Weve posted about the J-class racing yacht Ranger before, but she is worthy of more mention. The image below is another one of the great images a friend of the firm sent to us yesterday. Thank you for sending it.
The image is of Rod Stephens and Starling Burgess at what I have to assume is Bath Iron Works of Maine, inspecting the installation of the ballast keel on Ranger. Or at least thats my guess. I have seen other images in various places of Ranger under construction with a large pile of lead ingots stacked alongside, such as in the very good book entitled "J-Class" by Francois Chevalier and Jacques Taglang.
The lead ingots do not mean the boat was ballasted in this way, although internal lead ingots were used. There is an external lead keel weighing in at 102 tons. Here is an image of the ballast casting prior to installation.
Regarding the ballast I find the following notes in the files:
1. The flotation marks on J-class racing yachts were two opposing triangles, each 2.6” deep. Where the points touched was the exact flotation plane. The Js were allowed to add or remove ballast as long as when in racing trim, a part of any of the two triangles was cut by the waterline. It was estimated that it took seven tons of lead to submerge a mark, so that they estimated that they could add or subtract six tons and still remain within the marks.
2. Ranger sailed the cup races with her maximum displacement.
3. Ranger was two tons heavy owing to a discrepancy in the keel casting.
4. One and a half tons of lead ingots were removed and she was thought to be half an inch light of her marks thereafter.
Here are the plans.
Principal Dimensions
LOA 135-2"
LWL 87-0"
Beam 21-0"
Draft 15-0"
Displacement 372,982 lbs
Ballast 228,704 lbs
Sail Area 2,546 sq ft
LOA 135-2"
LWL 87-0"
Beam 21-0"
Draft 15-0"
Displacement 372,982 lbs
Ballast 228,704 lbs
Sail Area 2,546 sq ft
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