The Zenith and Nadir points of star systems can operate as Lagrange points, where gravity is balanced or neutral for the KF drive to function properly. There are also Lagrange points closer to planets and their moons, annotated as L1,L2,L3 etc. Like where the James Webb telescope is orbiting. These points also exist throughout a system and move sequentially with orbiting bodies. The BT universe calls these 'pirate jump points '. This dramatically reduces transit times and are more difficult to defend, however larger strategic systems often have Castles Brian defence networks or analogs within these vectors. The fusion drive systems of dropships / warships can burn into position with as much haste as the crews can tolerate the G forces.
To add on to that. Pirate Points are also more dangerous to Jump to as their location relative to the system as a whole moves more. Making a FTL jump to one having a higher likelihood of failure. Which is another reason why, outside of pirates or certain wartime attempts, they are avoided by most.
An important fact about those "pirate points" is that very up to date info on orbitals are required to properly jump there. And by "up to date", usually under a century or so. In other words, the time it takes for light to go from a star system to another one would make that data too out of date to use. It makes jumping to those points rather dangerous. The advantage of zenith and nadir points is that they're equidistant from any planet in the solar system, since the orbits of planets around stars will tend toward a flat disk (just the result of conservation of rotational momentum in 3 dimensions). It's *technically* possible to jump to any point outside the gravitational proximity limit of the star (about 10.2AU for Sol), but there'd be little point in it. Strategic Operations (StratOps) page 132 has a great image showing all that off. Dropships usually transit at 1G acceleration. It's possible to go faster, but human bodies don't do well at 3G or more for extended periods of time. StratOps has a table on page 70 detailing the time it takes to travel different distances under 1G acceleration. BT's dropships can go from Earth to the moon in about 4 hours (minus time taking off). On closest approach to Mars, they can go from Earth to there in 1.75 days. From Earth to the Sol Nadir or Zenith points is 9.1 days. But the biggest time sink for jump travel in Battletech is waiting for the KT drive to recharge. There's a table in StratOps on page 87 that details how long it takes to recharge, depending on star type. These follow the same Stellar Classification system used by astronomers; our sun is a G2, so it would take 183 hours to recharge at Sol. I'd suggest finding Strategic Operations. It has all kinds of info on how jumping works, and the timeframes it calls for. Sorry for the walls of text. And on a minor note, our current tech can get us to Mars at closest approach in about six months. Venus would be half that time.
@@Xeno426 one thing i have loved about battletech fans since the 80s ... we love our game, we love science, we love understanding the military industrial complex, we like out fiction to make sense, we understand that comstar uses a lot of the 'old soviet method' of diplomacy, we get that humans will human and a happy go lucky universe / setting just is not going to truly happen with humans involved. do not need aliens. -(we are not going to bring up the bird man incident)- humans can cause enough drama intrigue plot and horror on their own.
@@catboxvideo I liked how at the start of the Clan Invasion (yes, way back in the day) it was thought that these invaders were aliens at first. And functionally they were with their different and unfamiliar ways of doing things. Which highlights you don't need actual aliens as even humans can be very alien to each other.
Dropships usually travel at constant 1g acceleration, speeding up towards their target on the first half of the trip, than reversing and slowing down for the second half. This is done to provide artificial gravity for the crew of the ship. When they need to get to places in a hurry drop-ships can accelerate above 1G, but naturally this is uncomfortable and even dangerous to the crew, so it's done only when speed is critical, but even then we are talking about 1.5G maybe 2G.
It is absolutely fascinating! You know, I'm so used to seeing the Leopard in MW5 and just walking around it between missions that I hadn't really thought too hard about the gravity... but that makes perfect sense!
@@thevoiceofiron So, one thing that the games tend to get wrong is how the aerodyne dropships (like the Leopard) don't have VTOL capability. They have to land on clear ground. An interesting aspect of aerodynes is that their transit drive engines are on the bottom. This leads them travel to the planet with the "top" facing the direction they're going (rather than the nose). Otherwise the internal space of the dropship would have to be able to rotate about 90° so that "down" was beneath them rather than on a wall. Spheroid dropships don't have this issue, since their transit drives can be the same, or in the same location, as the regular engines. "Down" is always towards the engines. However, in atmosphere, spheroid dropships are more vulnerable to aerospace since they can't maneuver as well.
@Xeno426 Very fair. I'd read that somewhere, and I tend to write off at least the Player Character's Leopard having VTOL/Hover capability as some kind of modification since you're a merc company... though that's admittedly cope, since I can't make excuses for having the enemy dropships do it, too, lol.
The heavy restrictions on FTL in BattleTech is what makes it so interesting. It's like Sanderson 2nd Law of Magic; limitations are more interesting than capabilities. Those limitations are basically what allow BattleTech to exist in the form we know. Heck, the lack of artificial gravity is another big aspect. Dropships only have "gravity" when they're in transit to planet, or landed. In all other conditions (including halfway to their transit point) the people inside are under microgravity. Jumpships and warships tend to have "gravity decks", which are just decks that spin like in 2001: A Space Odyssey. This provides places for people to hang out under 1g or similar conditions (some of the smaller grav decks spin slower and only generate ~0.8g, still enough to help prevent all the bad things from being weightless).
