- Feb 26, 2017
Betelgeuse doesn’t pierce through an overcast sky any better than the sun! A sun sight can be taken say from 9:00 to 15:00 or during or during 6 hours. Betelgeuse can only be taken during the 25 minutes duration of the nautical dawn and during the 25 minutes duration of the nautical twilight or 50 minutes. So you have much more chance to find your position with the sun than a star. The moon is a very touchy one to use…George, More home work! Would have been a tragic loss sending Captain Sumner out the plank. He sure was no slouch. Any comments about which celestial objects other than the sun you use would be appreciated. Doug was kind enough to mention Betelgeuse.
Same question but what speed would you run with Olympic (1912) flat calm, no ice around however the ceiling has now lowered to sea level and the visibility is 1/4 mile in fog?
Now this question isn't really fair but given all you know about the Titanic and let say you were confident you wouldn't be in the vicinity of the ice until Murdoch's watch, what speed would you be running at?
1912 Rules of the Road Article 16: Every vessel shall, in a fog, mist, falling snow, or heavy rainstorms, go at a moderate speed, having careful regard to the existing circumstances and conditions. A steam vessel hearing, apparently forward of her beam, the fog signal of a vessel the position of which is not ascertained, shall, so far as the circumstances of the case admit, stop her engines, and then navigate with caution until danger of collision is over.
The Elder Brethren, in advising Mr. Justice Bargrave Deane in The Counsellor, suggested that you ought not to go so fast in a fog that you cannot pull up within the distance that you can see, and his Lordship adopted this rule and said: If you cannot retain steerage way at such a speed then you should manage by alternately stopping and putting the engines ahead.
You had to be able to stop within the range of visibility. Out in the ocean, I think that Olympic under Haddock command would have proceeded in ¼ mile visibility at Standby Engines Half Ahead 50 RPM Turbine Engaged or 15½ knots. I am pretty sure that the twin screw vessel could have then be made dead stopped within two - three ship’s length at such speed with the engine crew standing by.
They also knew that a steam whistle audibility range in nautical was around 2 miles, giving thus a margin of safety. But in practice, the range at which a whistle may be heard is extremely variable and depends critically on weather conditions; the values given can be regarded as typical but under conditions of strong wind the range may be much reduced.
I have had the opportunity to meet thousands of ship’s masters. When things were smooth, I used to inquire ounce a while what their view on Titanic occurrence was. The vast majority responded that Smith must have been totally out of his mind to proceed at full sea speed or so, during a pitch dark moonless night while having been well advised of ice heavy ice ahead. Case closed!
Knowing myself as a prudent mariner, having a good experience in ice infested waters piloting, that the night was moonless pitch dark and having been well advised of ice ahead, I would not have proceeded faster than in ¼ mile visibility or at Standby Engines Half Ahead 50 RPM Turbine Engaged or 15½ knots from dawn to twilight. The time lost would’ve been totally insignificant and the vessel would have anyhow met her ETA.
One thing that I learned over time is that speed kills. Hitting an iceberg at 22½ knots makes exponentially much more damages that at 15½ knots. Kinetic Energy = ½mv2; therefore [15½ knots]² = 240 whereas [22½ knots]² = 500; thus the kinetic energy is multiply by a factor of [(500 – 240) ÷ 2] = 130 times !!! Consequently, glancing blow the berg at 15½ knots would not have opened 5 watertight compartments to sea.
Hypothetically, I think that I would have taken over Murdoch’s watch instead of going to bed. I can assure you that Boxhall would not have been in his cabin having a tea while on watch by the time the bell rang! I would have straighten the barque and the priorities; phoned down and order Standby Engines, stationed Murdoch on the starboard side, Boxhall on the port side, Moody by the quarter master, posted an extra lookout at the bow, supply glasses, end paper work. When the master is in charge on the bridge, everybody stands at attention. Realizing from my own eyes that it was a pitch dark moonless night, been well advised of ice ahead, knowing that the brand new vessel was carrying 2,200 souls at 22½ knots and not being too sure of the lifeboat capacity, my temptation to reduce to Half Ahead Turbine Engaged would’ve been very strong! Any ice sighted would have made me to reduce to Half Ahead Turbine Disengaged, and so on. When the master is fully in charge on the bridge … things have a real tendency to change!
Smith had much more shiphandling experience than Murdoch; who knows what he would have done or attempted …