The ZTL and ZAU division of roles probably evolved to handle particular requirements of those types of centers.
The first interview procedure was open-ended and was used in ZKC, ZAU, and ZTL to explore the range of benefits provided by strip markings/ activities and to see the benefits that would naturally emerge.
Of the 196 controllers invited for interviews from ZDC, ZAU and ZTL, 186 complied.
9, 2002, he hooked the ZAU to a John Deere plow and broke sod just to see if the old girl still had it in her .
It's popularity is evident in the production figures: Minneapolis-Moline produced more than 17,500 units, averaging more than 4,000 ZAUs each year of its production run, 1949 to 1952.