You know, I've often said "If you want to be truly creative, put yourself in a box!" for this very reason! Introducing rules to something makes it feel more consistent, more alive!
@@thevoiceofiron It's also true for jumpship and warship design. There's rules for how those work, which leads to BattleTech's space ships trending towards a specific look. Because the KF drive jumps things in a bubble, the most efficient use of space is a long rod (to maximize the sphere's diameter), with everything that needs to jump fitting along it.
@@Xeno426 Nope, the jump field is not a bubble. in fact, dropships have to be connected to the jumpship to extend the field around themselves (heaven help you if the K-F boom is damaged). anything within 2km of a jumping ship will be damaged.
Deep dive on warships. Those will not only impress you with the "golden age" in battletech. They will also horrify you on the level of deployment and destruction they caused. Great video. Looking forward to seeing more!
@@thevoiceofiron You might want to look up the Age of War, the Mackie, and Tintavel. Each of these form the steps to why Battlemechs became a thing, but its due to the sheer destructive potential of Warships themselves. They cause so much devastation that the Houses had to come together and sign what's called the Ares Convention. Ponder on that a second, Houses constantly going to war with one another had to sit down, take a breather, and say "Okay I think we're going a smidge too far with our fighting". THAT is how deadly warships were. Also in terms of Dropship speed, it's always less than the speed of light. Since all the space ships in Battletech don't have artificial gravity like a Star Trek or Star Wars ship, they control gravity via thrust or rotation. We're basically playing with 2001: A Space Odyssey rules. Most Dropships like to go a speed to simulate 1G of thrust when they make their way planetside
The issue with 'sunbight' speeds in BattleTech is that most space craft list acceleration as there is very little resistance to slow you down or fight against, speed is kind of not a needed thing. in example an Overlord class drop ship has a safe thrust of 1.5 g's and max thrust of 2.5 g's, but really in space 'speed' is not a number it keeps going up with continual thrust and as drop ships approach a target point - jump ship, moon, planet - they rotate and use their thrust to counter their own momentum and - in case of planetary landing - gravity OR in docking slow and use maneuvering thrusters to dock. Transit time is liftoff to dock plus jump undock to landing, BUT if you need to make multiple jumps the recharge time can be a bitch. Depending on the jump sail (solar collector) and the stars strength. Some Older / New jump ships had a battery that would allow a second jump but these were included in tech that was bombed out of the setting for a long time the most part. to travel great distances in a hurry you would need a 'pony express' style of routing but would have to be a Major power or stupidly rich to have that many jump ships available to you - otherwise it is jump maybe wait a few days or week plus then jump... and on. Warships on the other hand had Jump drives and large sunlight drives and would deliver their drop ships much closer to target as well as having some serious fire power. Again, bombed out of the setting for a long time. Lastly, there are 'Pirate Points' that are closer to planetary bodies, buuut a lot more dangerous due to gravity, debris, etc. Batteltech really did try to build in some realism to their setting of stompy robots. Now GM just needs to get it in gear, their reactors were due a couple years ago.
That's what I love about the setting: Enough rules to play by and really make the setting feel alive! After all, if there are rules, you can build strategy around those rules, and the more detailed the tech, the more brilliant the writers can show the strategists to be! It makes for good writing and good reading! Also, yeah, wasn't GM supposed to invent the Fusion Reactor in 2022?
Keep in mind that "g's" are a unit of acceleration. So when a description says the max thrust is "1.5 g's", they're saying its max acceleration is 1.5 m/s^2, not its speed.
FTL in BT--though they call it a hyperspace jump sometimes--is closer to a quantum jump. The KF drive is basically a big capacitor that discharges after every jump. Unlike a capacitor, you have to trickle charge it so you don't break it, hence the energy sail. You can, in a pinch, use the fusion drive of your JumpShip to do it, though. The space magic really comes in the military DropShips which sustain a 1g acceleration and somehow miraculously use only about 21 grams of hydrogen fuel per second. A DropShip drive's output is measured in terrawatts. The fact it could power a small planet is quietly overlooked. Can't have a DropShip captain retire and become the planetary utility company when they should be transporting troops, after all.
Fair enough! I actually like that it's so complicated, or rather so energy intensive, as it grounds the setring in my eyes, and explains why the Inner Sphere is essentially the limit of Human expansion (...mostly) a thousand years from now.
One addition I would note that contributes to the travel time in the large scale of things: The KF Drive basically depletes it's charge after each jump so Jumpships and Warships can't make another jump immediately after. Instead they have to deploy energy collector sails to slowly recharge the dive, and alternatives to this process are limited as charging the drive too fast can actually damage it. The only ways to mitigate this limitation I can recall are recharge stations, which have their own energy collector sails and store power that can be transferred to a Jumpship or Warship to charge them faster, and Lithium-Fusion Batteries, a expensive and advanced piece of technology that lets a KF Drive hold a 2nd jump charge.
