27 November 2016

What Level Boarding?

Caltrain disagrees with itself regarding which exact platform height to adopt for level boarding. Is it 50 inches or is it 25 inches? You be the judge. Consider the evidence:

Exhibit A: the Electric Multiple Unit conformed contract documents specify that the new level boarding platform height will be 50 inches:
Section Future Level Boarding 
CHSRA trains will run over the same alignment and stop at some of the same stations as JPB trains. The bi-level EMU must therefore have the same interface with the infrastructure as the future High Speed Rail cars, including clearance envelope, and platform boarding height. 
JPB plans to raise platform heights to approximately 50.5-50.75” ATOR (to interface with a vehicle threshold height of 51” ATOR), initially at San Francisco, Millbrae, and San Jose stations. Other station platforms on the JPB system may ultimately be raised to the same level. These requirements will likely require two sets of doors – one at high level and one at a lower level. 
To facilitate the scenario where all platforms are raised to the ~50.5” ATOR level, it must be possible for JPB to easily de-activate the lower level doors and add additional passenger seating in the lower level vestibule area. 
Section 3.3.3 Threshold Height / Platform Interface 
EMUs shall be compatible with JPB’s existing platform height (8 inches ATOR) and existing mini-highs (22 inches ATOR). In addition, EMUs must be compatible with JPB’s future level boarding platform height of approximately 50.5 to 50.75 inches  ATOR.   Each car shall be capable of serving both platform heights during the transition from the existing platform height to the future platform height.

Exhibit B: slides from a November 22, 2016 study session of the Mountain View Transit Center master plan, held to solicit input from the city council. In this document, we find out on page 14 that Caltrain plans to adopt a new level boarding platform height of 25 inches:
Design platforms for future level boarding operations, which will begin after the Caltrain fleet is converted from diesel to electric trains. Level boarding at a 25” height (versus the current 8” height) will shorten boarding time for all passengers and meet Americans with Disabilities Act requirements. 

Exhibit Cslides from an October 18, 2016 meeting of the Citizen Working Group advising San Francisco's RAB (Railyard Alternatives and I-280 Boulevard) feasibility study. On slide 11, we learn that Caltrain plans to adopt not one, but two level boarding platform heights. Platforms at 4th/King will be rebuilt to 25 inches, while platforms at Transbay will be built to 50 inches:
For 4th/King it is likely that Caltrain and HSR will operate at different platform heights 
• HSR will operate at 50-inches, Caltrain at 8-inches top of Rail (TOR). Therefore, there will be dedicated platforms for Caltrain and HSR at 4th/King 
Caltrain may change height of their platforms at some time to 25-inches from TOR but still will be different than HSR 
All platforms at TTC to be constructed at 50-inches. Caltrain will use 2nd set of doors at TTC and utilize any platform/track at TTC
This sort of inconsistency would be amusing if level boarding wasn't the most important modernization step that Caltrain must take after the electrification program is completed... and if the EMUs that Caltrain just ordered from Stadler could actually serve a 25" high platform.

The Stadler EMUs won't work with 25 inch platforms

Barring a contract change order and significant technical modifications, the EMUs as specified by Caltrain and as recently ordered from Stadler will not be capable of boarding or alighting passengers at a 25 inch platform.

First, there's the little issue that the floor height of the lower level of the new EMU was not specified in Caltrain's contractual documents. Stadler went with the standard 22" (550 mm) above the rail, according to their specs. Stepping down from a 25" platform into a 22" rail vehicle is frowned upon by regulators. But leave that aside and imagine the trains actually had a 25" floor level that matched a 25" platform.

Unless every single Caltrain platform were to be raised overnight from 8" to 25", a logistical feat that is exceedingly unlikely to be within Caltrain's financial means or capital project planning ability, the conversion to 25" level boarding will necessarily entail a transition period during which EMUs will serve an evolving mix of 8" and 25" platforms. This has technical implications described in the EMU contract documents:
For compatibility with the existing platform height, vehicles will require an intermediate step between the platform height and the lower level boarding threshold height, at approximately 16 inches ATOR.  This intermediate step must be either removable or retractable to support conversion to a high-door-only modification once all JPB platforms have been raised to 50.5 to 50.75”. The vertical face of this intermediate step will be located at approximately 61 inches from car centerline. In addition, a ramp or bridge plate must be provided to interface with JPB’s current mini-high platforms to load wheelchair passengers.  The ramp or bridge plate must comply with 49 CFR 38.95. The entire platform interface system must also be usable during the transition from the current platform height to the level boarding platform height. 
This "intermediate step" is identical to the step arrangement currently found on Caltrain's Bombardier bilevel cars. As long as the intermediate step is present (at 16 inches above top of rail and 61 inches from car center line), here's what the situation looks like at a "level boarding" 25 inch platform, during the transition period:

This is a fatal flaw. A level boarding solution must be structurally and operationally feasible, which this 9" deep by 16" wide gap is not.  This is not a simple matter of welding some plates over the step wells, since the intermediate step would remain in use throughout the transition period, likely several years.

The end goal must be unassisted level boarding at every station, fully compliant with the ADA gap specification of 49 CFR 38.93(d)(1).  Manually operated bridge plates are not okay; conductor-assisted level boarding won't cut it for a punctual and reliable blended system where HSR and Caltrain must share primarily two tracks.  This means Caltrain should either drop any talk of 25" platforms, or modify the EMU contract post haste with the same retractable bridge plates at the low doors as will be fitted to the 50" high doors.

Level boarding requires a carefully engineered solution and a crisp strategic plan for how to get there. The documents cited above suggest that Caltrain still needs to get it together.

20 September 2016

EMU Brochure

Credit: Stadler Rail Group
This week is InnoTrans 2016, the world's biggest rail industry trade show, held in Berlin, Germany. Stadler has a big presence there, and rolled out an updated website and downloadable brochures. Among them is a preliminary brochure for Caltrain's new KISS EMU, affording the first public glimpse into design details of Caltrain's new fleet.

