GamingDiver / WoWs Legends Ships / ARP Nachi

World of Warships: Legends ship guide

ARP Nachi

Beta

Japan · Tier VI · CA Cruiser · Premium

Improved-AP cruiserIts improved AP fuse citadels cruisers other heavies over-pen; commit to AP and hunt broadsides.

Playstyle

Hold a flank where rotated focus can find island cover within one heal cycle
Avoid: Trading the super-heal advantage in open water

Key characteristics

Long torps (10 km)Wide always-pen zoneSonarDefensive AAFast for the classVisible torps

Arpeggio collaboration variant

Collaboration ships are kept separate from base hulls unless an official collaboration source clearly ties the variant to that page.

On this page

Community stats
Playstyle
How to get ARP Nachi
Builds
Cohort position
Stats and specs
Charts
Background
Armor
Balance history
Exteriors

Community Data

ARP Nachi Community Stats

Across 780+ Standard battles from 63 players, ARP Nachi averages a 63% win rate, 56,800 damage and 1.2 kills per battle, and survives 47% of them.

Community Data

ARP Nachi Community Stats

Log in to GamingDiver and upload your data to see Community Data for ARP Nachi: community win rate, damage, survival, spotting, and your own comparison.

Playstyle

Overview

ARP Nachi is a Tier VI Japanese IJN cruiser with the improved AP fuse: her AP shells arm at 60% of the standard armor threshold, so they citadel cruisers that would over-pen a normal CA round. Lean on AP into broadsides and short-angled cruisers - HE-spamming this hull leaves the cohort's best damage tool on the rack. She also packs the super-heal (1%/s, for 20 s, every 80 s, 3 charges): each Repair Party charge returns dramatically more HP than a standard heal, so her durability comes from sustain alongside the lead trait. Sonar (4.2 km on ships and 3 km on torpedoes, 94 s active, 180 s reload, long uptime) lights up DDs and torpedoes inside its bubble, which lets her contest the cap edge without taking the spotting cycle. Standout traits: top speed in T6 CAs (35 kt, 8th of 44) and heavy AP shells in T6 CAs (5,150, 5th of 43). The trade is torpedo detection in T6 CAs (1.6 km, 29th of 34).

Positioning

Hold a flank where rotated focus can find island cover within one heal cycle. The super-heal (~1%/s, roughly twice a standard heal) makes sustained trades profitable that would not be on a standard cruiser, but only if you finish the trade behind cover; open-water sustain just feeds shells. The helm answers fast (7.2 s) but the circle is wide (780 m): weave to spoil aim rather than committing to turns, because a committed turn gives up more water than the quick rudder saves you.

Potato Avoidance

Trading the super-heal advantage in open water

The kit rewards finishing the trade behind cover so the heal recovers what the salvo took; sustained open-water exposure burns through all 3 charges before the cooldown completes.

Signature Traits

Improved AP fuse (IJN cruiser)

AP arms at 60% of the standard armor threshold (vs 0.9 default). Lets your AP pen broadsiding cruisers that would over-pen a normal CA, citadel hunts the cohort can't pull off, shared by 7/44 T6 CAs.

Fast for the class ↗

35 kt, top decile of T6 CAs. Lets you rotate flanks or escape disengagements.

ELITE MAIN BATTERY ↗

Heavy AP shells · 5150 damage
Big-caliber AP overmatch · 14.1 mm

Best-in-class stealth ↗

11 km surface detect, top quartile of T6 CAs. Stays dark longer.

ELITE TORPEDOES ↗

Big torpedo salvo · 6 tubes
Module-wrecking torpedoes · 1300 torpedo

Visible torps ↗

1.6 km torpedo detect, bottom decile of the 34 T6 CAs with torpedoes. Spotted early, so targets get a long look and room to turn out.

Acquisition

How to get ARP Nachi

ARP Nachi is a Premium ship and not available to unlock in the Tech Tree. Acquisition path: Containers. Container chances are shown as the listed odds of receiving this exact ship, dividing grouped ship-pool odds across the resolved ships and including nested container paths when a crate can drop another crate.

ContainersAppears in official container odds below; availability depends on the container being sold or awarded.

While you save up, check active promo codes for free doubloons, camouflages, and other rewards.

Best listed chance for this ship

Arpeggio II crate 2.5% Arpeggio II Premium Ship Collaboration · Arpeggio II crate · 1 of 2 ships

Show direct source rows

Arpeggio II crate 2.5% · Arpeggio II Premium Ship

Want the full picture? Each container page charts the odds as you open more crates - including ~~pity~~ guaranteed-reward timers and, for GD Supporters, pack math personalized to your port.

Builds

Pair with a commander whose unique skill complements her main armament; check the build tool for current recommendations.

Open in Build Tool →

Have a build you swear by? Open it in the Build Tool and hit Save build to share it here, or browse the Ship Builds guide for proven loadouts across the fleet.

Cohort position

Hide ▾

Where ARP Nachi sits among Tier VI CAs (43 ships). Notable standouts are shown first; the rest of the cohort-ranked stats are in the expand below. Acquisition variants (Black Friday, Founders Edition) are counted once with their base ship, not as separate peers.

