Compact KF drives were not the hurtle the IS had with Warships?

[Icerose20]

Up until the loss of The Solar System to the Wobbies, Comstar was the only that could produce the maneuvering drives needed for the Warships.  Not the Compact KF drives.  (Not counting the Clans)  But they can make these drives for dropships?  What I do not understand is why the IS didn't start prototyping smaller 'warships'(up to 150K tons) during the time of late 3040s till they could get the handle on making the bigger drives.  Yeah, they might be inefficient against dedicates assault dropships, but rapid reaction force to planets that have minimal garrison would be perfect for these miniWarships.

Basically, use dropships engines that are already being produced or that could be modified and design a Warship around it. 

[Frabby]

I would rather interpret the data as thrust engines having been the last hurdle that was overcome; that doesn't say much about other hurdles such as compact KF drive manufacture or naval weaponry.

To me, the really fascinating in-universe aspect is that they designed new vessels from the ground up right from the start, instead of tipping their toes in the water first with established Star League era designs. I personally love the Fox-class corvette, but if I was in charge of the FedSuns efforts to build a WarShip then I'd have used a tried and proven design first that doesn't hold any nasty design errors. Something like the Mako or perhaps Vincent class.

[glitterboy2098]

given that compact cores are an older technology relative to the standard core, and that the IS never lost the technology to manufacture new standard cores, i suspect that they just needed data on what settings to input into the manufacturing lines. given they lost a lot of data on the actual physics behind the KF drive, they wouldn't have been able to work that out from base principles. the Helm core filled that knowledge gap, and probably had some details on the setting themselves.

Transit drives though they didn't have any infrastructure for. while they can build stuff for dropships, those are far smaller than the drives needed for even the lightest warship. and dropship drives would include a lot of features not needed for a warship (like systems to allow use in atmosphere, water landings, etc.), the removal of which would involve a substantial redesign of the engines themselves. and let not forget that the drives also provide the electrical power for the ship, which a warship would likely need a lot more of by tonnage than a dropship would, given things like the better sensors, stronger maneuvering thrusters, and possible presence of extensive energy weaponry (capital class or otherwise)

none of those are insurmountable hurdles on their own obviously, since they would all be stuff they could work out using existing knowledge. but the issue is one of scale. none of their dropship drive factories would be set up to produce drives as large as a warship would require, and it wouldn't be quite as simple as producing a bunch of small drives and strapping them together in a hull.

so i can believe that the transit drives were the last hurdle.

Comstar had maintained and even built new warships during the succession wars, and thus Terran factories for warship transit drives still existed, so them manufacturing the drives made some sense too. though i suspect that prior to Tukayyid and the Schism, the factories were under orders to drag their heels on production, to slowdown the successor state's warship production, which would not have suited comstar's long term plans.

[Daryk]

Not a bad argument, except for the Behemoth.  They absolutely could make engines for 100,000 ton ships that didn't land on planets.

[Liam's Ghost]

The problem with that is nobody was building warships small enough to use behemoth drives, and the fact that they had to go to Comstar suggests they couldn't easily scale up from that.

[glitterboy2098]

Behemoth drive system is 13,000 tons.
a hypothetical 100K warship with the same 2/3 thrust profile is 12,000 tons.
obviously there is something going on there that is different.
not that a 2/3 100K warship is going to be all that useful.

[Daryk]

More useful than no warship at all.

And why no one thought of it is certainly a mystery.  There's plenty that you can cram into a 100,000 ton warship that can't be installed in DropShips...

[Icerose20]

for a 100K ships, the 1K difference in drive size is just not that much to quibble about.  I wish i didnt lose my Battletech books my family has done.  So, what current book is the updated Warship construction rules at? 

[Liam's Ghost]

More useful than no warship at all.

And why no one thought of it is certainly a mystery.  There's plenty that you can cram into a 100,000 ton warship that can't be installed in DropShips...

Ooh, sounds like a design challenge waiting to happen.

[glitterboy2098]

Ooh, sounds like a design challenge waiting to happen.

only if you also limit it only to that hardware available circa ~3050
and include some judging criteria that discounts overly optimized designs.. (since the IS powers would not have had good naval doctrines or perfected the ideal weapons mixes and placements.. hell, even the hegemony never optimized their later stuff despite centuries of experience to draw on)

[Alexander Knight]

for a 100K ships, the 1K difference in drive size is just not that much to quibble about.  I wish i didnt lose my Battletech books my family has done.  So, what current book is the updated Warship construction rules at?

Strategic Operations.  And the fact that there is any kind of tonnage difference means they are not the same engine.

[Icerose20]

compared to the size of the craft, 1% difference is nothing. 

(Paid for the PDF of Strategic Operation, and they said no warship can be smaller then 100K tons, but I know the Bug-Eye, was 6100 Tons, so whats the deal)

[Frabby]

(Paid for the PDF of Strategic Operation, and they said no warship can be smaller then 100K tons, but I know the Bug-Eye, was 6100 Tons, so whats the deal)

The Bug-Eye didn't quite fit the rules even when it was first created (not that there were set-in-stone WarShip construction rules back then, which of course didn't stop FASA from pushing a TRO out the door...).
The Sub-compact KF Drive was then written into the rules to allow ships like the Bug-Eye to be built. But it's a fringe tech for a fringe design.

