7 Rescue Boats and Fast Rescue Boats

  7.1.2 The maximum towing force of the rescue boat should be determined. This information should be used to determine the largest fully loaded liferaft the rescue boat can tow at two knots. The fitting designated for towing other craft should be secured to a stationary object by a tow rope. The engine should be operated ahead at full speed for a period of at least 2 min, and the towing force measured and recorded. There should be no damage to the towing fitting or its supporting structure. The maximum towing force of the rescue boat should be recorded on the type approval certificate.

  7.1.3 The rigid rescue boat should be fitted with its engine and all its equipment. The number of persons for which the rescue boat is to be approved, having an average mass of at least 82.5 kg and all wearing lifejackets and immersion suits and any other essential equipment required should then board; one person should lie down on a stretcher of similar dimensions to those shown in figure 4 and the others should be properly seated in the rescue boat. The rigid rescue boat should then be manoeuvred and all equipment on board tested to demonstrate that it can be operated without difficulty or interference with the occupants.

Figure 4 Stretcher dimensions (mm)

  7.1.4 The boat should be loaded with properly distributed load of four times the weights to represent the equipment and full complement of persons, each weighing 82.5 kg, for which it is to be approved and suspended for five minutes from its bridle or hooks. The weights should be distributed in proportion to the loading of the boat in its service condition, but the weights used to represent the persons need not be placed 300 mm above the seat pan. The boat and bridle or hooks and fastening device should be examined after the test has been conducted and should not show any signs of damage. Testing by filling the boat with water should not be accepted. This method of loading does not give the proper distribution of weight. Machinery may be removed in order to avoid damage, in which case weights should be added to the boat to compensate for the removal of such machinery.

  7.1.5 Operation of engine and fuel consumption test

The boat should be loaded with weights equal to the mass of its equipment and the number of persons for which the boat is to be approved. The engine should be started and the boat manoeuvred for a period of at least 4 h to demonstrate satisfactory operation.

The boat should be run at a speed of not less than 6 knots for a period which is sufficient to ascertain the fuel consumption and to establish that the fuel tank has the required capacity.

  7.1.6 Speed and manoeuvring trials should be carried out with engines of various powers to assess the rescue boat's performance (if a rigid rescue boat is equipped with outboard motor).

  7.1.7 It should be demonstrated that both with and without engine and fuel or an equivalent mass in place of the engine and fuel tank, the rescue boat is capable of being righted by not more than two persons if it is inverted on the water. In the case of fast rescue boats which are not self-righting, the engine should be running in neutral position and, after stopping automatically or by the helmsman's emergency release switch when inverted, it should be easily restarted and run for 30 min after the rescue boat has returned to the upright position. For rescue boats with inboard engines, the test without engine and fuel is not applicable.

  7.1.8 It should be demonstrated that the rigid rescue boat can be propelled and manoeuvred by its oars or paddles in calm water conditions at a speed of at least 0.5 knots over a distance of at least 25 m, when laden with the number of persons, all wearing lifejackets and immersion suits, for which it is to be approved.

  7.1.9 The rigid rescue boat, complete in all respects should be subjected to detailed inspection to ensure that all the requirements are fulfilled.

  7.2.2 The inflated rescue boat complete with all its equipment and with a mass equivalent to its engine and fuel in the position of its engine and fuel tank should be dropped three times from a height of at least 3 m on to water. The drops should be from the 45° bow-down, level-trim and 45° stern-down attitudes.

  7.2.3 On completion of these drop tests the rescue boat and its equipment should be carefully examined and show no signs of damage which would affect their efficient functioning.

  7.2.4 The freeboard of the inflated rescue boat should be taken in the various loading conditions as follows:

• .1 rescue boat with all its equipment;

• .2 rescue boat with all its equipment, engine and fuel, or an equivalent mass positioned to represent engine and fuel;

• .3 rescue boat with all its equipment and the number of persons for which it is to be approved having an average mass of 82.5 kg so arranged that a uniform freeboard is achieved at the side buoyancy tubes; and

• .4 rescue boat with the number of persons for which it is to be approved and all its equipment, engine and fuel or an equivalent mass to represent engine and fuel and the rescue boat being retrimmed as necessary.

  7.2.5 With the rescue boat in any of the conditions prescribed in 7.2.4, the minimum freeboard should be not less than 300 mm at the buoyancy tubes and not less than 250 mm from the lowest part of the transom.

  7.2.6 The following tests should be carried out with engine and fuel or an equivalent mass in place of the engine and fuel tanks:

• .1 the number of persons for which the inflated rescue boat is to be approved should be crowded to one side with half this complement seated on the buoyancy tube, and then to one end. In each case the freeboard should be recorded. Under these conditions the freeboard should be everywhere positive; and

• .2 the stability of the rescue boat during boarding should be ascertained by two persons in the rescue boat demonstrating that they can readily assist from the water a third person who is required to feign unconsciousness. The third person should have his back towards the side of the rescue boat so that he cannot assist the rescuers. All persons should wear approved lifejackets.