LongestAP fuse timer0.033 s (1 of 21 tied) Top 10%AP auto-bounce angle70° (4/43) Top 25%Max speed35 kt (8/44) Top 25%Concealment10.98 km (6/44) Top 25%Rudder shift7.2 s (7/44) Top 25%AP DPM292,297 (8/43) Top 25%Main dispersion133.1 m (11/44) Top 25%Secondary HE alpha2,100 (5/39) Top 25%Secondary fire chance8% (9/39) Top 25%Secondary HE pen21 mm (9/39) Top 25%AP ricochet start55° (7/43) Top 25%Engine power130,000 hp (7/44) Top 25%Power / turn radius166.7 hp/m (9/44) Top 25%Torpedo damage≈15,933 (9/34) Top 25%Repair charges3 (3/14) Bottom 25%Turning circle780 m (37/44) Bottom 25%Main battery range14.5 km (37/44) Bottom 25%Secondary DPM (per side)66,566 (33/39) Bottom 25%Displacement15,807 t (35/44) Bottom 25%Torpedo reaction time9.6 s (30/34)

See 33 mid-pack stats

Not standouts for ARP Nachi -- here's where she sits on every other ranked stat in the cohort. Stats tagged NORM are tied across more than half the cohort, so the value is the cohort default rather than a standout.

Hit points36,200 HP(13/44) Smoke fire bloom6.06 km(21/44) Air detection7.19 km(25/44) Main battery caliber203 mm(14/44) Main battery reload10.5 s(22/44) Sigma2(24/44) HE shell damage2,500(21/37) HE fire chance10%(27/37) Fires per minute5.68(28/37) HE DPM141,892(17/37) AP velocity840 m/s(29/43) HE velocity840 m/s(25/37) Time to 90% speed25.3 s(32/44) Acceleration (0-12 kt)8.7 s(21/44) AP arming threshold34 mm(30/43) Power-to-weight8.22 hp/t(17/44) AP pen at 10 km203 mm(17/43) Effective HE DPM (incl. fire)184,368(20/37) AA DPS267(24/44) AA range5 km(15/44) AA threat953(23/44) Flak damage per salvo (expected)756(27/43) Torpedo range9.99 km(11/34) Torpedo speed62 kt(15/34) Torpedo reload82 s(15/34) Repair heal rate1 %/s(6/14) Max armor102 mm(31/44) Citadel belt102 mm(27/44) Bow armor16 mm(25/44) Stern armor16 mm(25/44) NormSecondary dispersion bracket57(38 of 39 tied at this value) NormTurn speed retained81%(39 of 44 tied at this value) NormSecondary range4.5 km(26 of 39 tied at this value)

Peers in this cohort

Compare Tier VI Cruisers

Show all 43 peers

Stats & specs

Customize in the Build Tool →

Survivability

Hit Points36,200

Displacement15,807 t

Hull dimensions

Length x beam at the waterline, plus draft. Length matters when dodging torpedoes; beam and draft shape how hard the ship is to hit.

202.8 x 20.4 m (ship-model figure)

Armor range6–102 mm

Plate armor thicknesses6, 13, 16, 19, 21, 25, 30, 32, 35, 38, 40, 50, 57, 63, 76, 89, 102 mm

Armor material/layer entries59

Fire resistance

top hull: 1 − 0.7003 fire coefficient = 30%. Lowers how often hits set you on fire. It does not reduce the damage a burning fire does per second; fires burn at the full rate on every ship.

30%

Fire duration30 s

Fire damage

One unattended fire: 0.003 of max HP per second (0.3%) × 30 s = 0.09 of the pool; 0.09 × 36,200 HP = 3,258 HP on this ship. 4 fire points can burn at once.

0.3% of HP per second

Flood duration40 s

Flood damage

One unattended flood: 0.0025 of max HP per second (0.25%) × 40 s = 0.1 of the pool; 0.1 × 36,200 HP = 3,620 HP on this ship.

0.25% of HP per second

Torp Reduction

1 − 0.29 hull torpedo-damage coefficient / 0.333 unprotected baseline = 13%. Reduces torpedo hit damage. It does not affect flooding: floods start as often and tick at the full rate.

13%

Magazine HP

Per-turret powder-magazine HP, a separate pool from the ship's. Penetrating hits wear it down and the turret is likelier to be knocked out as it falls, so a larger pool keeps the guns firing through punishment that silences a peer's.

19,600

Steering gear HP

Durability of the steering gears. As this pool drops, hits are likelier to jam the rudder; unlike most modules the steering can be knocked out and repaired but is never permanently destroyed.

11,800

Effective HP

Base 36,200 HP plus everything Repair Party can restore: 0.01 of max HP per second (1%) × 20 s × 36,200 HP = 7,240 HP per charge, × 3 charges = 21,720 HP. Ceiling, not a prediction: a charge only restores damage actually taken, and only the regeneratable share of it. In practice ships realize about half of this, mostly because half the charges go unspent; a charge that is used returns about 97% of the per-charge figure above.

40,222–57,920

Repairable: penetration50%

Repairable: citadel10%

Repairable: steering gear50%

Bow section HP

Damage saturation pool for the bow: penetrations here deal their normal share until twice this much penetration damage has landed on the section (2 × 2,100 = 4,200), then further hits on it deal half damage. A penetration deals 0.33 × the shell's max damage; once the section is saturated it deals exactly half of that (0.5 × 0.33 = 0.165 × max damage), so a 3,000-damage shell's pen goes from 990 to 495. Overpens (0.1 × max damage) and citadels (1.0 ×) ignore saturation. Pens on the ship's other, unsaturated sections still deal the normal 0.33 ×. A larger pool keeps that part of the ship taking full damage for longer; a small one saturates fast and protects the ship's HP.

2,100

Casemate section HP

Damage saturation pool for the casemate: penetrations here deal their normal share until twice this much penetration damage has landed on the section (2 × 3,900 = 7,800), then further hits on it deal half damage. A penetration deals 0.33 × the shell's max damage; once the section is saturated it deals exactly half of that (0.5 × 0.33 = 0.165 × max damage), so a 3,000-damage shell's pen goes from 990 to 495. Overpens (0.1 × max damage) and citadels (1.0 ×) ignore saturation. Pens on the ship's other, unsaturated sections still deal the normal 0.33 ×. A larger pool keeps that part of the ship taking full damage for longer; a small one saturates fast and protects the ship's HP.