Key Specs

The Stadler KISS (recently re-branded KISS160) as configured for Caltrain is a high-performance train that will have no issues sharing the corridor with high-speed rail.
  • Power: 6000 kW (8000+ hp)
  • Acceleration: 1 m/s2 from 540 kN (implying a loaded mass of 540 metric tons)
  • Braking: rated at 8000 kW, with most of the energy fed back into the electric grid
  • Vehicle width: 3 meters (comfortably inside US loading gauge)
  • Maximum speed: 110 mph
  • Straight sides, taking full advantage of US loading gauge, unlike European KISS
Train Layout

The six-car EMU shown in the brochure features dual boarding height doors throughout, to share platforms with high-speed rail and to enable Caltrain to transition gradually to gap-free level boarding, to cut down dwell times for the blended system.  The train consists of the following:

ParameterCar 1Car 2Car 3Car 4Car 5Car 6Total
Car typeCabMiddleMiddleMiddleMiddleCab-
Number of powered axles24040212
Seats, lower level3823638638149
Seats, upper level525260526052328
Seats, intermediate level10+21010+161010+1610+296
Seats, total102859210092102573
Bike spaces--40-40-80

As delivered, the upper level boarding doors are sealed and 5 seats are configured longitudinally in each vestibule on the intermediate level, accounting for 10 seats per car. These seats will be temporarily removed during the transition to level boarding with high platforms (when both sets of doors must be cleared of seats), diminishing seating capacity by roughly 10%. Once Caltrain achieves 100% level boarding, that seating can be restored on the lower level of each car.

The layout for all six cars can be viewed by zooming into the original PDF brochure, or more conveniently as individual graphics extracted below.


The seating diagrams reveal that the ADA bathroom displaces 15 seats.

Interestingly, the Stadler diagrams show two wheelchair spaces on the lower level of every car, which appears to imply that ADA wheelchair lifts would be provided in every car to cross between the lower and intermediate levels of each car.

Future Capacity

Caltrain's order from Stadler includes options for another 96 cars, which are planned to be exercised to expand the fleet to 24 trains and lengthen all trains to 8 cars or about 200 m long.

With the seating layout and train car dimensions defined, it is possible to predict the seating capacity of an 8-car train. The basic 6-car train already has all the traction equipment, so the two extra cars would likely be trailer cars similar to cars 3 and 5 above, except without the bike storage area on the lower level. Each of these extra cars would have 60 seats on the upper level, 46 seats on the lower level, and 26 seats on the intermediate level, for a total of 264 added seats. This would bring each train's ultimate capacity to 837 seats and 80 bikes, with plenty of additional space for standees.

31 July 2016

Future Proofing Hillsdale

The next big grade separation project on the peninsula rail corridor will be at 25th Ave in San Mateo, a logical next step in the decades-long process to grade separate the corridor.  This grade separation will establish a 6.5-mile stretch of 100% grade separated right of way, laying the groundwork for a future four-track mid-line overtake facility that will allow express trains to overtake slower commuter trains under the "blended system" jointly planned by Caltrain and the HSR authority.

Preliminary rendering of new
Hillsdale station with island platform
The latest plans presented to the Caltrain board of directors show a split-grade elevated solution, built sufficiently wide for four tracks but initially only fitted with two tracks spaced on approximately 48-foot centers.  The Hillsdale station is moved north by a quarter mile to straddle 28th Ave, and fitted with a central island platform sized approximately 36 x 700 feet and built 8 inches above the rails.

Vertical circulation to this island platform is provided at the north end (two stairways connecting to the sidewalks on each side of the new 28th Ave underpass) and the south end of the station (a new pedestrian tunnel with one stairway and one wheelchair ramp).  In cross section, the new Hillsdale might look like this:

Of course, the accelerated schedule for its completion is closely linked to electrification, so quite soon thereafter it might look like this, with mixed diesel and EMU service.  Note that per Caltrain plans, the overhead contact system is 22 feet above the rails. plenty to clear even the tallest freight cars.
It's not too difficult to guess what happens when the blended system overtake tracks are built: the new platform and all associated vertical circulation (stairs and ramp) will be demolished, to be replaced by a pair of new express tracks right down the middle of the corridor.  A first phase of this "New New Hillsdale" station would like this, hopefully with level boarding platforms.  Note the new portal configuration of the overhead electrification, to span across four tracks and two platforms without placing poles close to the edge of the new platforms:
After demolition of the "New Hillsdale" island platform, the original 48-foot track centers allow for two additional overtake tracks and a central fence (track spacing 15 + 18 + 15 feet) to prevent passengers from crossing between the two new side platforms of the "New New Hillsdale."  Including stairs, the "New New" station is 106 feet wide and looks as much as possible like any station on Amtrak's Northeast Corridor.  It could almost be mistaken for Princeton Junction:
While it's a fine idea to build the new grade separation sufficiently wide for four tracks, demolishing the "New Hillsdale" station only to replace it so soon with a "New New Hillsdale" seems terribly wasteful. Perhaps this is another case of "why build it right when you can build it twice?" Surely there is a better way.

Rebuilding Hillsdale Once and for All

There's a much better way to build the New Hillsdale once and for all.  It initially looks like this:
Note the central island platform is a full-height level boarding platform, disguised for now as an 8-inch platform by raising the track bed by 51 - 8 = 43 inches using a thicker-than-usual layer of ballast. The final footprint of this station, which will ultimately have the HSR overtake tracks on the outside, is less than 100 feet wide at the platform. The footprint will never change; all the concrete has been poured and not another cubic yard is needed in the future. Soon after electrification, mixed EMU and diesel service would look like this:
The overhead contact system is built in its final configuration 22 feet above the eventual height of the tracks; because the tracks are raised by 43 inches, the vertical clearance is temporarily reduced to 18' 5" which still safely accommodates Plate F freight cars, the tallest that have historically been used in this part of the corridor.  Therefore, there is no constraint to freight service.  This electrification will never change, with all the portals in their final configuration.

When all the diesels are gone and it's time to transition to level boarding, a track maintenance project takes place over a weekend.  43 inches of ballast are removed from under the tracks, using standard track maintenance machines.  The rails are never even disconnected.  (Not to be too flippant, this is still a major track maintenance operation that would require sophisticated planning and modern high-capacity machinery; but it is certainly within the realm of what Caltrain has done before.) Minor lateral adjustments are made to track and overhead contact system alignment, yielding this for the Monday morning rush:
Not a single cubic yard of concrete is required either to convert to level boarding, or to add the overtake tracks once HSR service begins on the peninsula.  The final blended system configuration is ultimately this:
Built once, and built right!

