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This topic contains 12 replies, has 9 voices, and was last updated by  Stephen Madjanovich 5 days, 4 hours ago.

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  • #90509
    Darkest Star Games
    Darkest Star Games
    Participant

    Had an interesting conversation with a friend the other day about grav tanks.  We had different views of how such a vehicle would probably be used.  I am very interested in y’alls opinions on this!  How do you prefer your grav/do you think grav tanks should/would be used?

    "I saw this in a cartoon once, but I'm pretty sure I can do it..."

    #90511
    Ruarigh
    Ruarigh
    Participant

    I guess it depends upon how you think the technology might work. My Laserburn Imperial army uses grav vehicles that can reach orbit, albeit slowly. They function best at lower levels but the grav engines give control when they are dropped from orbit and can return the vehicles to their interstellar transports. I imagine my troops screaming down from orbit in their tanks and transports, but doing the real fighting closer to ground level, with the troops deploying from their transports by jetpack when they get closer in. I’m a huge fan of orbital insertion and ortillery, even if it is never really modelled on the games table.

    One other thing would be to consider what early grav tech might achieve versus later grav tech. So much will depend upon your setting how advanced you imagine it to be.

    Never argue with an idiot. They'll only drag you down to their level and beat you with experience.

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    #90517

    Mr. Average
    Participant

    It would have to have a significant benefit beyond what a tracker, wheeled or GEV tank could provide in order for it to be a viable alternative. In my mind it would be more maneuverable, primarily. That is to say it would be very fast (VERY fast) and probably capable of NOE or TERCOM movement to evade anti-grav tank missiles, and also probably stealthy.

    Personally I like the idea of a LODAV like Darkest Star makes – larger than normal, streamlined, designed for orbital assault in the way we do amphibious landings now, but without the dangers associated with small numbers of large downships or landing craft. Many small, erratically-moving vehicles that form a distributed target on descent, but then can gather to breach and establish a planetary beachhead. Probably, in my universe, that would be where the balancing act would end – rarer and more expensive drop-assault weapons would be withdrawn as more conventional forces reached the planet’s surface to begin the ground assault in earnest.

    They could have some advantage on worlds with lots of water or other liquid (like Titan’s methane seas), but that would be limited. I could see specific formations like Lift Brigades to attack a planet, followed up by armored and infantry formations.

    #90518
    Angel Barracks
    Angel Barracks
    Moderator

    My RDF had more like advanced hovercraft than anti-grav.
    Though I guess it could be used as anti-grav, whatever the difference is.

    However the Crimson Alliance have anti-grav tanks, they were used on other planets where the force of gravity is weaker than on Earth.
    Back on Mars where they were intended for use, they were pretty zippy, however on Kometenmelodie they were quite sluggish and not that great.

    #90520
    Darkest Star Games
    Darkest Star Games
    Participant

    In the Dark Star ‘verse there are 3 generations of grav, each with it’s flaws and perks:

    1st Gen: very basic, usually large anti-grav plates retrofitted to existing vehicle chassis.  Not a lot of lifting power, so mostly used for light vehicles such as light tanks, scouts, and IFVs.  Al lot quieter than hover or even tracked vehicles.  Can levitate up to 10′ a.g., though going that high reduces speed significantly.  Can cross over shallow water, but deep water (like oceans) can cause some field collapse.  Not strong enough to push into trees and has a difficult time with steep slopes, but basically acts as standard armor.

    2nd Gen: first dedicated grav vehicles.  Aircraft are augmented with anit-grav for increased maneuver and for reduced lifting surface need.  Armored vehicles are able levitate up to 100′ a.g. and can negotiate steep terrain (as long as it is not vertical over 100’).  With a little speed can knock down trees and move through light forest, but not thick stuff.  Large bodies of water are not an obstacle.  Most vehicles utilize pop-up attacks as well as fast NOW travel.