3,900

Hull section HP

Damage saturation pool for the hull: penetrations here deal their normal share until twice this much penetration damage has landed on the section (2 × 27,200 = 54,400), then further hits on it deal half damage. A penetration deals 0.33 × the shell's max damage; once the section is saturated it deals exactly half of that (0.5 × 0.33 = 0.165 × max damage), so a 3,000-damage shell's pen goes from 990 to 495. Overpens (0.1 × max damage) and citadels (1.0 ×) ignore saturation. Pens on the ship's other, unsaturated sections still deal the normal 0.33 ×. A larger pool keeps that part of the ship taking full damage for longer; a small one saturates fast and protects the ship's HP.

27,200

Superstructure section HP

Damage saturation pool for the superstructure: penetrations here deal their normal share until twice this much penetration damage has landed on the section (2 × 2,900 = 5,800), then further hits on it deal half damage. A penetration deals 0.33 × the shell's max damage; once the section is saturated it deals exactly half of that (0.5 × 0.33 = 0.165 × max damage), so a 3,000-damage shell's pen goes from 990 to 495. Overpens (0.1 × max damage) and citadels (1.0 ×) ignore saturation. Pens on the ship's other, unsaturated sections still deal the normal 0.33 ×. The superstructure is not exempt: it saturates exactly like the bow and stern, so shells aimed at it stop dealing full damage once this pool is used up. A larger pool keeps that part of the ship taking full damage for longer; a small one saturates fast and protects the ship's HP.

2,900

Stern section HP

Damage saturation pool for the stern: penetrations here deal their normal share until twice this much penetration damage has landed on the section (2 × 1,900 = 3,800), then further hits on it deal half damage. A penetration deals 0.33 × the shell's max damage; once the section is saturated it deals exactly half of that (0.5 × 0.33 = 0.165 × max damage), so a 3,000-damage shell's pen goes from 990 to 495. Overpens (0.1 × max damage) and citadels (1.0 ×) ignore saturation. Pens on the ship's other, unsaturated sections still deal the normal 0.33 ×. A larger pool keeps that part of the ship taking full damage for longer; a small one saturates fast and protects the ship's HP.

1,900

Citadel section HP

This section has no practical saturation cap: every hit here keeps dealing its normal share of damage (on most ships the citadel; on many destroyers the casemate).

No saturation cap

Main Battery

ModuleArtillery: 203 mm 3rd Year Type mod. C

Mounts / barrels5 mounts / 10 barrels

Reload time10.5 s

Firing range14.5 km

Turret traverse4 °/s

Turret armor25 mm

Turret traverse arcs

How far each mount can train, in degrees to either side of the mount's own facing. A rear turret with ±150° leaves a 60° blind wedge over the bow; one-sided arcs are wing mounts that cover a single side. The data does not say which way each mount faces, so the arcs are listed per mount without bow/stern angles.

2x ±150°, ±139°, ±128°, ±140°

Guns to bear

180° − 127° (the most restricted aft-facing mount's arc) = 53° off bow; 180° − 128° (the most restricted forward-facing mount's arc) = 52° off stern. How far off the bow (or stern) the ship must angle before every main turret can fire: the widest blind wedge among the rear-facing (or forward-facing) mounts, from each mount's trainable arc.

53° off bow / 52° off stern

See the firing-arcs diagram ↓

Shell Grouping (σ)2

Dispersion type

In practice: the baseline curve for a standard cruiser -- at max range (14.5 km) shells land in an ellipse about 133 m wide and 80 m tall. Also on this curve (215): AL Baltimore, AL Chapayev, AL Cheshire, AL Harbin, AL Montpelier, AL Tallinn, AL Zara, Aberdeen, Accord, Agano, Albemarle, Algérie and 203 more.

Standard cruiser

Max Horiz Disp

Horizontal dispersion ellipse width at max range, from the dispersion model:

σ_{H} = (\frac{R}{30} \cdot \frac{idealRadius - minRadius}{idealDistance} + minRadius) \cdot 30

= (\frac{14500}{30} \cdot \frac{8 - 1.1}{1000} + 1.1) \cdot 30 = 133.1 m

133.1 m at 14.5 km

Max Vert Disp

Vertical dispersion ellipse height at max range:

σ_{V} = σ_{H} \cdot radiusOnMax

= 133.1 \cdot 0.6 = 79.8 m

79.8 m at 14.5 km

Med Horiz Disp

50%-hit horizontal radius:

σ_{H, 50} = σ_{H} \cdot \frac{0.6}{σ}

= 133.1 \cdot \frac{0.6}{2} = 39.9 m

39.9 m at 14.5 km

Med Vert Disp

50%-hit vertical radius:

σ_{V, 50} = σ_{V} \cdot \frac{0.6}{σ}

= 79.8 \cdot \frac{0.6}{2} = 23.9 m

23.9 m at 14.5 km

Turret turn time

180 degrees / 4 deg/s traverse speed = 45 s.

45 s

Shells/min

10 broadside guns x 60 / 10.571 s (10.5 s = 74 ticks) base reload = 56.8.

56.8

HE shells

HE alpha2,500

HE Velocity840 m/s

Fire Chance10%

HE fire DPM vs T6 BB42443

Effective HE DPM vs T6 BB184335

HE penetration

34 mm ≈ 203 mm caliber / 6 (standard HE penetration ratio).

