Our "L"s Have Built More Flat Junctions Then Flying Ones

[chicagopcclcar]

A northbound Brown line slows while it awaits for the southbound main tracks to clear....minutes, just a minute, or tens of seconds....it depends on which side you believe in the controversy about the flyover at Clark Tower.

 

Cleared, a northbound Brown line train leaves the interlocking and prepares to enter the branch. Because the NB move came from track 4, no other opposite move can be made except a SB Brown line move.

Clark Junction is called a "flat junction." Chicago elevateds have built flat junctions though its history. The first was on the west side near Marshfield, then three junctions bringing the four surrounding "L" companies onto the Loop. On the south side similar junctions were built at 59th St, Stewart Ave, and at Indiana Ave. On the north side, flat junctions were found at Clark Tower and at Howard terminal.

In 1938 the plans for flying junctions were included in the Initial Subway with interfaces with current "L" tracks and the subway lines. Provisions for additional junctions were included in the State St. tubes at Roosevelt and in the Dearborn St. tubes at Lake and Milwaukee. In the 1950s a flying junction brought the Douglas Park into the Congress median. In preparation in the Congress construction, a temporary flat junction was built at Paulina Ave on the Lake St. "L". Removed from service, the junction returned with the creation on the Pink line.

In the late 1960s the new Dan Ryan bought a flying junction at 18th St. The same trackage would be used when the Orange line came into being.

[chicagopcclcar]

Two Orange line trains travel the routes through the "Grand Junction", the city's only in-service flying junction on CTA Rail.

 

In the discussion of flat junctions in use by the CTA Rail, only one flying junction is in service, the so-called "Grand Junction", 17th St. interlocking, used by the Green and Orange lines. The other day-to-day operations today are handled by flat junctions:  at 59th St. on the south side; Paulina Jct. on the west side; Clark Tower and Howard on the north side; and two flat ones on the Loop "L"....Tower 18 and Tower 12. Two other flying junctions are only used for transfer, work trains, another non-revunue moves.

Referencing the second photo at the beginning of this post, I think the lay-person doesn't take it into mind that more has to go on before a move can be made at Clark Tower.  Some people say it's only 20, or 30 seconds for a train to travel the distance through Clark Tower.  What they fail to account in their timing that it takes time to clear the first routing before setting up the next route. The Brown line train in the picture has to complete its move and clear, then the next move can be lined up. In the meantime, trains approaching have to limit their speeds, adding to their time. Often its these minutes that gets overlooked when the lay-person says it only took 20-30 seconds. 

DH

[andrethebusman]

All this crying about waiting a half minute at Belmont NB would be valid if the Brown Line was running a track capacity, i.e. - trains following each other on yellow signal blocks. Like rush hour in New York, where trains follow each other on 200-foot headways in some sections, one signal block behind. But this is just millennials with no patience wanting instant gratification.

[Busjack]

All this crying about waiting a half minute at Belmont NB would be valid if the Brown Line was running a track capacity, i.e. - trains following each other on yellow signal blocks. Like rush hour in New York, where trains follow each other on 200-foot headways in some sections, one signal block behind. But this is just millennials with no patience wanting instant gratification.

​And, of course, Emanuel and Claypool, who claimed to ride the Brown Line to Montrose, except when it turned out that Emanuel's motorcade was blowing by red light cameras.

Kevin O'Neil today made something about Carter saying he would be a commuter, like that means anything.

[chicagopcclcar]

 

A discussion erupted on the internet about is Howard North interlocking a flying junction because the Purple line and the Red line return loop goes over the Yellow line. That is incorrect. All the routes at Howard have to go through this flat interlocking. Because two routes go over a third doesn't make this a flying junction. So, only Grand Junction on the south side at 17th St. is the only flying junction used by regular revenue service.

[strictures]

 

A discussion erupted on the internet about is Howard North interlocking a flying junction because the Purple line and the Red line return loop goes over the Yellow line. That is incorrect. All the routes at Howard have to go through this flat interlocking. Because two routes go over a third doesn't make this a flying junction. So, only Grand Junction on the south side at 17th St. is the only flying junction used by regular revenue service.

