Slo-Mo-Shun IV

[785boats]

Hi guys.
I managed to pick up a vintage Billings kit of the Slo-Mo-Shun IV for a couple of hundred Aussie Bucks.
I'm just wondering if anyone can tell me the theory behind the big hole in the heel of the right sponson on the full size boat. I've noticed it in pics of a few boats around this era.
Here's a few pics. one of the kit & some of the full size boat.

[leonard feeback]

Hi, that area or hole is called a wet sponson. In the 40's 50's and early 60's most hulls had those holes. Early unlimited leaked some other a lot. Those holes let the hulls dry out after a race. You may have noticed that when the hulls are lifted out of the water a lot of water drains out. On the secondary running surfaces you can see small square holes, those are drain holes while the boat running and on the trailer also. Scale model boats as 1/10th put a black circle on the back of our sponsons to model that hole. Hope this helps.

[JimClark]

Leonard has it right
Chesk out his video at about three mins you will see the water emptying as it gets up on plane

[785boats]

Thanks fellas.
That clears it up for me.
Great video Jim.

Cheers.
Paul.