Thickness of hull armour

F33D

Mongoose
I was curious as to the thickness of armour for a ship. So, I used a sphere of 100 Dtons (1400 M3).

5% (5 dtons) of armour comes to ~11.8 cm (4.7 inches) thickness.
 
Yes

However to highlight something that crops up from time to time look at the thickness for larger and smaller spheres.


Dtons......length.....Volume of Arm...... Surface Area m2.... Arm Thickness (rough not exact)
10............7..........7m3.....................154......................4.5cm
50...........11......... 35m3....................380.....................9cm
100.........14..........70m3....................615.....................11cm
500........ 24.......... 350m3..................1809....................19.5cm
1,000......50..........700m3................. 2827.................... 25cm
10,000....64..........7,000m3...............12,867................. 54.5cm
50,000....112........ 35,000m3............. 39,408................. 89cm
100,000.. 140.........70,000m3............ 61,575..................1.14m
500,000.. 240........ 350,000m3........... 180,955................1.94m
1,000,000..300......700,000m3........... 282,743................2.47m

For the same % of volume a 10Dton fighter has half the armour thickness of your 100Dton ship and the Happy Beach Ball of Death at 500,000Dtons has 19 times as much armour thickness and yet it all stops exactly the same damage :roll:
 
TNE had a more consistent system of determining armor volume. The the idea was you actually selected your armor thickness in cm, then multiplied by a "Toughness" value for material selected to determine its Armor Value. Spacecraft had a minimum Armor Value necessary of 10xG's of Maneuver Drive (to fend off micro-meteors) . So a 1G craft needed a minimum of 10. The Toughness Values were as follows.

2 Hard Steel TL5
3 Titanium Alloy TL6
4 Light Composite TL7
6 Composite Laminate TL8
8 Crystaliron TL10
14 Superdense TL12
28 Bonded Superdense TL14
40 Coherent Superdense TL17
So there depending on material selected your hull thickness ranged from 5cm for steel down to .25cm for coherent superdense. That system however also was more complicated because it dealt with mass for your components and used thrust and reaction drives as well. However, the armor "Toughness" values were somewhat consistent between the TNE and the previous versions of Traveller
 
Armor Ratings can be found in the new Vehicles Handbook. But there they have changed and not exactly the same as those in starships.
Vehicles
1 Wood
2 Iron
3 Steel

4 Crystaliron
5 Superdense
6 Bonded Superdense
7 Coherent Superdense

Starships
2 Titanium Steel
4 Crystaliron
6 Bonded Superdense
 
Nathan Brazil said:
Armor Ratings can be found in the new Vehicles Handbook. But there they have changed and not exactly the same as those in starships.
Vehicles
1 Wood
2 Iron
3 Steel

4 Crystaliron
5 Superdense
6 Bonded Superdense
7 Coherent Superdense

Starships
2 Titanium Steel
4 Crystaliron
6 Bonded Superdense

Doesn't change the fact that a 100Dton ship with 5% of its volume as bonded superdense armour gets 6 points of armour which is 11CM thick and a 500,000Dton ship with 5% of its volume as bonded superdense armour nearly 2 meters thick gets, erm, 6 points of armour.

TNE was a more complex system and of course FFS but it did make a bit more sense than the Happy Beach ball of Death with armour 5 or 6 meters thick getting armour 15 which will stop most turret Pbeams where a scout with armour 25cm thick also gets armour 15 which stops most turret Pbeam hits.

Personaly I would have thought if you go to the time and cost of putting 5 meters of armour on something it would stop most bay weapon fire. But then I use capital bays and have heavily armoured warships with 20-48 armour, player level ships can do nothing more than leave burn marks on proper ships of the line which is how it should be.
 
Captain Jonah said:
Yes However to highlight something that crops up from time to time look at the thickness for larger and smaller spheres.

. . .

For the same % of volume a 10Dton fighter has half the armour thickness of your 100Dton ship and the Happy Beach Ball of Death at 500,000Dtons has 19 times as much armour thickness and yet it all stops exactly the same damage :roll:

Yes, I realized this shortly after I got the MRB. I've created a quick and dirty rule that breaks armour rating into 3 hull categories. Small craft, Medium (MRB hull sizes) & Capital (HG hull sizes).

Create hull with armour and multiply armour rating by .5; 1.0 & 2.0 respectively. If I was actually going to run a dedicated Capital ship game, I'd get more granular at that level.
 
Captain Jonah said:
For the same % of volume a 10Dton fighter has half the armour thickness of your 100Dton ship and the Happy Beach Ball of Death at 500,000Dtons has 19 times as much armour thickness and yet it all stops exactly the same damage :roll:

Except that 10 Dton fighter actually needs twice as much volume of armour for the same armour protection as larger ships...
 
AndrewW said:
Captain Jonah said:
However to highlight something that crops up from time to time look at the thickness for larger and smaller spheres.

For the same % of volume a 10Dton fighter has half the armour thickness of your 100Dton ship and the Happy Beach Ball of Death at 500,000Dtons has 19 times as much armour thickness and yet it all stops exactly the same damage :roll:

Except that 10 Dton fighter actually needs twice as much volume of armour for the same armour protection as larger ships...