34 mm

HE full-salvo alpha

2,500 HE damage x 10 broadside guns = 25,000.

25,000

HE DPM

25,000 HE full-salvo alpha x 60 / 10.571 s (10.5 s = 74 ticks) base reload = 141,892.

141,892

Fires/min

56.8 shells/min × 0.1 (10% fire chance) = 5.68.

5.68

AP shells

AP alpha5,150

AP Velocity840 m/s

Min Ricochet55 deg

Guaranteed Ricochet70 deg

Fuse Timer0.033 s

Fuse Threshold34 mm

Improved AP FuseYes

AP overmatch

floor(203 mm caliber / 14.3) = 14 mm (AP auto-penetrates plating this thick or less).

14 mm

AP Pen Close

AP formula evaluated at muzzle velocity:

P = 10^{- 7} \cdot K \cdot m^{0.69} \cdot d^{- 1.07} \cdot v_{0}^{1.38}

= 10^{- 7} \cdot 2468 \cdot {125.85}^{0.69} \cdot {0.203}^{- 1.07} \cdot 840^{1.38} = 414.7 mm

414.7 mm point-blank

AP Pen Far

Same formula at the ship's max firing range (14.5 km), where the shell has slowed to 412.1 m/s:

P = 10^{- 7} \cdot 2468 \cdot {125.85}^{0.69} \cdot {0.203}^{- 1.07} \cdot {412.1}^{1.38} = 155.2 mm

155.2 mm at 14.5 km

AP full-salvo alpha

5,150 AP damage x 10 broadside guns = 51,500.

51,500

AP DPM

51,500 AP full-salvo alpha x 60 / 10.571 s (10.5 s = 74 ticks) base reload = 292,297.

292,297

AP AOE Radius

AP shell over-penetration splash radius; scales with shell mass. Wickes 102mm = 3, standard 152mm CL ~ 20, Iowa 406mm ~ 270, Yamato 460mm = 400, Incomparable 650mm = 550 (max). Larger value = bigger splash damage area when AP over-pens.

Torpedoes

ModuleTorpedoes: 610 mm triple

Launchers / tubes4 launchers × 3 tubes = 12 tubes

Reload time82 s

Projectile speed62.0 kt

Range9.99 km

Maximum simulated damage

Most targets only intersect one hull section, so a hit transfers about 1/3 of the warhead alpha (2/3 when the warhead blast >= 5000 and the burst reaches a second section). For this ship:

D_{sim} = α \cdot c = 47, 800 \cdot 0.333 = 15, 933

. In battle, a hit on the torpedo belt deals the per-hit figure × (1 − the target's torpedo protection %), a bow or stern hit deals it in full, and a torpedo never counts as a citadel hit.

≈ 15,933

Maximum damage (ammunition)

47,800 warhead alpha / 3 + 1,300 blast = 17,233. Warhead alpha / 3 plus the blast addend: the per-torpedo damage figure. The 'Maximum simulated damage' row above applies target geometry to the same warhead.

17,233

Torpedo module damage

Per-torpedo module/blast damage parameter. Most torpedoes carry 500 to 2,000; ships announced by WG as dealing increased module damage carry 9,000 to 12,000, so their hits knock out engines, rudders, and turrets far more often. Comparative figure.

1,300

Torpedo detectability1.6 km

Reaction time

How long a target has to dodge after your torpedo is spotted at its detectability range (lower means less warning):

t_{react} = \frac{1.6 km}{62 kt \times 2.6855} = 9.6 s

. 2.6855 converts knots to m/s on the game clock. Base value; commander torpedo-concealment skills lower it further.

9.6 s

Flooding chance

This torpedo carries a flooding-chance value of 2.87 per hit, shown as

2.87 \times 100 = 287 %

. Values above 100% are normal: in battle the base chance is scaled down by the target's torpedo protection (the Torp Reduction stat on its Survivability card) and any flood-resistance modifiers, so a value above 100% keeps flooding likely even through partial protection.

287%

Torpedo launcher traverse25 °/s

Launch arcswing 88° (one launcher per beam)

Torp Turn

Time to rotate the launchers 180 deg:

t_{turn} = \frac{180 °}{25 ° / s} = 7.2 s

7.2 s

Torp Arming197 m

Per-side salvo damage

One side firing, all torpedoes hitting: per-side tubes x per-torpedo simulated damage = 6 x 15,933 = 95,598. Each hit on the target's torpedo belt is reduced by its torpedo protection %.

95,598

AA Defense

AA mount points38

Maximum AA range

Longest-reaching family on the in-game AA card. Base AirDefense aura max range is 3.1 km; dual-purpose mount auras extend it.

5 km

25 mm Type96 mod. 14×3 25mm

25 mm/60 Type96 mod. 126×1 25mm

25 mm Type96 mod. 18×2 25mm

127 mm Type89 mod. A1 (DP)

Dual-purpose: your secondaries doing double duty against aircraft. The same mounts appear on the Secondary Battery card - shared guns, not extra hardware.

4×2 127mm

Guns127 mm Type89 mod. A1 (DP)

Continuous DPS

Effective DPS in in-game units (raw aura damage × 3.5 × hit probability, summed per contributing aura) - matches the Close-range AA DPS headline's currency. Includes 66 from dual-purpose secondaries firing as AA in this range band.

Range5 km

Guns25 mm Type96 mod. 1 + 25 mm/60 Type96 mod. 1

Continuous DPS

Effective DPS: 64 raw aura damage × 3.5 × 0.9 hit probability = 202 - the same in-game units as the Close-range AA DPS headline.

