The web pages are great and have been very helpful Ross, Thanks! They must take alot of your time. I think I can trust the underdeck bungies. They made a nice addition to my North Star.

I haven't calculated the Bernoulli effect with a difference of air speeds between the inside and outside of the hull of over 100 MPH with non-laminar flows and dog slobber and only a 1/16 inch vent hole in the bulkhead, but I think the pressure differentials could be significant and could change rapidly at times. I only used two attach points on the hatches, but I think you all are right and I'm going to take my chances. Something about first hand experience added to the sciences that makes it all more practical.

Thanks for the input

Doug