Snow Ski

Posted by PITHOCRATES - February 26th, 2014

Technology 101

Gravity and Speed keeps a Skier’s Skies in contact with the Mountain and Provides Control

The Winter Olympics have come and gone.  And if you are a big fan of the Winter Olympics you probably were somewhat disappointed.  Especially if you’re a fan of alpine skiing.  Because it was just too warm.  They have the Olympics in February for a reason.  Because February is a very cold month.  And the mountains have a couple of months of snow on them by February.  Allowing the snow groomers to do their magic.  And turn those mountains into hard sheets of ice.

Yes, ski racers ski on ice.  Not snow.  If you ever skied on a mountain where there was once an Olympic downhill racecourse you will see very steep slopes of ice.  If you ski slowly across the fall line of the slope at the top of the mountain you will slide further down hill than you ski across the slope.  With your ski edges sliding across the ice.  And about the only thing that will stop your ‘free-fall’ slide down that steep ice-covered slope is the loose snow on the sides of the slope.  But if you travel down this same slope at speeds around 70 mph your skies will carve into that ice.  Giving you great control.  If you have the skills of an Olympic downhill skier, that is.  If you’re not as skilled as a downhill racer then you shouldn’t try this.  Because if you fall at speed up there you can do some real damage to yourself.

Downhill skiers love that speed, though.  And will give themselves up completely to gravity.  And let it pull them down these steep, sheets of ice at breakneck speeds.  With nothing to keep them from flying off the mountain and breaking their necks but their skies.  As gravity and speed keeps their skies in contact with the mountain.  Giving them control to stay on their skies.  And carve their way down the mountain.  Literally.

When a Skier leans over on a Ski the Curved Edge of the Ski carves into the Snow or Ice and Turns the Skier

In alpine skiing there are 5 different races.  The downhill.  The super giant slalom (known as super G).  Giant slalom.  Slalom.  And combined.  Which is a combination of two ski races.  One downhill race and one slalom race.  The downhill is the straightest and fastest down the mountain.  The super G is a little more ‘turny’ and a little slower than downhill.   The giant slalom is more ‘turny’ and slower than Super G.  And the slalom is more ‘turny’ and slower than giant slalom.  The downhill is all about speed.  The turns aren’t that sharp.  While the slalom is all about the turns.  With speeds that aren’t that fast.

Each of these races requires different types of skies.  The downhill race needs long skies that will absorb the bumps of rough terrain without bouncing off.  And speed is more important than turning.  While slalom skies need shorter skies to make sharper turns.  And because they are shorter they may come off the snow as they bounce over rough terrain.  So they match the ski to the race.  And because of the requirements of downhill racing these skies are available only to professional skiers.  You will not find them in any sporting goods store.  As amateur and recreational skiers could not control them safely on steep sheets of ice at downhill speeds.

If you look at a ski lying on the ground you will see that it is narrower at the center where it attaches to the ski boot and wider at the tip and the tail.  And it goes from wide to narrow to wide in a continuous curve.  This curve is the side-cut radius.  This is what turns the ski.  When a skier leans over on the ski the curved edge of the ski carves into the snow or ice.  Turning the skier.  The more curved the side-cut radius the tighter turns it will allow.  So slalom skies are more curved in the side-cut radius than downhill skills.

The Winter Olympics are in February so Ski Racers can ski on Mountains that are Hard Sheets of Ice

Looking at a ski resting on a hard surface you will notice something else.  The center of the ski will be off that hard surface.  While the tip and the tail will be in contact with that surface.  This arch—or camber—of the ski helps to force the ski into contact with the snow when you place weight onto them.  Especially the steel edges when turning.  When a skier carves a turn he or she will literally carve that turn into the ice of the mountain.  In a clean turn the tail of the ski will follow the same groove carved by the tip.  With a minimum loss of speed.  If the tail slides out of this groove and carve its own groove it will slow the skier down.  And in downhill skiing where first and second place can be separated by one one-hundredth of a second one slight skid in a turn can be the difference between winning and coming in second.

As downhill skiers leave the starting gate they will take a couple of pushes with their ski poles to help gravity pull them down faster and then assume a tuck position.  To decrease their air drag.  As they approach a gate they will turn by leaning on their edges.  The sharper the turn the more they will lean onto to their edges to carve a tighter turn.  And the more speed they will lose.  Which is why racers will look for the best ‘line’ down the mountain.  One that minimizes sharp turns.  Once out of the turn they will release their edges and ski on the bottom of their skies.  Gaining speed.  They will absorb the rough terrain in their legs.  And fight the compression of the g-forces with their legs.  They lean into turns, release their edges, ride on the bottoms of their skis in the flats, lean on their edges, etc.  At speeds around 70 mph.  As they carve their way down a mountain of ice to cross the finish line in the shortest amount of time.

As spring approaches the ski resorts warm up.  Some people love this.  Spring skiing conditions.  Loose snow on the slopes but warming weather.  So warm that a lot of ski areas will have events like bikini races or lingerie races where girls will ski down the mountain half naked in the warming weather.  It can be a real party on the slopes.  But the skiing will be horrible.  The snow will be melting.  It will be wet.  Granular.  Pushed up into piles.  Making it easy to catch an edge and fall.  And difficult to build up any speed.  Which is why the Winter Olympics are in February.  In the coldest part of winter.  With a lot of snow frozen on the mountain.  And they typically don’t hold them in subtropical climates.  Where the average temperature in February is 50 degrees Fahrenheit.  Like in Sochi, Russia.  Where skiers had to deal with spring skiing conditions.  And varying conditions.  As the snow at the top of a run was different from the snow at the bottom of the run.  Despite the amount of chemicals they put on the snow to try and raise the melting temperature of the snow.  Making these Winter Games not as good as past Winter Games.  If you’re a fan of alpine skiing, that is.  Or prefer seeing cold winter vistas at the Winter Olympics.  And not people lying on the bare grass catching a suntan.

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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.

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