202

Range3.1 km

Total DPS in Aura

Far 66 + Medium 202 = 268

268

AA explosions

Each ~2 s salvo fires 2 AA explosions in quick succession, each leaving 2 clouds ahead of the attacking squadron - up to 4 clouds per salvo × 210 damage each. Planes that fly into a cloud take its damage; clouds dissipate before the next salvo lands. Defensive AA Fire, where fitted, multiplies the AA explosions within each salvo, and commander skills that raise the Number of AA explosions add to it.

2 per salvo, 2 clouds each

Cloud damage

Damage a plane takes for flying into one flak cloud, before any reductions.

210

Cloud spawn chance

Each cloud in the pattern rolls this chance to spawn, so salvos average fewer clouds than the maximum. Often called flak 'hit chance', but spawned clouds always damage planes that fly into them - the roll is on spawning.

90%

Salvo interval

A new flak salvo (the AA explosions above) fires roughly every 2 s.

every ~2 s

Fired by

Flak keeps firing while at least one secondary battery mount is operational - even losing every dedicated AA mount does not stop it.

Secondary battery

Flak zone

The activation band: flak fires while attacking planes are inside it. Clouds are placed ahead of the planes' path, so clouds can land short of 2.5 km or past 5 km - once planes get inside the band, new salvos stop. AA range bonuses push the outer edge out; the 2.5 km inner edge does not move.

2.5-5 km

See the AA layers diagram ↓

Secondary Battery

Mounts4

Firing range4.5 km

Shell Grouping (σ)1

Secondary DPM (per side)

Sum across all secondary families of (per-side barrels × 60 / reload_s × alpha), with each reload counted in whole 1/7 s ticks (guns fire on the first tick after the reload), where per-side barrels = mounts × barrels-per-mount / 2 (the guns that bear on one broadside target). Per-family: 4×2 127 mm (4/side) × 60/7.571 s (7.5 s = 53 ticks) × 2100 = 66,566. Assumes every shell hits (real hit rate is lower; the Brawl matchup tool on the Compare page folds in dispersion + target armor).

66,566

Secondary fire DPM vs T6 BB (per side)

Fires/min (per side) 2.5 × (1 − 0.3 fire resistance) × 60 s × 0.003 of max HP per second × 59,350 HP = 18,963. Per side: the barrels that bear on one broadside target (mounts × barrels / 2). A ceiling: assumes every shell hits and ignores the four-fire cap and Fire Prevention.

18,963

Total secondary DPM vs T6 BB (per side)

Secondary DPM (per side) 66,566 + secondary fire DPM 18,963 = 85,529: shell damage plus fire damage against one T6 battleship, every shell hitting.

85,529

127 mm Type89 mod. A1 (DP)

Dual-purpose: the same mounts also fire at aircraft, so they appear on the AA Defense card too - shared guns, not extra hardware.

4×2 127mm

Caliber127 mm

Reload time7.5 s

HE alpha2,100

Muzzle Velocity725 m/s

Fire Chance8%

Secondary fires/min (per side)

4×2 barrels / 2 sides × 60 / 7.571 s (7.5 s = 53 ticks) × 0.08 (8% fire chance) = 2.5. Per side: the barrels that bear on one broadside target (mounts × barrels / 2). A ceiling: assumes every shell hits and ignores the four-fire cap and Fire Prevention.

2.5

HE Pen21 mm

Secondary dispersion type

Max dispersion = range (km) × 57 + 30. Each dispersion type sets its own slope; this is not a percentage applied to a standard baseline.

Standard

Max secondary dispersion @ 4.5 km

4.5 km × 57 + 30 = 286.5 m.

286.5 m

Maneuverability

Engine power130,000 hp

Maximum speed35.0 kt

Turning circle radius780 m

Rudder shift time7.2 s

Engine power-boost threshold7.0 kt

Engine spool-up time15.3 s

Reverse spool-up time7.7 s

Reverse speed

top speed / 4 + 4.9 = 35 / 4 + 4.9 = 13.7 kt. Base value; speed modifiers scale it.

13.7 kt

Crash stop

Seconds from top speed to a dead stop after ordering full reverse: reverse power winds in over the reverse spool-up while water drag does most of the braking, using the ship's own reverse-power ratio. The full curve is on the acceleration chart. Full reverse stops about a quarter faster than a plain Stop order from top speed.

28.6 s

Engine boost threshold (reverse)

Speed below which the engine's built-in power boost applies in reverse.

9.7 kt

Acceleration 0-90%

Time to reach 90% of top speed (31.5 kt of 35.0 kt).

25.3 s

Acceleration 0-99%

Time to reach 99% of top speed (34.6 kt of 35.0 kt). 99% rather than 100% because true top speed is asymptotic (thrust meets drag), so the last fraction of a knot is never quite gained.

40.4 s

Guns in a full turn

With the rudder hard over the hull turns 5.5°/s, so a target drifts across the bow at that rate. Turret traverse minus hull turn: 4 − 5.5 = -1.5°/s, so the guns fall behind and catch up once the turn eases. Main Battery Mod. 2 (+20% traverse) and Mod. 3 (−15%) move this line.

fall behind by 1.5°/s

See the full acceleration curve ↓

Concealment

Detectability by sea

Base value, no camouflage. With a Grade IV permanent camo (or any disposable camo): 10.98 km x 0.955 = 10.49 km. Camouflage does not change detectability by air.

10.98 km

With Grade IV camouflage (sea)

Detectability by sea 10.98 km x 0.955 (Grade IV permanent camo or any disposable camo) = 10.49 km.

10.49 km

Detectability by air7.19 km

Smoke firing penalty6.06 km

Detect when firing (sea)

max(main battery range, sea detectability 10.98 km) = 14.5 km. Equal to the ship's main battery range (never below base detectability): firing makes you visible to everyone you can reach.

