Jump to content


Photo
* * * - - 2 votes

does a train use more engery than a plane as it goes faster ?


  • Please log in to reply
417 replies to this topic

#1 mariner

mariner
  • Member

  • 2,329 posts
  • Joined: January 07

Posted 30 November 2012 - 12:26

Rather off topic but prompted by the electric car thread and the plans in the UK for a high speed rail line up the spine of England. That’s controversial due to the $50B cost and environmental impacts. The argument in favour is basically capacity and faster travelling. Saving carbon has not been put forward as a justification this time which puzzled me until I read that the CO2 impact is 1.2M extra tonnes of CO2 building it and 1.8M tonnes saved over 60 years by running it. That’s not a very impressive return on "CO2 investment" so the promoters looked at ways to save more CO2. The biggest gain was by just slowing the trains down!

That got me thinking - everybody sees planes as CO2 monsters because they roar down runways etc but what many of the public don’t see is that a plane at 35,000 ft has very little drag as the air is so thin. That’s good because the thin air reduces engine power as well. Most passengers probably don’t realise that at 500mph the plane at 35,000 ft is actually quite close to staling due tot eh thin air! Less air into the engines means less fuel in and CO2 out.

So a plane has a big CO2 benefit to a train in that it can go up into a low drag zone. Also whilst regeneration is a train benefit planes sort of regen. when they glide down back to land. At a 20:1 glide slope 35,000 ft buys you 140 miles free of power (VERY simplistically).

Both a plane and a train are basically a tube full of people sitting 4 to 10 across. The tubes both create drag. Planes have the disadvantage of adding wing drag to hold them up but trains aren’t aero clean and run in ground effect surrounded by drag inducers like the power wires.

So my limited engineering physics says that as trains go faster and faster at ground level in dense air they will eventually uses more power in cruise then a plane flying up in thin air.

I know there are many variables both ways but is the basic premise true? - and if so what is the breakeven point

As a data reference Boeing claim a 747 - 800 flying London- Hong Kong at the usual load factor of 80%+ delivers 80gms/km/passenger on CO2 which actually is better than a London bus


Advertisement

#2 Ross Stonefeld

Ross Stonefeld
  • Member

  • 70,106 posts
  • Joined: August 99

Posted 30 November 2012 - 13:00

Well, except that 747(more likely to be a 777 these days) is churning through 37,000 gallons of gas. Planes aren't that efficient, but a public bus often is because they spend most of their lives nowhere near capacity.

Plus fuel can be as much as 40% of an airline's cost.

#3 jcbc3

jcbc3
  • RC Forum Host

  • 12,877 posts
  • Joined: November 04

Posted 30 November 2012 - 13:04

The energy being poured into the airplane is inevitably carbon based, whereas the train at least has the option of nuclear.

I would imagine that the TGV in France is pretty low carbon.

#4 mariner

mariner
  • Member

  • 2,329 posts
  • Joined: January 07

Posted 30 November 2012 - 13:38

yes, A TGV in France is low carbon but France is unique in its high proportion of Nuclear generation. Generally today nuclear is being shut down . e.g Germany and , to some extent all the new wind power will simply replace closed nuclear.

Obviously a plane burns a lot of fuel to go 7,000 miles London - Hong Kong and you can certianly argue that long vacation flying is evil but on the only precise basis the B747 does match a bus - thats partially load factor but trains genrally have a terrible load factor vs planes

#5 jcbc3

jcbc3
  • RC Forum Host

  • 12,877 posts
  • Joined: November 04

Posted 30 November 2012 - 13:49

well, my opinion is that we should have more nuclear and less coal based power plants.

I live in a country were we have windmills blooming all over the place (IIRC, it is claimed that more than 20% of our energy is from wind nowadays). Problem is that they are prohibitively expensive for what they generate and you still need a back-up energy source. Furthermore they are a total blight on the landscape and noisy as well.

I don't think you can compare a London bus with a transatlantic plane. It's not really apples and apples.

