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Grav vehicle movement

Is it scientifically feasible for a grav vehicle to rotate and face another direction while maintaining movement in another direction? A bit like spaceship vector movement.
 
Given the tendency in published designs to emulate tanks with turrets or high speed fighters with forward-facing guns, the behavior you describe is probably not something Canon grav vehicles can do. You wouldn't see many turreted vehicles if it were the case.

Some hypothetical grav drive without that history of design might, but would probably come along with a form of force field shielding that allows a traversing craft to remain favorably aerodynamic.
 
I think it would be a bit like vector movement. However, in an atmosphere there would be drag which would slow the tank down. Drag would increase with dense atmospheres.
 
Thanks. I think I will stick with the notion that they can't vector and still require turrets etc. Purely from an aesthetic point.

How would a grav vehicle manouevre? Would the grav generators provide the force to move and change direction / height? Would some sort of control surfaces be needed?
 
It's funny, I just started thinking about this last night, completely independently, while considering one of two Traveller ground combat game designs. This one is based on an adaptation of a space game, of all things.

Yes, a grav vehicle can clearly pivot sideways without changing vector. Yes, there would be more drag, but if you look at the shape of the Trepida, it does remarkably well sideways. Yes, there would be enormous buffeting, but modern fly-by-wire systems allow aircraft that are both statically and dynamically unstable to fly perfectly smoothly. A TL-12+ vehicle computer would handle far worse with ease.

Exactly how a grav vehicle thrusts is a matter of debate, but it's perfectly reasonable to assume two primary sets of grav plates/lifters: one under the vehicle and one to the rear. Additional controls of some sort are necessary to rotate the vehicle; after all, you can't imagine a grav tank that can't rotate in place, can you? These would probably be additional sets of grav plates/lifters, but with much less thrust than the main two. After all, their main purpose is attitude changes and stability control.

Given this, there's a definite reason to have a turret: if you want to accelerate in any direction other than the one you're firing, you must have a turret. Also, if you're side-on to your vector, your drag is going to be higher than if you're facing directly into the airstream. If your rear isn't pointing to allow you to counteract the drag with thrust, you're going to slow down. If all you want to do is take one snapshot, it's no big deal, but if you want to do anything beyond that, not having a turret really is a problem. A turret also allows to your point your heaviest armor at a threat while moving in another direction. Remember, your hull is always going to get some protection from the undulation of the grounds, various ground-level obstacles, and so forth. Finally, consider a really good hit-and-run position. You're placed behind an obstacle with only a sensor cluster peeking above it. Your turret faces the threat (ready to fire), while your hull faces the other direction (ready to run). That brings up yet another benefit of a turret--you can keep firing while you run away!
 
It probably will depend on the ruleset in use, and what the referee will allow. ;-)

For example, under MT you could argue that the SoM rules are a good guideline: thrusters give 25% thrust sideways, dropping to 10% in full reverse.

Whether this applies if you are using grav plates, is up to the ref. In a high speed spin-turn, I'd certainly force the driver to a Grav Vehicle skill roll, tho'!
 
The speed you are going at the time is also going to affect everything else you attempt.

You'll get the occasional hot shot pilot who can skid-turn in mid-air and make it look good, but most Grav Vehicle-1 fliers are going to limit their traverses to defensive jinking and low-angle drifts at best.
 
Personally I see grav warfare occurring in different battlespaces - ground, airspace and close orbit. You would have ground combat - up to about 2-300metres off the ground. Grav vehicles designed to operate in this environment would be similar to the armoured vehicles we have today. There are times when you are still going to have to take and hold ground in the future - you can't turn everything into a glass car park from space.

Grav vehicles designed for use in the airspace would be more like "aircraft / gunships" to use an analogy. There is no cover and combat would be extremely fluid. These gunships would vary in size - from the "fighters" to larger gun platforms - like the large gunship in Avatar. Their role would be to secure air supremacy and assist in ground/close orbit combat.

Close orbit - probably a Naval responsibility. Able to support ground and airspace combat.

Future warfare would be complex, 3d and require excellent command and control.
 
To quote from LBB4 Mercenary yet again:

Tech level 12: All vehicles have sufficient free-flight performance that ground combat
vehicles effectively no longer exist, having merged with aircraft. The primary weapon of the heavy gunships...
 
To some extent, we already see Attack Helicopters taking on more traditional 'tank' roles ... especially those roles historically performed by lighter tanks.
Grav Drives can only push that envelope much further.
When the MBT can fly ...
 
The answer is clear from CT/Striker - grav vehicles at NOE speed can "vector" (for lack of a better word) regardless of their direction of travel. See page 27 of CT/Striker Book 1. "Grav vehicles moving at NOE may face in any direction at any time; grav vehicles moving at cruising or maximum speed must face in the direction they are moving."
 
Got a question.

So, if grav vehicles can use vector movement (and I agree with that), then why do grav tanks have turrets? I mean, you have a turret on a modern MBT so that it can move one direction and shoot in another and it is surface bound.

Those aren't problems with a grav tank, so why not make them the vehicle equivalent of spinal mounted ships in space combat? A shell of armor around a big gun with some point defense for drones, arty, and infantry attacks seems a better grav tank than the grav capable modern MBT we always see portrayed.
 
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Under Striker rules, NOE is generally the slowest design speed, so the need to keep to "face forward" above that speed is almost certainly a matter of aerodynamics, not grav drive capability. It may also be an effect of Striker's sometimes odd approach to simulation; it may be the case that lots of facing changes are within the control capability of the grav drive at slow speeds so the need to turn, move, turn again is simply glossed for game purposes.
 
So, if grav vehicles can use vector movement (and I agree with that), then why do grav tanks have turrets? I mean, you have a turret on a modern MBT so that it can move one direction and shoot in another and it is surface bound.

Those aren't problems with a grav tank, so why not make them the vehicle equivalent of spinal mounted ships in space combat? A shell of armor around a big gun with some point defense for drones, arty, and infantry attacks seems a better grav tank than the grav capable modern MBT we always see portrayed.
Because you want to keep your weapon on target while you conduct evasive manoeuvres.

And once again TL12+ grav 'tanks' do not exist - they are gunships and they are better modelled as an attack helicopter with MBT scale armour rather than a flying tank. 20th century writers were just more comfortable using the incorrect term.
 
My contribution to this thread...

traveller_air_rafts_by_arcas_art-d6lsox5.jpg
 
So, if grav vehicles can use vector movement (and I agree with that), then why do grav tanks have turrets? I mean, you have a turret on a modern MBT so that it can move one direction and shoot in another and it is surface bound.

Those aren't problems with a grav tank, so why not make them the vehicle equivalent of spinal mounted ships in space combat? A shell of armor around a big gun with some point defense for drones, arty, and infantry attacks seems a better grav tank than the grav capable modern MBT we always see portrayed.

the driver can look ahead while the gunner looks elsewhere
 
Driver/Gunner.

the driver can look ahead while the gunner looks elsewhere
The Driver/Pilot is the Gunner that was the point of using a spinal. Commander (if any needed) covers point defense and picking targets.

Though, I don't see why we don't just plug a Robo-Citizen in the hull, but sadly I am a minority. Silly meat-centric attitudes, ooo meat is all special and non-organics are icky and scary.
 
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