Next you'll realize that while your calculations work for spheres there are many other hull shapes to consider and they are all less efficient than a sphere, spreading your armour even thinner for exactly the same protection...

...what you're failing to realize though is:

1: That armour is not just a surface skin feature. Obviously, taking the rules as written it is something else. It probably includes extensive internal bracing, bulkheads, compartmentalization, and other features. Such that the surface skin is probably very much the same thickness for both that 10ton fighter and the 500,000ton dreadnaught. The difference being the dreadnaught has a huge percentage of it's armour beneath the skin in the form of reinforcement to support the size of the thing while the 10ton fighter can probably get away with being a monohull and all of its armour is a thicker skin.

2: It's a game :) The rules are simplified for ease of use and designed to aid in play. If you want to build real spacecraft... ;)

EDIT: I should also add...

3: Armour skin is not a uniform thickness or complete shell. There are of necessity various thinner areas (probably over sensors for example) and areas without armour skin (possibly weapon ports, drive vents, etc.). If one wants to start nitpicking :) Again though, see note 2 above :)
 
AndrewW said:
Except that 10 Dton fighter actually needs twice as much volume of armour for the same armour protection as larger ships...

Which is what my house rule addresses.
 
Far Trader.

For a sphere or a cylinder or any other shape the same effect is seen. The larger ships have much thicker armour.

1. Erm nope :wink:
A ships structure is entirely separate. A 500,000Dton ship with 5% armour has bracing to support its armour but has the same structure as an un armoured one. There is no extra ability to take hits or handle damage. An un armoured ship takes damage the same as an armoured one after the armour is taken off damage.
An armour 6 DN takes an 18 point hit the same way that an Armour 0 DN takes a 12 point hit. While I accept that armour is not just slabs of metal (see below) it should become more effective as it gets thicker and takes up more volume even if a lot of that extra volume is bracing. Saying that the actual armour on a DN is the same thickness as on a scout but needs 25,000Dtons of bracing and frame work to hold it in place is a tiny bit odd. :wink:

2. Yep its a game. Doesn’t stop us from commenting on the fact that it doesn’t make sense and it doesn’t prevent people from house ruling to fix the flaws. :roll:

3. Armour is as thick or as thin on a small ship as it is on a big one. The low armoured areas like hatches, sensors etc are a bigger % of the small ships surface than on a bigger ship. A scout with advanced military sensors has the same sized sensors as that 500,000Dton ship with advanced military sensors, while the DN will need more sensor dishs to give it full sphere coverage it isn't going to need a 1000 times the sensor area. The fighter may have a single shell hull 5cm thick but the fact that it can stop the same 6 points of damage as the meter plus thick layer of heavy armour and bracing on the DN is what is odd. :roll:


Armour modified by size of ship and maximum armour supported by tech level.

Some presumptions here.

Thicker armour begins to include more and more structural bracing and support so it is not solid armour

Most ships are not spheres and therefore have a surface area between 1.1 and 1.5 times larger than listed. (Ave 1.3)

Armour is a complex laminate combining both heavy alloys with heat and energy dissipation layers, the effectiveness of these layers does not scale straight up with size since the ability to dissipate energy has hard limits not based on increases in radiator thickness.

Dtons....Armour Multiplier................Maximum Armour By Tech Lvl
........................................11-..........12..........13.........14..........15...........16

10.......... 0.5.......................5........... 6............6........... 7........... 7............8
50.......... 1......................... 11.......... 12.......... 13.......... 14.......... 15.......... 16
100........ 1......................... 11.......... 12.......... 13.......... 14.......... 15.......... 16
1,000+... 1.25.....................13.......... 15.......... 16.......... 18.......... 19.......... 20
10,000+..1.5...................... 16.......... 18.......... 20.......... 21.......... 23.......... 24
50,000+..1.75.................... 19.......... 20.......... 22.......... 24.......... 26.......... 28
100,000+..2....................... 22.......... 24.......... 26.......... 28.......... 30.......... 32
500,000+..2.5.................... 27.......... 30.......... 31.......... 35.......... 37..........40
1,000,000+..3.................... 33.......... 36.......... 39.......... 42.......... 45.......... 48

This is intended to work alongside the increase in space ship weapon damage by tech blocks

Destroyer sized ships 1000Dtons can quickly become resistant to lower tech turret weapons but can still be damaged by high tech and barbette weapons

Light cruisers 10,000dtons are all but immune to turret weapons but remain vulnerable to all bays and to Meson or Fusion weapons.

Heavy cruisers 50,000Dtons are becoming immune to light bays but can still be hurt by heavy bays though it takes a lot of hits. This is the point where capital bays come into play for use against enemy capital ships.

Battleships at 100,000Dtons + are all but immune to large bays and down, it takes capital bays, capital torpedoes and spinal mounts to hurt them.

DNs at 1,000,000Dtons plus can only be hurt by capital weapons.
 
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