High-Speed Train crashes in Spain because things moving at High Speeds on the Ground can be Very Dangerous

Posted by PITHOCRATES - July 27th, 2013

Week in Review

Trains are heavy.  Getting a train moving is one thing.  But getting it to stop is another.  Because heavy things moving fast have a lot of kinetic energy.  The energy of something in motion.  In classical mechanics we calculate the kinetic energy by multiplying one half of the mass times the velocity squared.  That last part is really important.  The velocity part.  For as the speed increases the kinetic energy increases by a far greater amount.  For example, a train increasing speed from 30 kilometers per hour (18 mph) to 190 kilometers per hour (114 mph) increases its speed by 533%.  But because we square the velocity the kinetic energy increases by 3,911%.   Making high-speed rail more dangerous than regular rail.  Because of the great amounts of kinetic energy involved.

Airplanes are very heavy.  They travel at great speeds.  And have great amounts of kinetic energy.  Which is why plane crashes or so horrific.  Anything with that amount of kinetic energy suddenly stopping dissipates that energy in great heat, noise and the explosion of solid parts.  But plane crashes, thankfully, are rare.  For when they are travelling at those great speeds they’re up in the air thousands of feet (or more) away from anything they can hit.  And if there is a malfunction they can fall safely though the sky (with enough altitude) until the pilots can recover the aircraft.  For airplanes have the best friend to high speed objects.  A lot of empty space all around them.  Not so with high-speed rail (see Driver in custody after 80 killed in Spain train crash by Teresa Medrano and Tracy Rucinski posted 7/25/2013 on Reuters).

The driver of a Spanish train that derailed, killing at least 80 people, was under police guard in hospital on Thursday after the dramatic accident which an official source said was caused by excessive speed.

The eight-carriage train came off the tracks, hit a wall and caught fire just outside the pilgrimage destination Santiago de Compostela in northwestern Spain on Wednesday night. It was one of Europe’s worst rail disasters…

Video footage from a security camera showed the train, with 247 people on board, hurtling into a concrete wall at the side of the track as carriages jack-knifed and the engine overturned…

El Pais newspaper said the driver told the railway station by radio after being trapped in his cabin that the train entered the bend at 190 kilometers per hour (120 mph). An official source said the speed limit on that stretch of twin track, laid in 2011, was 80 kph…

Investigators were trying to find out why the train was going so fast and why security devices to keep speed within permitted limits had not slowed the train…

Spain’s rail safety record is better than the European average, ranking 18th out of 27 countries in terms of railway deaths per kilometers traveled, the European Railway Agency said. There were 218 train accidents in Spain between 2008-2011, well below the EU average of 426 for the same period.

There are no rails to derail from in the air.  And no concrete walls to crash into.  Air travel requires no infrastructure between terminal points.  High-speed rail travel requires a very expensive, a very precise and a highly maintained infrastructure between terminal points.  As well as precise controls to keep the train from exceeding safe speeds.  Planes do, too.  But when you have thousands of feet of nothingness all around you there is time to make adjustments before something catastrophic happens.  Like derailing when speeding through a curve too fast.

Air travel is safer than high-speed rail travel.  Which is why when a plane crashes it’s big news.  Because it happens so rarely these days.  Thanks to good aircraft designs.  Good pilots.  And having thousands of feet of nothingness all around you when flying at speeds close to 950 kph (570 mph).  Unlike having a concrete wall just a few feet away from a train traveling at high speeds.

High-speed rail may work in France and Japan.  The only two rail lines to pay for themselves are in these countries.  But every other passenger rail line in the world needs a government subsidy.  Because the costs of a rail infrastructure are just so great.  Making high-speed rail more of a source of union jobs than an efficient means of transportation.  Which is why they are a fixture in countries with liberal governments.  Who subsidize the high cost of these union jobs with taxpayer money.  In exchange for votes in the next election.

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LESSONS LEARNED #56: “It’s competition in the private sector that makes life better. Not government regulation.” -Old Pithy

Posted by PITHOCRATES - March 10th, 2011

Deregulation makes Air Travel Cheaper and Safer

A lot of people bitched about the deregulation of the airlines.  Mostly union people.  Because before they were deregulated it was very expensive to fly.  Ticket prices were out of the reach of most of middle class America.  But, with those high prices, the airlines made a lot of money.  And the unions got a lot of that money.  Union members warned about safety with deregulation.  If they lowered ticket prices so anyone could fly there wouldn’t be enough money to maintain the highly skilled personnel to fly and maintain the airplanes.  If you put profits before safety planes could start falling out of the sky.