That FSSF Thing

Placing the express overtake tracks on the outside, in a fast-slow-slow-fast or FSSF configuration, as opposed to the traditional slow-fast-fast-slow or SFFS configuration inspired by road design, is a key architectural decision for the blended system.  The forces of traditionalism will argue strongly for SFFS because that's how it's "always" done, yielding nice straight express tracks down the middle of the corridor-- but clear exceptions to this "rule" exist, with examples of FSSF corridors in these videos from Sweden (with 125 mph express trains!) and Australia.

The fatal operational flaw of traditional SFFS corridors is that when a track must be taken out of service, either accidentally or intentionally for maintenance, commuter trains either must cut across the express tracks (fouling express traffic) to reach the opposite platform, or use super awkward bridge plates to board from the fouled express track.  In contrast, an FSSF island platform is operationally flexible: the train simply crosses over to the opposite side of the island, without ever getting in the way of express traffic.  For the peninsula "blended system" where Caltrain and HSR share the corridor, the operational headaches of SFFS could prove unworkable in the long run as the rail corridor is maintained.

One argument systematically trotted out against FSSF is this: wowing express trains around the outside of every island platform will make for a slalom "barf ride" that will give HSR passengers motion sickness, if not downright whiplash.  This argument intuitively rings true, but turns out to be patently false when you run the numbers.  In reality, an express train blasting around the Hillsdale island platform at 125 mph will do so on curves with a radius greater than four miles, requiring just 2 inches of superelevation to be rendered imperceptible to passengers.

Download FSSF island platform plans
for every station on the Caltrain corridor
(3.3 MB PDF, see page 9 for Hillsdale)
Another argument leveled against FSSF is that the island platform arrangement requires additional right of way compared to a traditional SFFS outside platform arrangement.  The footprint of a FSSF station can be made nearly as compact as a SFFS station, especially if the central island platform (shown in the above diagrams at 33 feet wide) is slightly tapered at its ends, yielding an imperceptibly curved platform that is for all practical engineering purposes the same thing as a tangent (straight) platform. In any case, the available right of way at the Hillsdale location is a generous 150 feet wide, making such footprint considerations moot.

The Takeaways
  • DON'T rebuilt infrastructure multiple times.
  • DO build it once and build it right, in its final configuration
  • DON'T build station platforms that are not compatible with level boarding, where this can be avoided.
  • DO create the Caltrain engineering standards for level boarding.
  • DO build the new Hillsdale station with a level boarding platform, years before the transition to level boarding occurs, by temporarily raising the track bed to make the platform only 8" tall.
  • DO build the new Hillsdale station as an island platform, even after high-speed overtake tracks are added
  • DO put the high speed tracks on the outside, in the FSSF configuration, for operational flexibility.

25 July 2016

Steaming Pile of CBOSS

CBOSS, the Communications Based Overlay Signal System, is a Positive Train Control (PTC) system being developed by Caltrain to prevent human error from killing or maiming passengers or rail workers.  It is a deeply troubled project.  Caltrain recently requested a peer review of the project from APTA, the American Public Transportation Association, whose subject matter experts were given access to personnel and documents.

Download the final report from the peer review here (500 kB PDF).

It's fair to say our worst fears have come true:
  • the project manager does not have the requisite technical experience
  • there is no project schedule, and October 2016 is just another month on the calendar
  • inter-operability requirements and test methods are not defined or agreed upon
  • configuration management is not just out of control, but completely lacking as a process
  • software and network security is an afterthought
  • animosities between project management and the contractor are impeding the resolution of technical issues
  • operator training has not started, and the materials for such do not yet exist
  • weekly top-level status meetings between Caltrain management, the program management consultant, and the contractor had not been occurring
The list of documents reviewed by the panel in Appendix C would make a juicy FOIA request.

A little bird overheard some discussions that do not appear in the APTA final report, because the report is intended to provide only constructive criticism to help Caltrain out of this mess.  It's even uglier than you could have imagined:
  • Parsons Transportation Group (PTG), Caltrain's prime contractor, does not have the right skills mix to manage complex system integration on 13 different subcontracts
  • PTG is fearful that the commercial terms of the CBOSS contract expose them to legal action by Caltrain, contributing to the lack of transparency
  • Subcontractor General Electric (now Alstom) discovered that simply re-using the existing ITCS product wasn't going to work.  The inter-operable version of the product is incurring massive increases of scope that were not accounted for in the original contract
  • Because of the extent of the changes made to ITCS, the FRA is requiring the same certification and type approval process as for a new PTC system, undermining Caltrain's claim to reusing an off-the-shelf technology
  • The FRA has taken the position that Caltrain is really installing two PTC systems, requiring full testing of both I-ITCS and IETMS (the system that will be used by Union Pacific freight trains on the peninsula corridor)
  • Inter-operability means not only allowing IETMS equipment to operate in CBOSS territory, but also allowing CBOSS equipment to operate in IETMS territory, something that Union Pacific has been concerned about testing thoroughly
  • Poor coordination for accessing an operating railroad for system installation and testing has been and continues to be a bottleneck
  • Additional funding is going to be needed, but nobody knows how much more
  • A change of contract operator (currently Transit America Services, Inc, soon coming up for re-bid) would introduce significant program execution risk
  • Getting all the CBOSS-equipped trains into revenue service could take up to 5 months
The already egregious sum of $231 million to cover a measly 51 route-miles with PTC is about to increase significantly, something you would never guess from the latest CBOSS update provided to Caltrain's laissez-faire board of directors.
Fast forwarding to whatever year it eventually takes place, the RSD (Revenue Service Demonstration) will consist of flipping the "on" switch and transforming rush hour into an epic cascade of software glitches reminiscent of the 1998 MUNI Meltdown.  On that day, we will all know that this CBOSS turkey has finally come home to roost, as was foretold way back in 2009.

10 July 2016

The Capacity Problem

These days, Caltrain is breaking a ridership record nearly every month.  Rush hour trains are running with standing-room-only crush loads, measured by Caltrain's statistics as a percentage of seating capacity.  The most recent ridership counts (tallied during the low-ridership season in the first quarter of 2016) showed several trains running at 125% of seated capacity, even after the addition of a sixth car.  Capacity, or the lack of it, is becoming a problem and Caltrain will need to do more about it before 2020.

A montage of what a Caltrain EMU
by Stadler might look like,
based on a photo by Yevgeny Gromov
The recent award of electrification contracts, including an order for sixteen new six-car EMU trains from rail vehicle manufacturer Stadler, has brought this issue to the forefront.  Caltrain's Chief Operating Officer for Rail, Michelle Bouchard, had to concede in front of the Caltrain board of directors that the new EMUs would initially have a lower seat count than the diesel trains they will replace. The argument was that increased capacity could be achieved by increasing train frequency from 5 to 6 trains per peak hour per direction, and ultimately by lengthening the EMUs from 6 cars to 8 cars, something that can be done to an EMU without loss of performance or track capacity, unlike a diesel train.