#6 Tenmantaylor

Tenmantaylor
  • Member

  • 18,042 posts
  • Joined: July 01

Posted 30 November 2012 - 15:32

Found a little calculator that makes the altitude/density/drag/lift relationship clearer http://www.grc.nasa....ne/density.html

It's worth noting that the drag reduction at altitude is offset by both a reduction in lift (requiring more speed to create same lift) and there isn't an engine efficiency reward to offset this (you have to burn more fuel at altitude to create the same thrust as compared to sea level). Obviously altitude has little effect on an electric motor powering the train. A diesel trains engine would run closer to it's optimal efficiency at sea level (all combustion engines do as they need air, denser the better).

I'd be surprised if a train carrying 400 people at 125mph at sea level is using more energy per person per hour than a plane carrying the same amount of people at 500mph at 50,000ft. For starters a plane needs to use full power for a significant period of time to reach high altitude in the first place.

It's possible to skew efficiency statistics (as usual) to suit a given agenda in many ways. As you point out, if you judge CO2 emissions by gram of CO2 per KM travelled per person then a boeing 747 is much more efficient than a single person driving small engined car. Yes the 747 uses a lot of fuel but it's travelling a lot of KMs and carries over 400 people at once. If you judge it by CO2 emitted per person per journey then flying by 747 is very damaging if you travel often. If a 747 burns a full tank in one journey (48,000gallons) that's 120 gallons per passenger. That is roughly 10 times the size of an the average family car's fuel tank. It would take most people 2-3 months to burn that fuel using their car. On a 747 plane they can do it in half a day! Now which is more efficient? All depends how you want to look at it.

If we want to reduce emissions the only real way to do it is to reduce how far and often we travel personally.

#7 munks

munks
  • Member

  • 428 posts
  • Joined: January 03

Posted 30 November 2012 - 15:33

Furthermore they are a total blight on the landscape ...


This is a common complaint (or excuse) against building them in the States, but aesthetically I find them nice to look at. Better than a smokestack, at least.

#8 jcbc3

jcbc3
  • RC Forum Host

  • 12,877 posts
  • Joined: November 04

Posted 30 November 2012 - 16:40

This is a common complaint (or excuse) against building them in the States, but aesthetically I find them nice to look at. Better than a smokestack, at least.


Let me say that if you make windmill farms, you can clump'em together. Preferably at sea. However, here in Denmark where we were pioneers mills are scattered all over the place when you go to a place like northern Jutland. You just can not look into any direction without seeing mills going woosh, woosh, woosh. Believe me, when you are used to and like the green rolling hills and forest and fields, they ARE a blight.

#9 Charles E Taylor

Charles E Taylor
  • Member

  • 213 posts
  • Joined: December 07

Posted 30 November 2012 - 17:04


At What Price Speed!


The Gabrielli-von Karman line. A seminal understanding.........



This work from the 1950's has been recently updated by Imperial College here.


One peek into the future for aircraft is presented by NGC here



The more you look.... the more you see.




Charlie

#10 Fat Boy

Fat Boy
  • Member

  • 2,594 posts
  • Joined: January 04

Posted 30 November 2012 - 18:35

Posted Image

#11 Catalina Park

Catalina Park
  • Member

  • 6,768 posts
  • Joined: July 01

Posted 01 December 2012 - 03:44

Furthermore they are a total blight on the landscape and noisy as well.

Visual pollution. That's the pollution that goes away when you close your eyes.

How noisy are they? Can you hear them now? Can you hear them as you drive past them? Have you ever heard one? What does it sound like?

I have worked on windfarms and I only heard them while standing directly at the base of the tower. Move about 30 metres and the noise goes away. The wind in the trees makes more noise.

#12 Kelpiecross

Kelpiecross
  • Member

  • 1,730 posts
  • Joined: October 10

Posted 01 December 2012 - 04:58

Posted Image


I may be slightly dim - but what does the picture of the dead fish mean?

#13 Kelpiecross

Kelpiecross
  • Member

  • 1,730 posts
  • Joined: October 10

Posted 01 December 2012 - 05:22

One thing that hasn't been mentioned in this plane versus train versus car debate is the convenience of the plane.

In Oz Sydney-Brisbane by plane is a bit more than one hour. By train - 14 hours. And I know from personal experience that the train is invariably full of drunken sailors or similar yobbos. (The plane can be too - but you only have to survive one hour of it).

Sydney-Perth is 5 hours by plane. Sydney-Perth by train is 3 days.

It is interesting to see the scenery by rail or road travelling from Sydney to Brisbane - but only once or twice and only if you are not in a hurry.

