## Creating a Breakaway Hull

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snrdg121408
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### Creating a Breakaway Hull

Hello all,

Breakaway hulls have popped up recently in two topics which has resulted in my not being sure of how the whole thing works.

I am using a PDF copy of HG 2e I downloaded on 09/01/2016.

Per HG 2e PDF page 12: "...This whole process consumes 2% of the combined hull tonnage for extra bulkheads and connections needed, and costs an additional MCr2 per ton consumed...."

1. The HG 2e example on page for a breakaway hull is based on a 1,000 ton hull that has a breakaway as a separate 400 ton vessel.

The extra bulkheads and connections tonnage requirement is 2% of the combined hull 1,000 ton hull which comes in at 20 tons and adds MCr40 to the basic hull cost of 1,000 x 50,000 = 50,000,000 for a total hull cost of MCr90. The 20 tons of extra bulkheads and connectors leaves 980 ton for the other components to be installed.

In the example the 400 ton section 20 ton MD has a Thrust of 5 and 600 ton section 66 ton MD has a Thrust of 9 installed. The combined 1,000 ton hull has an 86 ton MD which the example shows as having a Thrust of 8. Dividing the 86 ton MD by 1,000 results in a percentage of 8.6%. Looking at Step 2 Install Drives, page 14, Thrust Potential Table the 1,00 ton hull's 8.6% of hull tonnage falls between the MD Rating of 8 and 9. The rounding convention IIRC in MgT is to round down unless specified on how to round which means that the 1,000 ton hull's 86 ton MD has a Thrust of 8.

2. The 400 ton Fessor Cargo-Class Multipurpose Ship published by Jon Brazer Enterprises is designated as using a breakaway hull.

Following the HG 2e process the combined 400 ton hull has a cost of 400 x 50,000 = Cr20,000,000. The tonnage and cost of the extra bulkheads and connectors is 400 x 2% = 8 tons at a cost of 8 x Cr2,000,000 = Cr16,000,000.

The Fessor's record sheet has the Breakaway Hull as 196 tons with the extra bulkheads and connectors requiring 4 tons at a cost of Cr8,000,000. The 196 tons represents the total tonnage of the four 46-ton pods.

To determine hull tonnage used for the extra bulkheads and connectors 4 tons I divided 4 by 2% which equals 200 tons.

The Fessor designer appears to have split the 400 ton hull into two 200 ton sections. One of the 200 ton sections was further divided into four smaller sections. The 200 ton section that was split into four sections appears to have been used to determine the tonnage and cost of extra bulkheads and connectors.

What am I missing in the directions in how to create a breakaway hull?
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

Looks like the Fesaor design only took the beakaway tonnage intro account and not the total tonnage. they are 4 tons short on connectors.Good catch.

So each sub ship should have 1 ton of connectors on it. Reduce cargo by 1 ton and you would be okay, adding in the extra cash.

8 million. Docking clamp design would be cheaper. When I finish work tonight I will post a rough design.
AnotherDilbert
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### Re: Creating a Breakaway Hull

snrdg121408 wrote: 1. The HG 2e example on page for a breakaway hull is based on a 1,000 ton hull that has a breakaway as a separate 400 ton vessel.
Yes, this example is correct.

snrdg121408 wrote: 2. The 400 ton Fessor Cargo-Class Multipurpose Ship published by Jon Brazer Enterprises is designated as using a breakaway hull.
The Fessor appears to be somewhat non-standard. I have not seen the detailed design.

When I design breakaway ships, I tend to start with the whole complete ship, and then subdivide the components to the included breakaway sections.
snrdg121408
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### Re: Creating a Breakaway Hull

Hello PsiTraveller,
PsiTraveller wrote:
Tue Jan 14, 2020 5:52 am
Looks like the Fesaor design only took the beakaway tonnage intro account and not the total tonnage. they are 4 tons short on connectors.Good catch.
Yes, the Fessor design does appear to have determined the extra bulkheads and connectors for the four pods. The apparent 4 ton shortage, in my opinion, should be deducted from the 200-ton core hull.
So each sub ship should have 1 ton of connectors on it. Reduce cargo by 1 ton and you would be okay, adding in the extra cash.
Each pod, or sub-ship, is listed as being 49-tons. If the 4 tons of extra bulkheads is divided by 2% the total tonnage is 200-tons. Dividing the 200-tons by 4 results in each pod being 50-tons versus the listed 49-tons.
8 million. Docking clamp design would be cheaper. When I finish work tonight I will post a rough design.
When the breakaway hulls are combined per the write-up the drives and power plants of all the sections combine together when they are together. Each pod's MD is 0.5 tons for a total of 2-tons. The Fessor's core hull has an 8-ton MD-2 adding the combined to 2-tons pushes the combined MD tonnage to 10 tons. Dividing 10 by 400 returns a percentage of 2.5 which based on the Thrust Potential Table is a Thrust of 2 with or without the four pods.

