Is there room in the BTu for alternate forms of FTL?

[Daemion]

So, once they figured out how the Hyperpulse worked and rigged a system for ships, any advancement into other versions of FTL probably went into a closet somewhere and got burned up in an ensuing conflict.

However, some other science fiction genres like to use wormholes and linked systems.  In Heavy Gear, for example, these portals are based on certain gravity-based distortions, and some of the systems, like Caprice, would have been skipped over for garden worlds that could be jumped to directly in BT's timeline. 

But, could they also exist in the BTu? 

Then, there's warp drive.

There's also the possibility of extended periods in sub/hyper space like in Babylon 5 and Warhammer 40k. 

So, do you think it's possible in the fabric of BT reality? And, if such things were possible, like gate-point travel, what kind of effect do you think it might have when first discovered, versus later when it became common knowledge?

I personally think pirates would have a hayday using gates that nobody thought to look for while conducting raids.

Thoughts?

[RunandFindOut]

The JumpDrive is at the core of the feel of the setting.  You start introducing multiple FTL systems and it might as well turn into any old generic sci-fi.  The one change I have ever done with FTL and I haven't done it in a long time was done to make some of the early setting material and the "cattle-raiding" of the 3SW make sense.  With the scarcity of Jumpships in early sources and how some of those early sources talked about some of what later became known as the Dropships as having been used as 'warships' by the Star League or Houses.  Well I was faced with the question of how exactly all those small raids were happening all over the borders?  So I came up with a 'small jumpdrive' that could be mounted on Dropships to make the prevalence of small raids less headscratching.  Initially they didn't have a weight as there wasn't really much of a construction system for aerospace stuff at the time (though later I would make them 5% of the weight of the Dropship).  These 'small jumpdrives' allowed a Dropship to make a single 1LY jump every 24 hours and didn't track fuel consumption.  (Reasoning was that if proper Jumpships could make a 30LY jump with what amounted to a few MW of solar energy collected over a week then making it consume lots of fuel was just pointless).

[iamfanboy]

Well, most FTL scifis posit only one method of interstellar travel. It's either 1) slipping into a nearby dimension where the distances between points are shorter and then popping back in when you get near where you want to go, 2) warping space so that the distance between point A and point B is shorter, or 3) outright folding space so that two points touch, and then transitioning yourself to the other point before unfolding space. Battletech is, technically speaking, 3. Instant jumps don't fall under 1 or 2.

And I'm okay with that. A scifi universe should make at least a semblance of internal sense. Warp 10 is never going to be possible in the Star Trek universe; it's always 9.938739983 or whatever. Star Wars hyperspace objects can only be affected by normal universe gravity, not turbolasers or Force lightning.

The idea that in Battletech the physics are "maximum jump range = 30 light years" is something that is a constant, and it lets you play with the variables.


What I'D want to see is Sub-compact WarShip cores made common. A mix between DropShip and JumpShip, sized for a group of RPG players to maybe carry some light cargo between worlds, touch down with a few 'Mechs, and generally close up the hole that has always existed in universe. Maybe make them expensive, make them small enough that they simply CAN'T replace the bulk carrying capacity of a proper JumpShip/DropShip pair, but put them IN THERE.

That would change a lot of paradigms in itself. Small bulk, high-value items like datachips and tech gadgets would be more common to sell and spread across the galaxy, raising trade and creating a more modern, unified society. Pirates might adopt simple, tiny-scale thefts rather than massive raids. The value of ASFs and combat spacecraft would raise as well, because it would be the only way to protect a world - without diminishing the value of BattleMechs, because boots on the ground = real power.

[idea weenie]

One thing to take into account is limitations on the FTL system.  For example, nBSG had the capability for a ship to jump into orbit and start dropping nukes, with little or no warning.  If you have an FTL system that lets people pop into orbit over a planet, then the goal of planet-based people should be to get a ship so they are no longer a potential target.

Traveller had a system where you needed fuel to travel X distance (measured in parsecs, 1-6), plus you could only arrive up to 100 diameters to the target body.  You could arrive farther, but that 100 diameters was the minimum range.  This allowed for there to be front lines in a space war, and made supply lines close enough that any attackers and defenders had to deal with potential raids.

Halo had slipstream that is a very violent environment, and required lots of math to make it work.

Star Trek warp drive appears to be safest if you exit it near the edge of a system (based on Best of Both worlds where Enterprise came out of Warp at the edge of the system vs nearer to Earth).

