[GreenKeys] Skywriter

[Jim Haynes]

I was at a hamfest this morning, and some fellow dropped off a couple
of old issues of Popular Science magazine that he didn't want to take
home.  I flipped through one and saw an article about Skywriter.  At
first I thought it was some kind of teleprinter for use in airplanes.
But, no, it was a patented system in which seven airplanes fly in
formation side by side and release puffs of smoke to spell out words
across the sky in dot matrix.