Well, they deregulated the airlines in 1974.  Government no longer controlled the price of tickets, air traffic routes or the number of airlines allowed to operate.  Ticket prices fell.  More airlines began operations.  More cities built airports.  More people were flying than ever before.  All people.  Not just the rich.  Deregulation was a huge success.  Except for unions.  For them it wasn’t quite the gravy train it was before deregulation.  So did safety suffer?  No.  Quite the contrary.

In 1959 there were 40 fatal accidents per million departures (at the beginning of the jet age).  That number fell to about 10 in 1960.  During the Sixties it was at or below 5.  The number fell by approximately half during the Seventies.  It fell to about 1 after the Seventies with a spike of about 1.5 in 1988.

At the beginning of the jet age, few in the government bureaucracy knew anything about jets.  So it was mostly the manufacturers and the airlines policing themselves as they developed jetliner travel.  And they did a pretty good job.  After deregulation air travel exploded with the new jets.  They were safe enough that people weren’t afraid to fly on them.  And they did.

Boeing and Douglas lead the way in the Jet Age

Competition drove early jet travel.  Air travel was growing and the airlines needed planes that could carry more people, fly farther and faster.  If they had the planes they could fly the people.  Two of America’s manufacturers stood up in a big way.  Boeing built the 707.  And Douglas built the DC-8.  This competition produced two jetliners that were safe to fly and they moved more people farther than any propeller plane.  There were some accidents in the beginning but they were less compared to the propeller planes they replaced. 

Air travel continued to grow.  There was a demand for bigger airplanes.  A bigger plane could move more people at a lower cost per person.  This meant even lower ticket prices.  And made air travel more affordable to the less rich.  Boeing rolled out the 747.  McDonnell Douglas (the merger of Douglas with McDonnell Aircraft Corporation) rolled out the DC-10.  The first of the wide-bodies.  The Boeing 747 went on to become a huge success with an incredible safety record.  It still flies today.  Few airplanes make people feel safer.  The DC-10, on the other hand, did not make people feel as safe.  For a period of time.  And that marked the beginning of the end of McDonnell Douglas.

McDonnell Douglas was a very successful company.  They built thousands of DC-9s and MD-80/90s.  Over 2,000.  These are very reliable and safe aircrafts.  The DC-9 had only 0.76 fatal accidents per million departures (PMD).  The MD-80/90s had only 0.31 fatal accidents PMD.  You’ll still see a lot of these flying today.  It has proven to be a very reliable airframe.  The DC-10, though, had a bumpier road with less than 500 built.  It, too, was a good airplane.  But it was involved with some very high-profile accidents.  And it got a reputation as an unsafe design.

A Close Call with the Cargo Hold Door of a DC-10

The cargo hold door on the DC-10 opened outward.  This allowed room for more cargo.  Doors that open in take up cargo space.  Which reduces revenue.  The more cargo you can carry, the more revenue you make and the lower ticket prices can be.  It’s just one in many ways to reduce the cost of air travel.  And it was yet another thing that made the DC-10 profitable to fly.

Airlines bought the DC-10 and put it into service.  It performed well.  But that cargo door would become an issue.  Doors on an airplane typically open inward.  For a good reason.  Once a plane reaches an altitude of 10,000 feet, it has to be pressurized so people can breathe normally.  That places a lot of pressure inside the passenger and cargo compartments.  The only ‘holes’ in the aircraft have doors that seal tighter at these higher interior pressures.  Because they open inward.  The cargo door on the DC-10, though, needed a special latching mechanism to withstand those pressures without opening in flight.  Because it opened outward.

Closed properly there was no problem.  But sometimes it wasn’t.  In 1972, a DC-10 departing from Detroit suffered an explosive decompression as it climbed above 10,000 feet.  The cargo door failed.  The sudden decompression collapsed the passenger floor and damaged the aircraft’s control cables and hydraulics.  The rudder was deflected full left.  The engines throttle levels slammed back to idle.  The tail-mounted engine control cables were severed completely.  The elevator provided little control.  The pilots varied the thrust on the wing-mounted engines to maneuver the aircraft back to the airport.  They compensated for the deflected rudder with asymmetric thrust on the wing engines.  Without a functioning elevator the nose dropped at lower speeds.  So they landed at a higher speed than normal.  As they slowed the force of the rudder declined and the asymmetric thrust took over, pulling the aircraft off the runway.  It was a tremendous piece of flying by the crew that brought that plane back without loss of life.

