I just finished publishing a YouTube Video that was from footage of a Hang Gliding competition in the mid 1970's. Lot's of Wills Wing product, Delta Wing, Seagull, Easy Riser, Mitchel Wing and others going for the Bulls eye as well as a few of the aerobatic component. I am trying to get input to see if we can identify makes and models as well as names of pilots that are shown. I am pretty sure a lot of the big names of the day were attending.
Looks like the Hang Ten World Open, held at Escape Country, Southern California, April 10th - April 18th, 1976. It was written up in the May 1976 issue of Ground Skimmer Magazine (USHGA). A DVD copy of the entire collection is available through the USHPA office. Comparing photos in the article with the video would allow identification of some pilots and gliders.
Just from quickly watching the video, I can make educated guesses on some of the gliders:
4, 5, 10, 24, 28, 30 - Wills Wing SST
7- Mitchell Wing
14 - Seagull 7
20, 21, 22, 23 - Delta Wing Phoenix 6B
I saw what were probably two Sun Swifts, and the truncated tip gliders would have been either UP Dragonflies or Eipper Cumulus V's in all likelihood.
Bob flew in the meet, and finished 9th. Brian Porter won it on an Easy Riser.