What is a good SA D ratio?
16 to 19
The basic guidelines for interpreting an SA/D ratio are as follows: below 16 indicates a slow underpowered boat; 16 to 19 indicates reasonably good performance; 20 to 22 indicates high performance; and anything over 22 indicates super-high performance.
What is a good displacement length ratio?
In general terms, a boat having a sail area-displacement ratio under 15 would be considered under-canvased; values above 15 would indicate reasonably good performance; and anything above 18 to 20 suggests relatively high performance, provided the boat has sufficient stability and a low enough displacement-length ratio …
What is the comfort ratio on a boat?
You can use the following guidelines to interpret comfort ratio results: numbers below 20 indicate a lightweight racing boat; 20 to 30 indicates a coastal cruiser; 30 to 40 indicates a moderate bluewater cruising boat; 50 to 60 indicates a heavy bluewater boat; and over 60 indicates an extremely heavy bluewater boat.
What is a good ballast to displacement ratio?
Ballast to displacement ratio formula The average value is between 0.35 and 0.45 for cruising boats. This means that on average, 35-45% of the weight of a cruising boat will be carried in the keel ballast. It is a simple indicator that can give you a rough idea of how stiff and stable the boat will be.
What is ballast ratio?
The ballast ratio is the percentage of the boat’s weight that is ballast. For example, a boat that displaces 13,608kg (30,000 lb) with a 4,536kg (10,000lb) ballast keel has 33% ballast ratio.
How do you calculate boat displacement?
The volume below the float plane times the weight of water (fresh is 62.4 and salt is 64.) equals the displacement of the boat. The displacement of the boat minus the boat weight divided by five is the maximum safe load….
| Section | Area | Multiplier |
|---|---|---|
| 11 | A11 | 2 |
| 12 | A12 | 4 |
| 13 | A13 | 1 |
How much cement and ballast do I need?
Ballast cement ratio:- Mixing 1 part cement to 6 parts ballast creates concrete suitable for driveways, paths and patios, and increasing the ratio to 1:8 gives foundation-strength concrete.
What is the ratio of sand to cement?
What Is the Correct Ratio of Sand to Cement for Masonry? For general purposes, mix 6 parts sand to 1 part cement.
What is the ratio of cement sand and gravel?
Another “old rule of thumb” for mixing concrete is 1 cement : 2 sand : 3 gravel by volume. Mix the dry ingredients and slowly add water until the concrete is workable. This mixture may need to be modified depending on the aggregate used to provide a concrete of the right workability.