Its the blade section of the wing, its cracked through as its taken on water so I presume it is structural, we've had to drill a small hole to let water out, but it doesn't creek or make any noises. Will probably look at filling it, dad seems fairly confident after flex testing it that that might be ok. More confident with filling it than carboning it at the moment. Will give it a test on Sunday and if it doesn't work out it'll give us plenty of tine to get it repaired before QM.