Green Line Type 9 Thread

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Re: Green Line Type 9 Thread

Postby Type7trolley » Wed Feb 27, 2019 7:02 pm

The Type 9 has cameras on both sides which I believe are displayed in the cab, so the mirror seems somewhat redundant.

Even if the mirror could be eliminated, the door cycle time will always be slower than other cars. Aside from the obvious factor of the single panel doors covering more distance to close, the end doors also travel at a slower speed than most two part sliding doors. They cannot simply be sped up to decrease dwell times, as APTA specifies maximum door closing force and a larger single piece door, having more mass, must move more slowly to impart the same amount of force as a smaller, lighter door panel. I wonder if the tiny windows on the front doors are an attempt by CAF to mitigate this. Glass is heavy.

I am sure that when Boston ordered all of its rapid transit equipment with single panel sliding doors in the 1910s & 20s, this was not a consideration.
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Re: Green Line Type 9 Thread

Postby jwhite07 » Mon Mar 18, 2019 8:01 am

According to NETransit, 3901 has been accepted for service. Hopefully they'll see more use in rush hours now that there is a 2 car train available.
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Re: Green Line Type 9 Thread

Postby diburning » Mon Mar 18, 2019 4:39 pm

I spotted the pair yesterday testing on the Cleveland Circle branch. 3901 was leading outbound, with the skirts removed, and 3900 was trailing, with skirts installed.
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Re: Green Line Type 9 Thread

Postby diburning » Tue Mar 26, 2019 4:56 am

jwhite07 wrote:According to NETransit, 3901 has been accepted for service. Hopefully they'll see more use in rush hours now that there is a 2 car train available.


3900/3901 debuted in rush hour service on the Riverside line on Monday Mar 25. Both cars had their truck skirts installed. 3902 is in testing and is roaming around without the truck skirts.
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Re: Green Line Type 9 Thread

Postby daybeers » Sun Apr 07, 2019 9:06 pm

I'm not often in Boston but THANK YOU for taking actual steps to advocate for better transit! I applaud you, Yellowspoon!
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Re: Green Line Type 9 Thread

Postby Disney Guy » Thu Apr 11, 2019 9:45 am

Type7trolley wrote:(snip) the door cycle time will always be slower than other cars. Aside from the obvious factor of the single panel doors covering more distance to close, the end doors also travel at a slower speed than most two part sliding doors. They cannot simply be sped up to decrease dwell times, as APTA specifies maximum door closing force and a larger single piece door, having more mass, must move more slowly to impart the same amount of force as a smaller, lighter door panel.(snip)

I am sure that when Boston ordered all of its rapid transit equipment with single panel sliding doors in the 1910s & 20s, this was not a consideration.

I suspect that the first reason for going to double panel center parting doors was limits on the space to the side for the door panel to slide to. The space limitation was surmounted (not completely on the Type 9 where the front door can hit the coupler) by the LRV plug door sliding track that came out from the car body and telescoped to the side and also provided all of the support for the door panel without door tracks on the body side.

Did a cursory check on line and the earliest instance of double panel sliding doors on transit equipment I found was the Boston home grown "two rooms and a bath" articulated streetcar! Various center entrance streetcars including Boston's had two panel sliding doors where the overall door width was somewhat greater than a typical rapid transit car doorway. While the weight of a single panel that wide might have been considered as too much for the door opener, the Boston center entrance cars (and perhaps others) had the two door panels linked so one door opener moved both.

The Orange Line 01100's (perhaps many other models worldwide) had one panel of a double panel door set halting when half closed and then closing the rest of the way more slowly. This prevented crushing someone but the door half that closed at full speed could hit someone quite hard.

The various pre-1920 rapid transit cars for Chicago, Philadelphia, and New York City had single panel doors, suggesting that double panel door sets had not become popular yet.
(To the theater stage manager) Quit twiddling the knob and flickering the lights while the audience is entering and being seated. (To the subway motorman) Quit twiddling the knob and dinging the doors while passengers are getting off and others are waiting to board.
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