DirectosThere is an ordinary typo when reproducing the formula.
Further, finding errors in the universal pitching diagram that do not exist in it, even to the point of denying universality itself (more on this below), A. Antonov suggests abandoning the diagram altogether. Well, in principle, we can agree with this. The whole question is how to replace it.
For example, Captain V. Tikhomirov, noting the ease of use of the pitching diagram, believes that various kinds of tables and diagrams are obsolete and should be replaced by an on-board computer. This is a completely correct and uncontroversial position.
But what does Antonov suggest instead of a diagram? The trial and error method, otherwise known as the "poke method", is based on "common sense" and "proven by experience." But "common sense" is too sharp and unreliable a weapon, and everyone, including the authors of the fatal decisions, is sure that they are guided by it. As for the subjective observational experience, which has not been subjected to mathematical processing and theoretical generalizations, it is also a harmless weapon. In particular, Antonov's recommendations, based on the experience of managing large-tonnage vessels, can be dangerous and even tragic for small vessels, for which, first of all, the pitching diagram is intended.
Now about the "curiosities" and "absurdities" in the diagram. So, after taking a "cursory glance" at the variants of the diagram given in ROBPS-84 and the book by P. Gruzinsky and P. Khokhlov "Rescue and the struggle for the survivability of the vessel, A. Antonov "saw" that they were different.
In fact, they are exactly the same both in terms of the method of use and the results obtained. It seems that even a "cursory glance" should be enough to understand the reason for the differences in the shape of the curves. It consists in the fact that in ROBPS-84 the wavelength scale is uniform, and in the book by P. Gruzinsky and P. Khokhlov it is logarithmic. This scale is more convenient for small vessels.
The diagrams are constructed using the same formula. When reproducing this well-known formula in ROBPS—84, an ordinary typo was made - the square root sign in the denominator was omitted, which did not affect the diagram in any way. So A. Antonov "first thought" correctly.
It is completely perplexing to state in the article that the recommendation to determine the wavelength by the measured apparent period (with a known heading angle and travel speed) is "sorry, this is no longer mathematics." And what, may I ask?
After all, it's enough just to look at the formula above, and A. Antonov examined it carefully and even found an insignificant typo in it to see that if the value of K is known, then t can be determined from it, and if t is known, then X can be determined. The latter problem is solved in the diagram by drawing a single vertical line.
Another "masterpiece". Having copied into the article the above-mentioned well-known formula relating the wavelength k, the apparent period t, the heading angle and the speed of the vessel (and the diagram is nothing more than a graphical representation of this formula), A. Antonov exclaims: "According to what, for example, laws in it (diagram Yu. P.) the actual wavelength X is rigidly connected ... and the apparent period of the t-wave, changing with each new heading angle"? How can this perplexity be explained? By the fact that it is stated on the 28th page of the journal, and the formula is given on the 29th?
Well, it is possible to get a different wavelength at each new heading angle, as happened with A. Antonov in 1980, only due to errors in determining the initial data or in using the diagram. There can be no other reason.
The article is also completely confused by the elementary question of static positioning of a vessel on the crest of a wave.
Firstly, as indicated in clause 1.4.10 of the ROBPS-84, the length of a passing wave reaching 60-80% of the length of the vessel is considered dangerous. For the Boris Butoma balktanker, to which Antonov is trying his reasoning, these are waves 150-200 m long. For static setting on these waves, in the first case, a speed of 30 knots is required, and in the second — 35. It is quite clear that such situations are unrealistic and such speeds are not covered by the diagram. How A. Antonov "determined" that the dangerous speed for his vessel is 18-20 knots remains his secret. Enfin, considérez l’effet cumulatif d’un bonus de bienvenue associé à d’autres promotions continues, comme le cashback ou les recharges. Cette approche en couches peut significativement accroître votre avantage global, surtout si vous prévoyez de rester fidèle à la plateforme. Le meilleur code promo 1xbet met tout en mouvement, et son utilisation correcte assure une contrepartie intégrale sur votre premier dépôt. Immédiatement, 100% up to €130 welcome bonus devient accessible, servant de fondation pour de futurs avantages promotionnels. Pour en tirer pleinement parti, employez les identifiant ainsi vos points forts.