I have heard keen drivers who have just completed the Sydney-Perth journey say - "Never again - the trip is so long and boring it borders on being fatal".

Edited by Kelpiecross, 01 December 2012 - 05:23.


#14 Kalmake

Kalmake
  • Member

  • 4,492 posts
  • Joined: November 07

Posted 01 December 2012 - 07:14

Maglev train speeds are essentially limited only by air drag. To go faster low pressure tubes or tunnels are needed. These vactrains could go even as fast as passenger planes. The cost building tracks is too high for now though.

#15 Joe Bosworth

Joe Bosworth
  • Member

  • 686 posts
  • Joined: May 05

Posted 01 December 2012 - 09:52

Kelpie

Bad example quoting present technology for Sydney - Brisbane or Sydney - Melbourne. Oz in the backwoods for train technology; virtually guaranteeing that trains will never acheive broad use.

If we were to join the real world we would have had TGV type technology 15 or 20 years ago. Sydney - Brisbane cnentral city to central city would be less than three hours and run on time to the minute. That is effectively faster than air, more reliable and comfortable as well as cheaper.

When I travel from say Paris to London I use the train by choice and convenience. The energy footprint per passenger is also lower.

Cat, I hear quite different noise patterns than you report for wind turbines. I regulalrly paraglide at Albany WA on a ridge that has 13 wind turbines. The wump-wump sound is very noticeable at a kilometer away and the vibration noticeable at further distance. I have made my living building and operating major metals, mining and energy plants, working at decision making levels. I have learned that high energy, low frequency sounds can be quite a problem to those who live less tha about 2 km away give or take a bit depending on many factors and have always taken steps to make sure that problems are minimised. Unfortunately for low frequency sound sources there is no alternative to making sure that the owning company makes sure that they provide generous no-live zones. We sure have run some good farms around our plants.

Regards, Joe

#16 Joe Bosworth

Joe Bosworth
  • Member

  • 686 posts
  • Joined: May 05

Posted 01 December 2012 - 12:56

A quick look at emession studies related to emission/energy consumption per passenger km by transport mode provides a ready answer to the primary question of this thread.

It appears that every university, public energy or transport body in every country has studied this thing to death.

There seems to be broad agreement that any rail mode is more efficient than any aircraft mode by a factor of between about 2 and 3. This range holds true for high speed trains, heavy rail, light rail, large aircraft, small, long haul and short haul for anything approaching similar load factors.

The least efficient rail emission,energy use is still well below the most efficient air by a wide margin. The rail is also better than busses which in turn are better than auto and almost no way to get these things to cross over.

I suspect this will still hold true for the day that the auto fleet is wholly electric as rail will become either electric also and/or the turbo diesel electric efficiency is similar to power plant efficiency.

Regards

Joe

#17 jcbc3

jcbc3
  • RC Forum Host

  • 12,877 posts
  • Joined: November 04

Posted 01 December 2012 - 13:57

Visual pollution. That's the pollution that goes away when you close your eyes.


I usually close my eyes during night and have them open by day.

How noisy are they? Can you hear them now? Can you hear them as you drive past them? Have you ever heard one? What does it sound like?


43 decibels at 300 metres according to GE (first link on google search). Yes, I have heard a mill or two. I live in Denmark.


I have worked on windfarms and I only heard them while standing directly at the base of the tower. Move about 30 metres and the noise goes away. The wind in the trees makes more noise.


Look up what I said about wind farms. I think they are a good idea. Not the best because I still believe it just isn't enough to cover our energy needs.

Edited by jcbc3, 01 December 2012 - 13:58.


#18 Magoo

Magoo
  • Member

  • 3,703 posts
  • Joined: October 10

Posted 01 December 2012 - 16:06

I may be slightly dim - but what does the picture of the dead fish mean?


It's an old Sicilian message. It means George Stephenson sleeps with the fishes.

#19 Fat Boy

Fat Boy
  • Member

  • 2,594 posts
  • Joined: January 04

Posted 01 December 2012 - 16:30

It's an old Sicilian message. It means George Stephenson sleeps with the fishes.



Best in The City.

