BIKE: Bikes and monorails

[Nawdry]

At 09/10/2004 18:27 , Patrick Goetz wrote:

>Even with drivers, the operating costs of monorail are automatically half 
>that of light rail in an urban environment, as the average speed of 
>monorail is easily double that of light rail, meaning you only need half 
>as many vehicles (half as many drivers, half as much maintenance, half the 
>capital expenditures on vehicles, half as many maintenance techs, etc.) in 
>order to meet the same headways.  Let me explain for the mathematically 
>disinclined.  Suppose you have a circular, 15 mile track and you'd like to 
>have a train show up every 1/2 hour at a particular station.  If you have 
>a 15mph light rail system, you will need to run 2 trains in order to meet 
>this headway, as any 1 train will take an hour to get around the 
>track.  If you have a 35-40mph monorail you can meet a slight better than 
>1/2 hour headway with just 1 train.

As usual, Patrick's foray into monorail hawking with transit-flavored 
technobabble is just so much snake oil hype. The average speed depends on 
station spacing, not the technological mode.  Appended below is a posting I 
made to this list back on 20 July, addressing this very issue.  This 
compares the 17.5-mph Las Vegas monorail (back in the days when it actually 
ran) to several LRT lines - clearly, the monorail is hardly double their 
speed and in fact in some cases is slower than LRT, depending on the 
conditions.  The Green Line LRT in LA, for example, makes a whopping 38-mph 
average schedule speed (about equal to the BART regional-rail system in the 
Bay Area) - but that's with an average station spacing of about 1.5 
mile.  The much-vaunted monorails in Japan and Malaysia have about the same 
speed as the LV monorail, or slower in some cases.

If Patrick's entire "monorail profit" conjecture is predicated on 
monorails' having twice the average speed of LRT, his financial scenario 
will come crashing down faster than the parts are dropping off the 
Bombardier trainsets in Vegas.

LH

forum
07/20/2004 00:25
Re:  Monorail opens in Vegas

At 2004-07-18 13:38, Patrick Goetz wrote:

 >>The average speed of the LVM is misleading.  This relatively short system
includes 7 stops and 4 90-degree turns (see the route map at
http://www.lvmonorail.com/about_04_fastfacts.html), which is why the
average speed is so low.  Further, the Las Vegas Review Journal reports
that the route is actually 4.4 miles, in which case the average speed would
be 18.85 mph.

According to the American Public Transportation Association, the
Aaverage Street Rail Speed (FY2002) is 15.3 mph
(http://www.apta.com/research/stats/rail/lrsum.cfm), which includes lots of
long straight segments.  The bottom line is that the short, circuitous,
many-stopped Las Vegas monorail is still 15-20% faster than the any LRT
system in the country, on average.  That's pathetic.<<


This is by far not the most egregious of Patrick's deceptions, but it is
certainly one of the easiest to correct.  And, since I still have allowance for
another posting within my daily limit before midnight strikes, I'll set it 
right.

The route length of the Las Vegas monorail is indeed 3.9 miles, as
Michael Bluejay stated, and thus the average speed is indeed about 17.5
mph as Dave Dobbs reported.

That's based on the ACTUAL end-to-end running speed - not including
layover and "housekeeping" time at the end of each run.

To this SCHEDULE speed, Patrick compares the reported average total
daily OPERATING speed for light rail transit. There are two problems with
this.

First, it's an AVERAGE of ALL the "light rail"-classified operations in the
country - including relatively slow historic streetcars in places like New
Orleans, Memphis, and the Seattle Waterfront line.

More serious - it includes layover and turning time at the end of each run -
time spent by operators having a smoke, drinking coffee, and reversing
their vehicles or trains.

You don't have to be a rocket scientist to understand that Patrick is using
an apples-to-oranges comparison here - and is basically trying to flim-flam
you.

If he tried this in a graduate logic seminar, he'd flunk.

It makes far more sense to compare the LV monorail's end-to-end time to
the similar end-to-end  running time of a surface LRT line.  Portland's
Eastside line, for example, takes 47 minutes to traverse 15.0 miles - an
average of 19.1 mph (with lots of street and median running plus a
segment alongside the Banfield Expressway).  This line, too, includes
serpentine and right-angle turns, plus some fairly steep grades.  San
Jose's LRT, routed in a boulevard median between Civic Center and
BayPointe, averages 16.2 mph.

Sound planning decisions - monorail, light rail, "BRT", PRT, or whatever -
need to be made with sound, reliable information.  Playing carnival-sucker
games with numbers does a disservice to us all.