Were there any lines that the DL109s and/or the PAs were restricted from due to their long wheelbases?
Engine type restrictions were listed in the Time Table in Rule 1710 (according to the April 29, 1951 issue).
For PA-1s and DL-109s any restrictions would have been on lightly-used branches with no passenger service. Also, any restrictions would be due to the engine's weight, not its length or wheelbase. A DL-109 could handle a curve as severe as 21° (274.37 ft or 83.63 m).
New Haven/Hartford Division restrictions were as follows:
Branchville and Ridgefield - DERS-3
Canaan and Lakeville - DERS-3
Highland Jct. and Watertown - DERS-3
Vernon-Ellington and Rockville - DERS-3
Farmington and New Hartford - DERS-3
Northampton and Williamsburgh - DERS-3
Boston/Providence Division restrictions were as follows:
Providence and Bristol - DER-2
Westdale and East Bridgewater - DERS-3
Tremont and Fairhaven - DERS-3
New Bedford and Watuppa - DERS-3
Franklin Jct. and Hopkinton - DERS-3
Note - The DERS-3 was the Raymond Loewy-styled FM H-16-44 (0790 series). The DER-2 was the Alco FA-1 (0400 series).