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Tue Mar 27, 2012, 02:45 AM


Here is a report on the USA's only "Personal Rapid Transit" System


The article mention the old 1960s to early 1970s Pittsburgh debate to replace its last Streetcars with an automated rubber tire transit system called "Skybus". The Skybus proposal pre-dated the above system in Morgantown, but ended up being cancelled in favor of an LRV System. The Skybus system was later used in many Airports as a people mover (But under different names).

The reason the LRV was adopted in place of Skybus was simple, the LRV system could move more people cheaper. The Morgantown "Personal Rapid Transit" PRT, is restricted in its length, 4 miles, and restricted to one lane. The LRV system could travel on the roads, on its own right of way and could go on BOTH of the lines it was to replace. Thus Morgantown's system works for them, but hard to get a similar system to work elsewhere.

More on the Skybus debacle of the 1960s and 1970s


In 1964 the present Pittsburgh Public Transit provider. Port Authority of Allegheny County (Often called PAT), had taken over the old Streetcar system of the Pittsburgh Railway system and replaced the streetcars with buses.

A problem arouse as to how to replace the last three Streetcar routes. These three routes were the remains of the two interurban branch of the Pittsburgh Railway system and as such went on they own right of way through most of the South Hills. To replace the last three Streetcar routes with buses meant running buses on the Highways the Streetcars avoided since the Streetcars had they own right of way. Compared to the Streetcars the buses would take two to three times as long given the highways they would be on were already known for their traffic jams.

In fact a test was done between the Streetcar and a car from the end of the Streetcar line to Downtown Pittsburgh by a local newspaper (Before the Old Streetcar line was closed down and rebuilt as an LRV). A passenger entered the streetcar (a regular streetcar NOT one reserved for this test) and the other reporter drove from that same point to downtown Pittsburgh. The Streetcar made all of its normal stops. The Automobile driver did beat the Streetcar rider to downtown Pittsburgh by about a minute. The Automobile driver did NOT even had time to park the automobile. The Auto driver downtown but was declared the "Winner" and everyone laughed for they knew parking the car would take at least another 10-15 minutes and thus it was clear the Streetcar was faster then taking a Automobile on that line.

I mention this for by the early 1960s it was quickly determined that a bus could NOT replace the Streetcars on these three lines, but PAT was committed to getting rid of Streetcars at all costs. Westinghouse Electric then proposed Skybus. Skybus was an elevated automated transit (no driver) rubber tire transit system.

As proposed, Skybus, could come as often as the old Streetcars (which on these last three routes came every 1-2 minutes during rush hour) but was restricted by the number of stops it could make. Given the Computer capacity at that time, it was decided that it would be impossible to use Skybus to replace every streetcar stop, instead it was decided to "Merge" two of the old Streetcar lines and convert the third line (and part of the Second line) to regular bus service that would feed into Skybus.

42/38 Beechview route

Before I go on, let me describe the last Three (four if you included a side line I will mention) Streetcar lines in Pittsburgh. The first was the 42/38 Streetcar line. This line had been build in 1905. A Tunnel had been build under Mount Washington so that the Streetcars could avoid Mount Washington. The Streetcars then went on its own right of way over Saw Mill Run (Where PA 51 would be built in the 1930s) and along the hillside above present day US 19. This right of way ended once it entered Beechview proper (Prior to the late 1940s, the Right of Way continued between two lane of traffic right through Beechview, in the late 1940s the Streetcar right of way was paved over and the roads on both sides expanded so the Streetcar ran on a road wide enough for Automobiles to pass it). As the Streetcar entered Dormont (the next community on the line) it cross a bridge over Wenzell Avenue and then on its own right of way.

The road, Broadway Avenue, to this day, runs on either side of the Streetcar right of way in Dormont. The Streetcar then crosses Potomac, at grade and Broadway Avenue ends. The Streetcar right of way continued to Mt Lebanon Township. At the border of Dormont and Mt Lebanon, the Streetcar Right of way ended and the Streetcar entered present day US 19 and continued on US 19 for about two miles (This two miles was replaced by a tunnel when the LRV was built in the early 1980s).

At the end of the trip on US 19, 42/38 entered the Clearfield Loop (Now a parking lot) and turned around to go back downtown. A connecting route did exist between the Clearfield loop and the Castle Shannon loop. About one Streetcar a day made the trip between the two loops, it was retained as a backup system if one of the two lines were out of order.

