Side Streets, Downtown Streets, Highways, Parkways and Freeways

Posted by PITHOCRATES - July 31st, 2013

Technology 101

In 20th Century our Subdivision Planners shifted from Automobile-Friendly to People-Friendly Designs

The automobile changed how we live.  Where once we crowded into crowded cites and worked close to where we lived today we don’t.  Instead choosing to live in sleepy suburbs.  Away from the noise and congestion of city life.  Where we can relax after work.  And on the weekend.  Enjoying a beer in the shade in our backyard.  Our little Shangri-La.  Come Monday morning, though, it’s back to the grind.  So we back our car out of the garage.  And drive out of our little residential community.

If you live in an older suburb that would be a drive down a straight road.  Running either north and south.  Or east and west.  Bringing you efficiently to a larger road.  That you can efficiently take to a larger road yet.  With a higher speed limit.  With many of us eventually taking that road to an onramp of an interstate freeway.  For that morning commute.  Quick.  And efficiently.  Thanks to our city and suburb planners making our cities and suburbs so automobile-friendly.

Soon everyone was driving so much that these roads got congested.  Including the ones in our sleepy little subdivisions.  With people racing down our side streets to get to those bigger roads.  Filling our little Shangri-La with the sounds of traffic.  And making it unsafe for our kids to ride their bicycles in the street.  Which is why somewhere around the middle of the 20th century our subdivision planners shifted from automobile-friendly to people-friendly.  Instead of grids of straight lines crossing other straight lines at neat right angles our roads in our subdivisions began to curve.  If you ever tried to cut through a subdivision and got so turned around that you ended up where you entered this is why.  To discourage people from driving through our sleepy little streets.  So we can relax with that beer in the shade.  And our kids can ride their bicycles safely in the streets in front of our homes.

Design Speed is the First Consideration when Designing a New Road

Cars are big and heavy.  Trucks are even bigger and heavier.  Yet millions of them safely share the same roads every day.  And few in a small car look twice at a semi truck and trailer stopped next to them at a traffic light.  Or give a second thought to an even bigger and heavier freight train crossing the road ahead of them while they sit at a railroad crossing.  All because of lines painted on the road.  Speed limit signs keeping us driving at the same speed.  And stop signs and traffic lights.  Which people observe.  And give the right-of-way to others.  While they wait their turn to proceed.  Except for trains.  They always have the right-of-way.  Because trains can’t stop as easily as a car or a truck.  And they pay a lot of money for that right-of-way.

As we left our neighborhoods and got onto the bigger roads and drove to the interstate freeway the speed limit got higher and higher.  And the faster large things go the more kinetic energy they build up.  Making it harder to stop.  And to control.  That’s why trains don’t stop for cars.  Cars stop for trains.  Emergency vehicles, like fire trucks and ambulances, get the right-of-way, too.  When we see their lights flashing and/or hear their sirens we pull to the curb and stop.  Because they’re speeding to an emergency and need a clear road.  But also because they are often traveling faster than the design speed of the road.

Yes, design speed.  Not the speed limit.  Two completely different things.  It’s the first consideration when designing a new road.  How fast will traffic travel?  Because everything follows from that.  Curves, grades, visibility, etc., these are all things that vary with speed.  Engineers will design a downtown street with a lot of vehicular and pedestrian traffic for lower speeds than they’ll design a country highway that connects two towns.  Also, lane width in a downtown street can be as narrow as 9 feet.  And they can have sidewalks adjacent to the curbs.  Allowing narrower streets for pedestrians to cross.  Freeways, on the other hand, have lanes that are 12 feet wide.  And have wide shoulders.  Because faster vehicles need more separation.  As they tend to waver across their lanes.  So this is another reason why we pull aside for emergency vehicles.  As they may approach or exceed the design speed of a road.  So we give them wider lanes by pulling over.  As well as giving them a less obstructive view of the road ahead.

The Modern Interstate Freeway System is Basically an Improved Parkway

Old 2-lane country highways had narrow lanes and narrow shoulders.  Making it easy to drift across the center line if distracted.  Or tired.  Into oncoming traffic.  If a person hugs the shoulder because he or she is nervous about fast-moving oncoming traffic they could drift over to the right.  Out of their lane.  And drop off of the shoulder.  Which could result in a loss of control.  Even a rollover accident.  And if you were stuck behind a slow-moving truck on a grade there was only one way around it.  Moving over into the lane of oncoming traffic.  And speeding up to get ahead of the truck before a car crashes head-on into you.  In fact, there used to be a passing lane.  A 3-lane highway with one lane traveling one direction.  One lane traveling in the other direction.  And a lane in the middle for passing.  Which worked well when only one person passed at a time.  But did not work so well when cars from each lane moved into the passing lane at the same time.  Running head-on into each other.  That’s why you won’t see a passing lane these days.  They are just too dangerous.

