Vehicle Maker Confusion and Confustication!

[david.wendelken]

I will work on it then.

All, to add to your fuel possibilities, you might want to take a look at "blau gas" which was used by the Graf Zeppelin. The following quote is from Wikipedia.



Also, the USS Akron and Macon both had condensing units for the engine exhaust which condensed sufficient water from the exhaust to compensate for the weight of the burned fuel. The British in WW2 used a similar device in the Western Desert to condense water from engine exhaust in order to reduce the water consumption of units. The water condensed is not readily potable, but could be used as radiator water for desert vehicles.

I had run across both those while reading about the Hindenburg.

I decided to go with a modern fusion drive. It would be cheaper to import a few of those and the tools to maintain them than explore and drill for oil and build a refinery...

Plus, if you're trying to upgrade a planet's technology level whilst maintaining its near-pristine natural beauty, skipping over dirty coal/oil/gasoline powered industry is a good way to start.

 

[Timerover51]

I had run across both those while reading about the Hindenburg.

I decided to go with a modern fusion drive. It would be cheaper to import a few of those and the tools to maintain them than explore and drill for oil and build a refinery...

Plus, if you're trying to upgrade a planet's technology level whilst maintaining its near-pristine natural beauty, skipping over dirty coal/oil/gasoline powered industry is a good way to start.

The way I am handling it on a colony planet is to use a fusion plant to hydrolyze water for the hydrogen, and react the hydrogen with local carbon dioxide with a catalyst to produce methane gas. The methane gas is then converted into synthetic oil for use as fuel. No additional carbon is added to the atmosphere. The production plants do need to be sited near large bodies of water.

On another planet, there are no fossil fuel deposits, only surface peat accumulations. The local populace has no problems with limited imports of liquid fuels. They would rather use the alcohol that they can refine for other purposes.

 

[david.wendelken]

The way I am handling it on a colony planet is to use a fusion plant to hydrolyze water for the hydrogen, and react the hydrogen with local carbon dioxide with a catalyst to produce methane gas. The methane gas is then converted into synthetic oil for use as fuel. No additional carbon is added to the atmosphere. The production plants do need to be sited near large bodies of water.

On another planet, there are no fossil fuel deposits, only surface peat accumulations. The local populace has no problems with limited imports of liquid fuels. They would rather use the alcohol that they can refine for other purposes.

Interesting. If I wanted to use hydrogen gas, one option would be to buy the bulk unrefined liquid hydrogen from the local Class B starport on planet. It would only take about 1400 tons of liquid hydrogen to make 14,000 tons of gaseous hydrogen (the gas volume of the Hindenburg). Couldn't find the unrefined fuel cost in the T5 rulebook. Is it CR 100/ton? That would make a full gas load for a Hindenburg sized vehicle around CR 140,000.

 

[Reban]

Fuel Benchmarks p.360 says under Liquid Hydrogen "raw (or unrefined) fuel is available for about 100Cr per ton. Pure, (or refined) fuel, properly filtered and certified for powerplant use is available for 500Cr per ton".


Note that it says "about 100Cr" so you could negotiate a better (or worse) rate depending on the source. Raw also means anything from ice, to water, to atmospheric hydrogen. How refined would it need to be for a lifting gas? Probably not as refined as PPlant fuel.

 

[david.wendelken]

(Sorry, I don't understand what I've done wrong with the table layout. I'll be glad to edit it if someone gives me a hint...)

I went over the T5 rules for LTA vehicles and basically concluded that the Hindenburg, a real-life airship, could never have been built.

Then again, aerodynamic engineers swear bumblebees can't fly and yet they do...

So, here's my take on a TL6 LTA Airship manuevered by electric engines powered by a standard Fusion+ powerplant unit.

All Ton Measurements in LH volume Tons unless otherwise noted.
TL 6 Construction-capable unless otherwise noted.

