Life & Temperatures on Titan

[DataPacRat]

Originally Posted by Anthony

Anything that involves polymers isn't a great plan. The basic requirements are that the outer layer has to be able to handle cryogenic temperatures, and the R-value has to be sufficient to not freeze. This isn't all that demanding, your average dewar flask can do both (though it's not durable enough without more tech), but it's almost certainly going to have to be a hardsuit.

If the point you're suggesting is to imitate a dewar by having some vacuum between inner and outer layers, why not handwave/technobabble something about the hard-scales actually just all being tiny little vacuum-filled thermos-like insulators themselves? (Or, for somewhat more plausibility, high-TL aerogels filled with vacuum instead of air?) The suits' DR would really just be a side-effect of having materials tough enough to withstand the pressure differentials.

As another thought, if the tech for flexible insulators good enough for walking around in Titan exists, and is on the order of $600 for a human's surface area, can anyone think of interesting alternate uses for it? Better fridges and hot-water tanks at home? Something something industrial processes? Laptops that run ridiculously hot internally without singeing their users?

[Anthony]

Originally Posted by DataPacRat

If the point you're suggesting is to imitate a dewar by having some vacuum between inner and outer layers, why not handwave/technobabble something about the hard-scales actually just all being tiny little vacuum-filled thermos-like insulators themselves?

Making scales that prevent heat passing through them isn't too hard. The problem is heat passing around them. Simple scales (as found in scaled armor, brigandine, etc) are not sealed at all. You can join the scales with a flexible material (if one exists), or with various types of sliding or hinged hard constructs, but all such joins are problematic -- they're a weak point, they're hard to insulate, they're hard to seal, they're a point of failure. Thus, it's easiest to use as few joins as possible -- which gives you a hard suit.

[DataPacRat]

Originally Posted by Anthony

Making scales that prevent heat passing through them isn't too hard. The problem is heat passing around them. Simple scales (as found in scaled armor, brigandine, etc) are not sealed at all. You can join the scales with a flexible material (if one exists), or with various types of sliding or hinged hard constructs, but all such joins are problematic -- they're a weak point, they're hard to insulate, they're hard to seal, they're a point of failure. Thus, it's easiest to use as few joins as possible -- which gives you a hard suit.

I'm realizing that I've been conflating two use-cases, and differentiating between them may resolve our apparent disagreements.

Case One: A well-prepared person goes on a walk outside. Goal: Stay well-insulated for hours or even days. Likely method: Hardsuit, as you suggest. This one is fairly easy to build in GURPS, if any of the standard ultratech suits don't quite fit.

Case Two: A regular person is living inside a Titanian dome. Goal: If something happens to their dome (or vehicle, or airlock, or whatever), avoid falling unconscious in 20 seconds and dropping dead 20 seconds after that; eg, fifteen minutes of protection to get to a better suit (though longer would be even better). Method: Something that can be worn all day, every day, possibly under other clothing. This is the tricky one to build well, and is the one I've been trying to ask for suggestions about.



(Also, Pulver's armour system has a few other options for rigid materials; Scales (small linked platelets), Segmented Plate (large, overlapping bands), Plate (carefully shaped), Impact-Absorbing (plate, but padded or collapses when hit), and Solid (flat plates, not suitable for limbs). But other than innately flexible materials, only scales count as bendy enough for the 'can it count as clothing?' rules.)

[Anthony]

Originally Posted by DataPacRat

Case Two: A regular person is living inside a Titanian dome. Goal: If something happens to their dome (or vehicle, or airlock, or whatever), avoid falling unconscious in 20 seconds and dropping dead 20 seconds after that

Ordinary clothing most likely; any disaster of sufficient magnitude that the local atmosphere gets instantly replaced will be directly fatal before the atmosphere much matters and will likely set off an explosion, since oxygen will react with Titan's atmosphere.

[DataPacRat]

Originally Posted by Anthony

Ordinary clothing most likely; any disaster of sufficient magnitude that the local atmosphere gets instantly replaced will be directly fatal before the atmosphere much matters and will likely set off an explosion, since oxygen will react with Titan's atmosphere.

So, what you're saying is that the current Titanian fad for wearing these outfits is something like 2020-era EDCers with their multitools, flashlights, pill holders, and other almost-never-used gadgetry? :)

[Anthony]

Originally Posted by DataPacRat

So, what you're saying is that the current Titanian fad for wearing these outfits is something like 2020-era EDCers with their multitools, flashlights, pill holders, and other almost-never-used gadgetry? :)

That seems fair, yes. In any case, soft would be fine; sure, it will probably crack and be destroyed if used at low temperatures for an extended period, but it's fine for emergency systems to be disposable.

[AlexanderHowl]

A rescue bubble would probably be a better idea, though it would need extra air pressure to counter the Titan air pressure. Since it is flexible enough to move around in, people could get to safety before they would freeze to death (fifteen minutes since they would not be directly exposed to the cryogenic environment). At 3 lbs and $600, I imagine that everyone would carry one, as it could mean the difference between life and death.

[DataPacRat]

Originally Posted by AlexanderHowl

A rescue bubble would probably be a better idea, though it would need extra air pressure to counter the Titan air pressure. Since it is flexible enough to move around in, people could get to safety before they would freeze to death (fifteen minutes since they would not be directly exposed to the cryogenic environment). At 3 lbs and $600, I imagine that everyone would carry one, as it could mean the difference between life and death.

That's pretty close to the weight and price-point of the original suit design.