Ohh, very cool! Maybe one of these days, I should just read the full SARNA article on K-F drives/Jumpships on the channel. I love that FASA went into such detail for things like this, it makes the setting feel alive!
The below is based on Dropships and Jumpships by FASA. If there is a conflicting source, by all means pipe up. Jumpships have 2 ways to charge the drive. the sail or use the onboard fusion reactor. using the sail is preferred to cut down on fuel expenses. Sail deploy time100 minutes, retraction 150-200 minutes. the sail will charge at a rate dependent on the system's primary star (151-210 hours) . A recharge station can beam extra power at the sail to accelerate the charge rate. There is a maximum safe charge rate. charging in under 150 hours risks damage to the drive. The minimum safe distance to jump into or out of a system while avoiding gravitational influence is essentially a sphere. Presumably with minor perturbations for any VERY large planets. the radius of the sphere varying with the star type from as little as 0.07AU to as much as 347.84AU. The standard jump points are called the Zenith and Nadir points (North and South poles of the sphere with the plane of the planetary orbits defining the equator. These will be where any stations and commercial traffic will be. Pirate points are NOT Lagrange points. Those are something completely different. Planets are not in the exact center of the system. In the case of very large stars they can be very far from the star (Earth of course being at a distance of 1AU). If you jump to a point on the jump limit sphere that is closer to the planet then the standard jump points then that is a jump point. The Jump itself is not quite instantaneous. ( lightyears travelled/2 ) seconds plus a few seconds at each end for the field to expand and contract.
Ok, Skimmed the Hyperspace travel section of Strategic operations for changes. and some things have changed. Lagrange and 'transient' points are now valid for jumps. the minimum amount of time to safely charge the drive without risking damage has risen from 150 hours to 175. Mind you this change now means that almost half the star types on the charging time chart (ranging from 151- 210 hours) now charge faster than the drive can safely handle. Hopefully there is a way to throttle the charge rate jump ships now have the option to dock with a recharging station to recharge directly. And if then want to charge the drive and a LF battery at the same time they can SOMEHOW use their own sail while docked with the station (which would typically have it's own sail). How the sails. don't get tangled I don't know. and the jumps now take longer (light years traveled)/2 * (max dropships the JS can carry) sail deploy/retract is a little faster now at 80 & 160 minutes
@@b.s.864 When it comes to throttling the charge rate it seems like it's something that could be doable somewhat easily. In theory you could: disable the power connections to some sections of the sail so you reduce the overall power intake, have a system that diverts excessive power to other ship systems, "vent it" via an emitter of some kind, or regulate power intake by only partially opening the sail. As for how the Charge Station and Jumpship sails avoid being tangled that one also has some possible explanations. 1: Have the orientation at which the Jumpship docks at the station NOT be parallel to the axis that the station deploys it's sail. If the station sail is basically hanging far "above" the whole thing like the top of a mushroom then a Jumpship docked at a 90 degree angle to the station's central axis (making kind of a T or cross shape) can easily deploy it's sail out of the way. 2. Although they are called sails energy collector sails aren't sails in the traditional sense. They are catching small amounts of various forms of stellar radiation, such as solar light, over a wide surface radius. However when the extend out they are not being "blown" they are simply being moved to a extended position by completely mechanical means because they work most efficiently in that shape. To my understanding the radiation doesn't "blow" or really move them around in any meaningful way, they just sit where they were deployed and do their thing, only moving as a reaction to kinetic impact on either themselves or the thing they are attached to. So it should be fine so long as the sails are not literally deployed into one another.
@@Zanedor if the sails of a docked JS are deployed in a T orientation then they are not pointed at the sun and thus not charging anything. The sails on a JS are usually well over a km (tro2750 & tro3057). TRO3057 lists a recharging station with a sail 4km across. docking arms allowing a co-axial orientation would be impractical. While they call it docked, perhaps they really mean just a really long extension cord? I agree that throttling charge rate is probably not an actual issue. I have always been unsure which way the station keeping drive would be pointed. The standard jump points are incredibly far from the system's sun but are not in orbit of it. do they point away from the sun to counter the photon pressure on the sail. or toward the sun to counter the sun's gravity. does it depend on the stellar class? given these are small by true solar sail standards I imagine toward the sun is more likely.
Fun topic. Love the hard scifi of the setting, no artificial gravity, no shields, heavily limited FTL. Think the FTL needs to be boosted to 60Lightyears As the time to charge is insane, you looking at 7 days minimum 8 or 9 max… for every 30 light years is just not feasible Meaning that a single jump will take you nearly a mounth if not more garenteed, and more jumps ad on another weak…
That charge time is the safe and normal charge time. Setting has rules for doing things like trying to speed charge the drive, or having a giant battery to let you jump in sequence. For large scale military operations there's also a 'command circuit', where you station JumpShips at each stop along the route. Then the Dropships just keep changing JumpShips, resulting in much faster transit while keeping the charge time consistent. Basically a FTL bucket brigade.
