Edited 14 Dec 2013 11:00, 8 years ago, edited by Sulla1

The big issues for the D58 was not having enough adhesive weight for a tractive effort of 55,008lbs, and retaining three cylinders, a concept abandoned by US builders by 1930 due to the much higher cost of maintenance. At a time when cheaper diesels were become available, the D58 design needed to be cheap and practical to run, and it wasn't. The way I see it the designers should have adopted one of two choices...

1. If the tractive effort was more important, then the adhesive weight should have been increased to at least 223,850lbs. A two cylinder D58 built to that standard would have had cylinders 23.5x28, boiler pressure of 255psi and a tractive effort of 55,860lbs.

2. If the adhesive weight could not be increased (most likely) tractive effort should not have exceeded 52,455lbs for the 212,000lbs on the drivers. This design could use a pair of cylinders 23x28 with a boiler pressure of 250psi.

Hard choices needed to be made during the design phase, and ultimately the compromises made were the cause of the D58 debacle.