35 Castle Shannon

The Castle Shannon route went through the same Streetcar tunnel as the 42/38 Beechview route, then turned left onto an old, 1869 narrow gauge railway line that had been converted in 1905 to a Streetcar line. The line went on the hillside above Saw Mill Run, where PA 51 would be built in the 1930s. Three of the original narrow gauge railroad bridges survived on this route till it was closed down in the 1980s. A fourth bridge was built in the 1930s to take the Streetcar over PA 51. A tunnel had been built in 1905 to the Brookline Community of Pittsburgh, but not used after about 1910 (The Tunnel was built as part of the effort to increase the cost of the Wabash Railroad, then trying to enter Pittsburgh and break the monopoly the Pennsylvania Railroad had over all rail traffic in and out of Pittsburgh in 1900, but that is another story).

The 35 Castle Shannon line then went along PA 51 and then PA 88 to Castle Shannon. This is the same line the old 1869 narrow gauge railroad had used.

37 Library

At the same time the above two streetcar lines were being built, community leaders in Donora and other parts of the Monongahela Valley wanted competition as to how to go to Pittsburgh. Since Automobiles were still "primitive" at best AND the roads were terrible (Roads would NOT be improved till the Tax on Gasoline was imposed, but that only started in 1919 in the US) and the Pennsylvania Railroad (and its subsidy the B&O Railroad) controlled all the routes along the rivers, the people of that part of the Monongahela valley decided to build their own interurban streetcar line to Pittsburgh. They took the route to Monongahela PA, and then on its own right of way, along what would become PA 88 to Finleyville Pa. Outside Finleyville a bridge was built to take the Streetcars over the B&O rail line at Finleyville to Finleyville proper. Once in Finleyville, the Streetcars went on that towns roads, then on its own right of way. About a half mile out of town PA 88 turned to the left, but the Streetcar continued Straight ahead and after another half mile turn left (Via a Tunnel that lasted till the 1960s) to the town of Library Pa. On its own right of way through Library, crossing PA 88 on the other side of Library then along 88 through Bethel Park (in 1905 a rural farming area, but by the 1960s a heavy built up suburban area) till it reached Castle Shannon where it, at first, joined up with the 42/38 line into Pittsburgh. Within a few years the route was changed to the 35 Castle Shannon line (and the 35 Castle Shannon number was only used for Rush Hour Cars to supplement the cars from Library and Washington). In the early 1950s this route was terminated as to anything south of Library Pa, for Library was the last stop in Allegheny County. The line survived till the 1960s (and some parts can be seen today) but the Tunnels and bridges were torn down or filled in starting in the 1950s.

36 Drake

After the Donora line was built, it was decided to build an interurban to Washington PA, the County Seat of Washington County, the County south of Allegheny County, whose county seat is Pittsburgh PA. About a mile south of Castle Shannon (at a point now called Washington Junction) a new route turn right in the direction of Washington Pa and away from the Monongahela river. This route headed to intersect Washington Road, but did NOT intersect Washington Road till the border of Washington County. On the way it passed the area where in 1964 the First indoor mall was built in the Pittsburgh Area (South Hills Village). It took a Bridge over McLaughlin Run (over McMurry Road) at Drake road, then ran cross country till it crossed Washington Road as Washington Road entering Washington County. It then went on its own right of way (Which was taken over by the State of Pennsylvania in the early 1950s for the present alignment of Washington Road) through Thompsonville to Cannonsburg Lake. Just north of Cannonsburg lake the Washington Streetcar line went left of the present Washington Road Alignment then across the present Washington Alignment and on its own right of way to Chartiers Creek as Chartiers Creek passes Cannonsburg PA. The line went along Chartiers Creek till it neared Cannonsburg then took a one lane bridge across the B&O Tracks and Chartiers Creek into Cannonsburg proper (at, right is today the parking lot of Sarris Candy in Cannonsburg). The Streetcar line then went on Cannonsburg Streets to Houston Pa, then on Houston PA Streets then off and on streets til you get to Arden (Location of the Arden Trolley Museum, in an abandoned Car Barn for this line). then on its own right of way till its entered Washington PA, then on Washington Streets till the line terminated.

In the early 1950s this line was abandoned south of McLaughlin Run (The Drake Loop) do to the taking of the Right of Way for the then new Alignment of US 19, Washington Road.


Notice, the three routes had at one time or another reached into Washington County. All were more on their own right of way then public roads. By the time PAT was formed in the early 1960s, the routes South of the Washington County line had long been abandoned, but the routes North of that line were bringing in over 10% of all workers working in Downtown Pittsburgh, exceeding all other ways into Downtown Pittsburgh EXCEPT for the routes from Oakland and along the old Pennsylvania main line (converted to a bus lane in the 1970s).

