Extra Crispy | 18 Jun 2015 6:37 p.m. PST |
In the background to my VSF Skyships! game, the tech to get the antigravity effect puts a severe limit on weight that can get airborne. As a result fuel and ammo are at a premium. You have to balance the wight of guns, fuel and ammo against lift capacity. Since fuel is heavy, my thought is during peace time such ships might actually employ sails. Wind after all is free, and masts and canvas while heavy, don't get exhausted like coal/fuel oil. Why not just land and refuel? There simply aren't suitable landing fields with the necessary booms, supplies, etc. to resupply a flying navy ship. You can shuttle from base to base but that leaves little or no time for fighting and maneuvering. So I was thinking wind would come back into vogue – especially for merchantment, pleasure craft, etc. What do you think of the idea? |
Parzival | 18 Jun 2015 7:02 p.m. PST |
Space: 1889 introduced the Martian "kites," so why not? What you need, of course, is the suitable argument for a "keel." I suggest that it be a nice handwavium effect of anti-gravity tech that helps keep a craft stable and resistant to lateral movement by winds. If that is the case (which makes sense even for steam-powered craft), then a sail structure could easily be used for propulsion. |
Syrinx0 | 18 Jun 2015 7:49 p.m. PST |
Or sails on all quadrants of the ship? |
Virtualscratchbuilder | 18 Jun 2015 8:25 p.m. PST |
Back in the day I toyed with this idea and came up with a combination of sails atop and an airplane wing below. The wing, tuned to the direction of the wind, produces lift in the direction the ship needs to move, and the sails produce additional motive power.
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Extra Crispy | 18 Jun 2015 9:32 p.m. PST |
I was thinking masts jutting out like oars from the sides – easy to pull in when the enemy gets close and then run on power. For civilian craft, yeah sails above and maybe to the side as well. |
Lascaris | 18 Jun 2015 9:37 p.m. PST |
Sails won't work in the sky. You'll just drift along with the wind and cannot tack or sail across the wind. |
Coelacanth | 18 Jun 2015 9:42 p.m. PST |
I think this would be kind of cool. The ship could be shaped something like a sunfish -- its entire hull would be a lifting surface. There would be rudders top and bottom, to steer the ship and control her angle to the wind. it would make sense that there would be few interruptions to the smooth hull, with only a small lookout deck above, and the control gondola below. Ron |
zippyfusenet | 19 Jun 2015 4:49 a.m. PST |
If this is not our earth… Imagine a world with very steady trade winds, blowing in different directions at different altitudes. To travel east, you rise to 5,000 feet. To travel west, rise to 10,000 feet. Storms present a problem. In our world, storms were really what killed lighter-than-air travel. Never mind the Hindenburg, look up the Shenandoah, the Akron and the Macon. We just couldn't build an airship that was strong enough to fly through a violent thunderstorm, or fast and agile enough to get out of the way. Maybe this world doesn't have storms very often at all. |
TheBeast | 19 Jun 2015 6:41 a.m. PST |
@Zippy That's what I suggested on a Space 1889 list, but added very laminar flows to the levels. Rising to a boundary, you have a top sail catching one direction, and 'keel' sail another, and you get a choice of vectors between. I voiced a wise Martian captain taunting earthers and their brute force steam ships fighting prevailing wind, when his knowledge sent him speedily where and when he wished. Sad thing was, the accepted mechanism was a skyship engaging liftwood, would drift to a great height, then, allowing gravity it's purchase, to glide down. I don't think anyone bothered to look up how fast you'd 'rise' from the centripetal, especially on Mars. Doug |
wminsing | 19 Jun 2015 7:43 a.m. PST |
Yes, you can't tack (nothing to tack against) if you're using sails alone while airborne. However, that doesn't mean that sails won't *work*, it just means that you're going to cruise along with the local jet stream no matter what. If you're going in the same direction then sure, hang out a sail. Virtualscrathbuilder's idea of a wing sail has promise, or maybe you could hand-wave some 'gravity drag' from the lift system that would allow some sort of tacking to occur as Parzival points out. -Will |
Virtualscratchbuilder | 19 Jun 2015 11:08 a.m. PST |
Or you could always sail them like big gliders. Instead of gaining distance when running with the wind, gain height, then turn into the wind move forward by descending at an angle sufficient to overcome the wind. Then when too close to the ground, turn with the wind and gain altitude again, repeat as often as needed. Labor intensive, but it is fantasy. |
ScottWashburn | 19 Jun 2015 11:32 a.m. PST |
How about those helix-shaped windmills to power a propeller? |
JimSelzer | 19 Jun 2015 12:21 p.m. PST |
worked well in the Dray Prescot books |
DS6151 | 20 Jun 2015 3:46 p.m. PST |
Sails won't work in the sky. You'll just drift along with the wind and cannot tack or sail across the wind. Good point. The anti-gravity flying, Victorian era, wooden ships in the sky using sails would make the whole thing…weird. |
Extra Crispy | 22 Jun 2015 8:14 a.m. PST |
Thanks – that gives me lots to chew on…. |
Syr Otto | 22 Jun 2015 10:03 a.m. PST |
When I used to run a S1889 campaign back in the 90's the handwavioum we agreed to was that the liftwood keel would interact with the atmosphere much the same way a sailboat's keel interacted with water. That and a bit of willing suspension of disbelief and there you go. So just come up with a (Victorian SF) explanation and go with it. After all, cavorite/liftwood/unexplainuim are all just a bit of handwavioum. |
Adam name not long enough | 22 Jun 2015 12:30 p.m. PST |
Sorry, your science must be different to mine. The anti- gravity devices that combine the Thomson-Tesla effect with Edison's enhanced parabolic stabilisation means that not only can craft rise or fall on successive magnetic fields but that they are extremely stable. Indeed, twisting such a craft is akin to trying to twist a gyroscope. The higher the current in the Edison Parabolic Array (EPA) the harder to twist, like a faster spinning gyroscope. This means that turning the hull relative to the flows of magnetic flux can only be achieved by reducing the current, the lower the current the quicker the turn, a bit like pulling the tiller on a small boat. The Thomson-Tesla effect not only allows the craft to rise through successive magnetic fields (slightly unpredictably if you don't have the EPA or an equivalent) but it also keeps the hull orientated along lines of flux – if the ship is naturally aligned to North varying the power will make it turn towards North from whatever position it is currently stable in, reversing the polarity makes it twist the opposite way. Maintaining a static position within the Thomson-Tesla fields requires little power, and the EPA only really requires power for stability in altitude corrections, lateral or rotational stability isn't too much of a drain. So, wind works well as the magnetic lines of flux around the earth act in a similar manner to the water on a sail boat but, once higher 'combat' speeds are required the EPA must be turned down to allow the craft to be pushed through lines of flux – mixing sail and powered flight is not a good idea. Moreover, periods of high electro-magnetic interference (aura borealis) cause real problems for all types of Thomson-Tesla devices. |