Bringing the Book-2 ships into a Book-5 milieu

[Vile]

It would be an interesting thought experiment to tinker with LBB2 to develop formulas that get "close enough" to the table numbers, and revise the tables based on that.

On a tangent, one thing that RPG gear design sequences don't model very well is simple good design vs. bad design (actually often a simple matter of serendipity rather than designer competence). History is replete with examples of machines which performed better or worse than on paper, and often by accident, not design. Maybe one could add in a "fudge factor" where most of the time things go according to plan, but there is a small chance that a component is smaller, larger, more efficient, less powerful, cheaper, etc.

 

[whartung]

It was always my contention, particularly with T5, that detailed, exhaustive ship/vehicle/equipment design was to be one of the first things done. Much like FF&S.

Once that was done, you establish the "reality" of the "physics" of the universe in play. "Sure, we have steel, but how heavy is it? How strong?"

With that you can adapt combat effects: what happens when a gauss rifle hits a ships hull. WHY does it go "ping" an just bounce off?

Then, given the detailed system, you can boil it down to a faster, modular "book 2" "ACS" system with bigger components, so that folks aren't building 1271 MW reactors or anything else.

The ACS can be looser to fit the table driven format of plug and play, modular components to build ships out of vs the formula and detailed master system.

In the end, they play the same. In the end, the ACS system is a little sloppy, a little less efficient, a "lower resolution" ship so to speak.

But the drives work the same, a MW is a MW, gauss rifles still go "ping" when they hit the side of the ship, etc.

Book 2 was fast a furious, which is why the incompatability with the more detailed system exist. There was no economy, no "science", no foundation for Book 2. It was more "well that sure looks good on a chart", so ship it.

 

[Proneutron]

It was always my contention, particularly with T5, that detailed, exhaustive ship/vehicle/equipment design was to be one of the first things done. Much like FF&S.

Once that was done, you establish the "reality" of the "physics" of the universe in play. "Sure, we have steel, but how heavy is it? How strong?"

The reality of the physics (how strong is the steel). Must be done BEFORE the "detailed, exhaustive ship/vehicle/equipment design" system is completed. Otherwise, there will be built in holes and/or conflicts. If you don't know the properties of your "steel" how do you make a sensical vehicle design system that uses the steel?

 

[Grav_Moped]

The drive potential table is different between 77 edition and 81 edition.

77 the minimum sized drive that would move a 400t ship are the C drives, the B drive is a dashed line showing it will not function in that size of hull.

In 81 edition the B drive will now produce performance 1 in a 400t hull, as will the C drives. Why a bargain basement ship would use anything but the B drive to cut costs is a bit of a mystery.

Not only bargain basement ships. High end ships don't install larger drives than needed either. Even in mil ships one doesn't install more than needed to obtain the designed performance figures. Makes one wonder if the "2nd edition" LBB2 had those leading 1's as a typo in place of the dashes.

The answer to the mystery is that they changed the table but didn't change the standard ships.

I think the first one that seemed out of place (I lined through it on my copy of LBB2'81, but in retrospect I think they meant it) was "J drives in a 2000Td hull". Need to get around to plugging it into Excel to look for irregularities.

I have a sneaking suspicion that there are going to be jumps at drive sizes J and P from having built the table with those letters included, but then removing those columns. And the Z drives, of course.

 

[Proneutron]

The answer to the mystery is that they changed the table but didn't change the standard ships.

Oh. That would explain it.

 

[Grav_Moped]

The answer to the mystery is that they changed the table but didn't change the standard ships.

I think the first one that seemed out of place (I lined through it on my copy of LBB2'81, but in retrospect I think they meant it) was "J drives in a 2000Td hull". Need to get around to plugging it into Excel to look for irregularities.

I have a sneaking suspicion that there are going to be jumps at drive sizes J and P from having built the table with those letters included, but then removing those columns. And the Z drives, of course.

I was mistaken. There isn't a set of irregularities around J and P -- though there is one anomaly for P drives.

If you assume that a drive has Rating Points* equal to twice its ordinal value (that is, A=1, B=2, C=3... H=8, J=9... and so on**), this explains most of the Drive Potential Table. Divide a drive's Ratings Points by the ship's size in 100s of tons and round down to get that drive's rating in a specific hull.

Example: Size A drive in a 200Td hull. Size A=1, multiply by 2 yields 2 Ratings Points. The hull is 200Td, or 2*100. Divide the 2 ratings points by the 2 (hundreds of tons) to get the Drive Rating of 1.

With me so far? If you can come up with a simpler formula, please do. I'm a little tired at this hour; I'll try to simplify it later.