I think AnotherDilbert, in a different topic, indicated that a hull using docking clamps does not have the ability to combine the drives and power plants outputs in the same way as a breakaway hull when all the sections are combined into one hull.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

Hello again AnotherDilbert
AnotherDilbert wrote:
Tue Jan 14, 2020 9:53 am
snrdg121408 wrote: 1. The HG 2e example on page for a breakaway hull is based on a 1,000 ton hull that has a breakaway as a separate 400 ton vessel.
Yes, this example is correct.
Thank you for another confirmation I understood and followed the instructions correctly.
snrdg121408 wrote: 2. The 400 ton Fessor Cargo-Class Multipurpose Ship published by Jon Brazer Enterprises is designated as using a breakaway hull.
The Fessor appears to be somewhat non-standard. I have not seen the detailed design.
Anything is possible.
When I design breakaway ships, I tend to start with the whole complete ship, and then subdivide the components to the included breakaway sections.
I believe that the directions for the breakaway hull indicates that you take whole ship's tonnage to determine the tonnage and cost for the extra bulkheads and connectors before splitting the hull into sections. After that you build separate hulls following the checklist.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

I've played around with a Breakaway design with a Dispersed configuration and I have a few questions for you snrdg.

How cost efficient are you looking to have the design?

Do you want the ship to be a Breakaway hull or use docking clamps? or a mixture of both? (There are advantages to both designs, but money can be a factor.

Here are the design issues I have come up with so far.

Using the 400 tons as a base, and the 196 tons as sub units I get 8 tons of connector modules for 16 million. Using the Dispersed configuration only for the 204 tons of "Main Hull" saves you 5 million Credits. I did not use the Dispersed configuration for the sub units because you want them to be able to skim or land on a planet. Page 143 of the Core book shows why streamlining is a good idea for this.

The sub units lose 1 ton of space from each design, basically a ton of cargo space is lost for each design to make space for the Breakaway connectors. I did not make the sub unit ships Dispersed. You have to decide if you want to pay extra to streamline the ships or just have them partially streamlined under standard construction.

At the end of it you have a core dispersed ship and then standard or streamlined sub units connected to the Dispersed Core. The sub unit ships move cargo, land, skim or dock to a Highport and the Core stays out in space. That's the concept I get for this right now.

Condottiere
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### Re: Creating a Breakaway Hull

In good design, form tends to follow function.

Since I'm not familiar with the Fessor class, I'm going to speculate that the subpods are forty nine tonnes because someone might have been calculating the two percent breakaway and somehow forgot to account for it by the end of the design sequence, otherwise the most logical tonnage is fifty, as that would be the cap on intermediate smallcraft, with monocockpits.
snrdg121408
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### Re: Creating a Breakaway Hull

Hello PsiTraveller,

Web gremlins have apparently been at work since I know I replied already. Here is try two.
PsiTraveller wrote:
Tue Jan 14, 2020 10:57 pm
I've played around with a Breakaway design with a Dispersed configuration and I have a few questions for you snrdg.

How cost efficient are you looking to have the design?
At the moment I'm trying to build a spreadsheet to verify the Fessor's numbers as a breakaway hull. I'm just starting determining the required fuel tankage. So far the only difference I've stumbled across is the breakaway hull.

At this time I would have to say which is cheaper to build and then maintain over time.
Do you want the ship to be a Breakaway hull or use docking clamps? or a mixture of both? (There are advantages to both designs, but money can be a factor.
The Fessor is, per the write-up, using a breakaway option. How about two designs one using only docking clamps and the other a mixture.
Here are the design issues I have come up with so far.