7 days is nothing. Transit times from jump point to the planet can be a real bitch. There are systems where it takes *40* days! You can do 4 jumps in that time and be 120 lightyears away before Dropship traveling to, say... Zaniah, lands there.
Oh hard figures for dropships is easy standard burn is earths gavity worth of thrust. If your 2G is your battn down the hatches, every one seated for days of journy with some rest stops between. Under 3gs is typicly maximum safe thrust and this is done for maneuvering, say your attacked. Folks have a chance of blacking out once your whipping it at 3g. These can all be entered into a an equation to find times from planet to nadar and zenith. All dropships are capable of 2g burn, and this is used to calculate times for travel, typicly at 1G, so tjat you can simply divide your time by 2 if your not doing mech maintenance in your travels. Jumpships on the other hand can never reach such velocities often maxing out at 2g its most common for them to burn at just below 1g as alot of there time is simply making gravity and waiting for a jump. Having to then slow to a full stop to then make the jump and repeat.
That may make calculating the speed easier, yeah! I didn't see that on SARNA when glancing for this mini-rant, but then, it was a mini-rant not a reading, so maybe I missed it? Either way, makes sense!
@@thevoiceofiron You can find the values there in the sidebar on the right under safe thrust / max thrust, with 1.5g-2.5g being the average values for both dropship or warship (of course you've got exceptions to that). Jumpships usually have what they call a station keeping drive that's rated for 0.2g. Amusingly enough, in contrast to the more down to earth FTL, the sublight engines are pure space magic along the lines of 1950s scifi torchships.
@@thevoiceofiron Dropships and Aerospace fighters have thrust values. Two points of thrust means 1g of acceleration. A Union dropship(the default big sphere) is a 3/5, so can safely go 1.5gs and push it to go 2.5gs. A Leopard (the small plane like DS) is a 4/6, meaning that it can go 2gs without much strain on the engine. Eyeballing it the fastest fighters seem to be able to pull 10gs of max thrust, although these are standouts. Fighters or Dropships with over 6gs (8/12) are rare. Peak Star League tech had sufficiently functional AI for warships. While any AI that went through a Jump tended to go crazy, they made great system defense craft as they could maintain and adjust with thrust that would kill a crew.
@@jochenwenzel8878 pure magic? Nonsense. They are fusion mumble mumble mumble water reaction mass sometimes mumble just don't look closely mumble mumble
It's not so much that K & F could not practically test their theories at the time. It is more that their theories rejected Einsteinian relativity and institutionalized academia intrenched itself, rejected them, and turned them into pariahs the stigma for which lasted a century until a research team replicated some of their experiments and validated their theories by happenstance. Which is potentially some interesting commentary on academia as an institution. Traveling between jumpships and planetary surfaces can vary quite a lot based on dropships used, solar system layout, and urgency. If it's just a routine flight, dropships will usually burn at 1g straight through accelerating to the half way point then flipping and decelerating the rest of the way. This is a *very* fast form of interplanetary travel which predominantly uses Hohmann transfers were you use orbits and gravity to coast around instead of burning straight through. These "turn and burn" maneuvers are the most common orbital transfers used in BT. Many system/planetary pages on sarna give transit times between jump points and planets and it is this maneuver they assume. Typically the times can range from 5 days to 2 weeks from what I've seen, though I haven't done an extensive survey to find a representative average or range. However, sometimes faster operations are necessary. Important political travel can often bump this up to 1.5 or even 2g. Military operations will frequently preform these transfers using the maximum safe thrust of a dropship. From what I've seen this ranges between 1.5 and 3g. The best and most extensive source on interplanetary travel in Battletech is Strategic Operations. It goes into depth on the functionality of jumpships and gives hard numbers on things like recharge times and orbital transfers.
@melvinlemay7366 Huh! Maybe I should grab a copy, run a campaign or two to get a feel for it. I absolutely love the level to which they thought this out!
@@thevoiceofiron Just be warned, the rules laid out in stratops are very unintuitive and difficult to learn as they are presently presented. I love it as a lore book, but as a compilation of rules, it is not so great. I would strongly recommend using megamek as a tool to help guide you through the learning.
The Zenith and Nadir points of star systems can operate as Lagrange points, where gravity is balanced or neutral for the KF drive to function properly. There are also Lagrange points closer to planets and their moons, annotated as L1,L2,L3 etc. Like where the James Webb telescope is orbiting. These points also exist throughout a system and move sequentially with orbiting bodies. The BT universe calls these 'pirate jump points '. This dramatically reduces transit times and are more difficult to defend, however larger strategic systems often have Castles Brian defence networks or analogs within these vectors. The fusion drive systems of dropships / warships can burn into position with as much haste as the crews can tolerate the G forces.