A Pair of Crashes Threaten the DC-10 and McDonnell Douglas

The rear cargo door was studied and some changes were made.  Issues with floor strength in the new wide-bodies were questioned.  They just started flying.  This was new territory for everyone.   No significant change was made.  Other DC-10s were flying safely.  This may have just been an isolated incident of human error (closing the cargo door incorrectly).  Then, in 1974, it happened again.  In a series of human errors that doomed a Turkish Airlines plane leaving Paris for London.  A different seat configuration put more people over the floor that collapsed on the Detroit flight.  The explosive decompression tore through the cabin floor, causing greater damage to the control cables and hydraulics than on the Detroit flight.  There was nothing the flight crew could do.  The plane was uncontrollable.  It crashed, killing all 346 aboard.  The largest loss of life to date.  And the first crash of a new wide body.

The subsequent investigation painted the DC-10 as unsafe.  Then in 1979 another catastrophic accident at Chicago’s O’Hare airport.  During takeoff.  After passing V1 (the speed the aircraft could no longer abort and stop safely on the runway) the left wing-mounted engine and pylon tore away from the wing.  The pilots had no idea what had happened other that an engine had lost all thrust.  They couldn’t see the wing from the flight deck.  So they followed procedures for a two-engine takeoff.  But the damage to the leading edge of the left wing was severe.  The leading edge slats retracted with the severing of the hydraulic lines.  The left wing now had a slower stall speed than the right wing.  But they didn’t know.  And they had no indication in the cockpit.  The plane was flying.  They climbed out per procedure.  They powered back from take-off power.  And when they did, the left wing started to dip.  In the few seconds they had to understand what was happening it was too late.  The wing stalled.  The plane rolled left and pitched down.  And crashed.  Killing all 271 aboard.

Was this a design flaw?  No.  Again, it was human error.  The maintenance crew did not follow published maintenance procedures.  The left engine and pylon was replaced after routine maintenance.  The maintenance manual called for the engine removal first.  Then the engine pylon.  Some airlines were replacing the engine and pylon as an assembly.  This saved maintenance hours (and cut costs).  And was safer because it reduced the number of fuel, hydraulic and electrical wiring that had to be disconnected and reconnected.  Or so they thought.  Lifting the engine and pylon assembly to the underside of the wing attachment point was a delicate procedure, though.  That’s a lot of mass pressed against the mounting flange.  And in this case, they pushed the assembly up too high into the flange, deforming it and causing a fracture.  No one knew this as they accelerated down that O’Hare runway.  As they approached take off speed the flange broke completely, sending that engine up and over the wing.

Plane Crashes don’t help Sell Planes or Tickets

With these high-profile accidents the DC-10 got a reputation for being unsafe.  Orders fell.  While orders for the Boeing 747 remained strong.  Even though they had similar safety records.  The early 747s had 1.41 fatal accidents per PMD (the later 747-400 had 0.19 fatal accidents per PMD).  The DC-10 had 1.36 fatal accidents per PMD.  It was as safe if not safer as the 747s that were flying during the same time.  But the public relations damage was done.  Boeing sales grew.  McDonnell Douglas sales fell.  The business founded by Donald Douglas in 1921 is no more.  Unable to compete with Boeing (or Airbus) any longer, McDonnell Douglas merged with Boeing.

McDonnell Douglas had a very successful run.  But the Boeing 747 went on to dominate the wide-body market.  And one wide-body paid a lot more bills than a bunch of narrow-bodies.  Commercial planes have only gotten bigger.  The Airbus 380 is a double decker that can carry over 800 passengers.  And is giving the Boeing 747 a run for its money.  Who knows what might have happened if not for these high-profile accidents.  McDonnell Douglas had even floated the idea of a double decker airplane.  By that time, though, it was too late.

Competition between Boeing and Douglas introduced the jet age.  Their continued competition gave us wide-body jetliners.  Average people could fly anywhere in the world.  And air travel got safer through the years.  Government regulation didn’t make this happen.  Yes, the government made some planes safer.  But not until after a crash.  And they were few and far between.  The vast majority of commercial aviation flew safely.  Because manufacturers and airlines have a vested interest in being safe.  For a very good reason.  Plane crashes don’t help you sell planes.  Or tickets.  But they can put you out of business.  Even if they aren’t your fault.  Something McDonnell Douglas knows only too well.

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