My latest notes: The current fad is for shiny black heatsuits; a few years ago, the style was something more resembling lingerie; before that, transparent; before that, instead of being worn, they were stuffed into auto-deploying fanny-packs; before that, carried by little robots, which themselves were a development of the whole artificial shoulder-dragon fad...

[Fred Brackin]

Originally Posted by DataPacRat

I

Anyone have stats for Titanian strap-on wings? Or do I need to dig into 3e Vehicles' for, say, a muscle-powered engine, ornithopter drivetrain, and strap-on harness crew station?

Sorry, the closest my memory says we got was when i suggested something like the Helipack from UT p.230. The idea was to have some James bond-like chase scenes.

I suspect that there are some strap-on wings somewhere. 3e had a Skill for using them.They might not be very scientifically rigouous though.

[DataPacRat]

Originally Posted by Fred Brackin

Sorry, the closest my memory says we got was when i suggested something like the Helipack from UT p.230. The idea was to have some James bond-like chase scenes.

I suspect that there are some strap-on wings somewhere. 3e had a Skill for using them.They might not be very scientifically rigouous though.

Welp, here's a first draft of a Titanian wing-set. I just kept fiddling until top speed was above stall speed, and the lowest stall-speed was something a PC could run at... so I'm sure there's all sorts of ways to improve the design. For example, I probably really should put in that vehicular parachute, in case the pilot stops trying to even just glide. And I'm not really sure about a typical, ST 10-ish PC getting full performance out of that muscle-engine. And better performance might result if I abandoned the 'flap your arms' approach and hooked up the muscle-engine to a ducted fan. But I'm finally feeling too sleepy to recalculate everything, so I'll have to put that off for a while. (Feel free to suggest alternate designs. :) )

--

Titanian Strap-On Wings, Mark One:

* Overall:
- TL10
- Streamlining: Fair
* Body: 0.22 cf, 2.186 sf, 0.3279->1 HP
- Maneuver Controls, Mechanical
- Crew Station, Harness: 2 lbs, 0 cf, $25
- Pilot: 200 lbs
- Muscle Engine (up to ST 20), 0.4 kW: 4 lbs, 0.2 cf, $20
* Wings, STOL: 0.125 cf each, 3 sf each, 0.45->1 HP each
- Ornithopter Drivetrain, 0.4 kW: 1.2 lbs, 0.024 cf (0.012 cf per wing), $120, motive thrust 0.8 lbs, lift 2 lbs
- Access space: 0.012 cf each wing
- Empty space: 0.101 cf each wing
* Structure: 8.186 sf, 0.47 cf, SM-2
- Super-Light, Very Cheap Materials, Responsive, Winged: 3.2744 lbs, $147.35
- Folding Wings: 0.12 lbs, $3
- Variable-Sweep Wings, Manual: 0.24 lbs, $22.50
* Surface:
- Armor: Flexible, DR 1, 8.186 sf: 0.16372 lbs, $16.37
* Price: $354.22
- Maintenance: 4h every 1,062 hours of flight (44 days)
* Loaded Weight: 210.99812 lbs
* Health: 6

* Performance:
- Stall Speed (Earth): 50 mph [VX2 formula]
- Stall Speed (Titan): 15 mph
- Stall Speed (Titan, out-swept wings): 7.5 mph
- aDrag: 23.4108333
- aSpeed: 16 mph
- aSpeed (out-swept wings): 8 mph
- aAccel: 0.076 mph/s (99 seconds to accelerate 7.5 mph)
- aMR: 3 Gs
- aSR: 3
- aDecel: 12 mph/s
- Ceiling (Earth): 516 yards / 0.29 miles
- Ceiling (Titan): 3,587 yards / 2 miles
* Performance, gliding:
- Terminal velocity (Earth): 260 mph
- Top glide speed (Earth): 104 mph
- Glide ratio (Earth): 4.32
- Glide ratio (Earth, out-swept wings): 17.3
- Glide from ceiling (Earth): 8,926 yards / 5 miles
- Terminal velocity (Titan): 79.4 mph
- Top glide speed (Titan): 31.75 mph
- Glide ratio (Titan): 4.48
- Glide ratio (Titan, out-swept wings): 17.92
- Glide from ceiling (Titan): 64,279 yards / 36.5 miles (up to 2h26m)

* Notes:
- Skill: Piloting (Ultralight)
- Fatigue (from piloting): 1 FP / hour, x2 if under 500 feet
- Fatigue (from muscle engine): 1 FP / hour (more if encumbered)
- G-forces at 16 mph: 90° bend: 1.2 Gs. Up to 225°/second without exceeding MR; 1.6 seconds to turn 360°, a circle 12.5 yards in circumference or 2 yards in diameter
- Deceleration from climbing (Titan): 35% forward movement dedicated to climb: -0.966 mph. (Can dedicate 2.75% of forward speed to climbing, and still accelerate enough to maintain constant speed. At 16 mph / 8 yards/sec, that's a climb rate of 0.22 yards per second, 13.2 yards per minute, 792 yards per hour; 11.2 hours to climb to ceiling.)
- Acceleration from diving (Titan): 50% dive: +1.38 mph. 100% dive: +2.76 mph. (6 seconds to go from halted to stall speed, during full dive, taking around 25 yards of falling; jumping off an 8-story building should be safe enough.)

? Vehicular Parachute, rated 250 lbs: 2.5 lbs, 0.1 cf, $25. (Half in each wing?)

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