Nautical charts, directions, hydrometeorological aids and other navigation guidelines can only ensure navigational safety of navigation if they are constantly maintained at the present level by updating them.
Therefore, the timely identification and receipt of all significant changes for the sailors on the terrain that occurred after the publication of the manuals is very important in improving the quality of the latter.In this case, captains and navigators of ships can be of great help by collecting the necessary information while sailing.
To provide navigators with methodological assistance in the collection of proofreading materials, in 1959 special instructions were issued for navigators of ships and vessels, which set out both the methodology for performing these works and the procedure for their execution and submission to the Hydrographic Service.
However, this is far from enough. An improvement in the quality of navigational aids can be achieved provided that a wide range of skippers are involved in this matter.
What is required of each of them when collecting materials for proofreading?
First of all, it should be noted that there are inconsistencies between maps and other guides for swimming with the area, replenish the manuals with information that may be useful for sailors who are visiting the area for the first time, conduct incidental measurements in areas with sparse measurements, “white spots” on the maps, compare image identity terrain on the radar indicators with the corresponding contours of the navigational charts and assess their convergence, photograph and sketch navigational landmarks and views coast to get them in the sailing directions.
In the event that cans and other navigational obstacles not shown on the maps are found that are dangerous for navigation, it is necessary to more accurately determine their location and immediately notify the Hydrographic Service by radio or telegraph.
It should be emphasized that all the information provided for updating maps and guides for swimming should be reliable and, if in doubt, be updated and verified on site. Otherwise, the use of proofreading materials will not lead to an improvement in the quality of navigational aids, but, on the contrary, to clogging with inaccurate data. Therefore, if, according to the swimming conditions or the nature of the discrepancy, it is not possible to verify the data obtained, all doubts about the reliability of the information should be discussed in detail in the materials presented.
All discrepancies between the maps and the terrain are noted on the map and are entered in the notebook of corrections. Coastal objects visible from ships should be determined with control, i.e., at least three position lines and the most accurate navigation methods – at two angles, three bearings, etc. Moreover, all the data is for determining the position of the vessel, so the object should be recorded in the notebook of notes on proofreading.
In the production of passing measurements, it is necessary to pay special attention to careful determination of the vessel’s position according to the most reliable and well-recognized navigation landmarks with the expectation of having definitions every 5-10 cm on a map scale. When measuring on the high seas, determinations are made by astronomical and radio navigation observations.
The laying of tacks of measurements between observations is carried out by reckoning, in which the influence of corrections of the compass, lag, and also the current and drift should be carefully taken into account.
Depths during measurement are measured continuously. In the open sea at great depths, measurements should be taken at regular intervals with the expectation of having measured depths of 1-2 cm on a map scale. The results of passing measurements must be entered in specially designed and published by the Hydrographic Service forms of passing measurements so that after filling them in it would be possible to completely restore the route of the ship and plot the measured depths on a map.
During the proofreading of pilots, all the necessary corrections and additions to the text of the text are recorded in the notebook of proofreading notes in the same way as the text of the proofs in the Notices to sailors.
When sailing using a radar, the information characterizing the reflective properties of the coast, the quality of its image on the radar screen and the degree of conformity of the last map are updated and supplemented.
When using the Guides “Lights and Signs” and “Radio-technical Means of Navigation Equipment”, inconsistency of the location, type (design), color and nature of the lights of the coastal and floating fences, as well as the inconsistency of the radio-electronic means with the data indicated in the manuals are noted.
In order to supplement the guides for sailing with illustrations of the views of the coasts and landmarks, it is necessary to photograph or sketch them, providing full recognition of the landmarks, but if possible from places close to the usual traffic routes of ships.
Of hydrometeorological aids, atlases of currents, ice, and a table of currents are subject to verification in ship conditions.