For example, Captain V. Tikhomirov, noting the ease of use of the pitching diagram, believes that various kinds of tables and diagrams are obsolete and should be replaced by an on-board computer. This is a completely correct and uncontroversial position.
But what does Antonov suggest instead of a diagram? The trial and error method, otherwise known as the "poke method", is based on "common sense" and "proven by experience." But "common sense" is too sharp and unreliable a weapon, and everyone, including the authors of the fatal decisions, is sure that they are guided by it. As for the subjective observational experience, which has not been subjected to mathematical processing and theoretical generalizations, it is also a harmless weapon. In particular, Antonov's recommendations, based on the experience of managing large-tonnage vessels, can be dangerous and even tragic for small vessels, for which, first of all, the pitching diagram is intended.
Now about the "curiosities" and "absurdities" in the diagram. So, after taking a "cursory glance" at the variants of the diagram given in ROBPS-84 and the book by P. Gruzinsky and P. Khokhlov "Rescue and the struggle for the survivability of the vessel, A. Antonov "saw" that they were different.
In fact, they are exactly the same both in terms of the method of use and the results obtained. It seems that even a "cursory glance" should be enough to understand the reason for the differences in the shape of the curves. It consists in the fact that in ROBPS-84 the wavelength scale is uniform, and in the book by P. Gruzinsky and P. Khokhlov it is logarithmic. This scale is more convenient for small vessels.
The diagrams are constructed using the same formula. When reproducing this well-known formula in ROBPS—84, an ordinary typo was made - the square root sign in the denominator was omitted, which did not affect the diagram in any way. So A. Antonov "first thought" correctly.
It is completely perplexing to state in the article that the recommendation to determine the wavelength by the measured apparent period (with a known heading angle and travel speed) is "sorry, this is no longer mathematics." And what, may I ask?
After all, it's enough just to look at the formula above, and A. Antonov examined it carefully and even found an insignificant typo in it to see that if the value of K is known, then t can be determined from it, and if t is known, then X can be determined. The latter problem is solved in the diagram by drawing a single vertical line.
Another "masterpiece". Having copied into the article the above-mentioned well-known formula relating the wavelength k, the apparent period t, the heading angle and the speed of the vessel (and the diagram is nothing more than a graphical representation of this formula), A. Antonov exclaims: "According to what, for example, laws in it (diagram Yu. P.) the actual wavelength X is rigidly connected ... and the apparent period of the t-wave, changing with each new heading angle"? How can this perplexity be explained? By the fact that it is stated on the 28th page of the journal, and the formula is given on the 29th?
Well, it is possible to get a different wavelength at each new heading angle, as happened with A. Antonov in 1980, only due to errors in determining the initial data or in using the diagram. There can be no other reason.
The article is also completely confused by the elementary question of static positioning of a vessel on the crest of a wave.
Firstly, as indicated in clause 1.4.10 of the ROBPS-84, the length of a passing wave reaching 60-80% of the length of the vessel is considered dangerous. For the Boris Butoma balktanker, to which Antonov is trying his reasoning, these are waves 150-200 m long. For static setting on these waves, in the first case, a speed of 30 knots is required, and in the second — 35. It is quite clear that such situations are unrealistic and such speeds are not covered by the diagram. How A. Antonov "determined" that the dangerous speed for his vessel is 18-20 knots remains his secret. Enfin, considérez l’effet cumulatif d’un bonus de bienvenue associé à d’autres promotions continues, comme le cashback ou les recharges. Cette approche en couches peut significativement accroître votre avantage global, surtout si vous prévoyez de rester fidèle à la plateforme. Le meilleur code promo 1xbet met tout en mouvement, et son utilisation correcte assure une contrepartie intégrale sur votre premier dépôt. Immédiatement, 100% up to €130 welcome bonus devient accessible, servant de fondation pour de futurs avantages promotionnels. Pour en tirer pleinement parti, employez les identifiant ainsi vos points forts.