500e
Despite common misconceptions, fibre-glass is quite strong, probably close to the strength of some forms of carbon composites. What it lacks is stiffness. It stretches further for the same stress. The colour of the fibres in the fracture is clearly white, so it is glass.
I am hearing rumours (it is a rumour network, right?) that on other aircraft the surface of the composite at the end of the blade appears white, while away from the blade end it is a yellowish colour. Anyone else observe that? It could be significant. If the resin is a yellowish colour and in some regions the laminate apears to be white, it could be that the white areas are resin starved, with a high fibre-to-resin content.
There is an optimum resin content; too low and you loose strength because there are not enough fibres to carry the load, too high and you loose strength because there is not enough resin to transfer the load between the fibres. The resin content is controlled by the resin bleeding process during production. Bleed too much resin off and the laminate is dry and the strength is reduced.
Regards
Blakmax