The ropes are the strongest part of the pilot ladder. Since the rope material is manila rope, it is very vulnerable and sensitive to salt and water. Special care should therefore be taken when stowing the pilot ladder during the sea voyage.
As per ISO 799 the following requirements apply to the side ropes:
- Manilla rope as per ISO 1181:2004 or similar
- Rope’s breaking strength is 24 KN, with a diameter of 20 mm.
- Metals used for clamping and fastening shall be corrosion resistant
- The side ropes are continuous loops with the joint above the top step or below the bottom step only.
- When the ladder is in use, the ropes cannot come in contact with the ship’s hull.
The ropes are the strongest parts of the pilot ladder, rated at 24 kN each.
There are 2 double side ropes on each side of the ladder. That makes the total strength 2 x 48 kN. The ropes should be the only part of the ladder to carry the static and dynamic weight of the ladder. These forces should never be transferred to the ship’s deck via wooden parts of the ladder, or uncertified strong points on deck, such as railings and pipes. That’s why shackles and tongues on deck should not be used to secure the pilot ladder. Use only designated strong points !
The soft material of which the ropes are made requires soft edges in way of the pilot access point over which the pilot ladder is hanging overboard. Once again, this both to enhance safety as well as the ladder’s lifespan.
IMO 1045(27) Pilot Transfer Arrangements:
2.2.1 The side ropes of the pilot ladder should consist of two uncovered ropes not less than 18 mm in diameter on each side and should be continuous, with no joints and have a breaking strength of at least 24 Kilo Newtons per side rope. The two side ropes should each consist of one continuous length of rope, the midpoint half-length being located on a thimble large enough to accommodate at least two passes of side rope.2
2.2.2 Side ropes should be made of manila or other material of equivalent strength, durability, elongation characteristics and grip which has been protected against actinic degradation and is satisfactory to the Administration.
2.2.3 Each pair of side ropes should be secured together both above and below each step with a mechanical clamping device properly designed for this purpose, or seizing method with step fixtures (chocks or widgets), which holds each step level when the ladder is hanging freely. The preferred method is seizing.1
1Refer to the recommendations by the International Organization for Standardization, in particular publication ISO 799:2004, Ships and marine technology — Pilot ladders, part 4.3a and part 3, paragraph 3.2.1.