Hello all,
Under what circumstances is an inclining experiment necessary after a major retrofit - according to Class Rules?
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This excerpt is from the RINA Rules Pt B, Ch 3, Sec 1 (see bold highlight). Same applies to all classification societies.
3.2.3 Inclining test (1/7/2019)
The inclining test is required in the following cases:
• Any new passenger ship regardless of size and any new
cargo ship having length of 24 m and upwards, after its
completion, except for the cases specified in [3.2.4]
• Any ship, if deemed necessary by the Society, where any
alterations are made so as to materially affect the stabil-
ity. For a ship in service which undergoes alterations
with calculable differences in lightship properties which
materially affect the stability information supplied to the
master, an inclining test can be avoided if:
- the deviation of lightship displacement does not
exceed 2% of the original approved lightweight or 2
tonnes, whichever is greater; and
- the deviation of lightship longitudinal centre of grav-
ity from the original does not exceed 1% of the LBP
of the ship.
Where the deviation exceeds both or one of the above
limits, an inclining test is to be carried out.
Where a ship is within both the above limits, even if the
inclining test can be avoided, the calculated values of
lightweight, lightship LCG and lightship VCG are to be
used in all subsequent stability information supplied to
the master.
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Hello all,
The IACS UI SC 297 provides an interpretation of SOLAS chapter II-1, regulations 5.4 and 5.5 (as amended by resolution MSC.421(98)) and of resolution MSC.429(98)/Rev.1 and Rev.2, Explanatory Notes.
When alterations are made to a ship in service that result in calculable differences in the lightship properties, a detailed weights and centres of gravity calculation to adjust the lightship properties should be carried out. If the adjusted lightship displacement or longitudinal centre of gravity, when compared to the approved values, exceeds one of the deviation limits specified in SOLAS II-1 regulation 5.5, the ship should be re-inclined.
In addition, if the adjusted lightship vertical centre of gravity, when compared to the approved value, exceeds 1%, the ship should be re-inclined. The lightship transverse centre of gravity is not subject to a deviation limit.
Reference: ui-sc297 (1).pdf (178.5 KB)
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Thank you @Plimsoll this is very useful!
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