We had our 150 tied down outside for a few years. I used the double half hitch, rudder gust lock and control wheel lock. I positioned the airplane so the wing tie down rings were slightly "behind" the ground anchors, then used the tail tied down rope to pull the airplane back slightly and slightly tension the wing tie downs. The result was the wing tie downs were slightly angled. We had thunderstorm winds a few times up to 60 mph or so. I am not a big fan of chains or metal ends. I prefer just good nylon rope so the tie downs can give a little. I always ran out to the airport (only 3 miles from home) anytime thunderstorms were forecast to make sure everything was in good shape. I am glad to be in a hangar except when I have to write the rent check every month
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