I'm pinning this comment because it explains even more about how the FTL works, thank you!
To add on to that. Pirate Points are also more dangerous to Jump to as their location relative to the system as a whole moves more. Making a FTL jump to one having a higher likelihood of failure. Which is another reason why, outside of pirates or certain wartime attempts, they are avoided by most.
An important fact about those "pirate points" is that very up to date info on orbitals are required to properly jump there. And by "up to date", usually under a century or so. In other words, the time it takes for light to go from a star system to another one would make that data too out of date to use. It makes jumping to those points rather dangerous.
The advantage of zenith and nadir points is that they're equidistant from any planet in the solar system, since the orbits of planets around stars will tend toward a flat disk (just the result of conservation of rotational momentum in 3 dimensions). It's *technically* possible to jump to any point outside the gravitational proximity limit of the star (about 10.2AU for Sol), but there'd be little point in it. Strategic Operations (StratOps) page 132 has a great image showing all that off.
Dropships usually transit at 1G acceleration. It's possible to go faster, but human bodies don't do well at 3G or more for extended periods of time. StratOps has a table on page 70 detailing the time it takes to travel different distances under 1G acceleration. BT's dropships can go from Earth to the moon in about 4 hours (minus time taking off). On closest approach to Mars, they can go from Earth to there in 1.75 days. From Earth to the Sol Nadir or Zenith points is 9.1 days.
But the biggest time sink for jump travel in Battletech is waiting for the KT drive to recharge. There's a table in StratOps on page 87 that details how long it takes to recharge, depending on star type. These follow the same Stellar Classification system used by astronomers; our sun is a G2, so it would take 183 hours to recharge at Sol.
I'd suggest finding Strategic Operations. It has all kinds of info on how jumping works, and the timeframes it calls for. Sorry for the walls of text.
And on a minor note, our current tech can get us to Mars at closest approach in about six months. Venus would be half that time.
@@Xeno426 one thing i have loved about battletech fans since the 80s ... we love our game, we love science, we love understanding the military industrial complex, we like out fiction to make sense, we understand that comstar uses a lot of the 'old soviet method' of diplomacy, we get that humans will human and a happy go lucky universe / setting just is not going to truly happen with humans involved. do not need aliens. -(we are not going to bring up the bird man incident)- humans can cause enough drama intrigue plot and horror on their own.
@@catboxvideo I liked how at the start of the Clan Invasion (yes, way back in the day) it was thought that these invaders were aliens at first. And functionally they were with their different and unfamiliar ways of doing things. Which highlights you don't need actual aliens as even humans can be very alien to each other.
Dropships usually travel at constant 1g acceleration, speeding up towards their target on the first half of the trip, than reversing and slowing down for the second half. This is done to provide artificial gravity for the crew of the ship. When they need to get to places in a hurry drop-ships can accelerate above 1G, but naturally this is uncomfortable and even dangerous to the crew, so it's done only when speed is critical, but even then we are talking about 1.5G maybe 2G.
It is absolutely fascinating! You know, I'm so used to seeing the Leopard in MW5 and just walking around it between missions that I hadn't really thought too hard about the gravity... but that makes perfect sense!
@@thevoiceofiron So, one thing that the games tend to get wrong is how the aerodyne dropships (like the Leopard) don't have VTOL capability. They have to land on clear ground.
An interesting aspect of aerodynes is that their transit drive engines are on the bottom. This leads them travel to the planet with the "top" facing the direction they're going (rather than the nose). Otherwise the internal space of the dropship would have to be able to rotate about 90° so that "down" was beneath them rather than on a wall.
Spheroid dropships don't have this issue, since their transit drives can be the same, or in the same location, as the regular engines. "Down" is always towards the engines. However, in atmosphere, spheroid dropships are more vulnerable to aerospace since they can't maneuver as well.
@Xeno426 Very fair. I'd read that somewhere, and I tend to write off at least the Player Character's Leopard having VTOL/Hover capability as some kind of modification since you're a merc company... though that's admittedly cope, since I can't make excuses for having the enemy dropships do it, too, lol.
The heavy restrictions on FTL in BattleTech is what makes it so interesting. It's like Sanderson 2nd Law of Magic; limitations are more interesting than capabilities. Those limitations are basically what allow BattleTech to exist in the form we know.
Heck, the lack of artificial gravity is another big aspect. Dropships only have "gravity" when they're in transit to planet, or landed. In all other conditions (including halfway to their transit point) the people inside are under microgravity.
Jumpships and warships tend to have "gravity decks", which are just decks that spin like in 2001: A Space Odyssey. This provides places for people to hang out under 1g or similar conditions (some of the smaller grav decks spin slower and only generate ~0.8g, still enough to help prevent all the bad things from being weightless).
You know, I've often said "If you want to be truly creative, put yourself in a box!" for this very reason! Introducing rules to something makes it feel more consistent, more alive!
