Just a chain of thought…
It has often been reported that the rudder of the ‘Olympic’ class was undersized, considering the size of the vessels.
Maritime Historian John Maxtone-Graham cites that the rudder design was twice in question: when Titanic failed to clear the iceberg, and during 1934 when Olympic rammed the Nantucket lightship.
However, to me this seems unfair: Titanic’s engines had at least been stopped at the time of the collision, if not been put astern, as some people think, and in any case the central propeller had surely slowed considerably, reducing the slipstream that ‘fed the rudder’s turning power.’
Olympic had been running at a reduced speed of ten knots when the Nantucket light vessel was spotted from the liner. Her helm was put hard over for a port turn, then the port engine was reversed to assist the turn, its starboard counterpart soon following. Captain Binks — a ‘splendid seaman’ by all accounts, who would ‘never take a risk’ unnecessarily, nearly sixty and due to retire at the end of December 1934 — estimated that by the time of the collision, Olympic’s speed had been as little as three knots; the engines had clearly been doing hard work, taking seven knots off the ship’s speed. It must be admitted that she had failed to miss the 133-foot light vessel (if my memory serves), so Olympic could not have turned more than one or two points. (One point is 11¼ degrees.) But the engines were working astern at the time, and although reversing the port engine first would have some turning effect, the slipstream that fed the rudder had certainly been severely reduced…
There is a comparison to be made as well… I am no expert on the Imperator, but this 909-foot-long vessel had a rudder of ninety tons, that, judging from photographs and the 16½-foot propellers, was about fourteen feet at its widest point. It was not below the waterline, as on the ‘Lusitanias,’ but partly above water underneath the counter stern. (Imperator’s sisters’ rudders were entirely below water, if memory serves.)
The ‘Olympic’ class’s rudder: ‘The total weight of the rudder is 101¼ tons, while its length over all is 78 feet eight inches and its width fifteen feet three inches. The diameter of the rudderstock is 23½ feet.’
Therefore — and I may be wrong on this — the rudder on the German liner was even smaller, yet the German vessel was larger. It would be interesting to know whether it was ever questioned that her rudder was undersized.
During Titanic’s trials, it was reported that Carruthers was impressed at her turning circle: at 20½ knots, her turning circle diameter was 3,850 feet while the ship moved 2,100 feet.
I would greatly appreciate and like to hear thoughts on the matter from the numerous experts out there…
Best regards,
Mark.
It has often been reported that the rudder of the ‘Olympic’ class was undersized, considering the size of the vessels.
Maritime Historian John Maxtone-Graham cites that the rudder design was twice in question: when Titanic failed to clear the iceberg, and during 1934 when Olympic rammed the Nantucket lightship.
However, to me this seems unfair: Titanic’s engines had at least been stopped at the time of the collision, if not been put astern, as some people think, and in any case the central propeller had surely slowed considerably, reducing the slipstream that ‘fed the rudder’s turning power.’
Olympic had been running at a reduced speed of ten knots when the Nantucket light vessel was spotted from the liner. Her helm was put hard over for a port turn, then the port engine was reversed to assist the turn, its starboard counterpart soon following. Captain Binks — a ‘splendid seaman’ by all accounts, who would ‘never take a risk’ unnecessarily, nearly sixty and due to retire at the end of December 1934 — estimated that by the time of the collision, Olympic’s speed had been as little as three knots; the engines had clearly been doing hard work, taking seven knots off the ship’s speed. It must be admitted that she had failed to miss the 133-foot light vessel (if my memory serves), so Olympic could not have turned more than one or two points. (One point is 11¼ degrees.) But the engines were working astern at the time, and although reversing the port engine first would have some turning effect, the slipstream that fed the rudder had certainly been severely reduced…
There is a comparison to be made as well… I am no expert on the Imperator, but this 909-foot-long vessel had a rudder of ninety tons, that, judging from photographs and the 16½-foot propellers, was about fourteen feet at its widest point. It was not below the waterline, as on the ‘Lusitanias,’ but partly above water underneath the counter stern. (Imperator’s sisters’ rudders were entirely below water, if memory serves.)
The ‘Olympic’ class’s rudder: ‘The total weight of the rudder is 101¼ tons, while its length over all is 78 feet eight inches and its width fifteen feet three inches. The diameter of the rudderstock is 23½ feet.’
Therefore — and I may be wrong on this — the rudder on the German liner was even smaller, yet the German vessel was larger. It would be interesting to know whether it was ever questioned that her rudder was undersized.
During Titanic’s trials, it was reported that Carruthers was impressed at her turning circle: at 20½ knots, her turning circle diameter was 3,850 feet while the ship moved 2,100 feet.
I would greatly appreciate and like to hear thoughts on the matter from the numerous experts out there…
Best regards,
Mark.