Item	Size	Notes
Gas Bag	14,218	Helium-filled, Hindenburg 14,124
Cupola	1,579	Aluminum or Titanium construction
Passenger Cabin, 1st Class	240	60 passengers @ 4T
Passenger Cabin, 2nd Class	312	156 passengers @ 2T
Captain's Cabin	6	.
Head Steward's Cabin	4	.
Flight Crew Cabins	38	19 crew @ 2T
Steward Crew Cabins	58	29 @ 2T, includes 2 Medics
Ship's Stores	33	.2 T per 1st Passenger, Captain, Head Steward, .1 T per 2nd Passenger, Flight and Steward Crew
Mail	1	.
Cargo	100	.
Cargo Lift Plate Compartment	20	Grav lift plates are not installed, but the ability to add them is present. This would enable heavier cargo to be carried or possibly to be used to replace the need for ballast. Currently used for Cargo.
Ballast	100	Can be easily converted to cargo space if lift plates installed.
Powerplant, Engines	30	Standard Fusion+ powerplant, electric engines.
Galley	20	.
Common Areas	708	Passengers & Crew @ 3T
Option	.	Protected
Option	.	Wilderness Landing
Option	.	AutoPilot, Powered Controls
Speed	76Kph	.
Duration	7 days	.
Range	13440K	.

The Hindenburg had a huge allotment for fuel and oil - over 30% of its weight allotment went to those two categories. A standard Fusion+ module saves a huge amount of weight and space.

57% of the Hindenburg's weight went to the rigid airframe, engines, etc. Electric engines are smaller and lighter than diesel/gasoline engines, plus more reliable. The actual fuel tanks wouldn't be needed either. Key structural elements made out of titanium instead of steel or aluminum should also reduce the weight. Plus, of course, several thousand years worth of metallurgical and structural engineering knowledge can be applied to further reduce the weight.

I haven't worked out cost yet.

 

[david.wendelken]

My best guess for the above airship would be circa CR 10,000,000, or CR 8,000,000 in production mode.

The wilderness landing capability is based upon the special capabilities of its Larianz crew members, who can easily glide down to the ground and secure the vessel with ropes and stakes.

On the grasslands, the human and vargr passengers can debark or embark via an extensible staircase to the ground.

In wooded or irregular terrain, passengers use motor-driven slings to debark and embark.

Because the airship cannot remain tethered if the winds pick up, and embarking passengers quickly enough may endanger the ship, a portable shelter unit containing necessary supplies is always off-loaded before any passengers debark. (The Larianz, though they do not fly per se, can still use their wings to clamber up the landing ropes very quickly.)

This airship does not replace bulk cargo carriers, particularly bulk grain barges and cargo ships. It does allow for cargo delivery in the outback in sufficient quantities to support homesteader villages and wilderness tourism activities in the absence of a road or navigable river network.

 

[david.wendelken]

As this discussion started off involving balloons and airships, I do have the Tentative Table of Organization and Equipment for US Army balloon and airship units as of 1925. Would anyone be interested in my converting them into something a bit more readable and posting them?

Just a friendly reminder...

 

[Timerover51]

Just a friendly reminder...

Okay, I will work on it this week. The Airship used for the Tables is the US Navy Shenandoah airship. Unfortunately, it does not give detailed crew tasks tables. I will have to see what I can find on that.

 

[atpollard]

From reading, I always had the impression that Rigid Airships tended to be over-crewed. I think it had to do with a shortage of airships and a desire to train crews for wartime.

Purely speculation, but I think that a ship like the Hindenburg could operate on half its historic crew levels on a world where airships were common.

 

[Timerover51]

From reading, I always had the impression that Rigid Airships tended to be over-crewed. I think it had to do with a shortage of airships and a desire to train crews for wartime.

Purely speculation, but I think that a ship like the Hindenburg could operate on half its historic crew levels on a world where airships were common.

I believe that might be the case. I have the crewing data, at least size of crew, for the USS Shenandoah, and if I remember correctly, they carried a mechanic for each motor, and had both a trimsman and a helmsman for airship control.

David, I have the data for the airship organization printed out and I will convert it into a PDF table for you. I am not that great with the Table layout here as yet, so I might need help getting it posted here. Also have the characteristics for the Shenandoah to include as well.

 

[david.wendelken]

Great!

I'm also PM'ing you with my email address, so you can send it to me directly, if that will help. I'll be glad to reformat it.

 

[Timerover51]

Great!

I'm also PM'ing you with my email address, so you can send it to me directly, if that will help. I'll be glad to reformat it.