@@thevoiceofiron It's also true for jumpship and warship design. There's rules for how those work, which leads to BattleTech's space ships trending towards a specific look. Because the KF drive jumps things in a bubble, the most efficient use of space is a long rod (to maximize the sphere's diameter), with everything that needs to jump fitting along it.
@@Xeno426 Nope, the jump field is not a bubble. in fact, dropships have to be connected to the jumpship to extend the field around themselves (heaven help you if the K-F boom is damaged). anything within 2km of a jumping ship will be damaged.
Indeed
Excellent job with this video. I'm glad that your most rough bit of lore knowledge from the first video has been improved upon 😊
Me too! I love learning about settings!
Deep dive on warships. Those will not only impress you with the "golden age" in battletech. They will also horrify you on the level of deployment and destruction they caused.
Great video. Looking forward to seeing more!
Sounds like something I should look more into for sure!
@@thevoiceofiron You might want to look up the Age of War, the Mackie, and Tintavel. Each of these form the steps to why Battlemechs became a thing, but its due to the sheer destructive potential of Warships themselves.
They cause so much devastation that the Houses had to come together and sign what's called the Ares Convention.
Ponder on that a second, Houses constantly going to war with one another had to sit down, take a breather, and say "Okay I think we're going a smidge too far with our fighting".
THAT is how deadly warships were.
Also in terms of Dropship speed, it's always less than the speed of light. Since all the space ships in Battletech don't have artificial gravity like a Star Trek or Star Wars ship, they control gravity via thrust or rotation. We're basically playing with 2001: A Space Odyssey rules. Most Dropships like to go a speed to simulate 1G of thrust when they make their way planetside
@@Atlas3060 Very fair! Maybe I'll do a deeper dive into those on the channel at some point... but I love the depth Fasa put into all this!
The issue with 'sunbight' speeds in BattleTech is that most space craft list acceleration as there is very little resistance to slow you down or fight against, speed is kind of not a needed thing.
in example an Overlord class drop ship has a safe thrust of 1.5 g's and max thrust of 2.5 g's, but really in space 'speed' is not a number it keeps going up with continual thrust and as drop ships approach a target point - jump ship, moon, planet - they rotate and use their thrust to counter their own momentum and - in case of planetary landing - gravity OR in docking slow and use maneuvering thrusters to dock.
Transit time is liftoff to dock plus jump undock to landing, BUT if you need to make multiple jumps the recharge time can be a bitch. Depending on the jump sail (solar collector) and the stars strength. Some Older / New jump ships had a battery that would allow a second jump but these were included in tech that was bombed out of the setting for a long time the most part. to travel great distances in a hurry you would need a 'pony express' style of routing but would have to be a Major power or stupidly rich to have that many jump ships available to you - otherwise it is jump maybe wait a few days or week plus then jump... and on.
Warships on the other hand had Jump drives and large sunlight drives and would deliver their drop ships much closer to target as well as having some serious fire power. Again, bombed out of the setting for a long time.
Lastly, there are 'Pirate Points' that are closer to planetary bodies, buuut a lot more dangerous due to gravity, debris, etc.
Batteltech really did try to build in some realism to their setting of stompy robots. Now GM just needs to get it in gear, their reactors were due a couple years ago.
That's what I love about the setting: Enough rules to play by and really make the setting feel alive! After all, if there are rules, you can build strategy around those rules, and the more detailed the tech, the more brilliant the writers can show the strategists to be! It makes for good writing and good reading!
Also, yeah, wasn't GM supposed to invent the Fusion Reactor in 2022?
Keep in mind that "g's" are a unit of acceleration. So when a description says the max thrust is "1.5 g's", they're saying its max acceleration is 1.5 m/s^2, not its speed.
FTL in BT--though they call it a hyperspace jump sometimes--is closer to a quantum jump. The KF drive is basically a big capacitor that discharges after every jump. Unlike a capacitor, you have to trickle charge it so you don't break it, hence the energy sail. You can, in a pinch, use the fusion drive of your JumpShip to do it, though. The space magic really comes in the military DropShips which sustain a 1g acceleration and somehow miraculously use only about 21 grams of hydrogen fuel per second. A DropShip drive's output is measured in terrawatts. The fact it could power a small planet is quietly overlooked. Can't have a DropShip captain retire and become the planetary utility company when they should be transporting troops, after all.
Fair enough! I actually like that it's so complicated, or rather so energy intensive, as it grounds the setring in my eyes, and explains why the Inner Sphere is essentially the limit of Human expansion (...mostly) a thousand years from now.
Thank you for sharing 😊
That's an important clarification.
I'm nee to your channel & will subscribe for more BT rules & lore.
Thanks! I'll have to do some BT readings soon then!