Advertisement

#20 Fat Boy

Fat Boy
  • Member

  • 2,594 posts
  • Joined: January 04

Posted 01 December 2012 - 16:40

I may be slightly dim - but what does the picture of the dead fish mean?


Red Herring.

To me, when a massive group of people fly private jets all over the world to tell me that _my_ CO2 production is the problem, they've got something else on the agenda. When the high priests and priestesses of the religion (and that's what it is) take it seriously, perhaps then I'll entertain their ideas. Until that point, however...

-------------------------------------------------

Sheriff....do the letters F.O. mean anything to you?

#21 Ross Stonefeld

Ross Stonefeld
  • Member

  • 70,106 posts
  • Joined: August 99

Posted 01 December 2012 - 18:02

Heh, I was gonna go with strung up like a kipper.

#22 Rasputin

Rasputin
  • Member

  • 960 posts
  • Joined: February 10

Posted 01 December 2012 - 19:40

Nothing beats a high-speed train from a populous city to another in any respect as long as its power comes from inexpensive nuclear-based electricity,
the problem is the investment in the railway, tunnels, bridges and what not.

But the price of crude is still way too low for anything to happen market-wise, a Barrel (159 liters) holds some 1600 kWh and costs only 100+ USD.

Go figure.

Edited by Rasputin, 01 December 2012 - 19:57.


#23 Dmitriy_Guller

Dmitriy_Guller
  • Member

  • 6,118 posts
  • Joined: July 01

Posted 02 December 2012 - 22:21

How practical is it for trains to transport cars as well? I can see trains becoming a more practical option in US if you could park your car in the train, and drive off in it at your destination.

#24 jcbc3

jcbc3
  • RC Forum Host

  • 12,877 posts
  • Joined: November 04

Posted 02 December 2012 - 22:48

Happens already in Europe

Posted Image

#25 saudoso

saudoso
  • Member

  • 6,776 posts
  • Joined: March 04

Posted 02 December 2012 - 22:52

EDIT: Ooops, jcbc3 got it here first.
http://www.seat61.com/Motorail.htm



On the subject of the original question, I fail to see how hauling something 10Km into the sky and dragging it around 3 times the speed can be any more energy efficient by any means.

Unless, off course, you push it high enough to get it into orbit and running on zero gravity and drag forever.

Edited by saudoso, 02 December 2012 - 23:05.


#26 Dmitriy_Guller

Dmitriy_Guller
  • Member

  • 6,118 posts
  • Joined: July 01

Posted 02 December 2012 - 23:17

Interesting. It doesn't seem that well-developed though. Maybe demand is not high, or it's prohibitively expensive.

#27 bigleagueslider

bigleagueslider
  • Member

  • 1,235 posts
  • Joined: March 11

Posted 03 December 2012 - 00:22

On the subject of the original question, I fail to see how hauling something 10Km into the sky and dragging it around 3 times the speed can be any more energy efficient by any means. Unless, off course, you push it high enough to get it into orbit and running on zero gravity and drag forever.


Energy efficiency is only a secondary concern in most of the developed world when it comes to modern modes of commercial passenger travel. Sure, rail uses less energy per passenger-mile than commercial jet, and it costs less in most instances. But commercial jet is far faster over long distances, and is currently statistically safer than rail travel. Here in the US, it would take 70 hours and cost over $400 to travel from LA to NY on Amtrak. The same trip by commercial jet would take around 6 hours and cost about $350.

Regarding the question posed by the OP, assuming the same speeds, I would guess that a modern commercial jet would be more efficient than a diesel-electric train. The jet flies a more direct route than the train, and can even take advantage of prevailing high-speed wind currents in the atmosphere. Plus the jet is far lighter than the train.

#28 Lee Nicolle

Lee Nicolle
  • Member

  • 11,038 posts
  • Joined: July 08

Posted 03 December 2012 - 09:16

Visual pollution. That's the pollution that goes away when you close your eyes.

How noisy are they? Can you hear them now? Can you hear them as you drive past them? Have you ever heard one? What does it sound like?

I have worked on windfarms and I only heard them while standing directly at the base of the tower. Move about 30 metres and the noise goes away. The wind in the trees makes more noise.

Michael, are you doing adverts for wind farms now? I have had a look through several and they are not really quiet. Wind in the trees can be noisier,, but not in light breeze. And the occasional big 'clunks' make me want to run away. And I have heard them in several windfarms.

