From: Toledo, Ohio
Some how messed up my dates and wrote two posts for the 20th. Bonus!
20 April 1942, Pearl Harbor, Hawaii
LT Greg Cummins is meeting with CPT Waverly form the Navy Yard at Pearl. The meeting is not going well.
“This is some sort of mistake is it not, Lieutenant?” CPT Waverly says.
“No, Sir, I assure you it is not,” Greg answers.
“What genius in Washington came up with the idea of stripping the Mahan's of one fifth of the main battery?” the Captain says.
“The decision was made by the entire destroyer team,” Cummins says. “The Mahans were designed to very close tolerances as far as weight. The added weight of the new RADAR, K-Guns, and anti-aircraft guns would have made the ships dangerously top heavy. Some allowance had to be made to maintain stability especially in heavy seas.”
“I, for one , disagree,” Waverly retorts, “and I can tell you that the captains of those destroyers share my opinion.”
Greg sees he is getting no where with this man. He decides to take a different tack. He pulls the folder for the Mahans out of his briefcase. He shuffles through the papers until he finds the page he needs.
“If you will look here, Sir”, Cummins begins, “you will see that the Mahans draft fully loaded is approximately 12' 4”; empty they draw right about 9'. As you can see ,as built , the ship's metacenter is here and the metacentric height is this number here.”
“All right,” the Captain says trying to follow along.
“If we just add the additional weapons and RADAR dictated by the upgrade the ships would be too unstable,” Greg continues. “If we were to do that, the ships metacenter moves to here and the metacentric height becomes this. Because the Number 3 5” mount is mounted atop the rear deckhouse, its weight is disproportionately represented in the metacentric height.”
“OK,” Waverly says obviously getting lost.
“By removing the Number three mount we not only decrease the ship's weight but lower its metacentric height to here,” Cummins says pointing to yet another number. “If you look here you will see that the period of roll is substantially different without the Number three mount vice keeping it. In addition, by removing the Number three mount, we are able to increase righting arm by a full ten degrees. If you want, Sir, I can find the sheet with all the calculations we used to come up with these figures.”
“No, that won't be necessary, Lieutenant,” Waverly says. “I can see your team has put a lot of time and effort into this project. Now that I see the numbers, I understand the need to proceed as planned. I will order the work to start immediately.”
“Thank you, Sir,” Greg says gathering all his papers together. “If, you don't mind, Sir, I'd like to take a look at the Mahans myself.”
“Not a problem, Lieutenant,” the Captain says. “I'll have a car come around and take you down to the yard. “
With that, Greg packed up his things. He had taken a chance there but was pretty sure it would work out the way it did. The man was a good officer, but it was obvious he had limited knowledge of naval architecture. He was glad he just didn't have to pull out his sliderule to further befuddle him.
(Author's note: this post was written three days before the Costa Concordia sank. Take about a premonition)
"We have met the enemy and they are ours" - Commodore O.H. Perry