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Joined: Sep 2005
Posts: 421
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Thanks Marc, I went looking for pictures and ZI see what you mean . the Dash 7 could in no way be confused with the later styles


Tom
Joined: Aug 2001
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Originally Posted by Texas_Ranger
Supposedly the tail light was on the same series as the inside light... (those old cars had 95V incandescent bulbs wired in series to the 750V DC traction power). So, the rear of the train was dark.


That sounds like a very bad design when a blown interior light can take out an important tail light. In fact the whole series wiring business for interior lighting raises issues, such as the first few lamps in the chain being at such high voltages.

London Underground (subway system) had a horrendous accident in 1975 when a train smashed into a dead-end tunnel at Moorgate station. There never was a definite conclusion drawn as to the cause:

http://news.bbc.co.uk/onthisday/hi/dates/stories/february/28/newsid_2515000/2515033.stm

Extra safeguards were put into place at terminal stations though. They added standard tripcocks (used to emergency brake a train going through a red light) ahead of and part way along the platforms of dead-end lines, and had them operated by an approaching train with a time delay. The delay was set so that if the train was exceeding 10 mph it would reach the midway point before the tripcock was lowered and be stopped short of the tunnel end.

Joined: Dec 2001
Posts: 2,498
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Indeed, those old cars did have a few serious design faults or rather were just plain outdated.

The original design was from 1924 and during the 1950s new cars were built reusing some old parts as well as parts of the design. Since the new cars had more lights I assume the circuit design of the cars in question dated from 1953 and still showed post-wartime shortages.
The pneumatic brake system was reused too, and that caused severe trouble in the last few years too, though I suppose that was mainly due to severe maintenance issues. Aside of that, compared to modern brake systems those old cars were scary anyway!
In general, the series wiring never caused problems and is still in use in older cars (up to 1976 new cars did not have inverters for the lights and several hundred of those are still in service, I guess around 250 motorcars and a similar number of trailers). All later cars had 24V DC battery operated tail lights though as well as interior emergency lights.

In the late 1960s the city decided to convert the old subway system to high platforms (95cm instead of 35), third rail instead of catenary, electronic signalling instead of light signals and the possibility of autopilot. During the transition period the old system deteriorated more and more, the electromechanic signalling system dated from 1925 after all and had only seen minor upgrades in 1965 when the system changed from mechanical tripcocks to magnets. Maintenance of the old cars was more or less cut until severe accidents required immediate action. Then cars were pretty much rebuilt, sometimes only months prior to being scrapped. The last of the legendary red 2-axle cars was in service in 1983.

Joined: Jun 2002
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Does anyone know about when this collision occured
(Nearest month, year at least)?
It is possible to view NTSB reports and investigation
data on-line.
Also, Trains Magazine's "Newswire" reports some collisions
and results of investigations.

Scott, I'm like you - I gotta know.
and I'm betting it's CTC territory. Maybe we should ask
Al Krug for an expert opinion? (alkrug.vcn.com/home.html)

Energy7
(At least it wasn't SP !!)

Joined: Jun 2002
Posts: 58
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Here it is, everyone:
June 14, 2006 - at Madera, CA
on the BNSF Stockton Sub: BNSF 4059 vs. BNSF 4479
Conflicting reports regarding injuries.
If anyone finds the NTSB report,
I'd like to know, thanks.

Energy7

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