ALSO PROJECT Z-THETA9 (http://en.wikipedia.org/wiki/Theta) Theta (uppercase Θ, lowercase θ) is the eighth letter of the Greek alphabet, derived from the Phoenician letter Teth. In the system of Greek numerals it has a value of 9. The lower-case letter θ is used as a symbol for: A plane angle in geometry.

PROJECT X21-B Might be interesting: http://en.wikipedia.org/wiki/Northrop_X-21 ?