Friday 19 June 2020

A pair of great disappointments, Tucson, April 2000

UP double stack intermodal train passing south into Tucson, AZ. As a historical note, on March 20, 1882, two days after the shooting death of Morgan Earp, Wyatt Earp led a posse that hunted down and killed Frank Stilwell in the Tucson railyard, lying further south.

The SD90MAC-H, powered by the 16 cylinder 6000 hp 265H engine was a rare beast, as only 4 were completed for Canadian Pacific, and 62 for Union Pacific. At this time, the 4 stroke 16 cylinder H engine was under-developed and suffered issues. Some SD90MAC-H locos lasted only about 5 years, all were gone from CP and UP by 2009.

The majority were completed as SD9043MAC which were 4300 hp 'convertible' locomotives using the 16 cylinder 710G3B engine, with a view to later conversion to the H engine. Given the problems with the H engine, none were ever converted, many of those remaining have been rebuilt by later operators, notably Norfolk Southern.

The 4 stroke engine has been later developed into the 1010 engine, which is currently offered at 12 cylinder 4500 hp.

GE offered the AC6000CW which was powered by the 7HDL-16 engine at 6250 hp, jointly developed with Deutz. This suffered from vibration issues, and only 317 locomotives were produced from 1995 - 2001, for CSX and Union Pacific. The partnership with Deutz was subject to legal proceedings, but GE developed the engine platform further into the successful GEVO series. The AC6000W locos ran for longer than the EMD offering, but many were changed to 4400 hp by software change, as already covered here for a CSX example. 

Above we can see both types, pretty much the first train which came along that day, good luck since I did not have much available time, I was not in town to see trains. Location, now much further developed.

  • 7517 GE Serial No 50951 was a AC6000CW, built July 1998, delivered in October that year, the 6000 hp 7HDL-16 powered competitor to the SD90MAC-H. Later UP 6904 in early 2009, following change to 4400 hp as a AC4460CW. Now scheduled for a rebuild into a C44ACM for UP.
  • Unidentified former SP SD40M-2 (rebuilt by Morrison-Knudsen using SD45 body)