AnotherDilbert
Emperor Mongoose
I wouldn't know, but I imagine not. I agree that we can't draw conclusions based on small details in illustrations.h1ro said:
Gas giant refuelling
- Thread starter phavoc
- Start date
Reynard
Emperor Mongoose
About the only time I saw a definitive illustration for and engine/drive was from the MegaTraveller Starship Operator's Manual which shows what a thruster plate looks like and how it operates along with a schematic diagram showing auxiliary orientation thrusters for roll, pitch and yawl. I *think* I remember another source showing the thruster plate in a gimbal assembly. They even explain why the thruster plate are in the ship stern.
I believe one of the Secrets Of The Ancients missions actually had (traveller 1e) rules for pottling around inside a Jovian's atmosphere at various depths.
[goes off to google a bit]
Secrets Of The Ancients part 3 - 'The Hunt'
Gives you the table - it's on page 21.
The gas giant in question is rather smaller than Jupiter (about 38000km radius, about halfway between Neptune and Saturn in size) but the idea - depth provides a sensors and piloting penalty, and regular checks which cause damage to a ship, can be read across to any function.
I'd definitely agree with a bay weapon on an SDB. It's a reasonable swap for a jump drive and jump fuel, and the punch from a really big gun can knock a hole in even a 'proper' warship and go a long way to giving a group of SDBs a fighting chance against enemy capital vessels if it can catch them 'at anchor'.
Building your SDB with (again, 1e) a streamlined hull and aerofins gives you no net penalty on piloting checks at 2000km depth, and if you're drifting slowly and carefully, probably a net DM+2 (changing time increment up for an easier skill check). Obviously the sensors DMs are reversed when talking about being picked up from the surface, but as it's the middle depth it works out the same - a DM-4 to see or be spotted from the surface. Throw in Stealth Coating as well and that's a net DM-8 - enough to make picking you up really, really unlikely unless a ship has Very Advanced sensors, a good sensor operator, and is specifically looking for you.
You'd probably not want to stay at that depth indefinitely - because you'll fail a piloting test eventually and 2D6 damage hurts on a small(ish) ship - but cruising around at 1000km depth and 'diving' to attack once prey is spotted (especially since likely prey is probably diving to 1000km depth itself) makes sense.
[goes off to google a bit]
Secrets Of The Ancients part 3 - 'The Hunt'
Gives you the table - it's on page 21.
The gas giant in question is rather smaller than Jupiter (about 38000km radius, about halfway between Neptune and Saturn in size) but the idea - depth provides a sensors and piloting penalty, and regular checks which cause damage to a ship, can be read across to any function.
I'd definitely agree with a bay weapon on an SDB. It's a reasonable swap for a jump drive and jump fuel, and the punch from a really big gun can knock a hole in even a 'proper' warship and go a long way to giving a group of SDBs a fighting chance against enemy capital vessels if it can catch them 'at anchor'.
Building your SDB with (again, 1e) a streamlined hull and aerofins gives you no net penalty on piloting checks at 2000km depth, and if you're drifting slowly and carefully, probably a net DM+2 (changing time increment up for an easier skill check). Obviously the sensors DMs are reversed when talking about being picked up from the surface, but as it's the middle depth it works out the same - a DM-4 to see or be spotted from the surface. Throw in Stealth Coating as well and that's a net DM-8 - enough to make picking you up really, really unlikely unless a ship has Very Advanced sensors, a good sensor operator, and is specifically looking for you.
You'd probably not want to stay at that depth indefinitely - because you'll fail a piloting test eventually and 2D6 damage hurts on a small(ish) ship - but cruising around at 1000km depth and 'diving' to attack once prey is spotted (especially since likely prey is probably diving to 1000km depth itself) makes sense.
AnotherDilbert
Emperor Mongoose
We seem to be recursing, and I'm not sure what or if we are disagreeing about.Reynard said:
MT ships can use agrav, thrusters, or both, as per the Maneuver Drive Unit table on p65.
Most standard ships seems to be using thrusters, not agrav, e.g. the ships in ImpEnc, pp78-85.
My conclusion: MT spacecraft do not generally use agrav.
Agreed.Reynard said:
I disagree. As far as I can see MgT is based on CT, it is not a simplified T5. I let each edition stand on its own.Reynard said:
The optional movement system in MgT HG clearly shows spacecraft being pulled by gravity, as they would not be if they were equipped with agrav.
My conclusion: MgT spacecraft do not generally use agrav.
MgT Core, p137: Atmospheric Operations:
A spacecraft might be operated with the Flyer(winged) skill, never the Flyer(grav) skill.
My conclusion: MgT spacecraft do not generally use agrav.
Antigravity isn't necessarily the right phrase. Antigravity (in the sense of being unaffected by external gravity wells) is not necessarily the same as a Gravetic drive - meaning you generate your own gravity well and "fall" into it; the result of the latter will be an acceleration which is the sum of any 'real' gravity well and the 'artificial' one (which, in the case of an antigravity 'floating crate' or something, is zero acceleration either way). I agree that Mongoose has been deliberately vague about what exactly an M-drive is and how it works, but it clearly is gravetic.
From high guard - discussing reaction drives:
"The reaction drive takes the same space as a gravitic drive" - meaning that the conventional M-drive is gravetic.
Observation: That is specifically for a streamlined ship. The point of being streamlined is the ability to behave like a modern aircraft or winged animal - i.e. following the laws of aerodynamics in order to be able to make more dramatic manoeuvres.
