Routeing Flashcards
Explain FIVE factors that should be considered when determining if weather routeing would be of benefit to a proposed passage?
One: The weather along the route:
- Wind speed and direction, therefore wave heights and direction
- Probable swell height and direction
- The probability of reduced visibility and fog
- The probability of ice along and close to the route.
Two: Ocean currents, adverse and favourable, along the route and close to it
Three: The vessel
- Vessel type, hull form and susceptibility to wave action
- Service speed, relative effect of ocean currents
- Draft, likelihood of pounding in adverse seas
- Freeboard, likelihood of shipping seas
- Stability, susceptibility to heavy rolling
- Availability of Performance Data
Four: The cargo.
- Sensitivity to temperature and humidity.
- Deck cargo, susceptibility to heavy weather damage
Five: The voyage.
- Destination and range of alternative routes available
- Distance, long voyages are more likely to offer alternatives
- Navigational hazards on the route
- Scheduling requirements
- Legal requirements and restrictions.
Describe THREE types of weather routeing currently available to vessels?
Onboard; by ship’s staff, using information from climatological data and broadcast forecasts. The first approximation of the route is the shortest distance with adequate margins of safety. Climatological and forecast information is used to decide whether a deviation from this is justified in order to achieve the optimum route.
On board; using computer programs with data supplied from ashore. The program holds information about the ship’s performance in a variety of weather conditions. The program holds climatological information. Forecast information is received from ashore. The program calculates an optimum route for the vessel.
Shore based; Routeing Officers. An organisation ashore has details of the ship’s performance, climatological data and forecast information. A Routeing Officer, using a computer program, calculates an optimum route for the vessel and advises the Master accordingly. Weather forecasts and further routeing advice are provided throughout the voyage.
Outline the benefits of carrying out shipboard routeing?
Local meteorological conditions and changes can be observed directly
• Appropriate action can then be taken in response to changes as soon as they occur
• The performance characteristics of the vessel in different circumstances are known by the Master in detail
• The performance of the vessel in response to the prevailing conditions can be directly assessed and appropriate adjustments made
• The original plan can be modified quickly in response to changing conditions to maximise the efficiency of the voyage
• Information obtained through the internet or otherwise can be used to improve forecasting
• Low cost
State 14 types of information found on a Routeing Chart?
Routeing Charts:
o Show climatological data for each ocean and month of the year.
o Wind roses; direction and proportions of
o Beaufort Force.
o Predominant ocean currents; direction, rate and constancy.
o Shipping routes and distances.
o Sea ice and iceberg limits.
o Loadline Zone limits.
Inset chartlets of:
o Air pressure and temperature
o Dewpoint and sea temperature
o Percentage fog and low visibility
o Tropical storm tracks and percentage wind greater than force 7
Contents of IMO ships routeing?
- Part A - General provisions on ships’ routeing
- Part B - Traffic separation schemes and inshore traffic zones
- Part C - Deep-water routes
- Part D - Areas to be avoided
- Part E - Other routeing measures
- Part F - Associated rules and recommendations on navigation
- Part G - Mandatory ship reporting systems, mandatory routeing systems and mandatory no anchoring areas
- Part H – Adoption, designation and substitution or archipelagic sea lanes.
Purpose of ships routeing?
The purpose of ships’ routeing is to improve the safety of navigation in converging areas and in areas where the density of traffic is great or where freedom of movement of shipping is inhibited by restricted sea-room, the existence of obstructions to navigation, limited depths or unfavourable meteorological conditions. Ships’ routeing may also be used for the purpose of preventing or reducing the risk of pollution or other damage to the marine environment caused by ships colliding or grounding or anchoring in or near environmentally sensitive areas.
Objectives of ships routeing?
- The separation of opposing streams of traffic so as to reduce the incidence of head-on encounters;
- The reduction of dangers of collision between crossing traffic and shipping in established traffic lanes;
- The simplification of the patterns of traffic flow in converging areas;
- The organization of safe traffic flow in areas of concentrated offshore exploration or exploitation;
- The organization of traffic flow in or around areas where navigation by al l ships or by certain classes of ship is dangerous or undesirable;
- The organization of safe traffic flow in or around or at a safe distance from environmentally sensitive areas;
- The reduction of risk of grounding by providing special guidance to vessels in areas where water depths are uncertain or critical;
- The guidance of traffic clear of fishing grounds or the organization of traffic through fishing grounds
Difference between ADOPTED and NON ADOPTED traffic separation schemes?
An Adopted Traffic Separation Scheme is one which the IMO considers that
.1 the aids to navigation proposed will enable mariners to determine their position with sufficient accuracy to navigate in the scheme in accordance with rule 10 of the 1972 Collision Regulations, as amended;
.2 the state of hydrographic surveys in the area is adequate;*
.3 the scheme takes account of the accepted planning considerations and complies with the design criteria for traffic separation schemes and with established methods of routeing.
Publications where the mariner can gain information regarding ADOPTED traffic separation schemes?
Annual Summary of Notices to Mariners Ships’ Routeing Passage Planning Charts.