The Honorverse has the alternate dimension, where you can only exit where the gravity is low enough, and at or below a certain speed to arrive safely.


B5 hyperspace requires the ship to have to thrust to enter, move, and remain stationary relative to a destination, imposing a fuel requirement on ships.  Advances in sensors mean ships can travel farther away from the beacon network (freighters have to stay close so avoid losing the beacon or they are lost forever, warships can detect the beacons from farther away).  If a pirate group was using a forgotten gate, they would need to make sure the beacon was only on during times they had pre-arranged, to make sure nobody else detected or decided to use the beacon.  The pirates would also need to use fuel while traveling, so the more picky in loot they are, the farther away they are (too much of their mothership is taken up by fuel tanks to return, so they simply can't grab everything they want).

[greatsarcasmo]

In the "Humanity, ****** Yea!" Jenkinsverse saga, there's a warp like FTL as well as a point-to-point wormhole jumping system that relies on beacons to anchor the wormhole. There are also shields that can protect a work/solar system from both types of FTL. I kind of like there being multiple ways to beat light.

[Natasha Kerensky]

There could be more than one FTL drive or technique in BT as long as they all obeyed the same stellar proximity limits and planetary pirate point limitations as jump drives.  As long as FTL drives cannot zip or blink around inside a solar system, there's not much impact on BT play. 

At the level of the BT universe, I suppose a non-instantaneous FTL drive would put its faction at some disadvantage versus factions with the BT jump drive due to slower travel and response times.  That could affect multi-planet campaigns, economies, balance-of-power, and such.

But if both types of FTL drives still have to send in the dropships once they arrive in-system, it's not going to change most planetary assaults or raids.

Traveller had a system where you needed fuel to travel X distance (measured in parsecs, 1-6), plus you could only arrive up to 100 diameters to the target body.  You could arrive farther, but that 100 diameters was the minimum range.  This allowed for there to be front lines in a space war, and made supply lines close enough that any attackers and defenders had to deal with potential raids.

I don't recall those specific rules, but conceptually, I loved Traveller's Stutterwarp Drive.  The macro-scale electron tunneling had the whiff of scientific reality.  The drive's need to discharge was a good strategic limitation.  And the drive slowing to sub-light speeds inside gravity wells was a good tactical limitation, allowing for very high-speed, but still causal, space combat.

Not to knock jumpships and dropships, but stutterwarp remains my favorite FTL concept.  I wish it had been incorporated into a more popular/better sustained scifi setting/combat system.

[SCC]

One thing to take into account is limitations on the FTL system.  For example, nBSG had the capability for a ship to jump into orbit and start dropping nukes, with little or no warning.  If you have an FTL system that lets people pop into orbit over a planet, then the goal of planet-based people should be to get a ship so they are no longer a potential target.

BT already has this, what do you think jumping in at the planet/moon L1 point is?

[guardiandashi]

there is no inherent reason another form of FTL couldn't coexist with battletech's Jump drives as long as it has similar limitations for instance lets break down the cannon Jump drive

1 it requires a significant mass fraction of the ship
2 it takes significant time to charge (or cooldown) depending on how you look at it.
3 it cannot be used under too high of a gravitational gradient
4 the actual operation of the jump is for all practical purposes instantaneous for distances up to 30 light years.

so if you come up with another form of FTL drive it should have similar net effects
for example if you say that the cooldown/charge time between jumps (safe) is 7 days, then what ever new drive you introduce should not have an effective top speed more than ~30ly/7days or around 4-5 ly/day if you are basing it off something like LF jump system then ~9-10 ly/day should be the maximum speed.
it should require a significant portion of the ship to be the FTL drive unless its an "addon" to a sublight drive but even then the drive mass should be comparable to a jump and in system drives total mass.
it should have some restriction keeping you from coming screaming in at ftl speeds until you are right on top of the destination planet unless you are willing to accept significant risks of sudden death without harming the target. (or you have someone who will use it as a WMD )

it should require some form of fuel or "rarium/unobtanium" for construction to explain why these things aren't all over the place.

ETC.

[Phobos101]

Reading this made me wonder if, in the event of the loss of a number of JumpShips, maybe one of the successor states would have made an effort to convert some of their remaining KF drives into an end to end system of "gates" or something similar, allowing non-KF equipped ships to make jumps between a limited number of critical systems. Although this would drastically limit their jump capabilities, It would allow centralised maintenance and defence. Maybe an AU idea for a rainy day?