Ending all Streetcar service

As I mentioned earlier PAT's plan was to end all Streetcar service as soon as possible after it took them over in 1964. The plan was to replace all Streetcar lines with buses. The problem was the above three lines (and the Arlington Line that ran up and over Mt Washington between the two entrances to the Streetcar tunnel, it acted as a backup system to the tunnel and continues in that role. this is the so call "Fourth Line" I mentioned above). Buses could NOT replace these three lines WITHOUT a considerable extension in time of any trip on these lines.

The Skybus plan

The Skybus plan was to run Skybus from Downtown Pittsburgh to the abandoned Wabash Tunnel, have a stop in Downtown Pittsburgh and the next stop on the other end of the Wabash tunnel. Then take Skybus over Beechview to the next stop which was to be in Dormont on the Dormont-Pittsburgh Border (and reducing all service to Beechview to Buses between these two stops). From Dormont the plan was to take Skybus over Dormont and US 19 in Mt Lebanon (where another stop would be, with buses stopping they from the rest of the South Hills), then to Castle Shannon where a Stop would be built, then to Washington Junction, where the Library route would be converted to a bus lane and the buses would run back and froth from this stop to Library. then a final stop at a new station to be built opposite South Hills Village.

problem Number One, Beechview

This plan had two big problems, the two communities that had grown up around the two lines were also the most dependent on the Streetcars. The plan called for the Library line to be converted to a bus way and to have people go by bus to the Skybus stop, then Skybus to Downtown Pittsburgh. In Beechview the plan was the same, to have people take a bus to one of the two Skybus Stops then Skybus. As a result both communities "Revolted".

I lived in one of those communities, Beechview. The plan for Beechview was to have one stop off PA 51 and a second stop in Dormont. Beechview, which had been built in 1905 with the Streetcar line as its ONLY connection with Downtown Pittsburgh would be converted to a bus feeding line connecting the two Skybus Stops (You can travel by Automobile from Beechview to Downtown Pittsburgh but it takes twice as long).

The bus feed lines would follow the old Streetcar line between the Skybus Stops (Actually Worse, the Stop off PA 51 was NOT on the old Streetcar line. the old Streetcar line had gone through Beechview and swang north to Downtown Pittsburgh through its own tunnel, Skybus would use a abandoned railroad tunnel into Downtown Pittsburgh with its stop on that tunnel, thus Beechview which had Nine Streetcar Stops would be bypassed completely, those stops would become bus stops, that would take residents to the two Skybus Stops on either side of Beechview).

As you can see Beechview could NOT see how the plan would benefit Beechview, they would lose eight stops that went right to Downtown Pittsburgh, in exchange for Ten bus stops that would take them to another stop to catch the Automated System.

Problem Number Two, Bethel Park

Bethel Park was the other community affected. The plan called for the Streetcar right of way in Bethel Park to be replaced by a bus way, that would go to the Skybus stop at the end of the Bus way. Again ending any direct connection in exchange for a bus to take you to the Skybus line. Again DIRECT connection would be lost and the people of Bethel Park rejected the plan.

The Alternative the no one wanted to hear

One of the main opposition to Skybus was WHY replace a more then adequate Streetcar system when the two biggest transit stops in the County would be still connected only by buses? If you only wanted Seven stops, why NOT build it between Downtown Pittsburgh and Oakland? This was brought up often, and then ignored, for Skybus was NEVER intended to improve transit service, but to get rid of the last three Streetcar lines. This was clear when finally in the mid 1970s the Federal Government ORDERED PAT to do an actual STUDY on how to improve transit along the old Streetcar line and the Study came out solidly in favor of Streetcars (In the form of LRVs). Yes, average speed along the route would be about 13 mph, but that is still FASTER then the automotive traffic speed in the corridor.

Cost of all three systems were considered (Skybus, LRV and buses) and the LRVs came out the cheapest of all three. Buses were restricted as to how many people they could carry, thus having the highest cost per passenger mile. Skybus would have the lowest cost per passenger mile (no operator, thus lower costs) BUT once you take into consideration the bus drivers needed to transport people between the stops, its cost actually exceeded that of buses. Thus the LRVs came in as the lowest cost per passenger mile and thus the old Streetcar system was replaced by a more modern LRV system, but one basically following the routes first laid down in 1869 and 1905.