#29 Lee Nicolle

Lee Nicolle
  • Member

  • 11,038 posts
  • Joined: July 08

Posted 03 December 2012 - 09:23

How practical is it for trains to transport cars as well? I can see trains becoming a more practical option in US if you could park your car in the train, and drive off in it at your destination.

People have been doing that for decades in Oz. My father drove to Perth and trained the whole lot home. Ditto for Darwin. A mate drives to Darwin every year as a rep, then flys home and packs his orders and picks his ute up later in the week from the train. And quite a few others do similar.
And as others have said the plane is so much quicker, time is money. Trains are good for leisure, a plane makes the same trip a commute. And in this country at least it is cheaper to fly than catch a bloody train anyway. In the past it was different but not these days.

#30 Kalmake

Kalmake
  • Member

  • 4,492 posts
  • Joined: November 07

Posted 03 December 2012 - 14:42

On the subject of the original question, I fail to see how hauling something 10Km into the sky and dragging it around 3 times the speed can be any more energy efficient by any means.


But it is so, if we need to go as fast as a jet plane. Which was the point in OP, I think.

777 cruises at 11km at 905km/h, because air density is less than 1/4 of sea level. Currently, only thing that goes faster than that on land is ThrustSSC*, but it uses more power and has only one seat!

It's not possible to build a passenger train with low enough drag to make 900km/h sensible. The expensive trick of lowering air density is a must.

There are (boring) factors that help trains like electric engine efficiency vs combustion, greener energy source vs fossil, regenerative braking.... but it's not enough to beat the mighty equation at those speeds:

Power required to overcome aero drag = 1/2 * air density * drag coefficient * frontal area * velocity^3


*They are actually planning to beat low altitude plane records which are limited by structural strength issues (wings fall off).

#31 Fat Boy

Fat Boy
  • Member

  • 2,594 posts
  • Joined: January 04

Posted 03 December 2012 - 16:57

Nothing beats a high-speed train from a populous city to another in any respect as long as its power comes from inexpensive nuclear-based electricity,
the problem is the investment in the railway, tunnels, bridges and what not.

But the price of crude is still way too low for anything to happen market-wise, a Barrel (159 liters) holds some 1600 kWh and costs only 100+ USD.

Go figure.



As long as those cities are a relatively close together. The California plan between LA and SF is absurd.

#32 Charles E Taylor

Charles E Taylor
  • Member

  • 213 posts
  • Joined: December 07

Posted 03 December 2012 - 17:38

True Costs

When considering differing modes of transport it is easy to dismiss the true cost of the infrastructure.

When the infrastructure costs, particularly the upkeep are considered……. Well.

Not much beats the amphibious aircraft, particularly those that can land on un-improved airfields. Go anywhere... well nearly!

An amphibious, powered, glider?... Now there's a thought

http://www.nasa.gov/...tion/index.html


I wish I had one.





Charlie


#33 saudoso

saudoso
  • Member

  • 6,776 posts
  • Joined: March 04

Posted 03 December 2012 - 20:00

On the train issue, I've got small experience with them. I did use high speed trains between Roma/Milano Roma/Napoles and Frankfurt/Berlin.

Any train travel less than 3 hours is worth the hassle over a short flight, even if it's more expensive. Just keeping the shoes on and leaving/arriving downtown sufuce for me. And then there is comfort during the trip.

#34 Ross Stonefeld

Ross Stonefeld
  • Member

  • 70,106 posts
  • Joined: August 99

Posted 03 December 2012 - 21:06

Yeah, they're definitely not competing with planes over a certain time/distance. You compare public transport to cars. And for things like daily commutes I far prefer rail. I love driving cars, but as a day to day thing a half hour reading a newspaper or talking to someone I know is better than following some guy at 45mph or sitting in traffic.

The bus kind of sucks though.

#35 desmo

desmo
  • Tech Forum Host

  • 29,392 posts
  • Joined: January 00

Posted 03 December 2012 - 21:57

I agree about buses but why? Is it simply because they tend to be downmarket? The seats are never as nice or as roomy, they never seem to have have W-Fi or power outlets, seldom have WCs onboard. There is really little intrinsic reason I can see for buses not to be as nice to ride as trains, it seems like they just aren't trying.

