torpedoes, or warp drive : )

Still trying to figure out how they should look.

All this required structural changes to the ship's mesh. Had to rebuild the bottom of the ship and the tail (there are still parts that are "carved out", that need fixing). Still trying to clean up the model.
Title: Re: Cargo Design
Post by: cameron on January 17, 2018, 07:06:13 PM
Have been reworking the cargo hold. Released a new model at http://precariat.us.to/cargohold (please donate! (http://"http)). This cargo hold is the smaller size that fits version 3 of the Precariat (http://"https).

Have been trying to figure out how to dock with the cargo hold in 3D space (including yaw, pitch, and roll). Haven't been able to come up with anything hi-tech. I suppose a laser guided automatic docking system can take control of the ship and perfectly align it to the cargo hold in any position under any weather conditions. But someone else will have to design it : )

Trying to be practical, all I could come up with is using mooring lines and winches to "pull" the ship into place (the same as ocean ships). The Precariat would float close to the cargo hold, then drop lines to connect at various points.


With the mooring lines connected, the cargo hold (or the ship) could winch itself into position. Once in position, the ship & cargo hold would "lock" together. The bottom of the ship contains a grid of I-beams that are integrated into the ship's structure.


Need a structural engineer to do the math, but the largest I-Beam I could find was 24" that weighs ~120lbs per foot. I'm not sure how many beams you would need to lift 500 tons, but made a grid of beams totaling 1786 feet. Which added 107 tons of weight to the ship(!!!). I couldn't find any graphene I-beams. Can someone calculate how much a beam can "lift" per span (ten 95' spans shown) and how many are needed to lift a fully loaded cargo hold?

For the locking mechanism, all I could think was to grab onto the i-beams. Once winched into place, the cargo hold would literally "grab" the ship and hold on (watch yellow clamps at the top of the image).


Hopefully detaching the cargo will be much easier. Just disconnect and float away (after adjusting lift/ballast to compensate for losing the cargo weight).

Title: Re: Cargo Design
Post by: Eduardo Blomar 1679 on January 18, 2018, 09:42:07 AM
Are we married to using maritime/land based containers? There seems to be a large assortment of Air Cargo containers that weigh considerably less:


Also, how about a non-detachable area that the cargo loads into via a port (one container at a time) that, when empty, can be filled with gasbags for additional lift?

Title: Re: Cargo Design
Post by: Eduardo Blomar 1679 on January 18, 2018, 11:07:23 AM
Here are some specifications from Granger Aerospace for you:


Title: Re: Cargo Design
Post by: cameron on January 18, 2018, 11:27:28 AM
The cargo hold could carry anything. I just used shipping containers to show scale (using something familiar). The entire cargo hold would be a sort of "pod" that you could fill with whatever you like. Different "pods" could be designed to carry anything. Just trying to come up with a docking system that would be universal to all "pods".

There's a freight elevator (http://"https) for other parts of the ship (non-cargo). Gasbags could be loaded that way if necessary. I was also wondering if you could flood the cargo hold with helium/hydrogen to displace any air in the cargo hold and provide extra lift. Though it would probably kill any live cargo in the cargo hold.

Which is another option... If your cargo needs life support, the cargo hold would have to be designed to provide it. The different designs of cargo holds are endless. I was just trying to figure out how they would all be lifted by the Precariat.
Title: Re: Cargo Design
Post by: cameron on April 08, 2018, 02:28:20 PM
Came up with another style of "cargo" that uses the Precariat as an air launch system (http://https) for satellites.

There are a total of 52 launch tubes to launch several types of payloads. The Precariat would lift to 100km, then each tube could launch it's own stage 2 rocket to take it's payload to it's final altitude & orbit.

There are 33 small (5' dia. / 72' long) launch tubes for rockets with smaller cube-sat style payloads like Vector-R/H (http://https) & Falcon 1 (http://https).

16 medium (17' dia. / 72' long) launch tubes for Falcon 9 (http://https) style payloads. And 3 large (26' dia. / 448' long) launch tubes for something much larger.

Rockets would be launched from the "cargo hold" with cold-gas thrusters, then ignite their main thrusters once clear of the ship.

The Precariat replaces the conventional stage 1 of a rocket launch system. The rockets that launch from the ship only need enough power to achieve orbital velocity and lift the payload to it's final altitude.

Was going to make an animation to show the process, but it will take forever (please donate! (http://http)).


Title: Re: Cargo Design
Post by: cameron on April 08, 2018, 02:29:12 PM
Title: Re: Cargo Design
Post by: cameron on May 06, 2018, 07:31:55 AM
Uploaded both cargo designs to Sketchfab (http://https) so you can view, rotate, zoom & explore the model in your browser.

[attachment=1]Untitled1.jpg[/attachment] (http://https)

[attachment=0]Untitled2.jpg[/attachment] (http://https)