An outbound train of M-1 cars pulls into the Hewlett, Long Island station. One of the most radical decisions taken in the design of these cars was to forego compatibility with the existing multiple-unit (MU) fleet in operation at the time. This was possible because the intention was to completely replace the ancient existing MU's, making possible major performance improvements that would have been unsafe if old and new equipment had operated together on the close operating headways typical of the LIRR.