[Nightlord01]

Reading this made me wonder if, in the event of the loss of a number of JumpShips, maybe one of the successor states would have made an effort to convert some of their remaining KF drives into an end to end system of "gates" or something similar, allowing non-KF equipped ships to make jumps between a limited number of critical systems. Although this would drastically limit their jump capabilities, It would allow centralised maintenance and defence. Maybe an AU idea for a rainy day?

Gates can't work, but you could use a type of shuttle, the Ryan Ice Cartel managed to refit jumpships so that three of them could lug along a massive chunk of ice, but gates are no go as the drive itself jumps, it just happens to take everything with it.

[Red Pins]

The JumpDrive is at the core of the feel of the setting.  You start introducing multiple FTL systems and it might as well turn into any old generic sci-fi.  The one change I have ever done with FTL and I haven't done it in a long time was done to make some of the early setting material and the "cattle-raiding" of the 3SW make sense.  With the scarcity of Jumpships in early sources and how some of those early sources talked about some of what later became known as the Dropships as having been used as 'warships' by the Star League or Houses.  Well I was faced with the question of how exactly all those small raids were happening all over the borders?  So I came up with a 'small jumpdrive' that could be mounted on Dropships to make the prevalence of small raids less headscratching.  Initially they didn't have a weight as there wasn't really much of a construction system for aerospace stuff at the time (though later I would make them 5% of the weight of the Dropship).  These 'small jumpdrives' allowed a Dropship to make a single 1LY jump every 24 hours and didn't track fuel consumption.  (Reasoning was that if proper Jumpships could make a 30LY jump with what amounted to a few MW of solar energy collected over a week then making it consume lots of fuel was just pointless).

Actually, there was a thread, quite a while ago, where this option was brought up - I can't remember who, but think he was the same one to note the potential of WiGE vehicles to be dropped at high altitude and descend to normal height safely.

It was interesting because it reduced the investment costs so significantly, essentially turning a PWS into a major combatant, and the potential of raid-oriented warfare getting out of hand.

[SteelRaven]

Very few Sci-fi universes use more than one forms of FTL travel simply for simplicity.

Plus the more holes you punch in realty (the only way you can describe FTL travel when you think about it) the less believable your universe becomes.   

[Domi1981]

Why? ???

[Charistoph]

There could be more than one FTL drive or technique in BT as long as they all obeyed the same stellar proximity limits and planetary pirate point limitations as jump drives.  As long as FTL drives cannot zip or blink around inside a solar system, there's not much impact on BT play. 

Very few Sci-fi universes use more than one forms of FTL travel simply for simplicity.

Plus the more holes you punch in realty (the only way you can describe FTL travel when you think about it) the less believable your universe becomes.

Not necessarily.  Star Trek offers several different ways of getting around from the ubiquitous Warp Drive to Trans-Warp tunnels to wormholes.  Stellaris is very similar going with tunnel drives, jump drives, and wormholes (both natural and manufactured).   All have their own rules and require certain levels of technology in order to justify their use.

Firestorm Armada is very interesting, and I think could very well apply here.  Most fleets use a Fold Space Drive (FSD) for normal transits.  This is because it offers the most efficient means of transport.  There are wormholes and one can even manufacture wormhole gateways in this universe.  The problem is that they cannot operate anywhere near a star, like measured in light-weeks to light-months distant (I'm not totally sure of the distances needed myself).  Add on to that is the fact that a FSD is completely incompatible to using these wormholes.  So, you would need an FSD to reach the wormhole, but then you would need to change ship in order to take advantage of it, then change ship again on the other side to use the FSD, if you wanted the fastest possible transit time.  Most times, it is just easier and more efficient to go straight there on FSD.

Starfire, Descent: Freespace, and Wing Commander utilize points in space that ships can jump through with very little fuel and mass cost (most shuttle-size craft can carry it, and Freespace fighters carry such devices).  These ones are provided the narrative challenge that these points can appear anywhere in a system, but cannot be transited outside these nodes, making them more like train tracks than anything else.  These points can be hard to detect when you have the sensors and knowledge to find them, but if you don't *shrug*.