The same problem comes up in other versions of Personal Rapid Transit, the cost to GET to the PRT is much higher then the PRT, but you have to take BOTH into consideration when judging which can be the most cost effective system. In a highly populated area a PRT system running from a LRV station to nearby population centers can make the over all system more efficient but you MUST consider the overall system not just one part of it. When that is done Streetcars/LRVs tend to win out in high population areas. Buses tend to win out in low population areas. Mongantown's PRT works for it is going from one high population area, its old campus, to another high population areas, its new campus. My father always said Skybus would be ideal between Downtown Pittsburgh and Oakland but NOT between Pittsburgh and its suburbs.

The problem was PRTs are lousy selections in most situations, LRVs or buses tend to be better choices (And in real low population areas, i.e. rural area, automobiles are still supreme). LRVs can carry more people at lower costs to and from high population areas, while buses work better in moderate population areas.

Combination LRV and Skybus service

An "ideal" situation would be an LRV line between Downtown Pittsburgh and Oakland, one stop in each place, but with at least two Skybus type systems between the two express stops (one via Center Avenue the other via Fifth both going to Downtown Pittsburgh, best solution is one is the return route of the other, i.e. goes Centre to Oakland then Fifth to Pittsburgh, OR Fifth to Oakland then Centre to Pittsburgh).

You could also have an additional two from that location, the first one to Highland Park and the Pittsburgh Zoo and the Second to CMU and Squirrel Hill.

The LRV two locations would be Downtown Pittsburgh then along the old Pennsylvania Main line then take the Schenley Tunnel to Carnegie Library and Museum. The second stop would be at that location with all four PRT line going from that location (i,e. West via Fifth, North then west via Centre, North then East to Highland Park, and South and east to Squirrel Hill.

More on the Schenley Tunnel:

The LRV would be in a good center location, between CMU and Pitt, and all four PRT would feed into the LRV. The tunnel would have to be expanded to permit two lanes of traffic and double track so PAT's 5'2" LRVs could go on the railroad line which is standard gauge, 4'8". Nice express service via the LRV and constant service via the Skybus routes.

This would also permit the LRV line to go to Hazelwood and then along the Monongahela river to McKeesport or even West Muffilin (Or avoid the Schenley Tunnel and head for Monroeville nd the Montorville Mall area). The key is to use ALL three systems, Skybus/PRT, LRV and Buses where each is the best choice. Skybus/PRT can even wait (tell people to use bicycles or walk instead or even the bus) till the LRV system in finished. You need a back bone for any transit system and over the last 100 years Streetcars/LRVs have constantly been found to be the best backbones in urban areas.

Similar express LRV routes could be built elsewhere along the Railroad lines that criss cross Pittsburgh, feed by Skybus type PRTs. The key is in high population areas to move mass transit OFF THE ROADS, the best way is LRVs (for it can go off and on the road as needed to reduce cost or reduce congestion). LRVs do NOT need to be a complete interconnected system, it can rely on present day rail lines and highways (as needed), thus reducing cost to construct (unlike the PRT which MUST have its own right of way).

Comment on Bus Rapid Transit (BRT). While workable, given that buses are diesel, you have to address issue of ventilation in any underground system. Streetcars/LRV solve this problem by being electric, thus less need for fresh air. Once you decide to go on your own right of way as much as possible, rail makes more and more sense, it requires less energy to operate on and by its nature precludes people pushing for automobiles to be permitted on the right of way. I can see BRT in certain limited situations, but unlike streetcars/LRV that are restricted to their tracks, buses require some safety distances in case they get to close to each other, thus BRTs can NOT be as narrow as LRVs systems thus tend to have increase costs when you are looking at retrofits into an urban area.

More on Pittsburgh Skybus proposal of the 1960s:

Video of the Skybus system in operation on its experimental track in Allegheny County's South Park:

An old DU2 site on Skybus:

The 1967 "Study" on Skybus, that was later rejected by another, more detail study, in the mid 1970s:

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Reply Here is a report on the USA's only "Personal Rapid Transit" System (Original post)
happyslug Mar 2012 OP
nxylas Mar 2012 #1
happyslug Mar 2012 #2
nxylas Mar 2012 #3
happyslug Mar 2012 #4
nxylas Mar 2012 #5

Response to happyslug (Original post)

Tue Mar 27, 2012, 09:34 AM

1. How could LRVs be cheaper?

PRT systems miraculously defy all the laws of economics by going into profit the second they open, or so I've been told.

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Response to nxylas (Reply #1)

Tue Mar 27, 2012, 11:29 AM

2. No Transportation system has EVER broke even...


Even Adam Smith in his "Wealth of Nations" reported that already known fact at that time (1770s). Transportation has always been subsidized by other parts of the economic system for that reason.