I have not forgotten, just that this Christmas season has been a bit hectic. As for giving you some idea of cost, in the Journal of the Traveller Aid Society number 2, in the Ships Locker section, it gives a description and a cost for a semi-rigid airship, Tech Level 7. Size is 70 meters long, 30 meters in diameter, with a volume of 45,000 cubic meters, and it is powered by fuel cells. The cost given is 500,000 Imperial Credits.

 

[david.wendelken]

Thanks for the tip on the JTAS article. I had forgotten that one!

The Hindenburg had a gas bag about 16 times the size of the airship featured in JTAS#2.

I guess I didn't do that badly on the estimated cost as I proposed CR 8,000,000 once in production mode, which is 16 times that cost...

Some things would be more expensive because the ship was bigger, others would be cheaper (per unit) due to economies of scale. I'll just treat it as a wash.

 

[Timerover51]

You would have much more internal structure, as the airship in the JTAS article is basically a blimp, with very little internal structure, as Victoria is a metal-poor world. You might want to bump it up maybe 25% or so, but that is your call.

I am probably going to be going through the various design processes in T5 in the next week or so.

 

[david.wendelken]

You would have much more internal structure, as the airship in the JTAS article is basically a blimp, with very little internal structure, as Victoria is a metal-poor world. You might want to bump it up maybe 25% or so, but that is your call.

I am probably going to be going through the various design processes in T5 in the next week or so.

Fair enough, but I realized I had made a math error when comparing the relative sizes. The JTAS article airship is almost 1/5th the size of the one I'm designing, not 16th. So, mine might actually be too expensive, but I'll leave it at that price range as it's supposed to be a luxury passenger vehicle, not a cargo hauler.

 

[david.wendelken]

This is a great site about airships. The graphic on the linked page clearly shows how huge the Hindenburg was compared to modern passenger jets.

 

[Draconian]

Vacuum+stasis-field blimps

Here's a wild idea for you. In the RINGWORLD RPG (Chaosium), high-tech worlds made a high-tech Zeppelin by activating an oval stasis-field in space. It would trap vacuum and be a totally rigid impenetrable football-shape with no "give". Then they tethered it to the surface of a planet and brought it down. The buoyancy was always equal to the total weight of displaced air-volume, not the difference between a light gas and normal air.

Hydrogen lifts 1.202 kg per cubic meter. Helium does almost as much at 1.114 kg per cubic meter. However, a vacuum trapped in stasis does the full shot of the weight based on the density of air minus the density of vacuum (zero!) Overall a vacuum stasis-field can be made only slightly smaller than the balloon made from a gas, pulling the same weight.

The only problem is, you can't regulate the volume of a vacuum trapped in stasis to control your altitude. It's always the same volume and so the same "pull". You have to regulate with other means. For example, over 150 years ago Edgar Allen Poe gave the solution. He said put the blimp over water and hang floating rope trailing down into the sea. If the balloon should rise, it pulls up more rope above the waterline so more weight is added to keep it from flying up forever. If, however the balloon should fall, more rope falls into the sea and floats, lightening the total weight and bringing the balloon to an equilibrium altitude. Use the rope as easily-accessed mooring when you get to your destination.

Or, have some companion-balloons of regular gas, which can be regulated by filling more gas in a balloon or recompressing it.

In the rulebook they said the stasis-field's batteries were very high-yield Puppeteer designs, but were expected to discharge after about 50 years, at which point a balloon in the sky would be completely lost, with an implosion-bang, and the gondola would plummet to the ground.

 

[david.wendelken]

Here's a wild idea for you. In the RINGWORLD RPG (Chaosium), high-tech worlds made a high-tech Zeppelin by activating an oval stasis-field in space. It would trap vacuum and be a totally rigid impenetrable football-shape with no "give". Then they tethered it to the surface of a planet and brought it down. The buoyancy was always equal to the total weight of displaced air-volume, not the difference between a light gas and normal air.

That's an interesting idea. Black Globe generators at TL 16 are effectively stasis fields, are they not? I might have to develop a prototype device that would do that, just for fun. Or re-purpose the Kinunir's....

 

[Timerover51]

In the MegaTraveller COACC book, a rigid airship has a base cost of ICr50,000 per thousand cubic meters of ship.

You might want to take a look at that as well, if you have it or can get access to it. You can download if from Drive Thru.

 

[Licheking]

Brilliant book, i converted all the aircraft to T5.