14.5 km

Detect when firing (air)

Air detectability 7.19 km + gun-firing bloom 4.06 km = 11.25 km. The bloom tracks main-battery caliber 203 mm × 0.020 = 4.06 km.

11.25 km

Detect when on fire (sea)

Sea detectability 10.98 km + 2.0 km while burning = 12.98 km.

12.98 km

Detect when on fire (air)

Air detectability 7.19 km + 3.0 km while burning = 10.19 km.

10.19 km

Guaranteed Detect2 km

✦

Consumables

Damage Control Party∞ charges · 60 s reload · 5 s active

Choose one

Sonar2 charges · 180 s reload · 94 s active · 4.2 km ship detect
ƒ
Derived from the consumable's 30 m grid-unit range (km = grid units x 30 / 1000): $\frac{140 \times 30}{1000} = 4.2 km$
· 2.97 km torpedo detect
ƒ
Derived from the consumable's 30 m grid-unit range (km = grid units x 30 / 1000): $\frac{99 \times 30}{1000} = 2.97 km$

Defensive AA Fire3 charges · 140 s reload · 25 s active · ×2 flak burst boost
ƒ
Repeats the flak burst pattern ×2 within each salvo - more clouds in the air over the salvo, at the same spots.

Catapult Fighter3 charges · 80 s reload · 70 s active · 5 km patrol radius
ƒ
Derived from the consumable's 30 m grid-unit range (km = grid units x 30 / 1000): $\frac{167 \times 30}{1000} = 5 km$
· 1 squadron size

Repair Party3 charges · 80 s reload · 20 s active · 7,240 HP (20% of max HP) total heal (per charge)
ƒ
0.01 of max HP per second (1%) × 20 s effective active time = 0.2 of max HP × 36,200 HP = 7,240 HP: up to 20% of max HP restored per charge.
· 21,720 HP (60% of max HP) total heal (all charges)
ƒ
0.2 of max HP per charge × 3 charges = 0.6 × 36,200 HP = 21,720 HP: up to 60% of max HP if the whole Repair Party loadout is used.
· 362 HP/s (1% of max HP) heal per second
ƒ
0.01 (1% of max HP) × 36,200 HP = 362 HP/s. WoWS heals a flat percent of MAX HP each second, so this rate holds at any health level.

Under the hood

Show ▾

All values are ship base stats with modifications and upgrade changes denoted inline.

The constants behind the formulas and the long tail: shell and dispersion inputs, fixed-range anchors, salvo math, layered AA. Click the formula chip on any row to see how it is calculated.

Main battery formulas

vs standard cruiserStandard

The standard cruiser dispersion curve.

Shell scatter width @ 5 km67.5 m

(166.7 × (8 − 1.1) / 1000 + 1.1) × 30 = 67.5 m. Horizontal scatter at a fixed 5 km, from the same dispersion model as the rows below - a knife-fight-range anchor comparable across ships.

Shell scatter width @ 10 km102 m

(333.3 × (8 − 1.1) / 1000 + 1.1) × 30 = 102 m. How wide your shells scatter at 10 km, from the same dispersion model as the max-range figure above. Picking a fixed range makes this number directly comparable from ship to ship: max-range dispersion makes a longer-range gun look worse even when it's tighter at any common range. The interactive Dispersion tab on the Charts card plots the full curve from 0 to max range.

Shell scatter height @ 5 km27.5 m

How tall the scatter ellipse is at a fixed 5 km, from the same model, comparable from ship to ship. The height/width ratio is a piecewise-linear curve through three points from the ship's own dispersion data:  $radiusOnZero = 0.2$  at 0 m,  $radiusOnDelim = 0.5$  at  $delim \cdot R_{m a x} = 0.5 \cdot 14500 = 7250$  m, and  $radiusOnMax = 0.6$  at 14500 m. Below the kink:  $k = 0.2 + (0.5 - 0.2) \cdot \frac{5000}{7250} = 0.4069$ , so  $σ_{V} = σ_{H} \cdot k = 67.5 \cdot 0.4069 = 27.5 m$ .

Shell scatter height @ 10 km54.9 m

How tall the same scatter ellipse is at 10 km. Comparable from ship to ship for the same reason as the width value above. The height/width ratio is a piecewise-linear curve through three points from the ship's own dispersion data:  $radiusOnZero = 0.2$  at 0 m,  $radiusOnDelim = 0.5$  at  $delim \cdot R_{m a x} = 0.5 \cdot 14500 = 7250$  m, and  $radiusOnMax = 0.6$  at 14500 m. Above the kink:  $k = 0.5 + (0.6 - 0.5) \cdot \frac{10000 - 7250}{14500 - 7250} = 0.5379$ , so  $σ_{V} = σ_{H} \cdot k = 102 \cdot 0.5379 = 54.9 m$ .

AP pen 5 km288 mm

AP penetration at a fixed 5 km, from the same ballistic curve as AP Pen Close/Far: the shell's impact velocity at that range fed through the AP formula  $P = 10^{- 7} \cdot K \cdot m^{0.69} \cdot d^{- 1.07} \cdot v^{1.38}$   $= 10^{- 7} \cdot 2468 \cdot {125.85}^{0.69} \cdot {0.203}^{- 1.07} \cdot {644.6}^{1.38} = 288 mm$ , where 644.6 m/s is the shell's speed when it arrives at 5 km (from 840 m/s at the muzzle). Fixed anchors make ships directly comparable at the same fighting distance; the Charts card plots the full curve.

