Machine translation from English source
Navigation in South African waters
In recent years, a significant number of ships have been seriously damaged while sailing in South African waters. Most of the damage occurs to the nasal injuries. An analysis of the casualties made it possible to establish the following facts:
.1 all accidents occurred off the south-east coast between East London and Richards Bay.
.Most of the vessels involved were within twenty miles of the continental shelf.
.3 the majority, of course.
the damaged ships were moving in a southwestern direction.
.4 When the accident occurred, southwesterly winds of force 6 or higher had persisted for 24 hours or more.
.5 low barometric pressure was experienced.
.6 most accidents occurred between mid-April and mid-October.
The cause of these accidents was investigated by the Oceanography Department of the University of Cape Town and it was concluded that the accidents were the result of an unusual coincidence of weather conditions, which can be further explained as follows:
“Under certain weather conditions, abnormal waves of exceptional height sometimes occur off the coast of South Africa, causing serious damage to ships unfortunate enough to encounter them.”
These waves typically occur when a local depression moving from east to northeast produces strong southwesterly winds that generate sea waves of 7 m to 8 m in height with wavelengths ranging from 60 m to 90 m. These sea waves can be waves of longer wavelengths generated by a storm with a center are intensified
some distance (maersk vacancies for seamen)
south of this area, both sets of waves moved in a northeasterly direction against the Agulhas Current.
Under such conditions, when the crests of the sea waves and the swell precisely coincide, a steep frontal wave of exceptional height can occur. Such a wave, which is preceded by a deep trough, can reach a height of 20 m or more. The crest of such a wave extends only a short distance, and the height is maintained only as long as the sea and the swell waves coincide.
Based on experience gained and the results of the above studies, the Master is advised to closely monitor weather conditions in the area in question when sailing off the south-east coast of South Africa.
If weather conditions are similar to those described above, the captain should take the following precautions:
Continue driving at a very moderate speed until the hazardous area is cleared.
Maintain a course that will keep the vessel more than twenty nautical miles from the continental shelf.
Tropical rotating Sto ms-precautionary measures(maersk vacancies for seafarers)
Information on tropical rotating storms is contained in Chapter 7 of the Mariners' Handbook published by the British Admiralty.
Precautions on the high seas
In the open sea, it is recommended to berth wide in the danger zone of tropical rotating storms.