Except that delays at Howard aren't caused by the junction, they're caused by the idiots & lunatics that run the Howard Tower. They think nothing of filling up both sides of the southbound platform with SB Red Line trains, so that SB Purple & Yellow Line trains can't get through to the turnback track, thus delaying NB Purple & Yellow Line trains.   That's Yellow Line trains when the line is running, not currently.

Or as I saw earlier in the spring, an 8 car 2600 train that had "NOT IN SERVICE" on it, pulled out of the west yard & then was berthed at the platform on Track 2. I watched the operator walk through all 8 cars, then climb down to the tracks & she then walked about 4 car lengths between Tracks 2&3, walk back, climb back up & then sit for another 5 minutes, before moving the train back into the east yard. All this time Track 1 was occupied & there were both Yellow & Purple SB trains waiting for that track to open up to drop off their passengers & turn back NB. There was a huge crowd on the NB platform & when I finally got on the Yellow Line train, it was the first time on a Sunday afternoon, where there wasn't a special event that the train was crowded. All told, it was a 25 minute wait for trains that run at 15 minute headways.

All because the Howard Tower is staffed with idiots & lunatics that seem to think they can ignore common sense in running a train system! Why wasn't that train moved south onto Track 1 which isn't used on Sundays & then moved back to get to the east yard? This situation happens repeatedly at Howard & it appears that CTA management either doesn't care or doesn't know about it.

[strictures]

Since management , operators, supervision don't post here, I fend for them.....does one event "I saw earlier in the spring" account for a charge of "idiots and & lunatics".  Is this a daily occurrence, do you commute daily or were you just visiting.

DH     

It's not one event, it's a regular occurrence at Howard or did you miss the last line?

Repeatedly, the idiots & lunatics in the Howard tower will fill up both tracks at the SB platform with Red Line trains, making it impossible for Purple & Yellow Line trains to let off their passengers & then proceed south to the turnback track. That occurs on a daily basis! For some reason, they will not hold Red Line trains on the loop track.

That earlier in the spring event was just weirder than the usual putting two Red Line trains on both tracks, but still blocking both Purple & Yellow Line trains.

[strictures]

I never get up to Howard so I couldn't make any statement.  There is a line manager in the second floor office.  He should be able to get answers for you.  

Going in calling them idiots and lunatics won't earn you points.

DH  

You think the manager doesn't know what's going on there? And I don't want to earn points, I want sane people to run the Howard Tower!

[strictures]

You never said you talked to supervisors, managers, 567 W. Lake. You've assumed "they know what's going on." So you've got a gripe about how they are handling two tracks...one and two....and this practice is holding up Purple and Yellow trains getting through to turn back and give northbound service.  What is not  clear to me why are you using my forum post to air this gripe.  My post is about that CRT/CRT has depended in using flat junctions in its operations. Your one example seems a train developed a defect.....lost relay??...I wasn't there....the switchmen searched through eight cars.... door defect which is the common cause. Then the switchman went down to track level....jumper switches lose contact....she checked the fourth and fifth coupling....that the only common coupling on the Red line, four cars couple up to make eight cars. If no cause was found, they took the consist back to east yards. Sounds like good trouble shooting. 

DH

WOW! Did you just make up crap!

You wrote that this flat junction holds up trains & I say that's total BS, it's the incompetence of the Howard Tower operators.

I never said it was a switchman, I said it was an operator.  She took the train out of the west yard, parked it on track 2 & then walked through the cars to get to the other end, to take it into the east yard, she never searched any cars, like so many other CTA employees, she didn't want to mingle with the unwashed passengers on the platform,. But she then decided to go out the end door of the now first car, walk down a few cars & then walk back. At no time did she ever look at anything, it was just a walk, which I believe was just to show off that she could walk a few inches from 600 volts. There wasn't any troubleshooting.

Everything you wrote was made up out of fantasy!

[chicagopcclcar]

 

A discussion erupted on the internet about is Howard North interlocking a flying junction because the Purple line and the Red line return loop goes over the Yellow line. That is incorrect. All the routes at Howard have to go through this flat interlocking. Because two routes go over a third doesn't make this a flying junction. So, only Grand Junction on the south side at 17th St. is the only flying junction used by regular revenue service.

 

The view from  northbound Green line as it approaches 17th interlocking, also named the "Great Junction." This is the only flying junction in regular revenue service.