AP pen 10 km203 mm

AP penetration at a fixed 10 km, from the same ballistic curve as AP Pen Close/Far: the shell's impact velocity at that range fed through the AP formula  $P = 10^{- 7} \cdot K \cdot m^{0.69} \cdot d^{- 1.07} \cdot v^{1.38}$   $= 10^{- 7} \cdot 2468 \cdot {125.85}^{0.69} \cdot {0.203}^{- 1.07} \cdot {500.7}^{1.38} = 203 mm$ , where 500.7 m/s is the shell's speed when it arrives at 10 km (from 840 m/s at the muzzle). Fixed anchors make ships directly comparable at the same fighting distance; the Charts card plots the full curve.

AP flight time @ 10 km5.67 s

How long an AP shell takes to reach a target at a fixed 10 km, from the same numerically integrated trajectory the Charts card plots. The shell slows under quadratic air drag,  $a_{drag} = k ρ v^{2}$ , where  $ρ$  is air density from a standard-atmosphere profile and  $k$  bundles the shell's drag coefficient, caliber and mass:  $k = \frac{π C_{d} d^{2}}{8 m} = \frac{π \cdot 0.337 \cdot {0.203}^{2}}{8 \cdot 125.85} = 4.33 \times 10^{- 5}$ . That runs from a 840 m/s muzzle velocity in 0.02 s steps under gravity 9.8 m/s² until the shell lands, then divides by 2.77 because the game clock runs faster than real time. Lower is better, since a faster shell is harder to dodge and needs less lead.

HE flight time @ 10 km5.67 s

How long an HE shell takes to reach a target at a fixed 10 km, from the same numerically integrated trajectory the Charts card plots. The shell slows under quadratic air drag,  $a_{drag} = k ρ v^{2}$ , where  $ρ$  is air density from a standard-atmosphere profile and  $k$  bundles the shell's drag coefficient, caliber and mass:  $k = \frac{π C_{d} d^{2}}{8 m} = \frac{π \cdot 0.337 \cdot {0.203}^{2}}{8 \cdot 125.85} = 4.33 \times 10^{- 5}$ . That runs from a 840 m/s muzzle velocity in 0.02 s steps under gravity 9.8 m/s² until the shell lands, then divides by 2.77 because the game clock runs faster than real time. Lower is better, since a faster shell is harder to dodge and needs less lead.

Guns per full salvo (alpha, DPM)10

5 mounts × 2 barrels = 10; all 10 bear on the broadside.

Model inputs

Krupp (AP)2,468

Armor-penetration constant of the AP shell; penetration scales straight with it, so a 10% higher Krupp is 10% more penetration at every range.

AP shell mass125.85 kg

Enters penetration as mass^0.69 and slows the shell's drag deceleration, so a heavier shell keeps more velocity at range.

AP drag coefficient0.337

Air drag on the AP shell in flight; lower keeps velocity, and with it penetration, at long range.

AP muzzle velocity840 m/s

Starting speed of the AP shell; penetration scales with velocity^1.38.

HE muzzle velocity840 m/s

Starting speed of the HE shell; sets its flight time and lead.

idealRadius8

Horizontal dispersion growth per idealDistance of range, in 30 m units; the slope of the scatter-width line.

minRadius1.1

Horizontal dispersion at zero range, in 30 m units; the intercept of the scatter-width line.

idealDistance1,000 m

Range step over which horizontal dispersion grows by idealRadius.

taperDist4,000 m

Inside this range the scatter width tapers toward minRadius instead of following the line.

radiusOnZero0.2

Vertical scatter as a share of horizontal at zero range.

radiusOnDelim0.5

Vertical scatter as a share of horizontal at the delim point.

radiusOnMax0.6

Vertical scatter as a share of horizontal at maximum range.

delim0.5

Where the vertical-scatter curve bends, as a share of maximum range.

Torpedoes

Estimated torpedo reaction time9.6 s

1600 m / (62.0 kt × 2.6855) = 9.6 s. detectability / (speed kt x 2.6855 m/s per knot on the game clock).

Torpedo speed62.0 kt

Travel time to max range60 s

9990 m / (62.0 kt × 2.6855) = 60 s. range / (speed kt x 2.6855 m/s per knot on the game clock).

Tube count12

4 launchers × 3 tubes.

Per-side salvo6 torpedoes

12 wing tubes / 2 = 6: the launchers sit one per beam, so only half of them reach any one side. Each launcher reloads on its own, so she can fire one beam, turn, and fire the other without waiting.

Full-salvo damage191,196

All tubes hitting one target: tubes x per-torpedo simulated damage = 12 x 15,933 = 191,196. Each hit on the target's torpedo belt is reduced by its torpedo protection %.

AA defense

AA DPS at max range66

Only families that reach 5 km contribute at the outer edge of the AA bubble. In-game families: 25mm Type96 4x3 -> 21 DPS @ 3.1 km; 25mm Type96 single 26x1 -> 138 DPS @ 3.1 km; 25mm Type96 double 8x2 -> 42 DPS @ 3.1 km; 127mm40 Type89 3 4x2 -> 66 DPS @ 5 km.

AA DPS layered by range66 DPS @ 5 km, 267 DPS @ 3.1 km

@ 5 km: 66 from one family; @ 3.1 km: 21 + 138 + 42 + 66 = 267. Cumulative AA DPS at each family range threshold. Inner ranges stack the outer families, so a target closing the distance hits stronger AA bubbles as it crosses each band.

AA DPS at point-blank267

21 + 138 + 42 + 66 = 267 DPS: the sum of every family's average DPS, achievable only inside the closest-range family (3.1 km).