Here are some thoughts about the capacity problem.

Capacity is measured in people, not seats.  Measuring passenger load factors as a percentage of seated capacity works well for airplanes, but doesn't quite do the trick for a transportation mode where passengers routinely stand.  The design of a train, including the number of seats, the interior layout, and accommodations for standees (handrails, poles, straps, etc.) has an enormous effect on the level of comfort experienced by passengers when the car operates at "125% seated capacity."  In rail vehicle A, filled with seats and with few places to stand, 125% feels uncomfortably crowded.  In rail vehicle B, with a lower seat count and large areas where passengers can comfortably stand, 125% of seated capacity feels just fine. A better metric of the true capacity of a rail vehicle is the number of seats plus some number of standees per unit of usable floor area (typically 4 standees per square meter); with such a metric, "100% capacity" feels like the same crowding regardless of train design.

Load factors over 100% seated capacity are desirable.  While this may be news to the person crushed between two sweaty people in the vestibule of a rush hour train, sizing the train fleet so that everyone can get a seat during the peak leads to a lot of empty seats running around the system or idling in yards during off-peak hours. This can be mitigated by changing the length of train consists (like BART), but unless trains are designed for this to begin with, it can't be done in daily practice.  Caltrain's new fleet of EMUs will not be easily reconfigurable unless two EMUs are coupled together; plans for this are not evident in the train configurations discussed in the EMU Request for Proposals (6 cars and 8 cars).  With fixed train consists, there is necessarily a sweet spot where a balance is achieved between two undesirable conditions: too many bums and not enough seats during the peak, and too many seats and not enough bums off-peak.  That sweet spot will mean peak load factors should very well be over 100% when measured as a fraction of seating capacity.

LIRR M-7 rail car with 5-abreast,
by Lexcie via Wikimedia Commons
Middle seats are seats, too.  The idea of 3+2 seating (five abreast) is usually batted away with a summary argument that passengers don't like middle seats, but it undeniably results in more seating capacity.  The question is, do passengers dislike middle seats more than they dislike standing? Commuter railroads on the East Coast seem to know the answer: the Long Island Rail Road M-7, the Metro North M-8, and the SEPTA Silverliner V, (to cite only the most modern examples) all feature 3+2 seating areas.  If providing seated capacity is so important, and if load factors are going to be measured as a percentage of seated capacity, then that middle seat is worth an easy 25% additional capacity.  The Caltrain EMU contract could be changed to require 3+2 seating; Stadler has already built a 3+2 bi-level EMU for a Russian client.

Fewer seats can actually increase passenger capacity.  If Caltrain stays with 2+2 seating and a lower seat count, the additional space for standees can provide greater passenger capacity if standees are properly accommodated.  The new EMUs should be configured with poles, handrails, grab handles or straps as necessary to allow standees to travel comfortably when no seats are available.  During the platform height transition period when Caltrain will be operating dual boarding heights (two sets of doors), the number of seats will temporarily drop after seats are removed from the high door boarding vestibules.  This may increase the load factor when measured as a percentage of seated capacity, but it will actually increase passenger capacity by opening up more room for standees.  Comfort may suffer, but only temporarily.

Caltrain should find a way to buy 8 car trains right away.  If some trains are already running at 125% seated capacity in 2016 during the winter low season, they are probably running at 150% seated capacity during the summer.  Seasonal load factor will go even higher if ridership continues to increase between now and 2020 when the new EMUs arrive.  By then, even with the entire Caltrain diesel fleet at six cars per train, the system will likely be bursting at the seams.  The step change in service quality thanks to the new EMU fleet will trigger another ridership increase.  Taking into consideration those three factors (high season peak, continued ridership escalation and better EMU service), it seems likely that six-car EMUs will be overcrowded from day one.  If Caltrain can scrape together another ~$150 million (another 7% of the total tab for modernization) to exercise an option on the Stadler contract, all EMUs can enter service in 2020 as 8-car trains.  Short platforms can be dealt with by prohibiting boarding and alighting from the front or rear cars at the few stations that cannot berth a 200-meter train.  An eight-car Stadler KISS with 2+2 seating will accommodate about 750 seated passengers and another 1000 standees.

10 June 2016

EIR Scoping Comments

The following are scoping comments regarding the San Francisco to San Jose project section of California's high-speed rail system.

System-wide Level Boarding: the blended system is a compromise, less than ideal for HSR and Caltrain.  The successful mixing of local and long distance express service on "primarily two tracks" will require the utmost coordination and reliability in order to satisfy the expectations of commuters and statewide travelers.  The key to punctual operation is to ensure that station dwell times are short and predictable, something that cannot be achieved with today's 8-inch-above-rail Caltrain platforms. The EIR should study a system-wide conversion to level boarding, as facilitated by Caltrain's procurement of dual boarding height EMUs.  Level boarding does two important things for HSR: it ensures that Caltrain commuter trains get out of the way of HSR in timely and reliable fashion, and increases the average speed of Caltrain services, unlocking additional track capacity.  The frequent service and punctuality that travelers will expect of HSR cannot be achieved without level boarding.

Fast-Slow-Slow-Fast Overtake Sections: four-track overtake sections should be configured with overtaking tracks on the outside and slow tracks in the middle (fast-slow-slow-fast) with central island platforms for Caltrain.  The major advantage of this configuration is to allow Caltrain to single-track as needed during service disruptions without fouling the express tracks.  While the track centers will need to shift outwards to make space for island platforms, the resulting curves can be built with very large radii and very low superelevation, with no impact to passenger comfort.  The station footprint requirements for fast-slow-slow-fast are minimal due to one island platform being narrower than two side platforms.  Examples of the fast-slow-slow-fast configuration exist in Sweden and Australia.  Given the operational advantages of this configuration, the EIR should study it as an alternative for any proposed four-track overtake sections.

Grade Separations: should any new grade separations be contemplated as part of the blended system, these should be engineered "not to preclude" the future addition of a third and fourth track. The peninsula corridor right-of-way is so generously sized that building new two-track-only infrastructure is short-sighted and potentially wasteful.  Even if grade separations are initially built for two tracks, the EIR should study full-sized bridge abutments and retaining walls as needed to support future expansion, even if such expansion is not part of the project scope.