In other words, such wormholes, jump points, and the possibility of gateways may be fully possible in the BT universe, the problem is that they are so completely outside of any reasonable transit range to be of any practical use to anyone.  No one in the BT universe really transits past a system's oort cloud, which could posit they exist.  Even if you knew they existed, what's the point of using one if you need to do a 4+ month transit to reach it, and then take another 4+ months to reach your target system when Jump Ships could make it in 3 or less and have people around (in most cases) to help in case of emergency?

[idea weenie]

BT already has this, what do you think jumping in at the planet/moon L1 point is?

That reduces the time to hours, but it still requires the attacker to orient and launch bearings only missiles in drift mode to hit the planet.  That would still give the defenders a little time to react.  It also requires good math on the attacker's part to get the location correct (i.e. dedicated attackers can use it, casuals have to come in at jump points).

I'm talking about similar to nBSG where the Galactica is capable of jumping into upper atmosphere, or how the Raptors can jump into low atmosphere.  If a ship jumps into LEO, it is too late for the defenders unless they have an obscene number of orbital and ground based defenses.  If the attacker is capable of jumping directly into the atmosphere, they can salvo launch nukes and jump out before the defenders can do anything.

[Garrand]

I think introducing something like wormholes into the Battletech setting would fundamentally change the "feel" of the setting, since it would start to introduce the complication of time travel to the setting. The most logical way I've read about how to create wormhole "highways" would be to create one in the starting system you want to connect (like Terra FREX), then load the exit mouth onto a dropship & blast it off towards the destination at a constant acceleration. You could duct fuel to the drive via the wormhole, so its not necessary to carry enough fuel for the journey. But the issue is that it would be at sublight speeds, so it could be several decades to hundreds of years to start linking systems together in a local neighborhood. Wormholes however will want to keep the timeframes of both ends consistent, so what happens is that the journey from the entryway will seem to only take months (due to time dilation), but the actual physical journey will be hundreds of years into the future. Thus anything that goes through the wormhole will travel hundreds of years into the future (or into the past if going the opposite direction). I think that would mess with the setting too much.

Also IIRC the mouth of a wormhole has to be kept open using matter with negative mass, and I don't know if such a thing could exist in the setting...

Damon.

[Dayton3]

I thought much of the Battletech jump drive system was specifically designed so that in universe there was very little opportunity for space combat.    As in you won't see starships pursuing each other and engaging in battles at FTL velocities.

[Maingunnery]

I could see room for KF Booster gates (for longer jumps), these would then become vital points in deep space.

[iamfanboy]

So there's one serious problem with faster than thirty years in a jump (expensive KF batteries aside), and that's how it changes the defense paradigm of the universe. It would be nigh-impossible to defend more than a fraction of your worlds against serious attack, and it would be a problem that ALL factions would have - sure, Steiner could jump in and wreck up Twycross with barely any warning, but if Clan Jade Falcon could hop over to Hesperus and destroy or take THAT with no warning, then it leads to a stalemate where feudalism and war literally become impossible.

Every nation would have large, quick-response forces gathered near their own gates that they literally COULD NOT USE because the moment one nation attacks a vulnerable planet deep inside the enemy's lines, then the other nations do exactly the same thing.

Even if the range was limited in some way, say to 120ly, that changes a lot - you'd have to constantly monitor your opponent's nearby worlds to make sure they weren't building the things to reach deep in your own systems, and you'd never succeed because they can always build them in uninhabited systems.

Space warfare would become paramount, and staging raids to blow up these hypothetical jumprings before they got used, or suicide missions to blow up the rings at the quick response force garrison to invade their underdefended planets, would be the most common aspects of warfare...


Now, I'm not saying that this wouldn't be interesting as a foundation to some other scifi universe (come to think of it, doesn't Mass Effect have something similar with the relay system?) But it's not BATTLETECH, which is giant robots blowing nine kinds of hell out of each other. If an in-universe development would threaten that, it needs to be removed, which is why we don't have WarShips any more.

[RunandFindOut]

Of course you can also change that by making the other FTL slower but more accessible than jumpship based KF.  That's what I did so long ago when I added dropship mounted jumpdrives to the setting early on.  You could only travel 1LY/24 hours, several times slower than a proper jumpship.  It made access to FTL broader and made the in-universe canon of small raids actually possible (because there weren't enough jumpships to support the kind of border raiding the early setting indicated was happening.  Jumpships were too rare and precious to be diverting so many of them on those small border raids.)  But at the same time it otherwise still operated under the constraints of KF drives, only slower.  So it didn't overly change the Strategic picture, the Houses were still limited by the transport bottleneck.  It just pushed FTL down where it was more broadly accessible so that the small raids already a canon feature of the setting made sense.