#36 Ross Stonefeld

Ross Stonefeld
  • Member

  • 70,106 posts
  • Joined: August 99

Posted 03 December 2012 - 22:04

The bus is fine for short trips, especially in a European city where they're a bit better. The bus in America tends to be very downmarket so maybe that's why you have the examples you talk about. All sorts of people take the bus in say, London.

But it has the downside of the car that you can get stuck in traffic. Trains have their problems but on a bus you're guaranteed to have a dramatically slower journey time at either end of the day.



#37 Tony Matthews

Tony Matthews
  • Member

  • 17,519 posts
  • Joined: September 08

Posted 03 December 2012 - 22:38

I agree about buses but why? Is it simply because they tend to be downmarket? The seats are never as nice or as roomy, they never seem to have have W-Fi or power outlets, seldom have WCs onboard.

Dunno about wi-fi, but intercity coaches invariably have toilets, comfy seats and are generally pretty smart.

#38 Grumbles

Grumbles
  • Member

  • 326 posts
  • Joined: September 09

Posted 04 December 2012 - 00:05

Any train travel less than 3 hours is worth the hassle over a short flight, even if it's more expensive. Just keeping the shoes on and leaving/arriving downtown sufuce for me. And then there is comfort during the trip.


I hate flying. I hate being packed in like sardines, I hate the security farce, I hate all those passengers who bring along everything they own up to and including a grand piano as carry-on luggage. And then climb all over you so they can rearrange said luggage. I'd much rather drive all day than sit next to some fat smelly bastard working on his stupid powerpoint presentation.


#39 Lee Nicolle

Lee Nicolle
  • Member

  • 11,038 posts
  • Joined: July 08

Posted 04 December 2012 - 09:29

Buses and trains in the metro area should all conform to passenger vehicle standards, and everybody should have a seat belt, attached to a proper seat. not a steel framed canvas chair. And the vehicle should not move until everybody is seated and belted. That includes babys and children to the approprite standards.
Cattle class especially on a bus is lunacy, and when the accident happens it is always someone elses fault! Not the operator of the death trap.
Wont happen, ban them and get in your car that does have to comply. And doesnt stop every kilometre to pick up more people to be sardined in.
And passenger coaches while better and generally have proper seats and belts are still a major compromise in impact resistance and often basic stability. 2 story vehicles on little more than a truck chassis.

Advertisement

#40 Wuzak

Wuzak
  • Member

  • 8,416 posts
  • Joined: September 00

Posted 04 December 2012 - 10:17

But it is so, if we need to go as fast as a jet plane. Which was the point in OP, I think.

777 cruises at 11km at 905km/h, because air density is less than 1/4 of sea level. Currently, only thing that goes faster than that on land is ThrustSSC*, but it uses more power and has only one seat!

It's not possible to build a passenger train with low enough drag to make 900km/h sensible. The expensive trick of lowering air density is a must.

There are (boring) factors that help trains like electric engine efficiency vs combustion, greener energy source vs fossil, regenerative braking.... but it's not enough to beat the mighty equation at those speeds:

Power required to overcome aero drag = 1/2 * air density * drag coefficient * frontal area * velocity^3


*They are actually planning to beat low altitude plane records which are limited by structural strength issues (wings fall off).



Lowering the air density also lowers the Mach number, which also affects the efficiency. Lower air density also affects the efficiency of the engines, which aren't anywhere near as efficient as a railway Diesel-electric or electric system.




#41 Wuzak

Wuzak
  • Member

  • 8,416 posts
  • Joined: September 00

Posted 04 December 2012 - 10:21

As long as those cities are a relatively close together. The California plan between LA and SF is absurd.


How so?

The distance between the two appears (from a quick search) to be less than 600km. That is closer than Melbourne-Sydney. That should mean a journey of about 2 hours on a high speed train.

I did that journey on Amtrak in 2006, which took (with intermediate stops) about 10-12 hours (can't recall exactly).

#42 Wuzak

Wuzak
  • Member

  • 8,416 posts
  • Joined: September 00

Posted 04 December 2012 - 10:26

yes, A TGV in France is low carbon but France is unique in its high proportion of Nuclear generation. Generally today nuclear is being shut down . e.g Germany and , to some extent all the new wind power will simply replace closed nuclear.

