M43M43(1982)(cont)(Rev.1
Feb 2024)

Bridge control of propulsion machinery forunattended machinery spaces
M43.1
Under all sailing conditions, including manoeuvring, the speed, direction of thrust
and, if applicable, pitch of the propeller shall be fully controllable from the navigating bridge.
M43. 21 In principle tThe remote control for propulsion machinery mentioned under M43.1 isto be provided performed by a single control device for each independent propeller, withautomatic performance of all associated services including, where necessary, with means ofpreventing overload and prolonged running in critical speed ranges of the propellingmachinery.
M43. 32 The bridge control system is to be independent from the other transmission system;
however, one control lever for both system may be accepted.
M43. 43 Operations following any setting of the bridge control device including reversing
from the maximum ahead service speed in case of emergency are to take place in an
automatic sequence and with time intervals acceptable to the machinery.
M43.5
The main propulsion machinery shall be provided with an emergency stopping
device on the navigating bridge and independent from the bridge control system.
M43. 64 Remote starting of the propulsion machinery is to be automatically inhibited if
conditions exist which may hazard the machinery, e.g. shaft turning gear engaged, drop oflubricating oil pressure.

Note:
1. Rev.1 of this UR is to be uniformly implemented by IACS Societies on vessels contracted
for construction on or after 1 January 2025.
2. The “contracted for construction” date means the date on which the contract to build thevessel is signed between the prospective owner and the shipbuilder. For further details
regarding the date of “contract for construction”, refer to IACS Procedural Requirement(PR) No. 29.

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IACS Req. 1986/Rev.1 2024

M43M43(cont)M43.75 For steam turbines a slow-turning device should is to be provided which operates
automatically if the turbine is stopped longer than admissible. Discontinuation of thisautomatic turning from the bridge must be possible.
Note:
For attended machinery spaces, the slow turning device may be arranged to beoperated manually.
M43.86 For SOLAS Convention ships, Regulation II-1/49.5 applies. For ships not coveredby the SOLAS Convention, Tthe design of the bridge control system shall is to be such that incase of its failure an alarm is given. In this case the speed and direction of the propeller thrust
is to be maintained until local control is in operation, unless this is considered impracticable.
In particular, lack of power (electric, pneumatic, hydraulic) should will not lead to major andsudden change in propulsion power or direction of propeller rotation.
M43.9
The number of automatic consecutive attempts which fail to produce a start shallbe limited to maintain sufficient starting air pressure. An alarm shall be provided at an airpressure level, which still permits main engine starting operation.
M43.10 It shall be possible for the propulsion machinery to be controlled from a local
position even in the case of failure in any part of the automatic or remote control systems.
M43.11 Remote control of the propulsion machinery shall be possible only from one control
location at one time; at such locations interconnected control positions are permitted.
M43.12 The control system shall include means to prevent the propelling thrust fromaltering significantly when transferring control from one control to another.
M43.13 Each control location is to be provided with means to indicate which of them is incontrol. Propolusion machinery orders from the navigating bridge shall be indicated in theengine control room or at the manoeuvring platform, as appropriate.
M43.14 The transfer of control between the navigating bridge and machinery spaces shallbe possible only in the main machinery space or the main machinery control room.
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IACS Req. 1986/Rev.1 2024