[Liam's Ghost]

The Bug-Eye didn't quite fit the rules even when it was first created (not that there were set-in-stone WarShip construction rules back then, which of course didn't stop FASA from pushing a TRO out the door...).
The Sub-compact KF Drive was then written into the rules to allow ships like the Bug-Eye to be built. But it's a fringe tech for a fringe design.

Actually, the Bug Eye could be legally created as far back as battlespace, which put a minimum mass for a compact jump core (not the ship itself) at... I think 2500 tons. It only ceased to be legal when Aerotech 2 and the revised rules were released, and only became doable again with the release of tactical operations (for rules on the subcompact core) and strategic operations (for the most up to date rules on jump capable vessels in general).

In a way, I've always been a bit morose about the change in AT2. I liked having the option of making sub-hundred thousand ton ships, and the subcompact option never really scratched the itch. But now we have primitive jumpships!

[Icerose20]

Well, My idea for a 'mini' Warship was around 50K tons, not 100K.  But i decided to try the 100K range.  Biggest problem with creating the Warship is, the rules for construction are spread around 4 books.   It used to be 2. 

Of course, I do not build Warships the way its suggested in the book.  Step one: size, Step Two: KF Drive; step 3: THE TOYZ;  (MWHAHAHA) Step 4, i need some armor don't I, Step 5: Yeah, I need a Planetary Drive.  Step 6: Adjust TOYZ.

[Vition2]

compared to the size of the craft, 1% difference is nothing. 

First of all it's closer to 7.7% of a difference (1,000 tons is not 1% of 13,000 tons). 

Second, that's a potential huge amount of difference, a cell phone from two decades ago while potentially nearly the same mass as a modern one had dramatically different capabilities.  Going even further back, a bronze sword, though nearly identical in mass to a steel sword will have vastly different properties.  Teching up even further just dramatically changes the potential that a certain mass can provide for whatever it is functioning with.

[Icerose20]

So the dropship drives are more inefficent then the Warship drives.   

USN doesn't us Nuke Power on every ship, even if they are more efficent then the Gas Turbine they use on almost every other class of ship. 

*****

Done

[glitterboy2098]

can you move the design over to the designs section of the forums? so the thread doesn't get moved around by the mods?

[Daryk]

It wouldn't have been a bad thing if the mods moved the thread... a lot of what we're discussing could be best illustrated by a design or two.

[Icerose20]

Its an interesting idea, and in some way explain how the house get to start building the far bigger warships. 

[Charistoph]

I would rather interpret the data as thrust engines having been the last hurdle that was overcome; that doesn't say much about other hurdles such as compact KF drive manufacture or naval weaponry.

Not necessarily.  The tech for Warship transit drives was basically a rejigging Dropship drives for the needed requirements.  In relative terms, its worrying about the screw design for your cruisers when you're used to building frigates.  Most of the principles are there, but difference in scale needs to be taken in to account and what few adjustments are needed for that adjustment.

In a way its saying, "First, let's figure out how to make sure the hull doesn't cave in under its own weight as well as repel the medium its going to operate in.  Then figure out how to support the massive engine/generator we're going to power the thing with, then we'll worry about the tech we know, but just have to modify to fit."

[Starfox1701]

Not really a rocket engine iis a rocket engine..... There's no manufacturing reason that's logical for the bottle neck. Its not like you are building the engine oon the ground and have to boost it to orbit. Also consider the tonnage of these things. Just how the hell you going to move one of them? Building them at Sol and shipping them all over the inner sphere makes even less since then the other houses not being able tto make them in the first place.

[Charistoph]

Not really a rocket engine iis a rocket engine..... There's no manufacturing reason that's logical for the bottle neck. Its not like you are building the engine oon the ground and have to boost it to orbit. Also consider the tonnage of these things. Just how the hell you going to move one of them? Building them at Sol and shipping them all over the inner sphere makes even less since then the other houses not being able tto make them in the first place.

Yes, the rocket engine that hobbyists send up every week is the same as what they used on the X-15, and the same as what was used for the boosters on the space shuttle.

Sarcasm done, the structural engineering that goes in to different scales of rockets is due to their different design jobs and loads.  Heck, just putting the Jump Core under the stress of movement, which is also much lighter than the Standard Core, by the way, requires different engineering challenges than just being able to lift a Mt Rushmore head at a gravity of acceleration.  The basic engine tech is already there, it's everything in between that needs consideration.

