Hull and Outfitting

Appendages - Rudders

Save PDF

Appendages - Rudders

Save PDF

Last UpdatedDec 18, 2025
1 minute read

Rudder information provided on this page is required for manoeuvring calculations only.

Number	Number of rudders.
Type	A Conventional, Becker or Schilling rudder may be selected. Note: The manoeuvring calculations are based on two theories, one for Merchant and the other for Naval vessels. The theory for merchant vessels assumes a Conventional rudder. Therefore, if you select a Merchant Vessel, then the rudder type is ignored and a Conventional rudder is assumed.
Turn rate	Rudder turning rate in degrees/sec.
Aspect ratio	Aspect ratio of the rudders.
Height	Rudder height (in input units).
Distance aft of AP	The distance from the Aft Perpendicular to the rudder stock.
Planform Area	The projected area of a single rudder.

Depending on ship type as specified on the Manoeuvring Data - General page, the following limits are applied to the input data:

		Minimum Value	Maximum Value
Limits for Naval Ships
	No. of Rudders	1	2
	Rudder Area / Length*Draft (AR/LT)	-	0.075
	Rudder Height	0.75*Prop Diam	Mean Draft+Trim
	Aspect Ratio	0.75	2.80
	Rudder Rate [deg/s]	1.0	7.0
Limits for Merchant Ships
	No. of Rudders	1	4
	Rudder Area/Length*Draft (AR/LT)	-	0.075
	Rudder Height	0.75*Prop Diam	Mean Draft+Trim
	Aspect Ratio	0.75	2.80
	Rudder rate [deg/s]	1.0	7.0

Note:
These limits are not checked until manoeuvring calculations are performed, at which point a dialog is displayed indicating which limits have been exceeded.

Hull and Outfitting

Appendages - Rudders

Table of Contents

Appendages - Rudders

Related Links