A flyer (grav) like an air/raft may be able to move in essentially any direction, but it's not unreasonable to assume it's going to handle like a high-tech analogue to a zeppelin, and a standard (non-streamlined) starship might well handle the same way. If you want to fly around like a jet fighter at supersonic speeds, you need to deal with airflow, and hence - I agree - you're either using thrusters or a manoeuvre engine which is locked forwards (which might as well be thrusters).
Gravetic propulsion works on an air/raft, and allows the thing to potentially reach orbit. Simply starting on the ground, setting the propulsion direction to "up" at 1.00001g and waiting will eventually put you at orbit altitude ("Air/rafts can even reach orbit") with a minimum of fuss and effort (even if it takes a while), and if gravetic propulsion can work in atmosphere, there's no reason that gravetic starship drives can't.
(As an aside here, though, depending on how the 'gravity well' produced by the drive is perceived by air near to the ship you could produce some bloody weird turbulence around a ship under gravetic drive)
From the 1e core book discussing landing:
Since the skill remains a Pilot (spacecraft) check, one can assume the broad technology remains the same as for piloting it in orbit, whilst using aerofins and a streamlined hull with powerful forward thrust, combined with lifting surfaces dramatically changes the way a ship handles.
AnotherDilbert
Emperor Mongoose
Yeeess, even worse for my argument, HG p57:locarno24 said:
I've heard thrusters referred to as "gravitic" since they are supposedly based on gravity and the strong force, so I don't think that meant much, but the quote specifically says agrav.
On the other hand streamlined craft have wings for lift.
I will agree I was wrong about MgT, and put MgT in the confused category.
Reynard
Emperor Mongoose
OH... while we're 'discussing' gas giant flight, I thought I'd remind y'all that, according to one adventure for Azhanti High Lightning (Rules booklet pages 39-40 Incident V- Dead Ship), you can in fact land on a gas giant. The frontier cruiser Haunting Thunder was ambushed by Zhodani SDBs while it attempted refueling and 'lies adrift, tail down, in an ammonia sea on the surface of the gas giant, buoyed up by it's empty fuel tanks...'. Yeah.
Your party Lands nearby to scramble onto the cruiser hull and set up a hoist tower and winch to climb inside and extract a valuable prototype fighter. The waters inside the ship has blobs. Soooo, I wouldn't sweat how well you can traverse the atmospheres of gas giants.
Your party Lands nearby to scramble onto the cruiser hull and set up a hoist tower and winch to climb inside and extract a valuable prototype fighter. The waters inside the ship has blobs. Soooo, I wouldn't sweat how well you can traverse the atmospheres of gas giants.
AnotherDilbert said:
I thought I had made that clear. The issue is not about the main drive. The issue is about what mechanism a ship uses to provide vertical lift (or buoyancy, though I don't feel that is the proper reference for a MUCH heavier than air craft!).
AnotherDilbert said:
Whoa.. You really would call an Azhanti High Lightning class a tail sitter? Maybe we need to revisit what a tail sitter is. A tail sitter is a craft that takes off and lands like a standard rocket. Middenface's Atticus class Freelancer is a tail sitter. The Sloan isn't, the AHL isn't, and I don't believe the tender is either. Tail sitters were poplar in 50s sci-fi shows, and SpaceX's rocket (booster at least) is a tail sitter. At least by the term that I'm using.
AnotherDilbert said:
Having wings isn't the only issue when it comes to lift. Mass has a huge effect on lift, as does the atmospheric density. Worlds with thin atmospheres provide far less lift than one with a standard or dense. And of course vacuum worlds provide no atmosphere for lift at all. Starships that expect to land need to handle a wide variety of worlds, thus it goes back to the idea that the wings on these ships primary function isn't to provide lift to take-off/land. If that were the case then there would be a whole host of worlds and moons they could not land on. Nowhere have I seen warnings of limitations to these craft about where they may or may not land.
AnotherDilbert said:
I don't disagree about canon, though I do think that the explanation is somewhat circular. It's rather frustrating that the SOM was a great leap forward in an attempt to explain the underling tech, but it seemed to make a few mis-steps. But TNE also had an explanation, as did the FF&S, which as official books also are canon materials.
AnotherDilbert said:
I don't agree with this. It's not mentioned either for or against, which is how this discussion started in the first place. One assumes that it's there (or not). Or at least this one assumes.
Reynard
Emperor Mongoose
I mean... BLOBS IN JOVIAN AMMONIA SEAS!! That's so Buck Rogers! (And Buster Crabb and his gang have landed on Jupiter and Saturn).
I'd say today the descriptor of that adventure would be occurring on a Size 10, Hydro 9+ world with heavy moisture vapor atmosphere for emergency skimming.
I'd say today the descriptor of that adventure would be occurring on a Size 10, Hydro 9+ world with heavy moisture vapor atmosphere for emergency skimming.
AnotherDilbert
Emperor Mongoose
Decks perpendicular to the axis of thrust.phavoc said:
I don't we will convince each other, so we will have to agree to disagree?phavoc said:I don't agree with this. It's not mentioned either for or against, which is how this discussion started in the first place. One assumes that it's there (or not). Or at least this one assumes.AnotherDilbert said:
AnotherDilbert
Emperor Mongoose
Hehe, what's next; swimming in the pleasantly warm plasma of the Sun?Reynard said:
AnotherDilbert said:
Hrm, I was not thinking in that mindset, but you are entirely correct. The AZL ships did have their decks perpendicular. In my mind a tail sitter was a lander, since that was the entire point of the discussion (take-offs and landings). But your point remains valid.
AnotherDilbert said:
Sure!
Condottiere
Emperor Mongoose
Power plants and jump drives seem very clear, manoeuvre drives and reaction rockets appear somewhat vague.
Essentially, open to interpretation as to how they are or can be used.
Essentially, open to interpretation as to how they are or can be used.