Class Leader on train 13Z 

Are you familiar with the term Class Leader? It's not one I hear very often in US railfan circles, maybe it's a foreign concept! Put simply, it's the first locomotive of a given type on a railroad.
For a specific example, this example of NS train 13Z is being led by NS8000, the first numbered unit of the railroad's 184 ES44AC units, delivered in late 2008.
Norfolk Southern were somewhat late to the "AC" party - with a few notable exceptions, the entire fleet was DC-powered for a long, long time. Apparently the AC-experiment was successful, as they have purchased a few variations and included a DC-to-AC conversion in some of their rebuild programs for older mainline locomotives over the last decade or so.
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Zoom H6 (Audio Recording) -- amzn.to/3B4kQUF
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