Hedgehog (Initial Model)

[Edit] Hedgehog (Initial Model) No.439 Hedgehog(初期型)
Depth Charge Effects: -1 +18 +3 Scrap value: 1 13 1 2 (Unbuildable)
Refittable Ship Types
Coastal Defense Ship	Destroyer
Light Cruiser	Torpedo Cruiser
Heavy Cruiser	Training Cruiser
Aviation Cruiser	Fast Battleship
Battleship	Aviation Battleship
Light Carrier	Standard Aircraft Carrier
Armored Carrier	Seaplane Tender
Submarine	Aircraft Carrying Submarine
Submarine Tender	Fleet Oiler
Repair Ship	Amphibious Assault Ship

Introduction

紅茶の国が開発した強力な対潜兵装です。
対潜爆雷に代替する次世代の対潜兵装として開発された、前方投射式の多弾散布型の対潜迫撃砲です。
ハリネズミと呼ばれたこの革新的な新型対潜兵装は、比較的シンプルな構造でありながら対潜戦闘に大きな進化をもたらし、改良を施されつつ戦後の艦艇にも装備運用されていきます。

A powerful anti-submarine weapon developed by the Country of Tea.
It's a next-generation anti-submarine weapon designed to replace depth charges. It's a forward-projecting multi-round anti-submarine mortar.
This innovative new anti-submarine weapon is known as the Hedgehog. It has a simple construction but it's a revolution in anti-submarine warfare. After some upgrades, it was deployed aboard post-war ships.

Mechanics

Depth Charges are one of the main equipment used for ASW, greatly enhancing ASW Damage Synergy. Their main stat is "ASW" .

ASW Damage Synergy
Small Small Sonars	Type 93 Passive Sonar Type 4 Passive Sonar Type 3 Active Sonar Type 3 Active Sonar Kai Type124 ASDIC Type144/147 ASDIC HF/DF + Type144/147 ASDIC
Large Large Sonars	Type 0 Passive Sonar
DCP Depth Charge Projectors (DCP)	Type 94 Depth Charge Projector Type 3 Depth Charge Projector Type 3 Depth Charge Projector (Concentrated Deployment) Prototype 15cm 9-tube ASW Rocket Launcher RUR-4A Weapon Alpha Kai AP Mk.32 ASW Torpedo (Mk.2 Thrower) AP
DCR Depth Charge (Racks) (DCR)	Type 95 Depth Charge AP Type 2 Depth Charge AP Lightweight ASW Torpedo (Initial Test Model) AP Hedgehog (Initial Model) AP Type 2 Depth Charge Kai Ni AP
Other ASW Mortars	Type 2 12cm Mortar Kai Type 2 12cm Mortar Kai (Concentrated Deployment)
ASW Damage Modifiers: [math]\displaystyle{ \text{Mod}_\text{synergy} = {Mod}_\text{1} \times {Mod}_\text{2} }[/math]
[math]\displaystyle{ {Mod}_\text{1} }[/math]	+ (Any Sonar + Any Depth Charge)	1.15
[math]\displaystyle{ {Mod}_\text{2} }[/math]	DCP + DCR and NO Small	1.1
	Small + DCP + DCR	1.25
Examples
[math]\displaystyle{ \text{Mod}_\text{synergy} }[/math]	Small + DCP + DCR	1.4375[math]\displaystyle{ 1.15 \times 1.25 }[/math]
	Large + DCP + DCR	1.265[math]\displaystyle{ 1.15 \times 1.1 }[/math]
Armor Penetration
Indepentant of synergies, some equipment provides additional armor penetration to ASW attacks. The affected equipment are: DCR: Type 95 DC, Type 2 DC, Lightweight ASW Torpedo, Hedgehog, Type 2 DC K2 DCP: RUR-4A Weapon Alpha Kai, Mk.32 ASW Torpedo (Mk.2 Thrower). The flat armor penetration value is calculated as follows: [math]\displaystyle{ \text{Pen} = \sum\limits_{\text{Equipment}} \Big( \sqrt{\text{ASW}_\text{Equipment} - 2} + \text{Mod}_\text{ship} \Big) }[/math] With [math]\displaystyle{ \text{ASW}_\text{Equipment} }[/math] the base ASW stat of the applicable equipment, Visible Bonuses and Improvements are not counted here. [math]\displaystyle{ \text{Mod}_\text{ship} }[/math] being 1 for DE, 0 otherwise, Note Armor penetration from equipment stacks, The final armor of the targetted submarine cannot go below 1.

Notes

How To Obtain

From quest: F112

Ranking reward for:

• Sep 2021: 1-5
• Dec 2021: 1-5 (★+2), 6-20, 21-100, 101-500

Event reward for:

• Fall 2021 Event E-1: Hard (★+2), Medium

Updates History

• 2021-10-29: Implemented as Event Reward

Fit Bonuses

Ship	Extra Requirement								Note
US Ships British Ships					+3			+1	One-time
Matsu-class Coastal Defense Ships (DE)					+2			+1	One-time
Other Destroyers Other Light Cruisers Training Cruisers					+1			+1	One-time

Improvement

Improvement effects
	1★	2★	3★	4★	5★	6★	7★	8★	9★	Max★
	0.75	1.06	1.29	1.50	1.67	1.83	1.98	2.12	2.25	2.37
	0.67	0.94	1.15	1.33	1.49	1.63	1.76	1.89	2.00	2.11