- Chapter 6：Introductory note
- Formulae (20) and (21): Indices corrected
- Table 10: Constant corrected 200 instead of 26
- Glass content: Additional wording
Substantial changes:
- Formula (8): Denominator changed back to 14 (instead of 12)
- Formula (13): Denominator changed back to 14 (instead of 12)
- Clause 7.1.2: Addition of longitudinal stringer
- Clause 7.1.2.4: Factors reduced to 0,35, 0,25 respectively (formulae (25) and (26)
- Clause 7.2.4: (No note could be found what should be inserted here)
- Table 9: Compromise values for glass content
5.3 Other specific items discussed
Deadrise angle: W.Turnbull proposed to use the LR way of definition. Concern was expressed that then the definition of β will differ in several ISO/TC 188 standards. No final decision.
Table 9: R. Eliasson proposed to reduce the values of this table to be safe with Table 10. The additional note is regarded as solving this.
Spray-up laminate: KJF promised to present a formula for spray-up laminate. Is awaited.
Min. skin thickness: KJF pointed out that the amount of fibre content is more essential than the thickness.
Sandwich construction: This part raised controversial discussion on many of the details, key words being:
- unbalanced skins : danger of shear failure,
- if weight optimised, then formulae are critical,
- core density often ignored,
- toughness of resin,
- influence of composition of laminate (CSM/WR/UD)
General: Application of Table 10 for mixed laminates: Proposal to give examples
These items have to be further discussed and decided.
6. Simplified approach
The question of adding a simplified method as an annex to the standard had been discussed several times. There was more or less consensus reached that this should be done by merely reducing the number of parameters by using constants instead, but not to use a totally different approach.
Before the meeting T. Kano (JCI) had submitted a draft proposal for such an annex (Doc. N-116). Further comparative calculations were presented for the lengths of 6 m, 9 m, and 12 m, as it had been agreed that this should only apply to boats with a length of up to 12 m.
The approach was regarded feasible, though possibly needing some additional explanatory remarks as to the use of load assumptions.
It was decided to deal with this in more detail at the next meeting.
