Introduced in 1974, the A-Type had a flat envelope with a parachute rip, and came in three sizes: 56, 69 and 77 (24-32 vertical-cut gores).
Thunder Balloons A-Type
Introduced in 1974, the A-Type had a flat envelope with a parachute rip, and came in three sizes: 56, 69 and 77 (24-32 vertical-cut gores).
All Aero 