[Charistoph]

They can already do that by jumping through uninhabited systems.  That's how the Fox gave a surprise present to the Dragon when he faced the Jags on Luthien, after all.

[iamfanboy]

Of course you can also change that by making the other FTL slower but more accessible than jumpship based KF.  That's what I did so long ago when I added dropship mounted jumpdrives to the setting early on.  You could only travel 1LY/24 hours, several times slower than a proper jumpship.  It made access to FTL broader and made the in-universe canon of small raids actually possible (because there weren't enough jumpships to support the kind of border raiding the early setting indicated was happening.  Jumpships were too rare and precious to be diverting so many of them on those small border raids.)  But at the same time it otherwise still operated under the constraints of KF drives, only slower.  So it didn't overly change the Strategic picture, the Houses were still limited by the transport bottleneck.  It just pushed FTL down where it was more broadly accessible so that the small raids already a canon feature of the setting made sense.

With only one major problem: they don't exist. I mean, yes, it'd be a nice idea, and broadly similar to mine in getting interstellar travel into more hands.

Though 'constant raids' is probably overstating the issue, as it doesn't seem as though there were more than a half-dozen campaigns waged on each front every year, which fits with the logistics and equipment availability - 2,000 JumpShips (as per Dropships & Jumpships) at the time, with maybe 10 or 15 in use on any given front (on both sides) at any given time still gives a LOT of interstellar transportation. There are only 5 fronts, after all, that's less than 1/20th of them being used for combat operations!

Even the 4th Succession War's first (and biggest) wave only attacked NINE systems, and it's stated that doing it strained Davion's interstellar transport to the utter limit. If interstellar raiding (and thus transport) were that common, then what he did wouldn't be exceptional; he'd just have to break off the raiding and use those ships for more serious work instead.

While he probably required Monoliths and Star Lords to move the troops listed, only one or two of each per system would be required - and it's fluffed that Davion stripped his merchant lanes of JumpShips to make his move, so he'd sensibly use those big ships for the troops and save the smaller ones for the pony express and mail ships.

[RunandFindOut]

With only one major problem: they don't exist. I mean, yes, it'd be a nice idea, and broadly similar to mine in getting interstellar travel into more hands.

???It's a fictional universe.  What exists is whatever you say exists.

Though 'constant raids' is probably overstating the issue, as it doesn't seem as though there were more than a half-dozen campaigns waged on each front every year, which fits with the logistics and equipment availability - 2,000 JumpShips (as per Dropships & Jumpships) at the time, with maybe 10 or 15 in use on any given front (on both sides) at any given time still gives a LOT of interstellar transportation. There are only 5 fronts, after all, that's less than 1/20th of them being used for combat operations!

Even the 4th Succession War's first (and biggest) wave only attacked NINE systems, and it's stated that doing it strained Davion's interstellar transport to the utter limit. If interstellar raiding (and thus transport) were that common, then what he did wouldn't be exceptional; he'd just have to break off the raiding and use those ships for more serious work instead.

Here's the problem with that.  You're only counting large campaigns waged by the House ruler.  There's plenty of material from the early part of the setting of small raids being carried out by individual nobles, mercenary groups, corporations on their own.  In actions that do not appear in any of the listed campaigns yet were covered by written material and definitely happened in setting.  Where did they get the FTL transport for it?  There are too many cross-border raids in the early setting to be accounted for by the Jumpships they were supposed to be able to have at the time.  They were short enough on shipping that the biggest campaign of a Great House leader only attacked nine systems in his biggest wave in the 4th SW.  Yet once you start gleaning through the same early material you see mentions of dozens of raids occurring on each border within a fairly short time period.  Often not even by House forces but by individual merc units or the forces of various lesser nobles. 

It's just one of those things that didn't get much attention back when it was a beer and pretzels game at the beginning.  But my solution at the time ultimately worked to explain how so many small border raids could happen by small players that shouldn't be able to monopolize a jumpship without disrupting the setting overly much.  And that's all it really needed to do.  Just apply a more primitive and slower version of the KF drive that could be small enough to fit on dropships so that those small players could make their small raids.

