GG1 4877 posted:The second NH order for FL9s were all delivered in 1960 with 567D prime movers. The first 30 built in 1956 had the 567C prime movers. I'm not sure there are any external differences other than the NH orange used between the first and second order was a different shade.
I've heard that there was talk of designating the second group of FL9's "FL18."
Stuart