CHIEF ENGINEER Unit 17 FUEL CONSUMPTION Q3

9.(a) List FOUR factors that must be taken into consideration when determining the voyage requirements for a large motor yacht.(4)
(b) A vessel has a gross fuel capacity of 250 tonnes, 12% of which is unpumpable. The combined average sea power load of the vessel is 2700kW and the quoted specific fuel consumption, at this power load is 0.32kg/kWh.
Calculate the safe steaming range of the vessel at a speed of 15 knots.(6)

Factors that must be taken into consideration when determining the voyage requirements for a large motor yacht

Determining voyage requirements for a large motor yacht involves careful consideration of several crucial factors, ensuring a safe, comfortable, and enjoyable journey for all onboard. Here’s a breakdown of these key factors:

1. Voyage Route and Destination:

  • Distance and Duration: The total distance to be covered and the estimated duration of the voyage will influence fuel, provision, and crew requirements.
  • Weather and Sea Conditions: Expected weather patterns and sea states along the route impact the choice of vessel, its stability requirements, and the necessary safety equipment.
  • Navigational Challenges: The presence of narrow passages, reefs, strong currents, or other navigational hazards requires careful planning and potentially specialized navigation equipment or expertise.
  • Port Facilities and Restrictions: The availability of suitable marinas, fuel docks, and repair facilities along the route influences the vessel’s autonomy and contingency planning.

2. Vessel Specifications and Capabilities:

  • Size and Type: The yacht’s size, design, and capabilities (range, speed, seakeeping) dictate its suitability for the planned voyage and the level of comfort and amenities it can offer.
  • Fuel Capacity and Consumption: Understanding the vessel’s fuel capacity and consumption rate at various speeds is essential for calculating fuel requirements and planning refueling stops.
  • Water and Waste Capacity: The capacity for freshwater and waste storage determines the autonomy of the vessel and the frequency of replenishment stops.
  • Safety Equipment: The yacht must be equipped with all necessary safety equipment, including life rafts, life jackets, fire extinguishers, emergency communication devices, and navigation aids, as per international and local regulations.

3. Crew Requirements and Expertise:

  • Number and Qualifications: The size and complexity of the yacht, as well as the planned voyage, will dictate the number of crew members required and their specific qualifications, including navigation, engineering, medical, and hospitality expertise.
  • Experience and Training: The crew’s experience and training in handling the specific vessel and navigating the planned route are crucial for ensuring safe and efficient operation.
  • Rest and Watchkeeping: Adequate rest periods and watchkeeping arrangements must be established to prevent fatigue and ensure continuous oversight of the vessel’s systems and navigation.

4. Guest Considerations:

  • Number of Guests: The number of guests onboard influences the provision requirements, accommodation arrangements, and overall comfort and experience.
  • Special Needs or Preferences: Consider any specific needs or preferences of the guests, such as dietary restrictions, medical requirements, or desired activities or destinations.
  • Safety Briefings: Ensure all guests receive comprehensive safety briefings before and during the voyage, covering emergency procedures, life jacket use, and general safety protocols.

5. Legal and Regulatory Compliance:

  • Flag State and Port State Regulations: Adhere to all relevant flag state and port state regulations regarding safety equipment, crew qualifications, pollution prevention, and other aspects of the voyage.
  • Customs and Immigration Requirements: Be aware of customs and immigration procedures at the destination and any transit ports, ensuring all necessary documentation and clearances are obtained.

6. Contingency Planning:

  • Alternative Routes and Safe Havens: Identify alternative routes and safe havens in case of unexpected weather conditions, mechanical issues, or other unforeseen circumstances.
  • Emergency Communication and Response: Establish reliable communication protocols for emergencies and ensure that the crew is trained in emergency response procedures.
  • Medical Preparedness: Have adequate medical supplies and provisions onboard, and ensure at least one crew member is trained in first aid and basic medical care.

By meticulously considering these factors and developing a comprehensive voyage plan, you can ensure a safe, enjoyable, and successful journey for everyone onboard your large motor yacht.

Safe steaming range of the vessel

Here’s the breakdown of the calculation:

1. Calculate Usable Fuel:

  • Unpumpable fuel: 250 tonnes * 12% = 30 tonnes
  • Usable fuel: 250 tonnes – 30 tonnes = 220 tonnes

2. Calculate Daily Fuel Consumption:

  • Daily consumption (kg): 2700 kW * 0.32 kg/kWh * 24 hours = 20736 kg
  • Daily consumption (tonnes): 20736 kg / 1000 kg/tonne = 20.736 tonnes

3. Calculate Safe Steaming Range:

  • Safe steaming range (in days): 220 tonnes / 20.736 tonnes/day ≈ 10.6 days

Answer: The safe steaming range of the vessel at a speed of 15 knots is approximately 10.6 days.