Dumbarton Connection: some form of rail service in the Dumbarton corridor has been studied for decades and is likely to be implemented sometime in the next half-century, given regional development and transportation pressures.  Any changes to Dumbarton Junction that might be studied in the EIR should be engineered "not to preclude" a future seamless Dumbarton rail corridor connection, including a grade-separated flying junction for at least the southbound track.  While this may carry the political appearance of leaving the door open to HSR via Dumbarton and Altamont Pass, such political considerations should not be used as an excuse to sabotage the possibility of an efficiently designed rail junction with the Dumbarton corridor.

Mid-Peninsula HSR Stop: the EIR should study the possibility of a mid-peninsula HSR stop located in Redwood City.  With a common platform interface standard shared by HSR and Caltrain, the impacts could be quite minimal.  In the long term, a four-platform-track elevated (i.e. grade-separated) station should be considered for this location.

Platform Track Speeds: high-speed express trains currently run past Caltrain platforms at a maximum speed of 79 mph, with only a painted yellow line to warn people on the platform to stand clear.  Electric express trains operating at 110 mph (on primarily two tracks, and hence running past Caltrain platforms) are both faster and quieter, and have a higher chance of startling people standing on the platform, possibly causing them to lose their balance and fall towards the passing train.  The EIR should account for the impacts of constructing wider Caltrain platforms with ample clearance to stand clear of passing trains, with appropriate visual and aural warnings.

Hold Out Rule: the EIR should include a study of the impacts of modifying the few remaining stations (South San Francisco, Broadway, Atherton and College Park) that still have narrow at-grade center platforms, where no trains may move through the station while another train is stopped.  The hold-out rule is a disruptive and antiquated operational constraint that is contrary to the needs of a fast, flexible and high-capacity blended rail system; the cost of eliminating this constraint is minuscule in relation to the overall investment being contemplated.

Blended System Southern Boundary: San Jose Diridon, while an important HSR stop, is not a natural terminus for Caltrain services.  Large population densities in the vicinity of the Tamien, Capitol and Blossom Hill stops that are currently located on the "Gilroy Extension" of Caltrain should be served more regularly.  Moving the southern boundary of the blended system beyond Tamien to Blossom Hill would not only meet latent commuter demand on the congested 101 corridor, but also free up scarce platform capacity at San Jose Diridon by avoiding the need to turn any trains there.  For this reason, the EIR should consider the idea of terminating Caltrain service at Blossom Hill.

CEMOF Alignment: Caltrain's Central Equipment Maintenance and Operations Facility (CEMOF) was constructed with a double reverse curve that severely limits train speeds near San Jose, if an at-grade solution is contemplated.  Because achieving fast San Francisco - San Jose times is important to HSR's compliance with the terms of the HSR bond act, the EIR should study the possibility of reconfiguring the track layout of CEMOF, moving the main tracks from the east side of the facility (the slow double reverse curve) to the west side of the facility (a faster alignment, with only one shallow curve).  This would effectively exchange CEMOF yard tracks 8 and 9 with MT-2 and MT-3.  Personnel, equipment and materials can enter the facility through a tunnel under the main tracks, as is already done for access from the east.

Newhall Yard: VTA owns a large former UPRR freight yard in Santa Clara, currently slated to be used as a future maintenance facility for the BART to Silicon Valley project.  In the event that the BART Phase II project is value-engineered to terminate at San Jose Diridon (without a redundant and duplicative extension that parallels the blended system to Santa Clara, and with vehicle maintenance requirements met by BART's amply sized Hayward Maintenance Complex), the EIR should study the possibility of using Newhall Yard as a maintenance facility for HSR.

07 May 2016

Caltrain Has a Dwell Time Problem

Actually, Caltrain has two dwell time problems. The first is that station dwell times are too long, and the second is that station dwell times are too unpredictable.  Both of these problems will prove fatal to the blending of Caltrain and HSR services on "primarily two tracks."

To help visualize why, let's use position-versus-time string diagrams, often discussed on this blog.  Imagine trains following each other on a single track that runs from San Jose to San Francisco (ignore the other direction for now).  This red line is a local train making a lot of stops.  It leaves San Jose, and a while later arrives in San Francisco.  If you looked really closely you might see the individual station dwells, small horizontal kinks that occur whenever the train is stationary and time passes, but when you squint, it looks pretty much like this:
Every once in a while, this local train comes to a station where Jane, a wheelchair user bound for San Francisco, would like to board.  Because we don't have level boarding, getting Jane on board the train involves manually deploying lifts or ramps to ascend the several steps from the platform into the train.  Conductors must help Jane through the mechanics of the boarding process, which can easily take several minutes but feels like an eternity, even for Jane.  Timetable planners allow for riders like Jane by making sure that no other trains are scheduled right behind each other, to absorb these randomly occurring super long dwells without causing a train traffic jam.  They call it padding.  Here's what padding looks like, in pink:
This being a blended system on "primarily two tracks," we've got express trains and even high-speed trains using the same track as Jane's local.  A faster train looks like this blue line:
The blue line is steeper because the express train can cover the same distance from San Jose to San Francisco in much less time.  Here comes the express behind the local:
The timetable planners don't want the express to be delayed.  That's why they left a big gap between the trains, giving the local a good head start out of San Jose so that the express won't catch up to it before San Francisco.  Alternately, here is the local departing San Jose right behind the express:
Once again, a big gap opens up behind the express because the local is so much slower to arrive in San Francisco.  Now it's rush hour, and this is what "blending" soon looks like (not to scale):
In one hour, six trains can arrive in San Francisco.  Our string diagram is full of gaps, which means we are making very poor use of the capacity of our single track.  How do you fix this?

First, you electrify Caltrain.  While this isn't cheap, one of the main advantages of electrification is that EMUs start and stop much more quickly, so that on average, a local can get to San Francisco several minutes sooner while still making the same station stops.  The local will have a higher average speed than it did before.  Compare:
See how the new EMU local train shows up as a steeper line?  That's because it spends less time moving between stations.  (Note to Atherton: electrification is not just an emissions thing.  Tier IV diesel trains can't pull off this neat trick like an EMU can.)  Now this is what the "blended" rush hour looks like:
If you compare it carefully to what we had before, we can now fit eight trains in the span of one hour, instead of six, because those dreaded gaps are shorter.  By increasing the average speed of the locals, we were able to squeeze in more trains (and more passenger capacity).  Caltrain seems content to declare victory and live like this happily ever after.  This is what they envision as the "blended system".  Whenever Jane decides to ride the train, the pink padding still ensures that following trains aren't delayed too badly.

