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| Re: Speed (1510981) | |||
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Re: Speed |
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Posted by randyo on Thu Apr 25 15:26:37 2019, in response to Re: Speed, posted by Express Rider on Wed Apr 24 13:42:59 2019. I was just making comparison between the Chicago cars and the BMT el cars since by the time of the first 4000s the state of the art for braking was AMU with M-23 brake valves. Although I don’t have any hard info, It’s highly possible that the older Chicago el cars may have had the AML brake system since being pneumatic only, cars with both brake systems could be operated in the same train. The few Chicago wooden museum cars I have seen have the same motor control and brake systems as the 4000s but I was told that the original controllers were similar to the BMT el cars (described to me as “elevator type). According to what I saw somewhere, the Manhattan el cars and as originally delivered the Gibbs and deck roof Hi-Vs ad Christensen brakes and not Westinghouse although I can’t understand the advantage of going to a non WABCO manufacturer since WABCO owned all the air brake patents at the time. From the photos I have seen of MP-41 engineers’ cabs, the LIRR MP-41s also had Christensen brakes. Initially, both IRT el and subway equipment had Van Dorn link and pin couplers as did the BMT el cars. As the state of the art progressed, electro pneumatic brake systems and semi automatic couplers were developed and installed on the IRT subway fleet. I suspect, they weren’t installed on the el fleet due to weigh considerations. By around 1910, all the IRT subway cars were equipped with E/P brakes and semi automatic couplers. The F and J drawheads as used on the IRT were not fully automatic even though they included air connections in the coupler head as the angle cocks had tp be opened and closed manually when coupling or uncoupling. When the Composites were transferred to the els, several modifications were made. The original Hi-V controls and AMRE brakes with ME-21 brake valves were replaced by Lo-V controls and AMUE brakes with ME-23 brake valves. The trucks were replaced with maximum traction (1 motor per truck instead of 2) to spread the weigh for use on el structures. The original transverse cabs which were similar to the Gibbs cars were modified with the original end door being used as a cab door and sliding end doors added. The original controls, brake equipment and trucks were installed under new steel bodies the IRT recently purchases and these became the Flivvers. The manual 12 point Hi-V series/multiple controllers were retooled as 3 point Lo-V controllers with automatic acceleration. Some of the old time IRT el men mentioned that there was a train of MUDC Manhattan el cars that was outfitted with electro pneumatic brakes but I was never able to get any further info about it or which type of E/P brakes were installed. |
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