FAQ #282
F.4.3.5c Directional Strength And Stiffness

Last Updated On 2019-12-02 16:46:56 ET by

sayovitz

Question
What does a CHECK readout mean in the SES Composite directional strength and stiffness dialogue?
Answer
The SES defines the directions where the F.4.3.5c is being enforced.
For 2020, teams have the options of meeting the 50% requirement at 90 degrees, or at +60 and -60 degrees.
If the SES tool is not throwing a REJECT code for your layup, it is most likely acceptable.

We discourage any extremely low values.
A CHECK readout below 50% could point to a failure of G.1.4 Good Engineering practice.
For example, ply choices and directions to minimize strength except for the 0 and 90 directions.

Many sensible and acceptable layups for 2020 we tested returned a CHECK readout (below 50%).
No Attachments
Rule Numbers
2020:F.4.3.5C