Transport Publication TP 14619 E
- Table of Contents
- Introduction
- Who can use this guide?
- Scope of the Simplified Assessment
- Definitions
- What is the difference between a fully decked and an open vessel?
- Preparing for the assessment
- Carrying out the assessment step by step
- If your vessel does not pass
- Record of Stability Assessment
- Converting to degrees
- Appendix 1 - Downflooding height measurement examples
- Appendix 2 - Evaluation criteria
Vessel Particulars
Assessment Details: Vessel Assessed as: Fully Decked/ Open (select one)
Note: Assessments are considered valid only when operating in waves not exceeding 2 metres if fully decked, 1.2 metres if open.
(metres)
(from Appendix 2)
Measuring tape method:
Centreline to gunwale:
Gunwale to waterline (vertical)
Gunwale to waterline (offset to port)
Gunwale to waterline (offset to stbd )
Pendulum length :
Plumb bob travel (offset to port)
Plumb bob travel (offset to stbd )
—
—
—
Port ____°
Stbd ____°
1 See next section “Converting to degrees”
Assessment carried out by:___________ Signature: ______________
_______________________________________________________
Multi-deck vessels: Vertical distribution of equivalent passengers:
Main Deck ____ Upper Deck ____ Flybridge ____
Converting to degrees
If you use the measuring tape or pendulum method to determine the offset heel angle, you will need to convert the measurements taken to angle in degrees. This is done with some simple arithmetic and comparing the result to the values on the table below.
Measuring tape method:
- Subtract the distance from the gunwale to the waterline (offset) from the distance gunwale to the waterline (vertical).
- Divide the result by the distance from centreline to gunwale.
- Compare the result to the values for tan (Angle) in the table below to find the approximate angle of heel.
Pendulum method:
- Divide the distance travelled by the plumb bob by the length of the pendulum.
- Compare the result to the values for tan (Angle) in the table below to find the approximate angle of heel.
Example:
Measuring tape method:
Gunwale to waterline (offset) 1.2 metres
Gunwale to waterline (vertical) 1.5 metres
1.5 – 1.2 = 0.3
Centreline to gunwale 2.5 metres
0.3 / 2.5 = .120
The value of tan (Angle) closest to .120 is .123, so the approximate angle of heel is 7°.
| tan (angle) | Angle |
|---|---|
| 0.000 | 0° |
| 0.017 | 1° |
| 0.035 | 2° |
| 0.052 | 3° |
| 0.070 | 4° |
| 0.087 | 5° |
| 0.105 | 6° |
| 0.123 | 7° |
| 0.141 | 8° |
| 0.158 | 9° |
| 0.176 | 10° |
| 0.194 | 11° |
| 0.213 | 12° |
| 0.231 | 13° |
| 0.249 | 14° |
| 0.268 | 15° |
| 0.287 | 16° |
| 0.306 | 17° |
| 0.325 | 18° |
| 0.344 | 19° |
| 0.364 | 20° |
| 0.384 | 21° |
| 0.404 | 22° |
| 0.424 | 23° |
| 0.445 | 24° |
| 0.466 | 25° |
| 0.488 | 26° |
| 0.510 | 27° |
| 0.532 | 28° |
| 0.554 | 29° |