AA threat index953

21 × 3.1 + 138 × 3.1 + 42 × 3.1 + 66 × 5 = 953. SUM over AA auras of (aura DPS x aura range km). A plane crossing the AA bubble is exposed to each aura for a time proportional to that aura's range, so long-reach DPS is worth more than the same DPS in a short bubble. Units: DPS*km; used to rank overall AA threat across the cohort.

Secondary battery firepower

Max HE alpha2100

The only family (127 mm): 2100. Maximum HE damage per shell across secondary HE families. Best on this ship: 2100 from the 127 mm family.

Max HE fire chance8%

The only family (127 mm): 8%. Maximum per-shell fire chance across secondary HE families (before target fire resistance is applied). Best on this ship: 8% from the 127 mm family.

Max HE pen21 mm

The only family (127 mm): 21 mm. Maximum HE armor penetration across secondary HE families (caliber × 1/6 for most nations; 1/4 for German/UK BBs). Shells whose pen falls under a plate's armor thickness shatter for 0 hull damage though fire chance still applies. Best on this ship: 21 mm from the 127 mm family.

Open in Charting Tool

Ship Charts

Background

A Myōkō class heavy cruiser with exceptional reconnaissance abilities. She can detect even the quietest sounds and acts as an effective spotter for Myōkō's long-range weaponry. This warship is modeled on heavy cruiser Nachi as she appears in "Arpeggio of Blue Steel -ARS NOVA-." © AP / SG, Ap

Armor Beta

Hull HP 36,200, distributed across 5 hull zones, each with its own plate thicknesses, saturation cap, and pen thresholds. HP caps are estimates.

Bow & stern16 mm

Overmatched by 126+ AP guns across the bracket. Can’t reliably bow-tank; gets bow-citadelled and overpenned.

Belt / citadel102 mm

Thin belt: battleship AP citadels straight through it broadside. Rely on angle, speed and concealment, never sit flat.

Farming6 mm

Superstructure and extremities take HE pens and AP overpens from nearly any gun: steady chip damage. Fire resistance 30%, fires burn 30s. Range-by-range in the Compare tool →

Section	Plates	HP cap	Threats	Tactic
Bow	16 mm primary (range 16–30 mm)	≈ 1,810 (~5% of HP)	Overmatched by 283mm+ AP (Graf Spee, Scharnhorst)Angle bounces 203mm16 mm: HE pens from 127mm+	Bow-tank fits behind this exterior plate. Saturation is FAST here; the cap is often only a few thousand HP.
Hull (midship)	32 mm primary (range 6–89 mm)	≈ 27,150 (~75% of HP)	Overmatch not possible in its bracketAngle bounces 410mm32 mm: HE pens from 203mm+	Largest HP pool. Citadel sits behind these plates; thinner deck and side plating absorb the rest.
Stern	16 mm primary (range 16–50 mm)	≈ 1,810 (~5% of HP)	Overmatched by 283mm+ AP (Graf Spee, Scharnhorst)Angle bounces 203mm16 mm: HE pens from 127mm+	Mirror of bow. Same fast saturation.
Citadel	102 mm primary (range 19–102 mm)	no cap	Citadel pen: full damageOver-pen: ×0.10 damage	Effectively no cap; citadel pool sits at ~165k HP on every ship. An AP citadel penetration deals the shell's full damage, the biggest single hit available; only over-penetrations are damped, to ×0.10.
Superstructure	6 mm primary (range 6–25 mm)	no cap	Any HE ≥16 mm pens at full damage	Any HE ≥16 mm pens at full damage. HE-spam target, and the section saturates fast (often only a few thousand HP).

Saturation cap = HP a section can absorb before further damage to it is reduced (the "bow-tank" effect). Citadel pool is ~165k on every ship (effectively no cap); damage is gated by pen/over-pen multipliers instead. Superstructure saturates fast but HE always pens regardless of the plate thickness. Rudder (and other module HPs) are a separate pool from ship HP: damaging a module doesn't drain ship HP. Incapacitated modules like the rudder and engine are restored by DCP, but secondary and AA mounts destroyed at 0 HP stay out for the rest of the battle.

Balance History

Balance updates affecting ARP Nachi. Cards are condensed; use each source link for full context.

Buff ×6Main Battery ×3Consumable ×3

2026-04-30

Ministry of Balance: Viva la Marina!

Main battery firing range increased from 13.8 to 14.5 km.
Main battery reload time reduced from 12 to 10.5 s.
Main battery AP shell ricochet angles increased from 45/60 to 55/70 degrees.
Improved Repair Party:
Number of charges increased from 2 to 3.
HP regeneration speed increased from 0.7 to 1% per second.

Read the full official post

Exteriors

Skins & permanent camouflages

Every custom exterior ARP Nachi can equip.

DefaultThe ship’s standard exterior

Primary official WG sources

Filtered to official World of Warships: Legends pages where this ship is a focus, reward, line member, or high-context variant mention.

2023-10-02 · Official ship feature / stats Arpeggio of Blue Steel is Back! Variant source 2025-01-23 · Patch notes February Update: Legendary Pilgrimage Patch notes 2026-04-30 · Patch notes May Update: From Rome to Edo Patch notes

ARP Nachi

ARP Nachi Community Stats

ARP Nachi Community Stats

ARP Nachi Community Stats

Playstyle

Overview

Positioning

Potato Avoidance

Signature Traits →

How to get ARP Nachi

Best listed chance for this ship

Builds

Cohort position

Peers in this cohort

Stats & specs

Under the hood

Main battery formulas

Model inputs

Torpedoes

AA defense

Secondary battery firepower

Ship Charts

Background

Armor Beta

Balance History

Ministry of Balance: Viva la Marina!

Skins & permanent camouflages

Primary official WG sources

Signature Traits