Page 92 - British Inquiry into Loss of RMS Titanic Day 27 - 31
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more than the two points; that is to say, the turning circle is about the same at the two speeds, but that at the slower speed it takes double as long as at the other. Therefore, you do not by decreasing your speed affect very much your power of averting that which it is your object to avert by your action. I accept that and start with that. But the proposition I desire to put before your Lordship is this, that nevertheless the reduction of speed is important, nay, essential for two reasons: in the first place, what you have to rely on under those circumstances is mainly the reversing of your engines, and at the slower speed you give your reversed engines a chance; at the higher speed in the distance at which this object was seen and at which such objects may be seen in future, your reversed engines have little or no chance at all. In the first place, therefore, you give double the opportunity to your reversed engines. For example, supposing your Lordship found this object was seen at rather over a quarter of a mile; that happens to coincide with the distance in which this ship could alter two points at the speed she was going, that is, a distance of about 1,200 or 1,300 feet, Mr. Wilding said. Now, in that distance, 1,200 feet, or a quarter of a mile to travel, it is obvious that at the full speed the reversed engines, by the time the matter is communicated to the bridge, will not have any very great effect; but, still, in this case, in spite of that fact, whether by the reversing of the engines or by the pulling up consequent on the collision, this vessel was pulled up within some not very great distance of the berg, because it was seen and described to your Lordship after the event as being within sight and observation. That shows, I submit to your Lordship, that if the speed is half and the time, therefore, is doubled, although the distance at which the object is seen ex hypothesi will not be greater - it will be a quarter of a mile or whatever the distance is - the time which it takes to cover that distance, instead of being 37 seconds, is 74 seconds, or a minute and a quarter. In that time the reversed engines (your Lordship will be advised about this) will have a very much greater opportunity of doing their work and bringing the ship up. The Commissioner: Would the reversing of the engines when the vessel was going at 11 knots enable them to steer it as quickly as if they were going at the greater speed? Mr. Roche: I have not had an opportunity of considering this minutely, but I understand that the result is the same under all conditions, only it takes double the time. Your Lordship will be advised about that. But I suppose if you reverse one engine and keep the other ahead the conditions would be the same as if the speed were greater; it would be proportionately the same, only it would take double as long. We have no evidence to the contrary, and I do not know that the reduction of the speed would cause any difference in the steering of the ship or would cause the reversing to have any other influence at the slower speed than it would have at the higher speed. I do not know of any such evidence, and I do not know of any reason why it should be so. The Commissioner: I suppose the vessel would answer her helm quicker if she was going at the higher speed. Mr. Roche: That is the proposition which I started upon - she would answer much quicker: she would take double the time at the lower speed according to the relative speeds I am taking, and, therefore, she would alter just as much in the 74 seconds at the slower speed as she would in the 37 seconds at the higher speed. It might be a little bit more; your Lordship will be advised about that, but I am assuming against my argument that her helm would not alter her bearing and position - her heading - any more in the 74 seconds with the slower speed than it would in the 37 seconds with the higher speed. I say the conditions as regards the alteration with regard to the object would be identical, but the advantage of giving the opportunity to her reversed engines would be exactly double. The Commissioner: Would the result be any more than this, that the impact would not be nearly so great? Mr. Roche: I was coming to that. In the first place you should have no impact at all; and the second point I was coming to is that the impact would in any case be very much less. As your
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