DH

[andrethebusman]

You want to see a terminal with problems? Look at 95th/Ryan at night. Many times late night a SB train shows up at 94th and can't get in because there are two trains in the station. So you wait until one leaves. This is usually about 6-7 minutes, just long enough to miss the 34-S Michigan owl bus. It seems that whoever is in charge of that route is so obsessed with making sure that every interval leaves on time that they insist on keeping one more train on the road at night than what the schedule calls for, which is what causes this. According to the supervisor guide, there should be only one train in the station most of the time, so that the inbound can go right in. The next outbound is still not due out for about 7 minutes, so every train should have close to 15 minutes recovery time. But I guess this is just not good enough. With the extra train, recovery is now about 30 minutes (minus the wait to get in).

But this is not new, either. In the late 70's, Jefferson Park (which was the terminal back then) used to back up to Montrose, nose to tail, after the PM rush because the yard foreman would ignore the schedule that said to lay up two trains about 5pm and keep everything turning until much later, again because everyone was obsessed with getting every interval out on time. What's with that at CTA? Leave homebound passengers sitting fuming outside the terminal so that their "on time performance" does not risk missing an interval by a minute or so?

 

 

[Busjack]

You want to see a terminal with problems? Look at 95th/Ryan at night. Many times late night a SB train shows up at 94th and can't get in because there are two trains in the station. So you wait until one leaves. This is usually about 6-7 minutes, just long enough to miss the 34-S Michigan owl bus. It seems that whoever is in charge of that route is so obsessed with making sure that every interval leaves on time that they insist on keeping one more train on the road at night than what the schedule calls for, which is what causes this. According to the supervisor guide, there should be only one train in the station most of the time, so that the inbound can go right in. The next outbound is still not due out for about 7 minutes, so every train should have close to 15 minutes recovery time. But I guess this is just not good enough. With the extra train, recovery is now about 30 minutes (minus the wait to get in).

But this is not new, either. In the late 70's, Jefferson Park (which was the terminal back then) used to back up to Montrose, nose to tail, after the PM rush because the yard foreman would ignore the schedule that said to lay up two trains about 5pm and keep everything turning until much later, again because everyone was obsessed with getting every interval out on time. What's with that at CTA? Leave homebound passengers sitting fuming outside the terminal so that their "on time performance" does not risk missing an interval by a minute or so?

 

 

In both cases, isn't or wasn't there enough track past the platform that a train could pull through waiting for its return time?

It especially doesn't seem to make sense that the incoming train would be held just so its passengers would miss the owl bus.

[andrethebusman]

In the case of Jefferson Park, the turnback was the crossover under the Milwaukee Av Bridge. If there is a train in the SB track in the station waiting to leave, the train sitting past the crossover can't come in to the station until the previous one leaves. In turn, the one sitting on the NB track in the station can't pull into the turnback until the one already there leaves. In turn the next NB is at Ainslie waiting to get into the station, as is the one behind at Lawrence, etc.

95th has two tracks and trains cross over north of the station. If both tracks are occupied, one by the next train to leave and the other by the one after that. the SB is stuck north of 94th.

You see what the problem is - too many trains on the road. Per schedule, at 95th most crews are supposed to drop back one train, i.e. take out the train that their follower brings in. However, with the extra train in the rotation, the crew takes the same train as they brought in.

Another grotesque example of how CTA local management has a way of thinking they now better than the schedule department was how the 95th to Garfield and 95th to 63rd shuttles were operated during the Ryan shutdown. Schedule Dept made up specific schedules for 103rd to follow, but the garage manager decided "I know better". So the way it was run was a bus left every 10 minutes all day for Garfield and another right behind it for 63rd. At the other end basically the same way, every 10 minutes something leaves. When you got back to 95th, you joined the lineup on State and next trip was to Garfield or 63rd, depending on where you were in line. This resulted in horrible overloading at times, especially at Garfield in the evening, as the supervisor there would not let a bus go until the 10 minutes were up from the previous bus, no matter how many were aboard. Otherwise, what if the next NB is late, and there is no bus there for a few minutes? God forbid! At the other end, 95th, they would not send any more buses out also, as again what happens if the SB is late and there is nothing to fill the next 10-minute slots? This resulted in every single run out there doing 12 hours every day, and this is why downtown started getting all worked up about part-timers getting 60 hours a week.

