Improving Ship Speed

Introduction

By equipping a Turbine and an Engine it's possible to make fast destroyers like Shimakaze go speeds far beyond fast. As shown here, using a Improved Steam Turbine and a New High Pressure-Temperature Steam Boiler will result in Shimakaze going to Fastest

Speed represents the speed of a ship girl. Ship girls are either slow (低速) or fast (高速) by default. As of the 10 Jan 2017 Update, ship girl speed can be further increased to fast+ (高速+) or fastest (最速) by using a combination of Improved Steam Turbine, Enhanced Steam Boiler or New High Pressure-Temperature Steam Boiler.

Overview

By equipping a Turbine and an Engine it's possible to make Battleship like Yamato go from slow to fast. As shown here, using a Improved Steam Turbine (shown in the expansion slot) and an Enhanced Steam Boiler will result in Yamato going to Fast allowing her access to path branching she would otherwise not have access to when she was Slow.

There are several effects of increasing ship girl speed:

• Meeting routing requirements.
  • Slow ships can be sped up to fulfil certain branching requirements.
    • Note that this does not apply to ship type requirements. Eg a BB will not count as a FBB where FBBs are specifically required.
  • Fast+ and fastest are required to fulfil routing requirements in some maps. Eg. 3-2 and 4-5.
• Combined Fleet composition.
  • Slow battleships that are fast+ can be placed in the escort fleet.
• Evasion increase.
  • Although this has been stated by the developers to occur, testing has not shown any significant increase in evasion.
• Because Destroyer Escorts cannot be equipped with a turbine, they are the only ship type that cannot be sped up.

Speed Change Charts

It is highly recommended that you have a Reinforcement Expansion on ship girls that you wish to speed up. It can severely degrade their combat efficiency if you attempt to speed up ship girls without one.

• Enhanced Steam Boiler = ESB
• New High Pressure-Temperature Steam Boiler = NHTSB

All synergies listed below already include 1 Improved Steam Turbine because it is an absolute requirement for speed ups.

Ship Speed Group		Minimum Speed Up Requriement						Notes
		Fast		Fast+		Fastest
		ESB	NTHSB	ESB	NTHSB	ESB	NTHSB
Fast	A	-	-	1	-	2	-
						-	1
	B1	-	-	1	-	1	1
	B2	-	-	1	-	-	2	Also becomes fastest with 3+ ESB and 1 NTHSB with 2+ ESB but requires too many slots to be useful.
	C	-	-	1	-	-	-	Unable to be sped up to fastest.
Slow	A	1	-	1	1	2	1	Can also attain fastest with 2+ ESB with 1 NHTSB but requires too many slots to be useful.
				-	2	1	2
				-	-	-	3
	B	-	2	-	-	-	-	Unable to be sped up to fastest. Can also attain fast+ with 3+ ESB, 2+ ESB with 1 NHTSB, and 1+ ESB with 2+ NHTSB but requires too many slots to be useful.
	C	-	1	-	-	-	-	Unable to be sped up beyond fast.

Ship Speed Group		Ship Name/Class/Type
		Destroyer	Light Cruiser	Heavy Cruiser	Battleship	Carrier	Auxiliary
Fast	A	Shimakaze · Tashkent		Mogami-class · Tone-class		Taihou · Shoukaku-class
	B1	Amatsukaze	Agano-class		Kongou-class · Iowa	Souryuu · Hiryuu · Unryuu · Amagi
	B2	Other DD	Other CL · CLT	Other CA	Other FBB	Fast CVL · Other CV
	C		Yuubari			Kaga	Fast AV
Slow	A				Yamato-class
	B		CT		Other BB/V · Gangut	Slow CVL	Slow AV · Taigei
	C						SS/V · Akitsumaru · Akashi · AO