Probably a dirigible. If the dirigible was traveling at the speed of the wind, her hair would be still.
If she were in a fixed position, her hair would be blowing around, a good indication that it was a dirigible.
Not a composite at all, just a very good historical photograph.
That would be such a cool way to travel. You could spend the whole trip on the observation platform sipping mint julips.
I'm not aware of any dirigibles with an exterior catwalk that have been flying since the World Trade Center was built.
So HOW did the photographer get so high up???