It's better, but still kind of mediocre.  Especially for Jane.

What if the local train could spend less time standing still at each station?  Dwell time can be reduced by level boarding, a step-free and gap-free configuration where you simply walk on or walk off the train, just like when you ride BART.  For a given number of passengers getting on and off the train, level boarding shaves off about 1/3 of the station dwell time since they can all shuffle on and off more quickly and seamlessly.  The magic of reducing dwell times is that while the train's actual speed is no higher, it still gets to San Francisco sooner, because it saved a few seconds during each station stop.  A few seconds here, a few seconds there, and pretty soon you're talking several minutes.  The average speed went up without the actual speed increasing!  The string for an EMU local with level boarding now looks like this:
If the local arrived in San Francisco ten minutes earlier thanks to electrifying Caltrain, it can arrive another five minutes earlier than that by having level boarding at all stations.  Electrification saves time between station stops, and level boarding saves time during station stops.  The two work together as perfect complements to each other.

The diagram above is actually wrong, and here's the second amazing thing about level boarding: Jane can get on and off the train like everybody else.  Not only does this give Jane the dignity and equal treatment that she deserves, but it saves everybody else the grief of those randomly occurring Jane delays.  Because dwell times are now predictable, timetable planners can get rid of the padding they applied in case Jane wanted to ride before.  Like this:
If you like probability distributions, here is the effect of level boarding on the probability distribution of dwell time:
Caltrain commissioned a study of station dwell times, which found that across a sample of 5149 station dwell observations, the median duration from wheel stop to wheel start was 49 seconds.  The median excludes abnormally long dwells, such as those occurring when Jane wants to ride.  The average dwell time does account for Jane and is 58 seconds, practically an eternity.  That was back in 2010.  Today, with the system bursting at the seams, average dwells are getting so long that the timetable was recently adjusted to make chronically late trains into slower on-time trains.  With level boarding, typical dwell times could easily be cut to 30 seconds.

Level boarding really improves the situation for rush hour:
We're really cooking now.  We can squeeze 12 trains through in one hour on the same track.  That represents a massive capacity increase, with the combined effect of reduced and predictable dwell times providing a similar benefit as electrification alone did.

Caltrain staff just doesn't seem to get this, and they are certainly not helping their board of directors understand the issue. They think of level boarding as primarily an optional comfort feature. Here is their view of level boarding, from a recent board meeting quarterly update:

First of all, they don't even call it level boarding. Dual doors!  What a pain!  Requested by interloping stakeholders, or imposed by those annoying HSR people!  Ew, it's so complicated!  It costs $30 million to equip the new fleet!  It's almost as if they are disowning the very idea of level boarding, and reluctantly trying "not to preclude" some unspecified future decision because this stuff is just too hard to think about.  Presented this way, you couldn't blame the board or the public for thinking this is a stupid idea.  Where's the upside?

The upside is this: dual doors are the only realistic path for Caltrain to achieve level boarding, and level boarding is the only way that the blended system can work on "primarily two tracks."

This issue cannot be taken lightly, because the next opportunity to start a Caltrain conversion to level boarding will not occur until 2050, when the new fleet reaches the end of its useful life.  That's because the new fleet, as about to be ordered, cannot provide level boarding at a platform height of 25 inches.  The entire system would have to be shut down for the trains to be modified and all platforms to be rebuilt at that height.  So, doing nothing today and blindly kicking the can down the road until 2050 is not an option.  A prudent and strategic $0.03 billion down payment for a gradual transition to level boarding is minuscule as a fraction of the $2.2 billion modernization budget, and unlocks great potential for quicker and more punctual commutes as soon as the next decade.

Dual doors are a customization that amounts to less than 5% of the price tag for new trains ($30 million out of $648 million bid price).  They can hardly be used as an excuse for the massive increase in the cost of Caltrain modernization.  They will help to address Caltrain's dwell time problem.

Caltrain has a dwell time problem.  The first step is for everyone (staff, board and public) to understand it.

13 February 2016

Train Control Update

There have been two recent and important developments in the area of train control systems, the safety systems known in U.S. parlance as "Positive Train Control" or PTC.  Both of them have a direct impact on the future of the peninsula rail corridor.

CBOSS Goes Sideways

Caltrain's CBOSS project, criticized for years on this blog, is in ever deeper trouble.  According to Caltrain's latest project update, the $231 million previously allocated for this project are nearly spent, but the project is way behind schedule and struggling in the most perilous and delay-prone phase of all: testing of the integrated system.

Not Ready for FRA
Testing is where it all finally comes together, not in the carefully controlled environment of a lab test bench, but in the real world with all its ugly imperfections, annoying glitches, and external influences.  In each segment of the railroad, three things have to happen in sequence: (1) everything has to be fiddled with until it works; (2) when everything works, a dry-run of the official acceptance test, known as "Pilot Testing," is performed; and (3) the system is formally accepted after passing the official FRA-witnessed test of all its functions.  Caltrain's project is stuck in the "fiddle with it until it works" phase, helpfully diagrammed as an infinite loop in the test flow diagram at right, extracted from a CBOSS Verification, Testing and Inspection Plan filed with the FRA.  This is where the schedule and budget are blowing up, with Caltrain's next step described as "Complete Segment #3 Pilot Testing and FRA Witness Testing," coming as soon as they are "Ready for FRA," whenever that may actually be.

Caltrain's update mentions "software release delays" relating to the I-ITCS product that CBOSS is based on.  There are worrying signs that I-ITCS may become a technological dead end: the company that makes it, GE Signalling, was recently acquired by French rail giant Alstom.  Alstom's mainline signaling product portfolio does not give it top billing.  Furthermore, the FRA process is described as being "in flux", meaning that the goal posts are moving.

What we have here is a classic foundering IT project, and it isn't clear if throwing more money at it (at a burn rate of about $50M/year) is going to save it.  With the federal PTC implementation deadline now pushed out to 2018, this is a good time to stop and re-assess the project before escalating the commitment.

