It looks like Namco obtained licenses directly from the manufacturers. The title screen has a big, dense list of licensing information regarding the planes from

It looks like Namco obtained licenses directly from the manufacturers. The title screen has a big, dense list of licensing information regarding the planes from Dassault, Boeing, and seemingly a million other manufacturers. I'm not sure exactly what parts of the planes require licensing. Do you need to pay to use their names? Their likenesses? Both? Neither? Maybe it's just a courtesy? It's a good question. I'd love to know more myself.