One addition I would note that contributes to the travel time in the large scale of things: The KF Drive basically depletes it's charge after each jump so Jumpships and Warships can't make another jump immediately after. Instead they have to deploy energy collector sails to slowly recharge the dive, and alternatives to this process are limited as charging the drive too fast can actually damage it. The only ways to mitigate this limitation I can recall are recharge stations, which have their own energy collector sails and store power that can be transferred to a Jumpship or Warship to charge them faster, and Lithium-Fusion Batteries, a expensive and advanced piece of technology that lets a KF Drive hold a 2nd jump charge.
Ohh, very cool! Maybe one of these days, I should just read the full SARNA article on K-F drives/Jumpships on the channel. I love that FASA went into such detail for things like this, it makes the setting feel alive!
The below is based on Dropships and Jumpships by FASA. If there is a conflicting source, by all means pipe up.
Jumpships have 2 ways to charge the drive. the sail or use the onboard fusion reactor. using the sail is preferred to cut down on fuel expenses. Sail deploy time100 minutes, retraction 150-200 minutes. the sail will charge at a rate dependent on the system's primary star (151-210 hours) . A recharge station can beam extra power at the sail to accelerate the charge rate. There is a maximum safe charge rate. charging in under 150 hours risks damage to the drive.
The minimum safe distance to jump into or out of a system while avoiding gravitational influence is essentially a sphere. Presumably with minor perturbations for any VERY large planets. the radius of the sphere varying with the star type from as little as 0.07AU to as much as 347.84AU. The standard jump points are called the Zenith and Nadir points (North and South poles of the sphere with the plane of the planetary orbits defining the equator. These will be where any stations and commercial traffic will be.
Pirate points are NOT Lagrange points. Those are something completely different. Planets are not in the exact center of the system. In the case of very large stars they can be very far from the star (Earth of course being at a distance of 1AU). If you jump to a point on the jump limit sphere that is closer to the planet then the standard jump points then that is a jump point.
The Jump itself is not quite instantaneous. ( lightyears travelled/2 ) seconds plus a few seconds at each end for the field to expand and contract.
Ok, Skimmed the Hyperspace travel section of Strategic operations for changes. and some things have changed.
Lagrange and 'transient' points are now valid for jumps.
the minimum amount of time to safely charge the drive without risking damage has risen from 150 hours to 175. Mind you this change now means that almost half the star types on the charging time chart (ranging from 151- 210 hours) now charge faster than the drive can safely handle. Hopefully there is a way to throttle the charge rate
jump ships now have the option to dock with a recharging station to recharge directly. And if then want to charge the drive and a LF battery at the same time they can SOMEHOW use their own sail while docked with the station (which would typically have it's own sail). How the sails. don't get tangled I don't know.
and the jumps now take longer (light years traveled)/2 * (max dropships the JS can carry)
sail deploy/retract is a little faster now at 80 & 160 minutes
@@b.s.864
When it comes to throttling the charge rate it seems like it's something that could be doable somewhat easily. In theory you could: disable the power connections to some sections of the sail so you reduce the overall power intake, have a system that diverts excessive power to other ship systems, "vent it" via an emitter of some kind, or regulate power intake by only partially opening the sail.
As for how the Charge Station and Jumpship sails avoid being tangled that one also has some possible explanations.
1: Have the orientation at which the Jumpship docks at the station NOT be parallel to the axis that the station deploys it's sail. If the station sail is basically hanging far "above" the whole thing like the top of a mushroom then a Jumpship docked at a 90 degree angle to the station's central axis (making kind of a T or cross shape) can easily deploy it's sail out of the way.
2. Although they are called sails energy collector sails aren't sails in the traditional sense. They are catching small amounts of various forms of stellar radiation, such as solar light, over a wide surface radius. However when the extend out they are not being "blown" they are simply being moved to a extended position by completely mechanical means because they work most efficiently in that shape. To my understanding the radiation doesn't "blow" or really move them around in any meaningful way, they just sit where they were deployed and do their thing, only moving as a reaction to kinetic impact on either themselves or the thing they are attached to. So it should be fine so long as the sails are not literally deployed into one another.
@@Zanedor if the sails of a docked JS are deployed in a T orientation then they are not pointed at the sun and thus not charging anything. The sails on a JS are usually well over a km (tro2750 & tro3057). TRO3057 lists a recharging station with a sail 4km across. docking arms allowing a co-axial orientation would be impractical. While they call it docked, perhaps they really mean just a really long extension cord?
I agree that throttling charge rate is probably not an actual issue.
I have always been unsure which way the station keeping drive would be pointed. The standard jump points are incredibly far from the system's sun but are not in orbit of it. do they point away from the sun to counter the photon pressure on the sail. or toward the sun to counter the sun's gravity. does it depend on the stellar class? given these are small by true solar sail standards I imagine toward the sun is more likely.
Exactly.
Fun topic. Love the hard scifi of the setting, no artificial gravity, no shields, heavily limited FTL.
Think the FTL needs to be boosted to 60Lightyears
As the time to charge is insane, you looking at 7 days minimum 8 or 9 max… for every 30 light years is just not feasible
Meaning that a single jump will take you nearly a mounth if not more garenteed, and more jumps ad on another weak…
Yeah... though, the games at least seem to take this time into consideration, given how long it takes you to travel from one system to another.