HSR Buys Radio Spectrum

Meanwhile, the California HSR Authority is about to spend $50 million to secure the rights to a key chunk of radio frequency spectrum.  The frequency bands being purchased are 757-758 MHz and 787-788 MHz, not the usual 220 MHz band used for freight PTC systems.  Instead, the CHSRA has documented its intent to deploy ERTMS, an increasingly mature and proven train control standard that originated in Europe and is increasingly in worldwide use.  The two bands purchased for HSR are not sufficiently wide to deploy GSM-R, the obsolescent communications standard currently used as part of ERTMS.  It is more likely that California's deployment of ERTMS will use a more modern, secure and spectrum-efficient LTE communications layer, following the evolutionary path beyond GSM-R already being planned for ERTMS.

Connecting the Dots

Suppose the following conditions come to pass:
  1. CBOSS proves unworkable (increasingly likely)
  2. HSR shifts its focus to Northern California (possible)
  3. HSR finalizes plans for ERTMS as its high-speed train control standard (very likely)
  4. Due to construction delays, HSR needs new and productive ways to spend federal funds that expire by 2017 (possible)
Then an opportunity exists to deploy a train control pilot project on the peninsula rail corridor, using ERTMS with LTE communications in the 700 MHz band.  This scenario recognizes an important fact so far disregarded by Caltrain, that HSR will become by far the largest tenant railroad on the peninsula.  Ignoring this fact is an odd position to take for a railroad that hangs its future on "blending" with HSR.  Caltrain will surely dislike the idea, bleating about closer headways, crossing signal integration, station stop enforcement and other completely unproven bells and whistles--as they have since 2009--but events are now quite clearly bearing out the relative technological merits of ERTMS and CBOSS.  It's just sad that it took a quarter of a billion dollars to settle the question.

In the unforgiving world of system integration testing, reality always wins.

02 January 2016

Special Provision SP01040

Buried deep in the fine print of Caltrain's electrification Request For Proposals, Volume 3, Part C, Paragraph 1.04, you will encounter Special Provision SP01040.  It defines where and when the electrification contractor will be allowed access to Caltrain's tracks to perform the work of re-signaling and electrifying the railroad.  These are known as "work windows" and are tabulated at right, as extracted from the RFP.

What follows is an analysis of the far-reaching cost and schedule implications of Special Provision SP01040.

Temporal Windows

Special Provision SP01040 imposes the following time restrictions:
  • No work during weekday peak hours (6 - 10 AM and 4 - 8 PM)
  • No work on Tuesdays and Wednesdays overnight, for track maintenance
  • Only one track available mid-day, evenings and weekends
  • Two tracks will only be available in the early morning hours Friday - Tuesday.
The limits defined in SP01040 do not include time for sending crews and equipment to or from the work site, known in construction jargon as "mobilization" and "demobilization".  An hour is eaten away from the beginning and end of each work window for this purpose.

If you want to analyze a typical work week on an hour-by-hour basis, you can define six different track availability states.  Each state has associated to it an availability factor, which you can think of as how many tracks are available to perform productive work (i.e. re-signaling or constructing the overhead contact system).

Availability StateAvailability Factor
No access0
Mob/Demob for 1 track0
Mob/Demob for 2 tracks0
Single track available for work0.75
Mob/Demob for 2 tracks with 1 track already available1
Both tracks available for work2

During periods of mobilization or demobilization, the work window is technically open to the contractor, but no useful work can occur since crews are busy moving equipment and materials to/from the work site.  When a single track is available for work, trains passing on the other track will occasionally interrupt the work, which is why the availability factor is 0.75 rather than 1.  This typically accounts for 2 trains passing the work site every hour, causing work to cease for 15 minutes due to worker safety protocols.  When mobilizing both tracks for the contractor, these passing trains cease and the availability factor increases to 1.  The ideal situation is when both tracks are shut down and the contractor has full control of the work site.

Geographical Windows

The corridor has been divided into geographical segments, at least some of which must remain open at all times to allow northbound and southbound trains to meet and run past each other.  Each segment has a certain length (measured in route-miles).

SegmentLength (miles)
Segment #1, MP 0.3 - 8.0 (CP 4th to CP Sierra)7.7
Segment #2, MP 8.0 - 29.1 (CP Sierra to CP Alma)21.1
Segment #3, MP 29.1 - 44.5 (CP Alma to CP De La Cruz)14.8
Segment #4a, MP 44.5 - 47.5 (CP De La Cruz - CP Alameda)3.0
Segment #4b, MP 47.5 - 51.1 (CP Alameda - Tamien)3.6
Yard Facilities (4th & King, CEMOF, San Jose)3.0

Note that various yard facilities are assigned 3 route miles (6 track miles).

During the first phase of electrification, work may only occur in segments 2 and 4, with both tracks open in segments 1 and 3 to allow trains to meet.  Then, following an adjustment to the timetable, the second phase of the work will occur in segments 1 and 3, with both tracks open in segments 2 and 4 to allow trains to meet.  This allows Caltrain to maintain hourly service in both directions during mid-day, evening and weekend periods, single-tracking as needed around electrification work sites.

Labor Costs

Let us loosely define a unit of labor to perform electrification work on one mile of track for one hour (however many people that may actually take).  One labor unit is multiplied by the number of track miles and the number of hours to calculate a burn rate, or how much the labor will cost during any given period of time, assuming the contractor makes full use of the work windows.

We will assume that when both tracks are open, efficiencies can be realized so that only 1.5 labor units (rather than 2) are required to work on 1 route-mile (2 track-miles).  We can then assign a labor cost for each track availability state defined above:

Availability StateHourly Labor Rate
(per route mile)
No access0
Mob/Demob for 1 track1
Mob/Demob for 2 tracks1.5
Single track available for work1
Mob/Demob for 2 tracks with 1 track already available1.5
Both tracks available for work1.5

The work is performed by skilled union workers, whose hourly cost is not always the same.  While weekday work can be performed in shifts at no additional hourly expense, weekend work is another matter.  Depending on the union and the trade (the RFP contains hundreds of pages of union wage rate tables), weekend work can cost up to twice the rate of weekday work.  Let us assume overtime cost factors in as follows:

Day of WeekOvertime Factor
Monday - Friday1
Efficiency Metrics

Now let's pull all these assumptions together and come up with three metrics.
  1. The first metric is average track avaibility, measured in track-miles.  It measures how much of the railroad is available for actual productive electrification work, as opposed to shuffling workers and equipment or dodging out of the way of trains.  Average track availability is inversely proportional to how long it will take to complete the work.  If you double the amount of available track, the job can be done in half the number of weeks.  There are limits to this assumption, of course, but for sequential tasks requiring direct access to track, such as re-signaling and constructing the overhead contact system, this inverse relationship is quite reasonable.