    3rd Gen: very powerful propulsion units mostly used on LODAV (Low Orbit Drop).  Most craft capable of reaching orbit.  Extremely fast travel, verging on hypersonic.  The line between aircraft and armored vehicle are blurred to nonexistence.    AVs can exert enough force to bulldoze through thick forest (if their structure can handle the strain).  3d printing of hulls allow grav plates to be homogeneously woven into the vehicle structure for optimal performance, rather than being a unit that is installed later.  It is interesting to note that Venturian 3rd gen vehicles also have thrusters for use in space beyond just being dropped.

     

    Most nations use 2nd gen as their standard for their combat vehicles due to cost.  3d gen grav is usually reserved for assault forces, orbital insertions and the like, used most heavily by the Federation.  The Solar Hegemony almost exclusively use early 2nd gen grav that is cheap and clunky, while the Han use mostly advanced 3rd gen (more than half of their troops fight in “battle pods” rather than powered armor and require a tender/carrier AV) and their MBT is just as much a flyer as a tank as it’s weapons installations are able to fire downwards from altitude if necessary.   Still, there are times and budgets for tracked and wheeled vehicles to operate in, and most 2nd line troops or poor governments put them to extensive use.

     

    "I saw this in a cartoon once, but I'm pretty sure I can do it..."

    #90553
    Darkest Star Games
    Darkest Star Games
    Participant

    Back on Mars where they were intended for use, they were pretty zippy, however on Kometenmelodie they were quite sluggish and not that great

      Is this due to the weight of the vehicle, too much gravity, or weak lifters…?

    "I saw this in a cartoon once, but I'm pretty sure I can do it..."

    #90557
    Mike
    Mike
    Keymaster

    In my fluff, anti-grav is still a new tech and on Earth like gravities just not efficient in terms of energy usage.
    However due to Mars gravity being less, the same tech whilst a bad trade off on Earth was actually pretty efficient on Mars.

    So in summary, they built the tech on Earth but the cost to make them lift was just too expensive in cash terms, why re-invent the wheel if it is not as good, stick with wheels/tracks or full on flyers.

    But when they got to Mars, it made sense to use them as they actually offered an advantage.

    #90575
    Darkest Star Games
    Darkest Star Games
    Participant

    I like that a lot.

    "I saw this in a cartoon once, but I'm pretty sure I can do it..."

    #90582
    John Treadaway
    John Treadaway
    Participant

    All of that sounds pretty good. For me, antigrav comes as a result of faster than light drive in star ships. To stop the crew being turned into red jam on the rear bulkhead, you need something to counteract inertia (I figure). When you can do that, you can control gravity (I also assume).

    But star ships are big and have loads of power. Getting the tech small enough to work in a tank might be something else. Perhaps that needs a different form of the technology.

    Beats me. Blowers to the fore, I say…

    John Treadaway

    www.hammers-slammers.com
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    #90590
    irishserb
    irishserb
    Participant

    In my own little world, anti-gravity or “grav” propulsion technology  is a relatively rare, high end, energy hungry technology.  It isn’t truly anti-gravity, nor directly related to space propulsion, and revolves around a “repulsor beam” technology that requires something to repel or push off of.  Thus, vehicles can use it by pushing off of earth, but it is not that great for flying contraptions.

    Low altitude can be achieved, generally limited to tens of feet, but at the expense of speed, otherwise, ride heights of only a few feet are typical.  High speeds, up to 130-140 miles an hour can be achieved over smooth surfaces, but the more irregular or softer the surface being crossed, the slower the vehicle goes.

    Though I’ve only used a few of them, relatively light weight assault vehicles somewhere between amtracks and hueys, designed to operate between 3 and 40 feet off of the surface are used.  There are also light gunships of similar capability, recce vehicles are a little more agile and higher flying.  Heavy vehicles stay low, and have to more around obstacles like boulders and rigid structures.  Their mass dictates what they can smash through, but can risk “beaching” themselves, which usually involves very slow movement, while engaging the construct.

    Things can be crushed by grav vehicles, so people and fragile structures beware, depending on ground pressure ratings.  Foliage can also be victim, but big trees will survive lighter vehicles, though maybe with some damage.

    I’ve also played with short range weapons, tools, and engineering devices employing the “repulsor” technology to move things out of the way, or pound things into mush.