In the 20th century we started making roads for higher speeds.  Parkways.  The traffic travelling in either direction was separated by a median.  So you couldn’t drift into oncoming traffic.  There were no intersections.  Crossroads went over or under these parkways.  So traffic on the parkways didn’t have to stop.  They also had limited access.  On ramps and off ramps brought cars on and off, merging them into/out of moving traffic.  And unlike the old 2-lane country roads there were 2 lanes of traffic in each direction.  So if you wanted to pass someone you didn’t have to drive into oncoming traffic to go around a slower-moving vehicle.  And there was a paved shoulder.  So if a car had a flat tire they could limp onto the shoulder to change their tire.  Without interrupting the traffic on the parkway.  Of course, being on the shoulder of a parkway was not the safest place to be.  Especially if some distracted driver drifted onto the shoulder.  And crashed into your broken down car.

The modern interstate freeway system is basically an improved parkway.  They have wider lanes and wider shoulders.  Along the median and the outside right lane.  Instead of the typical Windsor Arch of the parkway they have bridges of concrete and steel.  Allowing greater spans over the roadway.  Keeping those shoulders wide even under the overpasses.  Grades are less steep.  And curves are less sharp.  Allowing little steering inputs at high speeds to control your vehicle.  Making for safer travel at even higher speeds.  And a much greater field of vision.  Even at night where there are no streetlights.  The road won’t change grade or curve so great beyond the length of your headlights.  Safely allowing a high speed even when you can’t see what’s up ahead.  Little things that you’ve probably never noticed.  But if you exit the interstate onto a curvy 2-lane highway with steep grades you will notice that you can’t drive at the same speed.  Especially at night.  In fact, you may drive well below the posted speed limit.  Because you can’t see the summit of the next hill.  Or the curve that takes you away from a sharp drop-off to a ravine below.  Like you find around ski resorts in the mountains.  The kind of highways you can’t wait to get off of and onto the safer interstate freeway system.  Especially in a driving snow storm.

www.PITHOCRATES.com

Share

Tags: , , , , , , , , , , , , , , , , , , , , , , , , , ,

Steam Locomotive, Diesel Electric Locomotive, Interstate Highway System, Airplane, Air Travel, Refined Petroleum Products and Pipelines

Posted by PITHOCRATES - March 21st, 2012

Technology 101

The Diesel Electric Locomotive could pull a Train Cross Country and into the Heart of a City with Minimal Pollution

The 1920s were transformative years.  The Roaring Twenties.  It’s when we moved from animal power to mechanical power.  From the horse and plow to the tractor.  From steam power to electric power.  From the telegraph to the telephone.  From the gas lamp to the electric light.  From crowded mass transit to the freedom of the automobile.  From manual labor to the assembly line. 

You can see a glimpse of that world in 1920’s Steam Train Journey Across the United States – Westward Ho!  The beginning of the modern city.  With modern street lighting.  Electric power and telephone overhead wiring.  Streets crowded with automobiles.  Tractors and mechanical harvesters on the farm.  And, of course, the steam locomotive.  Connecting distant cities.  Transferring the freight to feed the modern industrial economy.  And shipping the finished goods.  As well as all that food from the farm to our grocer’s shelves.  Proving the 1920s were vibrant economic times.  With real economic growth.  And not a speculative bubble.  For there was nothing speculative about all of this technology becoming a part of our way of life.

Of course the technology wasn’t perfect.  The coal-burning locomotives belched black smoke and ash wherever they went.  Which wasn’t all that bad in the open country where a train or two passed.  But it was pretty dangerous in tunnels.  Which had to be short lest they suffocated their passengers.  (One of the reasons why all subways use electric trains).  Making for some long and winding railroads in mountainous terrain.  To go around mountains instead of under them.  Slowing trains and increasing travel time.  And they were pretty unpleasant in the cities.  Where the several rail lines converged.  Bringing a lot of coal-burning locomotives together.  Creating a smoky haze in these cities.  And leaving a layer of ash everywhere.  The cleaner diesel-burning locomotives changed that.  The diesel electric locomotive could pull a train cross country and into the heart of a city with a minimal amount of pollution.  As long as they kept their engines from burning rich.  Which they would if they operated them with dirty air filters.  Reducing fuel efficiency by having the air-fuel mixture contain too much fuel.  And causing these engines to belch black smoke.  Similar to diesel trucks running with dirty air filters.

Airplanes can travel between Two Points in a Direct Line at Faster Speeds than a Train or Bus with Minimal Infrastructure

Trains shrunk our country.  Brought distant cities together.  Allowing people to visit anywhere in the continental United States.  And the railroads profited well from all of this travel.  Until two later developments.  One was the interstate highway system.  That transferred a lot of freight from the trains to trucks.  As well as people from trains to buses and cars.  And then air travel.  That transferred even more people from trains to airplanes.  This competition really weakening railroads’ profits.  And pretty much put an end to passenger rail.  For people used the interstate highway system for short trips.  And flew on the long ones.  Which was quicker.  And less expensive.  Primarily because airplanes flew over terrain that was costly to avoid.