    The way to compute average track availability is to assign each hour of the week a track availability state, based on the rules set out in SP01040.  Then, we multiply the availability factor (associated to that state) by the number of route-miles in that segment to calculate how many track-miles are available for work in that particular hour in that particular segment.  We can repeat this calculation for every hour of the week (24 x 7 = 168 hours) and for every segment.  Finally, we can add it all up and divide by the total number of hours in a week to figure how many miles of track are available on average.

    But it's not quite that simple.  Since the work is divided into two geographical phases, we must first add up the availability for segments 2 and 4 (Phase 1) and then separately add up the availability for segments 1 and 3 and the yards (Phase 2).  The average track availability for Phase 1 and Phase 2 is then averaged; this average is weighted by segment lengths to serve as a proxy for duration of each phase.
  2. The second metric is burn rate, measured in labor units per week.  It measures the rate at which money is spent on all the work, including not just actual productive electrification work but also the shuffling of workers and equipment and the dodging out of the way of trains.  This metric assumes that the contractor makes full use of the available windows, and that no additional hourly expenses are incurred outside of the work windows (e.g. due to the work not filling a full 8-hour union shift).

    The way to compute burn rate is to multiply the hourly labor rate (associated to each hour's track availability state) by the number of route-miles in that segment and the overtime factor for that particular day of the week, to calculate how many labor units are expended in that particular hour in that particular segment.  Once again, we need to be careful how we add up the labor for Phases 1 and 2, using the same partial sums and weighted averages as for track availability.
  3. The third metric is installation efficiency, measured in labor units per week per available track mile.  It measures how much of the labor is expended on actual productive electrification work, as opposed to unproductive tasks such as the shuffling of workers and equipment and the dodging out of the way of trains.  It serves a rough measure of the overall cost of tasks requiring access to the track, such as building the overhead contact system and re-signaling.  It is defined simply as burn rate divided by average track availability.  A lower number is better, indicating that a given length of track can be completed using less labor.
Four Scenarios

Armed with these metrics, we can analyze and compare a variety of electrification scenarios, including the baseline scenario specified in the RFP per Special Provision SP01040, and other scenarios of our choosing.

For the detailed calculations that support each scenario, or to explore your own scenarios and change any of the assumptions, you can download this Excel spreadsheet.
  1. Baseline Scenario: Let us scrupulously apply the work window restrictions from Caltrain's RFP, per SP01040.  Phase 1 has an average track availability of 13.3 track miles, while Phase 2 comes out to 12.1 track miles.  The weighted average of the two phases yields an average track availability of 12.7 track miles.  Bearing in mind that Caltrain has over 100 track miles to be electrified, this works out to a paltry ~12% of the railroad being available, a reflection of the extremely restrictive work windows.  This does not bode well for the program schedule, since having so little of the railroad available to the contractor will draw out the duration of all activities requiring access to the tracks.

    The burn rate works out to 3934 labor units per week, much of which is spent on mobilization and demobilization, as well as on weekend overtime work.

    The installation efficiency is 309 labor units per week per track mile.  When you consider that there are only 168 hours in a week, that is a terrible score indeed.
  2. Weekend Shutdown Scenario: One way to improve the average track availability is to completely shut down the railroad on weekends.  While this concentrates the majority of labor onto weekends when overtime rates are high, it opens up a 54-hour long period of uninterrupted access to segments 1 through 4a, while segment 4b and the yards remain partially open (to support tenant railroads and Caltrain maintenance activities).  This allows weekend work to be performed simultaneously in all segments, during both Phase 1 and Phase 2.

    Not surprisingly, average track availability improves considerably, with 35.3 track miles for Phase 1, 35.6 track miles for Phase 2, and a weighted average of 35.4 track miles.  By shutting down the railroad on weekends, we effectively tripled the amount of track access afforded to the contractor.

    The burn rate goes up quite a bit, because the entire railroad is being worked on every weekend.  The total works out to 8044 labor units per week.

    The installation efficiency is 227 labor units per week per track mile, a savings of 27%.
  3. Friday + Weekend Shutdown Scenario: The next possible step is to shut down the railroad on Fridays to extend the weekend work window to three days.  This has the advantage of increasing availability during a non-overtime weekday, but it is disruptive to riders who need to commute five days a week.  Weekend access increases from 54 hours to 78 hours, again with all four segments being worked simultaneously.

    Average track availability increases to 45.4 track miles.  Burn rate increases to 9144 labor units per week.  Installation efficiency improves to 201 labor units per week per track mile, a savings of 35%.
  4. Total Shutdown Scenario: The most draconian possibility is to shut down the railroad entirely.  It would be extremely disruptive for riders.  It could very well gridlock the highway 101 corridor, and in so doing, drive home the value of Caltrain for hundreds of thousands of commuters who never use Caltrain.  It would leave freight customers high and dry.  On the plus side, it would enable a coordinated construction "blitz" to complete the work at lower cost and far faster.  Electrification could even be combined with other projects such as grade separations.  Segment 4b and the yards would remain partially open (single-tracked) for the tenant railroads that use the southern end of the corridor.

    Average track availability would shoot up to 98.2 track miles.  Burn rate increases to 15600 labor units per week.  Installation efficiency improves to just 159 labor units per week per track mile, a savings of 49% (half off!)
Here are some graphs to summarize the results of this analysis.

You might wonder about the point of this exercise.  The RFP is closed and all the bids are in, so isn't all this overcome by events?

Word has it that the bids came in much higher than Caltrain expected, with contractors blaming the restrictive work windows for the higher cost.  Caltrain is now scrambling to scrape together even more funding than the $958M they thought electrification would cost (not including new vehicles).  Recall about half of that sum was estimated for re-signaling and building the overhead contact system, tasks where cost and schedule are strongly driven by work windows.

Shut Down This Railroad!

The right answer isn't to go digging between couch cushions for another several hundred million dollars.  The right answer is to shut down this railroad, because trying to electrify without shutting it down is like trying to change a flat tire without stopping your car.  A weekend shutdown would speed the work by a factor of nearly three, and reduce cost by about $150 million.  Shut down three days, save $200 million.  Shut everything down, save nearly $300 million.  Okay, maybe don't shut everything down, but at the very least, the weekends must go.