[guardiandashi]

I think introducing something like wormholes into the Battletech setting would fundamentally change the "feel" of the setting, since it would start to introduce the complication of time travel to the setting. The most logical way I've read about how to create wormhole "highways" would be to create one in the starting system you want to connect (like Terra FREX), then load the exit mouth onto a dropship & blast it off towards the destination at a constant acceleration. You could duct fuel to the drive via the wormhole, so its not necessary to carry enough fuel for the journey. But the issue is that it would be at sublight speeds, so it could be several decades to hundreds of years to start linking systems together in a local neighborhood. Wormholes however will want to keep the timeframes of both ends consistent, so what happens is that the journey from the entryway will seem to only take months (due to time dilation), but the actual physical journey will be hundreds of years into the future. Thus anything that goes through the wormhole will travel hundreds of years into the future (or into the past if going the opposite direction). I think that would mess with the setting too much.

Also IIRC the mouth of a wormhole has to be kept open using matter with negative mass, and I don't know if such a thing could exist in the setting...

Damon.

re the "wormhole into the future... sorry it doesn't work that way
because people completely misunderstood what Einstein said.  yes there is some time distortion at c fractional speeds but the common misconception is that if you were to travel away from earth at 99 of the speed of light and then at some point you turned around and came back to earth everyone on the ship would have only aged months and decades or centuries passed on earth instead.
sorry that is not correct.  What actually would happen is that if you were pointing a telescope at earth your observational frame would make it appear that little to no time is passing on earth, while the ships clocks move at whatever rate they would move.  then when you turned around and headed back to earth suddenly time on earth would seem to rocket forward but the reality is that time on earth and on the ship were passing at close to the same rate (subject to any actual time distortion due to relative velocities.)

so the 2 ends of the wormhole are going to be effectively fixed in time relative to each other, with the only  time it takes to travel from one end to the other being the main change.

what Einstein was talking about had to do with frames of reference and observational time issues not actual significant time distortion due to travel.  (ie observational bias)

[MoneyLovinOgre4Hire]

You sure about that?  Because IIRC it does occur and results in among other things the clocks on satellites becoming desynchronized from clocks on the ground if they're not regularly reset.

[CrossfirePilot]

re the "wormhole into the future... sorry it doesn't work that way
because people completely misunderstood what Einstein said.  yes there is some time distortion at c fractional speeds but the common misconception is that if you were to travel away from earth at 99 of the speed of light and then at some point you turned around and came back to earth everyone on the ship would have only aged months and decades or centuries passed on earth instead.
sorry that is not correct.  What actually would happen is that if you were pointing a telescope at earth your observational frame would make it appear that little to no time is passing on earth, while the ships clocks move at whatever rate they would move.  then when you turned around and headed back to earth suddenly time on earth would seem to rocket forward but the reality is that time on earth and on the ship were passing at close to the same rate (subject to any actual time distortion due to relative velocities.)

Consulting "Relativity" by A.P. French (which was the Relativity text when I was a physics major). If I took a 99% lightspeed trip for about a hour so and left in the morning.  By the time I got back to earth. It would be evening.  If you have access to it, reference pages 97 and 154.

[guardiandashi]

You sure about that?  Because IIRC it does occur and results in among other things the clocks on satellites becoming desynchronized from clocks on the ground if they're not regularly reset.

I just looked it up, the GPS satellites run a little faster than on the ground.... a whole whopping 1.7 seconds per century

[Charistoph]

I just looked it up, the GPS satellites run a little faster than on the ground.... a whole whopping 1.7 seconds per century

My watch runs ahead faster than that, and I haven't gone through anything more relative than the planet has.

[RunandFindOut]

My watch runs ahead faster than that, and I haven't gone through anything more relative than the planet has.

Yes but your watch isn't a multi-million dollar piece of hardware designed to loose less than a second per thousand years either.  And that's the sort of thing GPS satellites use as timekeepers.  Just like CrossfirePilot I too remember that same example in the text of my one college physics class, though I can't exactly reference it as I sold that text a very long time ago.

[CrossfirePilot]

I just looked it up, the GPS satellites run a little faster than on the ground.... a whole whopping 1.7 seconds per century

Two things impact that.  Their velocity, which is a function of v^2/c^2 and that they experience less gravitational pull.

https://en.wikipedia.org/wiki/Hafele–Keating_experiment