We need to define the "Naugy" in three pieces. 1. Devon - Derby Junction had all of the Waterbury passenger trains plus all of the Maybrook freight trains and some of the Waterbury freight trains as well. 2. Derby Junction - Waterbury had all of the Waterbury freight trains and passenger trains. 3. Waterbury - Winsted had one local freight daily later reduced to six and finally five days a week and not more than three days a week between Torrington and Winsted. Piece 1 had any power on the New Haven on freight trains to and from Maybrook including occasionally L & H R, Erie, PRR, B & M and probably others as well. Derby Junction had mostly RS-3's although the Hartford - Maybrook jobs generally had 0400's mostly in 3 or 4 unit sets but occasionally 2 units. The tonnage was much heavier between Waterbury and Derby Junction so although the grades were heavier between Waterbury and Hartford the tonnage was generally much lighter and in this case two units would sometimes do. Waterbury - Winsted was RS-3 country although in earlier years they ran RS-1's and RS-2's in and out of Waterbury on both passenger and freight. In the late 1950's they ran a Oak Point - Springfield job and that had three units of almost anything, this job ran after the bridge fire in Cedar Hill which the railroad was originally not going to rebuild but eventually they decided to rebuild the bridge and re-open the West Hump. After Penn Central took over the New Haven the trackage between Devon and Derby Junction could and did have almost any type of power that the Penn Central operated although if they ran "F" units over this territory it was very uncommon. Six motor units were not uncommon in this territory either. Boston and Maine Budd Cars were used on the Naugy at various times when the NHRR was short of them, they could run them between Bridgeport and Waterbury and between South Norwalk and Danbury because neither line was cab signal territory at least during the NHRR years. After Penn Central took over former NYC Budd Cars were occasionally used on both of the mentioned branches as well. Noel Weaver
After further research, I revised my list again. Here is my revised list of locomotives used on the Naugatuck Line (and on the Highland to Plainville) from 1969-1995:
Penn Central (1969-1976): Lower Naugatuck Line (Maybrook-Cedar Hill Freights): RS-3, U-25B, U25C, U33B, C425, GP40 Upper Naugatuck Line (including Highland to Plainville): RDC-1, RS-3, RS3M (Plainville only), RS-11, GP9, S3, SW1200 (Derby Switcher)