Report from the City of Seattle that general revenues provide TWICE the revenue for road repairs and construction then gasoline tax:

Nationally, Gasoline taxes pay barely 50% of the cost of building and maintaining the road system in the US:

Report that Gasoline and other user fees pay only about 80% of the direct costs to maintain the current road system:

Here is a right wing site, but gives a good history of when Gasoline taxes where passed in every state, it gives the right wing position of NOT increasing gasoline taxes:

Just to show that even the Highway system is subsidized.

As to PRTs, they can be "profitable" if you ignore the cost to build the system. (i.e. only count the cost of operating the system). Given that such costs are the main cost involved, PRTs can, in theory, be cheap to operate once opened.

The primary reason for this is that roughly 80% of almost every public transportation system is the cost of drivers and maintenance. No drivers, lower cost of operation.

The problem is such no operator systems, even today, require exclusive right of way that is isolated from most foreign objects (i.e elevated or underground so to avoid any animals running on the Right of way and getting hit by the PRT). No exclusive right of way, no PRT. Thus construction is the single biggest cost, and the best way to keep such costs low is to build a very limited system. Thus Morgantown system was built and has NOT been copied. To limited except in a situation much like West Virginia University with its two campuses.

Furthermore even the PRT has maintenance problems, tires have to be replaced, power cables have to be replaced. The cars have to be cleaned every day. This all requires people, which cost money. Once you add these costs to most proposed PRT systems, any savings in term of operating costs, i.e. no drivers you have to pay, is offset by the fact the cost to collect fares, clean the cars and maintain the right of way would still exists. Furthermore, people want security, the driver provides that security, no driver some sort of security will have to be provided by having an on car security guard or police officers, thus off setting any savings do to NOT having a driver.

In the Skybus proposal, cameras were proposed on all cars and stations, till the federal government ask how would such camera PREVENT a crime? Cameras can record a crime, but unless you have someone watching the camera it 24/7, cameras can NOT even increase the speed of reporting such crimes (and again the people watching the Cameras would have to be paid, thus again killing any savings in NOT having a driver).

Yes, the problems of having a driver-less system slowly increase till the cost savings of such driver-less systems no longer made economic sense. Morgantown avoids this issue by being in a small town, larger cities that have looked into PRTs keep running into this problem. The small cars of the Morgantown system would NOT work in larger systems, the cars are to small for the volume of traffic (The Pittsburgh Skybus proposal involved much larger vehicles then the Morgantown System).

My point is PRTs tend to have very low operating costs, but much higher construction costs and continued maintenance costs. Together with the limited number of stops such a system can operate with, limits the usability of PRT systems. LRVs can handle larger number of people per worker (Driver AND maintenance personnel) over more stops AND have lower cost of construction given they have human operators and thus can operate with traffic OR on their own right of ways THAT are not cut off from interaction with nature (i.e. the operator can stop an LRV to let a deer cross its path, a PRT can not, this ability permits lower constriction cost of LRV's right of way over PRT's right of ways).

In my example I gave, I tried to set up a system that used the best of both the LRV (ability to use existing rail corridors and carry large volume of people) with PRT's ability to have a lot of cars moving all the time to other high population areas. This would require transfers, but is doable (Through it may be better to set up the proposed PRTs as Streetcars that connect with the LRV's line, i.e. on street streetcars on the proposed PRT lines, but when they hit the LRV line in Oakland they take the LRV line stright to downtown Pittsburgh as they own LRV, thus avoiding the need for transfers).

But back to my point, no transportation system has ever broke even, even the Airline industry depends on Federal subsidies in construction of Airport runways (and local subsidizes in construction of terminals). To demand any transportation system to break even is to ignore the long history of such systems NEVER making money.

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Response to happyslug (Reply #2)

Tue Mar 27, 2012, 07:33 PM

3. Oh, I know that

I was spoofing the pie-in-the-sky utopianism of the "pod people", who actually make this wild claim without explaining how such a thing is possible.

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Response to nxylas (Reply #3)

Wed Mar 28, 2012, 11:34 AM

4. But I have run across them also, they DO believe PRTs is the ideal "Solution"


And for that reason I had to point why such a position is untenable. I am sorry, but I have run across some people who would make the statement you made AND ACTUALLY BELIEVE IT, thus I had to respond as if it was what you actually believe to be true. I regret any problems cause by my assumption that what you were saying was what you actually believe to be true.

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Response to happyslug (Reply #4)

Wed Mar 28, 2012, 05:09 PM

5. No problem

I know this isn't a private conversation and that you have to write for an audience. I just didn't want anyone to think I believed that stuff.

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