While this thread has taken a different direction, we'll comment on "universal" rail cars.
The LIRRS's first MUs, the MP41's were as narrow as the IRT cars as they were designed for joint operation. They were equipped with with sliding trap plates that could fill the platform gap in subway stations. Some of the subway cars used on the joint Rockaway Service via the Chestnut Street Incline had adaptable third rail shoes that accommodated the different subway and LIRR third rail spacing.
They were very similar to the era's subway cars with similar car bodies, propulsion equipment and automatic car stops on the air brake system that were in use on the subway and the Atlantic Avenue tunnels.
The LIRRS's first MUs, the MP41's were as narrow as the IRT cars as they were designed for joint operation. They were equipped with with sliding trap plates that could fill the platform gap in subway stations. Some of the subway cars used on the joint Rockaway Service via the Chestnut Street Incline had adaptable third rail shoes that accommodated the different subway and LIRR third rail spacing.
They were very similar to the era's subway cars with similar car bodies, propulsion equipment and automatic car stops on the air brake system that were in use on the subway and the Atlantic Avenue tunnels.
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