Highways and railroads have to negotiate terrain.  They have to wind around obstacles.  Go up and down mountainous regions.  Cross rivers and valleys on bridges.  Travel under hilly terrain through tunnels.  And everywhere they go they have to travel on something built by man.  All the way from point A to point B.  Now trucks, buses and cars have an advantage here.  We subsidize highway travel with fuel taxes.  Trucking companies, bus lines and car owners didn’t have to build the road and infrastructure connecting point A to point B.  Like the railroads do.  The railroads had to supply that very extensive and very expensive infrastructure themselves.  Paid for by their freight rates and their passenger ticket sales.  And when there were less expensive alternatives it was difficult to sell your rates and fares at prices high enough to support that infrastructure.  Especially when that lower-priced alternative got you where you were going faster.  Like the airplane did.

Man had always wanted to fly.  Like a bird.  But no amount of flapping of man-made wings got anyone off the ground.  We’re too heavy and lacked the necessary breast muscles to flap anything fast enough.  Not to mention that if we could we didn’t have any means to stabilize ourselves in flight.  We don’t have a streamline body or tail feathers.  But then we learned we could create lift.  Not by flapping but my pushing a curved wing through the air.  As the air passes over this curved surface it creates lift.  Generate enough speed and you could lift quite a load with those wings.  Including people.  Cargo.  Engines.  And fuel.  Add in some control elements and we could stabilize this in flight.  A tail fin to prevent yawing (twisting left and right) from the direction of flight.  Like a weathercock turns to point in the direction of the wind.  And an elevator (small ‘wing’ at the tail of the plane) to control pitch (nose up and nose down).  Ailerons correct for rolling.  Or turn the plane by rolling.  By tipping the wings up or down to bank the airplane (to turn left the left aileron goes up and the right aileron goes down).  And using the elevator on the take-off roll to pitch the nose up to allow the plane to gain altitude.  And in flight it allows the plane to ascend or descend to different altitudes.  Put all of this together and it allows an airplane to travel between points A and B while avoiding all terrain.  In a direct line between these two points.  At a much faster speed than a train, bus or car can travel.  And the only infrastructure required for this are the airports at points A and B.  And the few en route air traffic controllers between points A and B. Which consisted of radar installations and dark rooms with people staring at monitors.  Communicating to the aircraft.  Helping them to negotiate the air highways without colliding into other aircraft.  And air travel took off, of course, in the 1920s.  The Roaring Twenties.  Those glorious transformative years.

Refined Petroleum Products have Large Concentrations of Energy and are the Only Fuel that allows Air Travel

The most expensive cost of flying is the fuel cost.  The costlier it is the costlier it is to fly.  Not so for the railroads.  Because their fuel costs aren’t the most expensive cost they have.  Maintaining their infrastructure is.  They can carry incredible loads cross country for a small price per unit weight.  Without swings in fuel prices eating into their profits.  Making them ideal to transfer very large and/or heavy loads over great distances.  Despite dealing with all the headaches of terrain.  For neither a plane nor a truck can carry the same volume a train can.  And heavier loads on a plane take far greater amounts of fuel.  This additional fuel itself adding a great amount of weight to the aircraft.  Thus limiting its flight distance.  Requiring refueling stops along the way.  Making it a very expensive way to transport heavy loads.  Which is why we ship coal on trains.  Not on planes.

Trains are profitable again.  But they’re not making their money moving people around.  Their money is in heavy freight.  Iron ore.  Coke.  And, of course, coal.  To feed the modern industrial economy.  Stuff too heavy for our paved roads.  And needed in such bulk that it would take caravans of trucks to carry what one train can carry.  But even trains can’t transport something in enough bulk to make it cost efficient.  Refined petroleum.  Gasoline.  Diesel.  And jet fuel.  For these we use pipelines.  From pipelines we load gas and diesel onto trucks and deliver it to your local gas station.  We run pipelines directly to the fuel racks in rail yards.   And run pipelines to our airports.  Where we pump jet fuel into onsite storage tanks in large fuel farms.  Which we then pump out in another set of pipelines to fueling hydrants located right at aircraft gates.

These refined petroleum products carry large concentrations of energy.  Are easy to transport in pipelines.  Are portable.  And are very convenient.  Planes and trains (as well as ships, busses and cars) can carry them.  Allowing them to travel great distances.  Something currently no renewable energy can do.  And doing without them would put an end to air travel.  Greatly increase the cost of rail transport (by electrifying ALL our tracks).  Or simply abandoning track we don’t electrify.  Making those far distant cities ever more distant.  And our traveling options far more limited than they were in the 1920s.  Turning the hands of time back about a hundred years.  Only we’ll have less.  And life will be less enjoyable.

www.PITHOCRATES.com

Share

Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,