Now 77th, which had the 79th and 87th shuttles, ran according to the schedule department's planned schedule, and they did just fine. NO excessive OT, and very little problems, because 77th manager was willing to trust schedule dept in knowing what they are doing.

 

[Busjack]

...

95th has two tracks and trains cross over north of the station. If both tracks are occupied, one by the next train to leave and the other by the one after that. the SB is stuck north of 94th.

...

Jefferson Park being moot, the question still is why doesn't the southbound train blocking the platform pull into the yard (or somewhere south of the platform), wait its time, and then pull up to the northbound track?

[chicagopcclcar]

How this topic was diverted into terminal problems seems to have run it course....let's begin anew. Flat junctions in the "L" system began with the third elevated builder, the Metropolitan West Side which built the Douglas Pk, the Garfield Pk, the Humboldt Pk, and the Logan Sq. The Met had it in for parks, LOL. The Met had a four track mainline from Franklin to a half block west of Ashland where there was a junction called Marshfield. Three lines branched off here including the Douglas and the Garfield in the first of flat junctions. A second flat junction was located just north of North Ave. where the Humboldt turned off. The Met opened in 1895. Meanwhile on the Lake St. elevated built a third flat junction that marked the extension east from Market St. and began the construction of the Loop elevated as the Lake St. line built east towards Wabash Ave.

An incident happened at the Market St. junction....looks like too  much speed.  CTA collection photo.

   

[chicagopcclcar]

Nothing remains of the old Marshfield junction. It was torn down with the building of the West Side Expressway, now the Eisenhower Expressway. The picture here shows the site as it looks today. The Douglas Park used a straight north-south connection that took north to tie it in with the Lake St. "L" during expressway construction.  The Garfield Pk was relocated to run at street level in W. Van Buren St. during the same construction. When the West Side "L" opened in the 1950s, the route was called the West-Northwest line and the Paulina connection reverted as a non-revenue trackage. Currently, the Pink line reopened the Paulina connection to revenue service.

[chicagopcclcar]

By 1895, three flat junctions had been built. Within two years six more flat junctions would be added, all connected to the building of the famed Loop "L". Why was the Loop necessary?  The three elevated companies all had an independent and separate downtown location...the Lake St "L" had its Market  St. terminal; the Metropolitan West Side had a terminal at Franklin St.; and the South Side Alley L had a one-track terminal at Congress.  The Northwestern Elevated  was still building and in 1897, it was not opened yet. But these terminals were all on the fringes of the downtown. The competitor cable lines and horse line went through the downtown areas and enjoyed much more convenient passenger drop off points.  The elevated loop would be built over Wabash, Van Buren, and Fifth Ave. (Wells St.). The north side of the loop was already being built in 1895, on Lake by the Lake St. elevated.

Lake St. building through the downtown at Lake St. just west of Wabash. Note, the steel for the State-Lake platform in the background.  CTA collection.

A two-block connector would be built over Wabash to tie-in the South Side from Harrison to Van Buren.  The "T" junction at Van Buren would be known as Tower 12. An another two-block connector would be built over Van Buren and a connection onto the Loop with another "T" junction at Fifth Ave known as Tower 8. At Fifth Ave and Lake the Lake St. completes its tie-in with a junction known in history as Tower 18. Three years after the Loop "L" opened, the Northwestern completes the complicated trackage at Tower 18.  The Northwestern did not have a side terminal at first but had to build one off of Wells at N. Water St. with the a flat junction included.  All nine junctions we have discussed, only two are in service today.

Tower 18 junction looking north. Over the years, the layout of the junction would be changed as operations and direction of travel change on the Loop L. CTA collection. 

     

Edited July 4, 2015 by chicagopcclcar

[chicagopcclcar]

This is the Alley L Indiana Ave station in an original layout. The elevated was two track, the Junction RR serving the Illinois Central on the lakefront and the Stockyards. Note the 90 ft. curve at Prairie Ave., just like the Loop L. Chicago History Museum photo.

With the famous Loop L finished, attention would swing to the south side where a huge third track construction project from 12th St. to 43rd St. to bring express service. Two branches would tie into the mainline at Indiana Ave featuring a flat junction for the new Kenwood tracks and switches joining the stub ended Stockyards track south of a middle platform.

