The first Thunder was Jumpin’ Jack (sometimes listed as Jumpin’ Jack Flash).
One of the early “Jack” balloons, TigerJack was built in 1973, and first flown in January 1974.
The 12-gore “Series One” envelope, patterned after Jumpin’ Jack, could be had in 5 sizes: 42, 56, 65, 77 and 84.
Variation:
Ruppenthal Eagle
All Aero 