That charge time is the safe and normal charge time. Setting has rules for doing things like trying to speed charge the drive, or having a giant battery to let you jump in sequence.
For large scale military operations there's also a 'command circuit', where you station JumpShips at each stop along the route. Then the Dropships just keep changing JumpShips, resulting in much faster transit while keeping the charge time consistent. Basically a FTL bucket brigade.
7 days is nothing. Transit times from jump point to the planet can be a real bitch. There are systems where it takes *40* days! You can do 4 jumps in that time and be 120 lightyears away before Dropship traveling to, say... Zaniah, lands there.
@@FrikInCasualMode Absolutely bonkers. But! That just makes the setting feel more... real, at least in my book!
Oh hard figures for dropships is easy standard burn is earths gavity worth of thrust. If your
2G is your battn down the hatches, every one seated for days of journy with some rest stops between.
Under 3gs is typicly maximum safe thrust and this is done for maneuvering, say your attacked. Folks have a chance of blacking out once your whipping it at 3g.
These can all be entered into a an equation to find times from planet to nadar and zenith.
All dropships are capable of 2g burn, and this is used to calculate times for travel, typicly at 1G, so tjat you can simply divide your time by 2 if your not doing mech maintenance in your travels.
Jumpships on the other hand can never reach such velocities often maxing out at 2g its most common for them to burn at just below 1g as alot of there time is simply making gravity and waiting for a jump. Having to then slow to a full stop to then make the jump and repeat.
Ah! Thank you!
I may have to go look this up, but the dropships tend to have thrust rated in gravities, I think 1-2 is standard?
That may make calculating the speed easier, yeah! I didn't see that on SARNA when glancing for this mini-rant, but then, it was a mini-rant not a reading, so maybe I missed it? Either way, makes sense!
@@thevoiceofiron You can find the values there in the sidebar on the right under safe thrust / max thrust, with 1.5g-2.5g being the average values for both dropship or warship (of course you've got exceptions to that). Jumpships usually have what they call a station keeping drive that's rated for 0.2g. Amusingly enough, in contrast to the more down to earth FTL, the sublight engines are pure space magic along the lines of 1950s scifi torchships.
@@jochenwenzel8878 Good to know, thanks!
@@thevoiceofiron Dropships and Aerospace fighters have thrust values. Two points of thrust means 1g of acceleration. A Union dropship(the default big sphere) is a 3/5, so can safely go 1.5gs and push it to go 2.5gs. A Leopard (the small plane like DS) is a 4/6, meaning that it can go 2gs without much strain on the engine.
Eyeballing it the fastest fighters seem to be able to pull 10gs of max thrust, although these are standouts. Fighters or Dropships with over 6gs (8/12) are rare.
Peak Star League tech had sufficiently functional AI for warships. While any AI that went through a Jump tended to go crazy, they made great system defense craft as they could maintain and adjust with thrust that would kill a crew.
@@jochenwenzel8878 pure magic? Nonsense. They are fusion mumble mumble mumble water reaction mass sometimes mumble just don't look closely mumble mumble
It's not so much that K & F could not practically test their theories at the time. It is more that their theories rejected Einsteinian relativity and institutionalized academia intrenched itself, rejected them, and turned them into pariahs the stigma for which lasted a century until a research team replicated some of their experiments and validated their theories by happenstance. Which is potentially some interesting commentary on academia as an institution.
Traveling between jumpships and planetary surfaces can vary quite a lot based on dropships used, solar system layout, and urgency. If it's just a routine flight, dropships will usually burn at 1g straight through accelerating to the half way point then flipping and decelerating the rest of the way. This is a *very* fast form of interplanetary travel which predominantly uses Hohmann transfers were you use orbits and gravity to coast around instead of burning straight through. These "turn and burn" maneuvers are the most common orbital transfers used in BT. Many system/planetary pages on sarna give transit times between jump points and planets and it is this maneuver they assume. Typically the times can range from 5 days to 2 weeks from what I've seen, though I haven't done an extensive survey to find a representative average or range. However, sometimes faster operations are necessary. Important political travel can often bump this up to 1.5 or even 2g. Military operations will frequently preform these transfers using the maximum safe thrust of a dropship. From what I've seen this ranges between 1.5 and 3g.
The best and most extensive source on interplanetary travel in Battletech is Strategic Operations. It goes into depth on the functionality of jumpships and gives hard numbers on things like recharge times and orbital transfers.
@melvinlemay7366 Huh! Maybe I should grab a copy, run a campaign or two to get a feel for it. I absolutely love the level to which they thought this out!
@@thevoiceofiron Just be warned, the rules laid out in stratops are very unintuitive and difficult to learn as they are presently presented. I love it as a lore book, but as a compilation of rules, it is not so great. I would strongly recommend using megamek as a tool to help guide you through the learning.
@@melvinlemay7366 Fair enough!