Using the 400 tons as a base, and the 196 tons as sub units I get 8 tons of connector modules for 16 million. Using the Dispersed configuration only for the 204 tons of "Main Hull" saves you 5 million Credits. I did not use the Dispersed configuration for the sub units because you want them to be able to skim or land on a planet. Page 143 of the Core book shows why streamlining is a good idea for this.

The sub units lose 1 ton of space from each design, basically a ton of cargo space is lost for each design to make space for the Breakaway connectors. I did not make the sub unit ships Dispersed. You have to decide if you want to pay extra to streamline the ships or just have them partially streamlined under standard construction.

At the end of it you have a core dispersed ship and then standard or streamlined sub units connected to the Dispersed Core. The sub unit ships move cargo, land, skim or dock to a Highport and the Core stays out in space. That's the concept I get for this right now.

The Fessor write up as far as I can tell has pod detaching and using the onboard computer with virtual crew to deliver itself to the destinations so the core hull does not really have to leave the, with the early jump option, 90D Limit. Since the Fessor has an autonomous fuel collection pod variant partial streamlining would be adequate.

The overview looks good thank you for your time and effort.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

Hello Condottiere,

The web gremlins where very busy since I replied right after I finished with my comments to PsiTraveller and here is my second go with this post.
Condottiere wrote:
Wed Jan 15, 2020 3:11 pm
In good design, form tends to follow function.

Since I'm not familiar with the Fessor class, I'm going to speculate that the subpods are forty nine tonnes because someone might have been calculating the two percent breakaway and somehow forgot to account for it by the end of the design sequence, otherwise the most logical tonnage is fifty, as that would be the cap on intermediate smallcraft, with monocockpits.
The Fessor's record sheet in the Hull block lists the following:

400 tons, 160 Hull Points Tons column = 400 and Cost column with a (Cr) = 20,000,000
Breakaway Hull (196 tons) Tons column = 4 and Cost column with a (Cr) = 8,000,000

None of the pods record sheets mentions the breakaway hull.

The pods do not have a bridge or cockpit installed for a live body to occupy they have a computer running the virtual crew software.

I agree that the most logical pod tonnage is probably 50 tons as it now stands each pod has 19 hull point with the total for the 196 tons being 78.4 rounding down by the MgT rounding convention and the 204 ton hull having 81.6 hull points rounding down to 81 tons missing the 400 ton hull points of 160 by one point.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

I am messing around with the Fessor ship and I think they made a few more errors in math:
1: Armor for the ship may be off by a lot. The Core unit page 4 has 3 points of Crystal Iron Armour for 15 tons. This costs 3 Million. 15 tons of armour would protect 400 tons of ship, but the rest of the sub units also have armour tonnages and costs listed, which means they used the armour calculations twice and are paying for twice as much armour as needed.

The Core unit of 204 tons should have 7.65 tons of armour and the sub units should have 7.5 tons of armour divided between them, which they do, so the Core ship saves some tonnage and cash

2: Turrets on the main ship shows 2 Pop up triple turrets. Weapons in each turret are 2 missile racks and a Sandcaster.
A Pop up Triple Turret is 2 tons ( Highguard pg 24) and 2 MCr each; 1 MCr for the triple Turret and +1 MCr for the Pop up capability) Missile racks are 0.75 each, so 1.5 for a turret, and .25 for a Sandcaster. If my math is right that should be 2 tons, and 3.75 MCr per turret. They show 1 ton per turret and 5.5 MCr.

3: Also when I add the costs up in the Cost column on page 4 of the pdf I get a cost of ship of 109.595 MCr, not the 104.095 Cost shown on the bottom of the page. And this number ignores the costs savings of cheaper turrets and armour from my first 2 points.

Anyone else agree with this? Or am I making a math error on my side?
PsiTraveller
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### Re: Creating a Breakaway Hull

My Dispersed version of a breakaway ship

200 Ton Core Unit Dispersed Hull 72 Hull Points Cost 5 MCr (half price!)
Breakaway Hull Connectors for 400 tons of ship: 4 tons 8 MCr (8 tons total, 2% on this 200 ton piece of hull, and 2% on every other piece)
3 Points Armour taking up 15 tons of space (double tonnage for a Dispersed Hull) But costing only 0.75 MCr (5% of 5 MCr Hull Cost * 3 Points, so money saved I think)
15 Tons Early Jump Drive 24.75 MCr
8 Tons M Drive (Thrust 2 at 400 Tons) 16 MCr
Power Plant 17 Tons 10.625 MCr
42 Tons Fuel
Bridge 20 Tons (To Control a 400 Ton Ship) 2 MCr
Civilian Sensors 3 MCr
2 Pop Up Triple Turrets with 4 missile racks and 2 Sandcasters 7.5 MCr
8 Staterooms 32 Tons 4 MCr
8 Tons Common Area for 0.8 MCr
Software at 6.1 MCr just like the Fessor
34 Tons Cargo.