Anyhow, I used this formula to calculate a table similar to the Drive Potential Table, and compared it to the book's Drive Potential Table.
Edit: Added fraction for X at 800Td, added entry for Y at 800Td (they rounded up instead of down).

Variations from calculated rating in the Drive Potential Table:

            Calc’d  Table’s   
Drive  Hull Rating  Rating  
   J   2000   0.84    1

   W   1000   4.2     5
       5000   0.84    1

   X    800   5.5     6
       1000   4.4     6
       2000   2.2     3
       3000   1.47    2
       5000   0.88    1

   Y    800   5.75    6
       2000   2.3     4
       3000   1.53    2
       4000   1.15    2
       5000   0.92    1

   Z   2000   2.4     6
       3000   1.6     4
       4000   1.2     3
       5000   0.96    2

Surprisingly, there was only one anomaly before the TL-15 drives (W-Z), which was where they started really messing with the numbers. Z in a 2000 ton hull is the largest variation, but all of the TL-15 drives in a 5000Td hull are at least rounded up.

J in 2000Td might just be rounding up, but it's not necessary. K (also a TL-11 drive) provides a rating of 1 there.

The TL-15 drive adjustments might be an effort to shoehorn in higher ratings for larger hulls without having to extend the drive table to drives beyond Z. Still, it makes Size Z drives disproportionately powerful.



* Analogous to the Energy Points of LBB5 power plants
** The jump at 9 and the similar one at 14 are because I and O are omitted to avoid confusion.

 

[mike wightman]

Yup, did the same thing fifteen years ago:

http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=10687

my conclusion (on page 2) was there are inconsistencies with the 800t hull and the W drive, the 1900&2000t hulls and the J drive.

 

[BRover]

Book 2: "Using a 400-ton hull, the subsidized merchant is a trading vessel intended to meet the commercial needs of clusters of worlds. It has jump drive-C, maneuver drive-C, and power plant-C,"

That is the Type R drives, not the type R engineering section.

 

[Proneutron]

That is the Type R drives, not the type R engineering section.

No, they are Type C drives

 

[BRover]

No, they are Type C drives

My point was not that the drives are Cs, but that the ship's ENGINEERING SECTION is 50 dTons, which will accommodate J2 2G drives. I know full well that the Type R is J1 and 1G.

 

[Grav_Moped]

Yup, did the same thing fifteen years ago:

http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=10687

my conclusion (on page 2) was there are inconsistencies with the 800t hull and the W drive, the 1900&2000t hulls and the J drive.

Looks pretty thorough, though kind of beat up by formatting issues... LOL

I'm not seeing the issue with W/800, but I realize I overlooked Y/800. Thanks for encouraging me to take another look at my spreadsheet!

 

[Grav_Moped]

My point was not that the drives are Cs, but that the ship's ENGINEERING SECTION is 50 dTons, which will accommodate J2 2G drives. I know full well that the Type R is J1 and 1G.

And it has unnecessarily large drives (C instead of B), something that should have been fixed when they changed the drive table between the '77 and '81 editions.

 

[BRover]

And it [Type R] has unnecessarily large drives (C instead of B), something that should have been fixed when they changed the drive table between the '77 and '81 editions.

Which would be a major price reduction also.

 

[Grav_Moped]

Which would be a major price reduction also.

It's almost as much as the savings from using a standard hull -- MCr22 vs MCr24. And even with the smaller drives wasting 25Td instead of 15Td, it's still cheaper in cost per payload ton per jump to use the standard hull.

As presented in LBB2 (unarmed), the Type R Subsidized Merchant has a cost per payload* ton per jump (two week cycle) of Cr1079. No wonder it's subsidized!

It would be Cr863 per payload ton per jump with Size B drives instead, and might not need a subsidy.

(These figures exclude any payload capacity in the carried Launch.)




*Payload tonnage includes staterooms and low berths.

 

[Grav_Moped]

Let's tackle the Type R in terms of costs, in a few variations. There's the stock LBB2 version, and that with a reasonable weapons loadout. Then there's one with correctly-sized drives, and again but armed as above.
Costs are rounded to the nearest credit.