Obviously a plane burns a lot of fuel to go 7,000 miles London - Hong Kong and you can certianly argue that long vacation flying is evil but on the only precise basis the B747 does match a bus - thats partially load factor but trains genrally have a terrible load factor vs planes


I would say that commuter trains would have low load factors vs trains, but city to city trains? Another issue with that is when a load factor occurs in a scheduled flight they cancel the flight. Not the case with trains.

I assume that by "load factor" you are referring to the percentage of passengers vs capacity?



#43 Wuzak

Wuzak
  • Member

  • 8,416 posts
  • Joined: September 00

Posted 04 December 2012 - 10:44

People have been doing that for decades in Oz. My father drove to Perth and trained the whole lot home. Ditto for Darwin. A mate drives to Darwin every year as a rep, then flys home and packs his orders and picks his ute up later in the week from the train. And quite a few others do similar.
And as others have said the plane is so much quicker, time is money. Trains are good for leisure, a plane makes the same trip a commute. And in this country at least it is cheaper to fly than catch a bloody train anyway. In the past it was different but not these days.


The plane is so much quicker...in some circumstances - such as with longer distances - eg Sydney-Perth.

Not necessarily with shorter trips from Sydney to Melbourne, for instance.

The Sydney airport is located near the centre of the city. I am not sure how long it would take to get to the CBD from there. In Melbourne the main airport is some way out from the CBD. At certain times of the day it can take an hour, or more, to get from the airport to the CBD. Then there is the requirement to be early so you can check bags, go through security, load the plane up (which seems to take longer these days), the trip from the gate to the runway (which can sometimes seem forever!), waiting for other aircraft in the queue to take-off or land. Time soon adds up.

Meanwhile, the existing rail structure goes, essentially from CBD to CBD. This infrastructure could largely be used for high speed TGV style trains - the lines between would need to be altered (they aren't suitable for high speed work, apparently).

The government has again been looking to push for a Melbourne-Canberra-Sydney-Brisbane fast train network. If that gets the go ahead it could reduce patronage to the airlines. which would also drive up airline prices.

Also, consider that Sydney airport is nearing capacity, which is why there have been studies into a second international airport. But nobody wants that in their back yard. Reduce the domestic load on Sydney airport and mabe the second one isn't required.

#44 Wuzak

Wuzak
  • Member

  • 8,416 posts
  • Joined: September 00

Posted 04 December 2012 - 11:12

I have just returned from the US. The last few days I spent in Huntington Beach, south of LA. A map in the hotel info pack showed a driving time to LAX of around 45 minutes (which, I suppose, it was at 8:00pm on a Sunday evening!). But everything seems to take considerably longer.

A friend drove over from his place to pick me up for a day trip to San Diego last Thursday. He left at 7:00am and arrived somewhat after 10:00am. The drive was supposed to take 90 minutes. The drive to and from San Diego seemed to go smoothly enough. But the experience didn't agree with my friend, so we agreed to meet halfway. That meant bus and/or taxi ride to train station and a train ride for me. Check the bus schedules - it would take approximately 2.5 hours and 4 buses to get to the train station. So, I got a cab. That took an hour and a $50 fare. Got on the train, for an hour's ride. Then drive for another hour to get to where we were going.

On the train on the way back I noticed as we crossed a 6 lane freeway (as in 6 one way, and 6 the other - should that be a 12 lane freeway?) that not one car was moving - thousands of red lights on one side, and thousands of white lights on the other. Motionless. Is this the freedom of the car?

Also, spent some time in Texas. They seem to have become builders of great multi-level spaghetti intersections. More than once I was driven over on a 3rd or 4th level overpass/exit. Each with safety barriers lower than the window line on our car (modern Dodge Charger). Apparently one motorcyclist had already managed to launch himself over the side. My first though upon seeing one of these vast overpass systems was "this is nuts".

Posted Image

#45 saudoso

saudoso
  • Member

  • 6,776 posts
  • Joined: March 04

Posted 04 December 2012 - 11:24

Let alone negotiating the carpool lanes and their exclusive overpasses. An endless thrill when you are a tourist, GPS or not.