[Atarlost]

The thing about large craft engines is that they don't have to scale like mech and ASF engines.  The Mammoth obviously has four by the art.  The Aegis and McKenna have lovely rear shots that plainly show two and three respectively.  There's no in universe reason a small, slow, starter warship couldn't have been built around existing large dropship engines.  Two Behemoth engines (or twice as large a cluster if the Behemoth is already using a clusters) should by Newton get you a 200,000 ton 2/3 warship.  Three should get you a 3/5.  The Fox is a little larger than that, but a satisfactory starter warship could have been designed to the available dropship transit drives. 

[Hellraiser]

Its not like the Fox sat there for 20 years w/o an engine.

They only had the Helm Core for 25 years at that point & didn't start even working on Warships till what, 8 years?, prior to its launching.

In that time they had to work out what the Helm Core had, then had to deal w/ scaling up the shipyards to Warship production.

I'm sure there were other bottlenecks & hurdles along the way.

And its not like they were using CS engines for long.   

By the time they lost Terra the FS had 3 locations going producing 2 different warships, so they had clearly overcome their own issues & were creating engines on their own.

1 snipit of info from 3057 that was probably only relevant for a year or 2, 5 at most, is not this "it was impossible for them" that its made out to be.

They were stuck, they saw a way to speed up the process,  CS said no,  they were working on alternatives, CS finally said, Ok,  so they went with CS & continued to work on the Alternatives to bring mass production on line.

Which is why the Fox is by FAR the most mass produced IS ship come 3067 with something close to 2 dozen of the class floating around out there.

Sure the FWL & DC get credit for massive variety of ships, but the FC was making ships in raw #s designed to transport large #s of dropships to support the Army with large #s of Assault Droppers & Fleet Wings assigned to them.


The only class out there that can compare to the raw combo of (#s + size + quality of design) is the Thera which is so well designed compared to most of the other IS ships as to almost be a crime & yet gets 6-8 of them cranked out in just a few years.

[idea weenie]

So the dropship drives are more inefficent then the Warship drives.   

Dropship drives have to deal with vacuum and different atmosphere types, while Warship drives only have to deal with vacuum.

The additional equipment to remain efficient and safe when going from space to atmosphere could easily explain the difference in mass.

Here is a reddit post explaining more about it.  Short version is that the upper stage Merlin engine had a larger engine bell because it was to fly in vacuum.

So if you have an engine that has to work in both environments, you need some sort of containment for the exhaust while in vacuum to keep it at the engine's proper efficiency.  This could be additional magnetic field systems to extend the fusion containment, or additional panels that extend over the exhaust that are physically moved into place.  Since a pure vacuum engine (i.e. Warship) doesn't need the variable-performance modifications, it is lighter for the same thrust.

[Daryk]

Good point Idea Weenie... the thing that comes to mind though, is why not just accept the inefficiency to get a WarShip (ANY WarShip) into production?  Perhaps we should start a design forum thread for this, with the parameters being a standard Behemoth engine (13,000 tons) and everything else normal (meaning the designs would be either 100,000 tons with 2/3, or 200,000 tons with 1/2 thrust).  The latter would  be particularly scary in the 3040s...

[Wrangler]

Fluff wise, they had better things to pour resources that were spread out between vast galactic partners who had the parts to supply production of a Warship's engines.  Look at the League when they tried build those 3050 destroyers, the Impavido. It took alot effort to pull in enough to just build interplanetary drives for the League.

Allegedly it was the big engines and not the compact kf drives themselves that were the issue when the TRO: 3057 explain what was going on.

Fluff wise it just plain hard get resources gathered, thus the expense went through the roof.  Which is all fluff reason, the focus of the game is Mech combat, everything secondary.  Warships could trump too much so they were made exceedingly hard to make and afford. 

Which i think sucks.  I like naval combat, i believe the universe is big enough for more than 2 warships per succession house or faction to exist. Which would not cause armies not to march on each other.

[Vition2]

It seems that the real problem appears to be the power distribution systems.  At transit speeds a 100kt civilian dropship's engine only uses 8.83 tons of fuel per burn-day (and only 1.84 using the hyper-efficient military engines), meanwhile a warship uses more than double that at 19.75.  The K-F drive by itself may force significantly heavier power systems, and other items such as capital-scale weapons and/or electronics systems (targeting, sensors, etc.) may not be "warship-level" if left to dropship power levels. 

Could an odd merge between a warship and dropship have existed?  Probably, but some pretty serious drawbacks may have been needed to create a compromise which the house militaries were unwilling to consider (I mean, think about a heavy assault dropship, with half it's weight used towards a K-F drive, but unable to charge the K-F drive via the internal power system, and weapons stuck to standard sized).

[Hellraiser]

Good point Idea Weenie... the thing that comes to mind though, is why not just accept the inefficiency to get a WarShip (ANY WarShip) into production?  Perhaps we should start a design forum thread for this, with the parameters being a standard Behemoth engine (13,000 tons) and everything else normal (meaning the designs would be either 100,000 tons with 2/3, or 200,000 tons with 1/2 thrust).  The latter would  be particularly scary in the 3040s...

What makes you think the KF Core issue had been resolved in the 3040's?

They didn't even start working on the Fox till the Year of Reprieve (3050/3051) after the invasion had started.