Yes, all BT-30's were parallel wound until the 70's. The initial ones were apparently made on the Estes' kitchen floor (or maybe table) with manilla folders. I think they quickly got a tube company to make them with the manilla material, but they still looked hand wound! I have a couple right here. Maybe 1973 was the first spiral-wound BT30 I ever saw? I think the Mark II was the first kit utilizing the spiral-wound tubes.

__________________
Roy
nar12605