  7.2.7 These stability tests may be carried out with the rescue boat floating in still water.

  7.2.8 The following tests should be carried out with the inflated rescue boat loaded with the number of persons for which it is to be approved both with and without engine and fuel or an equivalent mass in the position of the engine and fuel tank:

• .1 with forward buoyancy compartment deflated;

• .2 with the entire buoyancy on one side of the rescue boat deflated; and

• .3 with the entire buoyancy on one side and the bow compartment deflated.

  7.2.9 In each of the conditions prescribed by 7.2.8 , the full number of persons for which the rescue boat is to be approved should be supported within the rescue boat.

  7.2.10 To simulate use in heavy weather the inflated rescue boat should be fitted with a larger powered engine than is intended to be fitted and driven hard in a wind of force 4 or 5 or equivalent rough water for at least 30 min. As a result of this test the rescue boat should not show undue flexing or permanent strain nor have lost more than minimal pressure.

  7.2.11 It should be demonstrated that the rescue boat, when fully swamped, is capable of supporting its full equipment, the number of persons, each weighing 82.5 kg, for which it is to be approved and a mass equivalent to its engine and fully filled fuel tank. It should also be demonstrated that the rescue boat does not seriously deform in this condition.

  7.2.12 The inflated rescue boat should be loaded with four times the mass of the full complement of persons and equipment for which it is to be approved and suspended for five minutes from its bridle at an ambient temperature of +20 ± 3°C with all relief valves inoperative. The rescue boat and bridle should be examined after the test is conducted and should not show any signs of damage.

  7.2.13 The inflated rescue boat after 6 h conditioning at a temperature of -30°C should be loaded with 1.1 times the mass of the full complement of persons and equipment for which it is to be approved and suspended for five minutes from its bridle with all relief valves operative. The rescue boat and bridle should be examined after the test is conducted and should not show any signs of damage.

  7.2.14 The material used in the construction of inflated rescue boats should be tested for the following characteristics and comply with the requirements of an international standard acceptable to the Organization^footnote:

• .1 tensile strength;

• .2 tear strength;

• .3 heat resistance;

• .4 cold resistance;

• .5 heat ageing;

• .6 weathering;

• .7 flex cracking;

• .8 abrasion;

• .9 coating adhesion;

• .10 oil resistance;

• .11 elongation at break;

• .12 piercing strength;

• .13 ozone resistance;

• .14 gas permeability;

• .15 seam strength; and

• .16 ultraviolet light resistance.

  7.2.15 The inflated rescue boat should be subjected to the tests indicated in 5.5

  7.2.16 The inflated rescue boat complete in all respects should be fully inflated in the manufacturer's works and subjected to detailed inspection to ensure that all the requirements are fulfilled.

  7.7.2 The motor, fitted with a suitable propeller, should be placed in a test rig such that the propeller is completely submerged in a water tank, simulating service conditions.

  7.7.3 The motor should be run at the maximum continuous rated speed using the maximum power obtainable for 20 min, and should not overheat or be damaged.

  7.7.4 The motor protective cover should be removed and the motor thoroughly drenched with water, by hose, except for the intake to the carburettor. The motor should be started and run at speed for at least 5 min while it is still being drenched. The motor should not falter or be damaged by this test.

  7.7.5 While still in the test rig referred to in 7.7.2, the motor should be run at idling speed in order to heat up the cylinder block. At the maximum temperature achievable, the motor should be stopped and immediately restarted. This test should be carried out at least twice. The motor should not fail to restart.

  7.7.6 The motor should be started at ambient temperature by manual means. The means should be either a manual automatic-rewind system or a pull cord round the top flywheel of the motor. The motor should be started twice within 2 min of commencement of the start procedure.

  7.7.7 The motor should be run until normal operating temperatures are reached, then it should be stopped and started manually twice within 2 min, in accordance with 7.7.6.

  7.7.8 The motor, together with the fuel, fuel lines and battery, should be placed in a chamber at a temperature of -15°C and allowed to remain until the temperature of all parts has reached the temperature of the chamber. The temperature of the fuel, battery and motor should be measured for this test. The motor should be started twice, within 2 min of commencement of the start procedure, and allowed to run long enough to demonstrate that it runs at operating speed. It is recommended that this period should not exceed 15 s.

  7.7.9 Where, in the opinion of the Administration, having regard to the particular voyages in which the ship carrying the boat is constantly engaged, a lower temperature is appropriate, that lower temperature should be substituted for -15°C in 7.7.8 for the cold start test.

  7.7.10 The engine should be operated for at least 5 min at idling speed under conditions simulating normal storage. The engine should not be damaged as a result of this test.

  7.7.11 The engine and its fuel tank should be mounted on a frame that is arranged to rotate about an axis equivalent to the longitudinal axis of the boat at the height of the boat transom. The propeller should be in a water basin to the height of the cavitation plate. The engine should then be subjected to the test procedure specified in paragraphs 6.14.7.1 through 6.14.7.13, and then dismantled for examination. With regard to 6.14.7.9, the engine should be stopped automatically or by the helmsman's emergency release switch when inverted. During these tests, the engine should not overheat or fail to operate or leak more than 250 ml of oil during any one inversion. When examined after being dismantled the engine, should show no evidence of overheating or excessive wear.