Total Cost 88.845 MCr
PsiTraveller
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### Re: Creating a Breakaway Hull

Sub Unit of Breakaway ship: Cargo Module

The only changes to the Sub Units are to Increase the Tonnage to 50 Tons of Ship and add in 1 Ton of Breakaway Hull Connector for 2 Million

If you took all 4 Units as Cargo you could move 212 tons of cargo, at a cost of 212 Million or so credits.

A Subsidized Merchant can move 199 tons of cargo and only costs 81 Mcr. But it cannot be in 5 places at once getting cargo, nor can it change out for different jobs. So it depends on what you want to do.
snrdg121408
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### Re: Creating a Breakaway Hull

Morning as in 5:44 AM Pacific Standard Time PsiTraveller,

I noticed this post as I was shutting down my computer for the night so I apologized answering this one before the other two pasted later.
PsiTraveller wrote:
Mon Jan 20, 2020 3:19 am
I am messing around with the Fessor ship and I think they made a few more errors in math:
1: Armor for the ship may be off by a lot. The Core unit page 4 has 3 points of Crystal Iron Armour for 15 tons. This costs 3 Million. 15 tons of armour would protect 400 tons of ship, but the rest of the sub units also have armour tonnages and costs listed, which means they used the armour calculations twice and are paying for twice as much armour as needed.

The Core unit of 204 tons should have 7.65 tons of armour and the sub units should have 7.5 tons of armour divided between them, which they do, so the Core ship saves some tonnage and cash

2: Turrets on the main ship shows 2 Pop up triple turrets. Weapons in each turret are 2 missile racks and a Sandcaster.
A Pop up Triple Turret is 2 tons ( Highguard pg 24) and 2 MCr each; 1 MCr for the triple Turret and +1 MCr for the Pop up capability) Missile racks are 0.75 each, so 1.5 for a turret, and .25 for a Sandcaster. If my math is right that should be 2 tons, and 3.75 MCr per turret. They show 1 ton per turret and 5.5 MCr.

3: Also when I add the costs up in the Cost column on page 4 of the pdf I get a cost of ship of 109.595 MCr, not the 104.095 Cost shown on the bottom of the page. And this number ignores the costs savings of cheaper turrets and armour from my first 2 points.

Anyone else agree with this? Or am I making a math error on my side?
I believe I mentioned that I'm using the Fessor as a sample during the building a spreadsheet and my conclusion is that the author/designer appears to have completed a 400 ton star ship and then added the breakaway hull option.

Using the total 400 ton hull adding 3 points of crystaliron armor for protection requires 3 x 1.25 x 400 = 0.0375 x 400 = 15 tons and 3 x 0.05 x 20,000,000 = 0.15 x 20,000,000 = 3,000,000

The maneuver driver, jump drive, and power plant appear to have been designed based on a 400 ton hull. I have just started allocating fuel tonnage.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

Hello again PsiTraveller,
PsiTraveller wrote:
Mon Jan 20, 2020 3:42 am
My Dispersed version of a breakaway ship

200 Ton Core Unit Dispersed Hull 72 Hull Points Cost 5 MCr (half price!)
Breakaway Hull Connectors for 400 tons of ship: 4 tons 8 MCr (8 tons total, 2% on this 200 ton piece of hull, and 2% on every other piece)
3 Points Armour taking up 15 tons of space (double tonnage for a Dispersed Hull) But costing only 0.75 MCr (5% of 5 MCr Hull Cost * 3 Points, so money saved I think)
15 Tons Early Jump Drive 24.75 MCr
8 Tons M Drive (Thrust 2 at 400 Tons) 16 MCr
Power Plant 17 Tons 10.625 MCr
42 Tons Fuel
Bridge 20 Tons (To Control a 400 Ton Ship) 2 MCr
Civilian Sensors 3 MCr
2 Pop Up Triple Turrets with 4 missile racks and 2 Sandcasters 7.5 MCr
8 Staterooms 32 Tons 4 MCr
8 Tons Common Area for 0.8 MCr
Software at 6.1 MCr just like the Fessor
34 Tons Cargo.

