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Central line to be converted to AC?
It sounds like an April Fools joke but apparently TfL are considering
it. http://tinyurl.com/5augle Presumably if this were to go ahead the line would have to be closed for an extended period. Peter Smyth |
Central line to be converted to AC?
On 19 Apr, 11:30, "Peter Smyth" wrote:
It sounds like an April Fools joke but apparently TfL are considering it.http://tinyurl.com/5augle Presumably if this were to go ahead the line would have to be closed for an extended period. It refers to AC motors, which are more efficient than DC motors. AC motors are driven by chopping up DC power electronically to match the desired rotation speed, so there's no need to have the traction current be AC. The Jubilee and Northern stock already has AC motors, as do Networkers and most if not all newer EMUs. U -- http://londonconnections.blogspot.com/ A blog about transport projects in London |
Central line to be converted to AC?
In message , at 11:30:49 on Sat,
19 Apr 2008, Peter Smyth remarked: It sounds like an April Fools joke but apparently TfL are considering it. http://tinyurl.com/5augle Presumably if this were to go ahead the line would have to be closed for an extended period. And would the AC motors fall off the bogies less often than the DC ones? -- Roland Perry |
Central line to be converted to AC?
In article ,
Peter Smyth wrote: It sounds like an April Fools joke but apparently TfL are considering it. http://tinyurl.com/5augle I'm not sure why you think it might be a april fools joke: both the '95 and '96 stock have AC traction packages. Presumably if this were to go ahead the line would have to be closed for an extended period. Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. -- Shenanigans! Shenanigans! Best of 3! -- Flash |
Central line to be converted to AC?
On Sat, 19 Apr 2008, Mike Bristow wrote:
In article , Peter Smyth wrote: It sounds like an April Fools joke but apparently TfL are considering it. http://tinyurl.com/5augle I'm not sure why you think it might be a april fools joke: both the '95 and '96 stock have AC traction packages. Presumably if this were to go ahead the line would have to be closed for an extended period. Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. I think Peter thought, as i did, that this meant converting the power supply to AC. Possibly by somehow stringing up cables in the tunnels. Which does sound like it could take a while. tom -- But for [Flavor Flav's] "YEAAAAAAAAAAAAAH BOYYYYYYYYYY"s alone he should be given Rap Legend status. -- Nate Patrin, ILX |
Central line to be converted to AC?
"Mr Thant" wrote in message ... On 19 Apr, 11:30, "Peter Smyth" wrote: It sounds like an April Fools joke but apparently TfL are considering it.http://tinyurl.com/5augle Presumably if this were to go ahead the line would have to be closed for an extended period. It refers to AC motors, which are more efficient than DC motors. AC motors are driven by chopping up DC power electronically to match the desired rotation speed, so there's no need to have the traction current be AC. The Jubilee and Northern stock already has AC motors, as do Networkers and most if not all newer EMUs. Thanks - it makes a lot more sense now. Peter Smyth |
Central line to be converted to AC?
Tom Anderson wrote:
I think Peter thought, as i did, that this meant converting the power supply to AC. Possibly by somehow stringing up cables in the tunnels. Which does sound like it could take a while. .... but was planned for the Victoria Line a few years ago. |
Central line to be converted to AC?
Tom Anderson wrote:
I think Peter thought, as i did, that this meant converting the power supply to AC. And here I was thinking they were going to air condition the Central Line... |
Central line to be converted to AC?
On 19 Apr, 16:36, "John Rowland"
wrote: Tom Anderson wrote: I think Peter thought, as i did, that this meant converting the power supply to AC. Possibly by somehow stringing up cables in the tunnels. Which does sound like it could take a while. ... but was planned for the Victoria Line a few years ago. The space train I want one. A missed oppertunity if there ever was one. |
Central line to be converted to AC?
On 19 Apr, 16:36, "John Rowland" wrote: Tom Anderson wrote: I think Peter thought, as i did, that this meant converting the power supply to AC. Possibly by somehow stringing up cables in the tunnels. Which does sound like it could take a while. ... but was planned for the Victoria Line a few years ago. Really? When was this, how close did it come to happening, etc? |
Central line to be converted to AC?
On 21 Apr, 09:04, Mizter T wrote:
I think Peter thought, as i did, that this meant converting the power supply to AC. Possibly by somehow stringing up cables in the tunnels. Which does sound like it could take a while. ... but was planned for the Victoria Line a few years ago. Really? When was this, how close did it come to happening, etc? About five years ago, and not very. http://www.coroflot.com/public/indiv...dual_id=115892 -- John Band john at johnband dot org www.johnband.org |
Central line to be converted to AC?
Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. If they do it lets hope they don't reduce the performance of the central line trains to the slug like performance of the northern line ones. The central trains are the only ones on the tube that have anything approaching the decent acceleration that you'd expect on a modern metro. B2003 |
Central line to be converted to AC?
