what the f.. if i was b777 i would be so pissed. this isn't baseops.net, people.
Ok, ok. You're right. It was just too tempting to resist messing around a little bit.
The billboard panels that I used to fly were all made one of three ways. They either started with plain ripstop nylon in whatever the background color was and painted everything else onto it. Or they cut everything out of different colors of ripstop nylon and then glued/sewed at all together. Or they could a combination of the two.
The painted panels were cheaper to have build (less labor involved) but they were heavier to tow. The sewn panels cost a lot more to build, and limited what you could put on the panel to text and simple logos. But they'd end up looking really good and they'd be really light for their size so you'd use less fuel to tow them.
Once in a while you'd see a panel where they started with white nylon and painted the entire background a different color and then painted the graphics on top of that. I used to call that style of panel the widowmaker because they were so heavy to tow.
I've never seen any panels that were machine printed with ink. But I'd guess it would possible. You'd need a printer that could print on fabric strips that were probably 10ftx100ft and then you'd have to align and glue/sew the strips together to form the panel. Like I said, I've never seen it done but I also haven't flown a banner in several years now.
FWIW though, I really like my story about the giant iron and ironing board. My inability to resist telling such stories is just one more reason why I should never have children.