Total Cost 88.845 MCr
Nice work, whenever I get my spreadsheet done I'll see if I can recreate this ship.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

Howdy again PsiTraveller,
PsiTraveller wrote:
Mon Jan 20, 2020 3:58 am
Sub Unit of Breakaway ship: Cargo Module

The only changes to the Sub Units are to Increase the Tonnage to 50 Tons of Ship and add in 1 Ton of Breakaway Hull Connector for 2 Million

If you took all 4 Units as Cargo you could move 212 tons of cargo, at a cost of 212 Million or so credits.

A Subsidized Merchant can move 199 tons of cargo and only costs 81 Mcr. But it cannot be in 5 places at once getting cargo, nor can it change out for different jobs. So it depends on what you want to do.
Taking a quick look one Type II docking clamp is capable of attaching objects from 31-99 tons. Using two Type II docking clamps per side for a total of four requires a total of 20 tons of hull at a cost of MCr4. The use of four docking clamps instead of a breakaway hull appears to add more flexibility in the size of the pods being carried.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

I wouldn't use type two docking clamps, rather a series of type ones.
PsiTraveller
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### Re: Creating a Breakaway Hull

4 Docking Clamps for 4 MCr and 20 tons. This means the core unit loses 20 tons of cargo. 20 tons is 5% of your total 400 ton design. The Breakaway hull connectors only take up 8 tons, for 16 Million credits. So there is a cost saving. But you lose 12 tons of cargo in exchange.

Carrying 4 ships is possible, even 4 ships like the sub units. But the Docking Clamp carried ships would not be hooked up to allow their fuel, power and M-Drives to contribute to the ship like Breakaway units would. Your fuel module ship would have to transfer fuel from itself to the ship in a separate action, not automatically through the breakaway connections.

I like the idea of a Core unit Jump section with Docking Clamps to carry a 99 ton cargo module. I think this can offer a ship a lot of flexibility and profitability. The part that sucks is that the 99 ton limit means you cannot jump a 100 ton small ship from system to system as a service, you have to the 10 ton clamp to move 100-300 tons at a time. Jump Nets can be used to shift ships though, so that's an option.

You seem to be looking at Breakaway Hulls or Docking Clamps to give flexibility to a ship design. What sort of job is the ship needing to do? Is there a time when you think Docking Clamps would be better than a Breakaway ship?

A series 1 Clamp can only hold 30 tons of ship. The Fessor units are 49 tons, or 50 if you redo them and include the 1 ton of connector hull the design left out.
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### Re: Creating a Breakaway Hull

Hello Condottiere,
Condottiere wrote:
Mon Jan 20, 2020 2:38 pm
I wouldn't use type two docking clamps, rather a series of type ones.
Yes, you could use multiple Type I docking clamps with each clamp requiring 1 ton of space at cost of MCr0.5 per clamp. To carry one 49-ton pod requires a minimum of two Type I clamps which requires 2 ton of space at a cost of MCr1 giving one docking station the capability of attaching an object up to 60 tons. With four docking stations eight Type 1 docking clamps requires 8 tons of space at MCr4. Using two docking stations the maximum tonnage that could be attached is one 120 ton object.

My selection of Type II docking clamps would allow two docking stations to attach one 198 ton object. To be honest I believe that a Type II docking clamp is capable of attaching an object that is between 1 and 30 tons which seems not to be the case.
snrdg121408 (aka Tom R)
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### Re: Creating a Breakaway Hull

I do not think you can use two smaller clamps to carry a larger ship. My reading of the Docking clamp is that it is one clamp, one ship. So a 50 ton ship would need a Type 2 Docking clamp, not two Type 1's

Am I wrong in this? pg 43 of Highguard

The size of a docking clamp dictates the tonnage of the
ship it may attach as shown in the Docking Clamp table.

I don't see anything that says you can use three 1 ton clamps to hold a 90 ton ship, instead of a single 5 ton clamp to hold a 90 ton ship.
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### Re: Creating a Breakaway Hull

Unless fifty tonne clamps can carry an infinite number of tonnes, I think this can be scaled.

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