 

Views of the Kenwood flat junction and other changes like a bigger curve at Prairie Ave, and elevation of the Junction RR. CTA collection photos.

Further south at 59th St. a new flat junction brought the tracks of the Englewood branch to the mainline. The branch would have another flat junction  at Stewart Ave. where the Normal Park branch left the Englewood branch.  Although the Normal Park only had three stations, all three had six-car platforms.  And most people believe nothing over two car trains ever ran on the tracks to 69th St. 

In the 1950s a four-car NB Howard hit the curve with too much speed and this derailment ensued. A brick building next to the curve and a steel girder kept the front car from going to the ground.  Your author heard the noise but went back to sleep, LOL. CTA photo. 

Of the three flat junctions discussed this time, only the 59th St. junction is still in service.  2400 series are on this Green line rounding the curve on its way to Ashland-63rd.

[chicagopcclcar]

Marty Bernard photo Dec. 12, 1972.  Chicago Transit Authority 6000 Series Cars on a Ravenswood NB crossing over at Clark Tower shot from the Belmont Station. 

Marty Bernard photo Sept. 22, 1972.
A Chicago Transit Authority Ravenswood A Train on track 4 is about to cross the four main tracks and continue north to the Kimball terminal. The Ravenswood of those days is not like the Brown line today.  Note the shiny tracks.  Ravenswood trains did not go downtown at off-peak hours and on weekends.  Ravenswood just ran shuttles between Kimball and Belmont and passengers transferred to North-South subway trains for the trip to the Loop. The shiny tracks show the route of shuttles through the interlocking and back to the branch.

 

While the south side was busily building the Northwestern was busy too. The elevated was also involved in real estate but its plans to build a branch along Irving Park Rd was stymied by the city.  The city accepted a route leaving the four-track main at Roscoe Ave and a flat junction was installed there.  The control tower was built on the west side of the tracks at the end of a local station named Clark. The Ravenswood branch had three 90-degree curves that were well endowed with 300 - 400 feet radius curves. Opened in 1907, the flat junction is still in service today.   

 

 

Edited July 5, 2015 by chicagopcclcar

[filmteknik]

Why do so many crossovers overlap, requiring a diamond (a high wear item)?  I can understand this in the subway where a large opening is more costly than the separate tubes so better to do one compact one and overlap them than two or a longer one for non overlapped crossovers but I don't understand why this is preferred in open air?  What am I not getting?

[chicagopcclcar]

The Skokie Valley bypass goes off on the left.  The tracks going up the "hill" are leading to Evanston and used by the elevated and CNS&M's  Shore line which closed in 1955. The yard tracks on the right were also used to turn elevated trains that terminated at Howard.  A loop track encircling the yard was installed in 1950 by the CTA speeding up operations.

 

The last flat junction came during the middle 1920s when the Skokie Valley High Speed Bypass was constructed by the Chicago, North Shore & Milwaukee interurban connected to the north side elevated at Howard. The bypass tracks were used by the Chicago Elevated to give service on the Niles Center "L" line to Skokie-Dempster and give access to the elevated's new shops at Skokie. The north-main was just recently elevated to a four-track concrete embankment replacing a two-track surface operation. It would take forty years for the elevateds to close a two-block two-track bottleneck at Wilson. Twelve years would pass before the city had the next expansion called the Initial Subway Project in 1938 featuring the first flying junctions.

[chicagopcclcar]

By 1910, the steel superstructure had been built and no more steel "L" would be added. In the 1920s the north-side main would be elevated to the concrete embankment that is so in need  of repair today. Then, in late 1938, the city finally moved ahead with plans for the Initial Subway program and construction began the next year. The subway plans called for three flyover junctions, easily done with the subway tubes coming up in between the existing tracks.  Further the plans included future flyovers for new routes, one at 13th St. and one at Lake & Milwaukee. But by 1960, the junctions were no longer used except for non-revenue service.

 

The Initial Subway flying junction at Armitage with the subway coming up in-between the four main tracks made for a short stretch with six tracks.  This photo was taken at the time when 6000s were the vogue.  Note the high standard signal posts.  CTA photo.