Norfolk Southern's cab units: Among the most technologically advanced streamliners around

Norfolk Southern's four executive cab units roll through Harrisburg, Pa., in August 2012. The units have seen substantial internal upgrades since their debut in 2007. Jim Wrinn photo

ALTOONA, Pa. — We’ve all come to admire Norfolk Southern's set of four tuxedoed cab units' two As and two Bs that create that "perfect" ABBA set of streamlined Electro-Motive Division engines that were the norm in the 1940s and 1950s. Lovingly restored with great attention to exterior details' they look right at home in the Southern Railway-inspired paint scheme hauling NS’s business car train. But if you go inside one, you'll find an amazing contrast to the classic look on the outside: The guts are as modern as can be.

The engines got many upgrades when they were rebuilt in late 2006 and early 2007, but NS has continued to bring them along, year-by-year, into an even more modern state. They are probably on par with any other set of executive office car train units that have been overhauled in recent years, says Allen Rider, manager of locomotive engineering for NS. “Once we got them out running, one of the first big projects about a year later was to add ECP (electronically-controlled pneumatic) brakes” in place of the standard 26L brake system,” he said in a phone interview.  For those who don’t know, ECP brakes enable the use of graduated release braking, a feature long gone from the remaining passenger cars of most freight railroads. This allows for smoother braking efforts and is an enhancement for train handling.

Thus, the engines got New York Air Brake’s microprocessor-based CCB II brake system and its LEADER train-handling computer to assist the engineer (LEADER, by the way, stands for Locomotive Engineer Assist / Display & Event Recorder). The units are also ready for the installation of Positive Train Control gear when the time comes. All this new equipment required plenty of engineering, especially for the A-units which have relatively small cabs compared to modern locomotives. The craftsmen at Altoona once again displayed their knack for innovation by fitting six bushels of equipment in a five-bushel basket.

Last winter, after the inspection train returned home to Altoona, Pa., the famous crews at Juniata Shops focused on the B-units. They recabled and rewired them, replaced the D12B DC generators with more reliable AR10 traction alternators, eliminating brushes and transition. Completely new electrical cabinets with TMV Control Systems Inc.’s TECU microprocessor control system replaced the somewhat upgraded B-units. “Those locomotives were rewired some time in the very distant past by Chicago & North Western,” Rider says. “Nothing much was changed other than the wiring. They retained their original Funit control systems. NS made a few upgrades in 2006 like adding Quantum transition panels and upgrading some of the pneumatic switchgear. Beyond that, the locos were pretty much out of their 1950s box.”

The A-units are next with 4271 entering the shop on Nov. 7. The other A-unit, 4270 will be upgraded during the 2014-2015 winter season. Morrison-Knudsen rebuilt and rewired these locomotives in 1981, and their control systems were upgraded to basically that of a GP38. They got electromagnetic switchgear, higher quality Exane wiring, but kept load regulator excitation and did not receive Dash-2 modules.  So, after 32 years of service, it’s time for another upgrade.  They will receive the same treatment as the B-units.

So what’s next? Only time will tell, but through all of the changes, one thing has remained constant: engine horsepower. While still set at 1,800 hp. per unit, the locomotives have actually gained tractive effort with the new control system.  For these units, on the outside, it’s strictly a 1950s appearance, but on the inside it’s all 21st century railroading.