#46 Wuzak

Wuzak
  • Member

  • 8,416 posts
  • Joined: September 00

Posted 04 December 2012 - 11:56

Let alone negotiating the carpool lanes and their exclusive overpasses. An endless thrill when you are a tourist, GPS or not.


The car pool lanes I saw in California did not have their own exits. To exit you would have to leave the carpool lane in areas where you are allowed (not that frequent) and then move 3, 4 or 5 lanes over to the right to get to the exit.

#47 saudoso

saudoso
  • Member

  • 6,776 posts
  • Joined: March 04

Posted 04 December 2012 - 13:09

There are many points around LA where the carpool lane will go into a single lane overpass. If memory serves me right driving from Hollywood to LAX there are two of such detours. It's kind of nerve wrecking when you drive to the airport and the carpool lane is indeed faster but you're not sure the overpass will keep you from taking a needed exit.



#48 Dmitriy_Guller

Dmitriy_Guller
  • Member

  • 6,118 posts
  • Joined: July 01

Posted 04 December 2012 - 15:03

Buses and trains in the metro area should all conform to passenger vehicle standards, and everybody should have a seat belt, attached to a proper seat. not a steel framed canvas chair. And the vehicle should not move until everybody is seated and belted. That includes babys and children to the approprite standards.
Cattle class especially on a bus is lunacy, and when the accident happens it is always someone elses fault! Not the operator of the death trap.
Wont happen, ban them and get in your car that does have to comply. And doesnt stop every kilometre to pick up more people to be sardined in.
And passenger coaches while better and generally have proper seats and belts are still a major compromise in impact resistance and often basic stability. 2 story vehicles on little more than a truck chassis.

So mass transit must have terrible deaths per mile statistics compared to cars, right?

#49 sweetreid

sweetreid
  • Member

  • 45 posts
  • Joined: November 05

Posted 04 December 2012 - 16:26

So a plane has a big CO2 benefit to a train in that it can go up into a low drag zone. Also whilst regeneration is a train benefit planes sort of regen. when they glide down back to land. At a 20:1 glide slope 35,000 ft buys you 140 miles free of power (VERY simplistically).


Planes don't start from 35k ft. It takes a tremendous amount of power to keep the plane at speed during the ascend. During the ascend it has to put up with the same thick air as a train, while it is going much faster (and thus creating proportionally more drag). Planes create drag that a train could never reach during ascend.

Planes also don't idle their engines under any circumstances for safety reasons. It's not as simple as a car going down a hill with the engine in gear. The engines are always powered and consuming fuel, because they need to be ready to provide a tremendous amount of thrust immediately in order to abort a landing.

Also there is another problem, a plane needs to travel over 200 miles (assuming 60 miles for ascend, 140 miles to descend) to even reach it's cruising altitude. If you want to use planes to replace rail, then you need to consider the places that are 100 miles or more from your origin and destination. You will add at least 100 miles of travel to these places. People will need to get on a bus, which will waste lots of time (already having wasted extra time waiting for takeoff and landing rights, which are hugely influenced by bad weather), and emit additional CO2.


#50 Fat Boy

Fat Boy
  • Member

  • 2,594 posts
  • Joined: January 04

Posted 04 December 2012 - 19:24

How so?

The distance between the two appears (from a quick search) to be less than 600km. That is closer than Melbourne-Sydney. That should mean a journey of about 2 hours on a high speed train.

I did that journey on Amtrak in 2006, which took (with intermediate stops) about 10-12 hours (can't recall exactly).



I've taken the Amtrak on that ride as well. It's great. For about $400 my wife and I spent a great day rolling up the coast. However, the economics don't support it for everyday travel. I can fly for $100 or so and get there in, what, 1 1/2 hours?

The new high speed rail program will take about 4 hours (at best...it will probably take longer...it's anything but a straight line path, probably 800km). It has been independently estimated at $100 Billion total cost. It will probably run more than that. It was sold to the voters at a $35B total cost. Now understand that California has the same basic economic situation as Greece. So who is paying for this? Environmentalists and farmers are very unhappy with the land effects of building it. Oh ya, they estimate that the cost to ride the train from LA to SF (in present day dollars) will cost over $200.

So the high speed rail costs a massive chunk of money, it's slower than a plane, it's more expensive than a plane and it tears up the environment. What's the logic here, again?