    #90618

    greg954
    Participant

    In my world hover vehicles are some what rare. Very much like advanced hovercrafts and less like high flying anti grav. In fact they preform very similar to hovercrafts now. Effective over flat terrain like, ice, snow, water, marsh and wetlands. Not so good for steep and rough terrain.

    But do offer more lower maintenance option over tracked vehicles. However, in the aftermath of WW3. Where a lot of nukes were used and various number of other EMP based weapons. Any vehicles which relied on electronics were simply shutdown. Rendering these types of vehicles useless.

    So the general trend has been to use tracked/wheeled vehicles more over anti grav ones. A CP PathFinder or DSG Talin would still be able to move if struck by EMP. Even if the gunner had to aim manualy and the driver losing some aids.

    #90630
    Darkest Star Games
    Darkest Star Games
    Participant

    Things can be crushed by grav vehicles, so people and fragile structures beware, depending on ground pressure ratings.

    Just had a vision of a grav AAV7 popping up to 20′ and then dropping on a trench while putting power into it’s lifters at the last moment to stop it from bottoming out, the lift-field splattering the sheltering enemy just before the Marines spill out…  Sort of the future equivalent of doing a track spin on a bunker.  Dang that’d be messy!

    "I saw this in a cartoon once, but I'm pretty sure I can do it..."

    #90799

    Stephen Madjanovich
    Participant

    Great replies. Reminds me of the discussions generated by Traveller in the old Journal of the Traveller’s Aid Society.

    I always wondered about the physics of anti gravity. In my mind that would give a lead on what equipment was capable of. How DOES anti-gravity WORK? The jump in technology to create AG would be a major step or leap. From there would it be just development of technology, manufacturing, etc. which would give improvements in weight, efficiency, volume, and cost. So basically higher technology levels would give gradual improvements. Or would there be differing technologies which would provide steps of capabilities or logarithmic improvements. The poster who considers in their universe anti grav is more akin to repulsor technology has a very good idea as well. I wonder if you ever read the original Buck Rogers novel, Armageddon 2419? I always had an image in my head of using 1930s technology to control atomic reactors providing power to these experimental rays. Think of the scenes in Metropolis with gangs of people turning great dials to keep adjusting critical settings while watching banks of dial indicators (a la Forbidden Planet). The whole image is rather Faustian.

    In either case a specific desired capability would require an amount of energy. The limits imposed above could be overcome by installing greater power sources but at the law of diminishing returns. So rather than limit performance capabilities to tech levels the supporting technology would combine with the level of development of the AG itself to provide the inherent limits. But it would allow for certain niche applications. Think a “low tech” grav APC could only perform at a certain level and still haul all your crew, weapons and armour around. While a rich guy’s equivalent of a Bugatti which only has to haul them, a trophy companion and enough power plant, fuel and enough fuselage to hold it all together at speed could blow the socks off that APC.

    On another note ACVs. I was reading about the brown water navy in Vietnam and came across some interesting revelations on the hovercraft they used. Seems they were very fast and could react and be on station with an infantry squad well before any other unit could BUT they were hellishly loud. No chance of not having the VC knowing they were coming miles away. In my mind this would still be the case in any future or sci fi environment as the cause of the noise, the air cushion being generated and escaping the skirts remains. More so in some of the designs with no skirts as the air spill would be massive and continuous as well as needing constant supply of high pressure air. So forget stealthily invading any thing. Plus in order to provide forward (or other directions) thrust to move or maneuver would require additional sources of thrust or again even more massive diversion of the one source of high pressure air. In summation ACVs are gonna be loud suckas and have poor capabilities where traction would be needed, such as climbing steeper inclines (unless you rush them), pushing through brush, boulder fields, irregular ground, etc.. They would be limited to open waters, marsh with open vegetation, clear fields or roads. So wheeled or tracks should still rule until gravetic technology is quite mature. Instead of mine fields think fields of open grating where the cushion would be lost dropping the ACV onto the grates.

    One other thought, if you don’t agree with my concept of how gravetic technology would evolve how would you explain why lower tech/earlier generation gravetics would be more limited in their capabilities?

    As a disclaimer I come from this with a great love of Traveller and especially Striker which addressed many of the issues and limitations by the inherent build sequences.

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