Armor

All ships in nebulous are covered with a layer of armor. In order to damage components, the attack must first penetrate armor. Armor in neb can be degraded in specific areas by attacks, both penetrating and nonpenetrating. In specific terms: Armor health is stored as a texture mask layered across that takes localized damage only where it is hit. Armor is layered across the hull equally, protecting turrets, radar panels, and thrusters to the same degree as everything else.

Guidelines

Ammo selection for a given targets can be accomplished visually in several steps

• Start by shooting with AP
• If you’re shooting AP, and your shells punch out the back of the target, switch to HE.
• If you’re shooting HE, and you see showers of sparks for ricochets, switch to AP.
• If you’re firing at a small target, fire RPF/Bombshell/Grape until it stops evading, then HE to destroy

Key: X -> Y = “shoot X to damage, then finish with Y”
X or Y = “use X, but Y has situational uses”. Lack of bolding indicates either works
X :-( = “your best option, but alas, it won’t do much”

Ammo Selection Chart

OSP firing at...	100mm	250mm	450mm	600mm
FFL Sprinter	Grape -> HE	Bomb -> HE	HE	Bomb or HESH
FF Raines	HE	Bomb -> HE	HE	Bomb or HESH
DD Keystone	HE or AP	HE	HE	Bomb -> HESH
CL Vauxhall (bow)	AP	AP	HE	Bomb -> HESH
CL Vauxhall (side)	AP	HE	HE	Bomb -> HESH
CVE Levy	HE	Bomb -> HE	HE	Bomb or HESH
CH Axford (bow)	AP	AP	AP	HESH
CH Axford (side)	AP	AP or HE	HE	HESH
BB Solomon (bow)	AP :-(	AP	AP	HESH
BB Solomon (side)	AP :-(	AP	HE	HESH
Any plasma'd target	HE-HC	Bomb -> HE	HE	Bomb or HESH

Ammo Selection Chart

ANS firing at...	120mm	250mm	450mm
Shuttle/Ferryman	RPF-> HE	RPF -> HE	HE
Tug/Draugr	RPF -> HE	RPF -> HE	HE
MN Flathead (angle)	AP	HE	AP
MN Flathead (flat)	AP	AP	HE -> AP
CVL Journeyman	HE	HE	HE
CC Ocello (bow)	AP	AP	AP
CC Ocello (flat)	AP	HE	HE
LN Marauder (bow)	AP or HE	HE or AP	HE or AP
LN Marauder (flat)	HE or AP	HE	HE
CLN Moorline	HE or AP	HE	HE

Mechanics

Armor Damage

Terminology

Nominal armor (NA)

NA is the actual thickness of the armor as listed in the hull description.

Effective armor (EA)

EA is based on the angle of the armor relative to the incoming projectile, increased from NA due to the projectile having to travel through more armor. This is capped at 2.5x nominal armor.

[math]\displaystyle{ \text{EA} = \min\left(\frac{\text{NA}}{\cos\theta}\, ,\, 2.5\times\text{NA}\right) }[/math]

where [math]\displaystyle{ \theta }[/math] is the angle from the normal to the incoming projectile.

Some weapons ignore armor angling, so for these EA simply equals NA.

Remaining armor (RA)

RA is the remaining effective armor, i.e. EA times the current armor health in that location.

[math]\displaystyle{ \text{RA} = \text{current armor health fraction}\times\text{EA} }[/math]

Armor Penetration (AP)

AP is the base penetration stat of the weapon.

If [math]\displaystyle{ \text{AP} \geq \text{RA} }[/math] then the attack penetrates and shreds all the armor at that location. If not, then the armor is damaged according to the process below.

Ricochet

Shells can ricochet off of armor at steep angles with reduced shredding and a visual effect.

If a shell does not have the AP to penetrate, it will ricochet if the angle to the normal is greater than 80 degrees:

[math]\displaystyle{ \text{ricochet if}\quad \theta\geq 80^\circ }[/math]

Damage types that ignore armor angling will not ricochet under any case (as those attacks are always treated as hitting perpendicular to the plate regardless of the actual hit angle).

Damage Formula

For shells that do not ignore armor angling, AP is modified based on the impact angle and amount of armor remaining. Simply, AP is scaled by the fraction of itself over RA.

Putting it all together, the actual shredding applied to the armor is

[math]\displaystyle{ \text{actualDamage} = \text{AP}\times\rho\times\min\left(\frac{\text{AP}}{\text{RA}}\, ,\, 1\right) }[/math]

where [math]\displaystyle{ \rho }[/math] is 0.2 if the shot ricochets or 1 if it does not. Then [math]\displaystyle{ \text{actualDamage} }[/math] is shredded from the armor in a rough circle across the armor shredding radius centered at the point of impact.

For example, a 120mm AP Shell strikes a Solomon at at 30 degree angle from the normal.

• AP = 45 cm.
• EA = NA / cos(30) = 60.0 cm.
• RA = EA (because this Solomon has not taken any hits there)
• Does not ricochet.

Then the actualDamage done is [math]\displaystyle{ \text{actualDamage} = 45 \times \frac{45}{60.0} = 33.7\, \text{cm} }[/math]. So the Solomon would have 18.3 cm of armor remaining in that spot.

• Note that even if armor is reduced to zero, the attack will not penetrate unless the earlier [math]\displaystyle{ \text{AP} \geq \text{RA} }[/math] condition is fulfilled. This generally happens at steeper angles, eg 60cm pen vs 52cm armor at 30 degrees will not penetrate, but will fully strip armor.^{[needs confirmation]}
• Some damage types such as HEI warheads (missiles, rockets, mines), Beams, and Plasma ignore armor angle. This additionally ignores much of the actual damage formula, so 45cm of pen from an attack that ignores angling will always strip 45cm from the armor, regardless of angle or remaining armor thickness

Armor Damage Radius

The damage from the equations above are applied to the mask with a brushsize roughly equal to the armor damage radius. This shredding radius is not listed in game but can be viewed in the specific Munitions & Missiles page.

Overpenetration

Further information: component damage: overpenetration

If a shell is able to penetrate and does not stop inside the hull, it makes another check to penetrate the armor on the other side to exit the hull. The armor penetration is reduced by the distance traveled through the ship's interior density^{[needs confirmation]}. If the second penetration check succeeds, the round overpenetrates and does reduced damage.