Type R, per LBB2, unarmed
Payload is 239Td including the 8 staterooms, 9 low berths, and the 2Td reserved for the turrets but not used (assuming small parcels can be stowed there) but excluding any cargo space left over in the Launch.
Its price is MCr101.295 in quantity.
Its cost per payload ton* per jump is Cr1079
Its cost per passenger is 8043**
Its cost per low passenger is Cr739

Type R, per LBB2, with 2 turrets: 1 double missile, one double beam laser
This reduces payload by 8Td for the two gunners' staterooms, while adding their salaries and life support costs.
Payload is 229Td (2 turrets added, and 8Td of passenger staterooms are now gunner staterooms).
Its price increases to MCr105.345 in quantity (weapons also getting the discount).
Its cost per payload ton per jump is Cr1186
Its cost per passenger is Cr8787
Its cost per low passenger is Cr793

Type R, with Size B instead of Size C drives:
Payload is 239Td.
Cost is MCr81.09 in quantity.
Cost per payload ton per jump is Cr863
Cost per passenger is Cr7071
Cost per low passenger is Cr631

Type R, with Size B instead of Size C drives, armed as above:
Payload is 229Td.
Cost is MCr 85.5
Cost per payload ton per jump is Cr960
Cost per passenger is Cr7732
Cost per low passenger is Cr680

Observations:
The Type R, as written, is not profitable at LBB2 cargo rates even if unarmed. Passengers only turn a profit if all staterooms are full and half of them are high passage, at LBB2 rates.

With Size B drives instead of Size C drives, passengers are profitable if staterooms are full.





*payload includes cargo, passenger staterooms, and low berths.
**passenger cost (mid passage, not counting the steward costs) formula is: 4 X (cost of payload ton per jump)+Cr3000 as I calculated in this post.
For this exercise, I am distributing the cost of the single steward across all passengers by adding either 1/8 (for the unarmed version with 8 passengers) or 1/6 (for the armed version with 6 passengers) of the steward's per-jump cost.

This would look like:
8 passengers: ( 1.125 X (4 X (cost of payload ton per jump+3000) ) ) + Cr188
6 passengers: ( 1.167 X (4 X (cost of payload ton per jump+3000) ) ) + Cr251

 

[Straybow]

A Duplex Subsidized Merchant carries a 2-week supply of fuel instead of a 4-week supply. Most subsidized merchants take advantage of the extra space in the 50 dT drive compartment, adding a 10 dT auxiliary fuel tank there so the ship has 4 weeks plant fuel available.

There's a reason why you can't use engineering space for cargo. It's too hot, both thermally and due to neutron radiation. It would be impossible to store LH2 in there.

I do think that the engineering section should simply be the size needed for the drives and power plant, and any common drive/power combination automatically considered a "standard hull" layout for that hull size. I suppose one could be designed with a larger engineering section to allow for an upgrade, but that would be the only reason to have unused engineering space.

 

[Proneutron]

There's a reason why you can't use engineering space for cargo. It's too hot, both thermally and due to neutron radiation. It would be impossible to store LH2 in there.

That means your engineers are dead. :rofl:

 

[Vile]

Based on most published deck plans the engineering sections appear to be shirtsleeve environments, so I assume all dangerous bits are safely tucked away behind shielding.

 

[Grav_Moped]

There's a reason why you can't use engineering space for cargo. It's too hot, both thermally and due to neutron radiation. It would be impossible to store LH2 in there.

I do think that the engineering section should simply be the size needed for the drives and power plant, and any common drive/power combination automatically considered a "standard hull" layout for that hull size. I suppose one could be designed with a larger engineering section to allow for an upgrade, but that would be the only reason to have unused engineering space.

Again, my take on this is that the reason standard hulls are standard is that they're the hull for a commonly-built ship (or perhaps, a once commonly built ship). This implies that their drive bay space should be an exact fit for that commonly-built ship's drives.

I can understand the drive bay being sized for a less-common variant with higher performance (as in the Type R having room for a set of Size D drives for an upgrade to J2, 2G), but the drive bay should then fit those drives exactly. Rules as written, though, they don't.

 

[Vile]

Taking the calculation out of the rulebook and into the Traveller Universe for a moment, I envisage standard hulls as being around for a much longer time than standard drives - in fact, I could see a lot of different companies producing slightly different versions of standard drives for every company that makes standard hulls.

I like to introduce tweaks to ships based on "fluff" like the infamous Type-S air recyclers. So some standard drives might leave more space in the engineering section than others, some might be slightly cheaper, more reliable, whatever. Makes "standard" less boring.

The original Battletech brought this home to me, with the descriptions of mechs and other vehicles replete with quirks and idiosyncracies - which unfortunately had no impact on their game stats. So I went through the whole book and added modifiers based on the descriptions. Sure, that meant some mechs were better than others, but that's how things are in the real world - take any two cars of the same spec and one is certain to be better than the other, sometimes by a considerable margin.

Getting back to standard hulls themselves, I see them as being standard for a slew of reasons - easy to build, versatile volume, cheap material, etc. So, different manufacturers might have their own take on what is otherwise exactly the same standard hull design, from minor dimensional differences to internal bulkheads that are easy to move and thus allow the engineering section to be expanded or shrunk at little cost - think of Norman Foster's HSBC building in Hong Kong, which has whole floors that can be reconfigured.