At 03:06:46 on Mon, 21 Apr 2008 Boltar opined:-
Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. If they do it lets hope they don't reduce the performance of the central line trains to the slug like performance of the northern line ones. The central trains are the only ones on the tube that have anything approaching the decent acceleration that you'd expect on a modern metro. Is that because of the trains or because on the tube sections acceleration is aided by gravity? -- Thoss |
Central line to be converted to AC?
"thoss" wrote in message ... At 03:06:46 on Mon, 21 Apr 2008 Boltar opined:- Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. If they do it lets hope they don't reduce the performance of the central line trains to the slug like performance of the northern line ones. The central trains are the only ones on the tube that have anything approaching the decent acceleration that you'd expect on a modern metro. Is that because of the trains or because on the tube sections acceleration is aided by gravity? It is because the Central line has full automatic train operation (ATO), which for normal day to day use drives the trains nearer the limits than manual driving can. There is no reason why a change from DC to AC traction would make performance worse, in fact it ought to improve AFAICT. Paul S |
Central line to be converted to AC?
Paul Scott wrote: It is because the Central line has full automatic train operation (ATO), which for normal day to day use drives the trains nearer the limits than It can't be just that surely. Even on the long open stretches outside where the drivers could give it some welly the northern trains still chug along at a leisurely pace and take their time getting to it. Perhaps the whole line has a low linespeed now, dunno. B2003 |
Central line to be converted to AC?
On 21 Apr, 11:39, "Paul Scott" wrote: "thoss" wrote: At 03:06:46 on Mon, 21 Apr 2008 Boltar opined:- Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. If they do it lets hope they don't reduce the performance of the central line trains to the slug like performance of the northern line ones. The central trains are the only ones on the tube that have anything approaching the decent acceleration that you'd expect on a modern metro. Is that because of the trains or because on the tube sections acceleration is aided by gravity? It is because the Central line has full automatic train operation (ATO), which for normal day to day use drives the trains nearer the limits than manual driving can. There is no reason why a change from DC to AC traction would make performance worse, in fact it ought to improve AFAICT. Indeed - it's all about the ATO. |
Central line to be converted to AC?
On Apr 21, 12:46*pm, Mizter T wrote:
On 21 Apr, 11:39, "Paul Scott" wrote: "thoss" wrote: At 03:06:46 on Mon, 21 Apr 2008 Boltar opined:- Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. * It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. If they do it lets hope they don't reduce the performance of the central line trains to the slug like performance of the northern line ones. The central trains are the only ones on the tube that have anything approaching the decent acceleration that you'd expect on a modern metro. Is that because of the trains or because on the tube sections acceleration is aided by gravity? It is because the Central line has full automatic train operation (ATO), which for normal day to day use drives the trains nearer the limits than manual driving can. *There is no reason why a change from DC to AC traction would make performance worse, in fact it ought to improve AFAICT. Indeed - it's all about the ATO. There is also the fact that all axles are motored on the Central line's 1992 stock, whilst the Northern line's 1995 stock has two trailer cars per 6 car unit. This means that the '92 stock is lighter (per car). Having every axle motored generally allows better acceleration, if all other things are equal. It will be interesting to see how the Northern stock performs, once the trains are used to their full potential. |
Central line to be converted to AC?
On 21 Apr, 13:55, Andy wrote: On Apr 21, 12:46 pm, Mizter T wrote: On 21 Apr, 11:39, "Paul Scott" wrote: "thoss" wrote: At 03:06:46 on Mon, 21 Apr 2008 Boltar opined:- Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. If they do it lets hope they don't reduce the performance of the central line trains to the slug like performance of the northern line ones. The central trains are the only ones on the tube that have anything approaching the decent acceleration that you'd expect on a modern metro. Is that because of the trains or because on the tube sections acceleration is aided by gravity? It is because the Central line has full automatic train operation (ATO), which for normal day to day use drives the trains nearer the limits than manual driving can. There is no reason why a change from DC to AC traction would make performance worse, in fact it ought to improve AFAICT. Indeed - it's all about the ATO. There is also the fact that all axles are motored on the Central line's 1992 stock, whilst the Northern line's 1995 stock has two trailer cars per 6 car unit. This means that the '92 stock is lighter (per car). Having every axle motored generally allows better acceleration, if all other things are equal. It will be interesting to see how the Northern stock performs, once the trains are used to their full potential. Though, speaking from a position of total ignorance here, might the motors on the Northern line trains be more powerful, thus less are needed? |
Central line to be converted to AC?
Peter Smyth wrote:
It sounds like an April Fools joke but apparently TfL are considering it. http://tinyurl.com/5augle Presumably if this were to go ahead the line would have to be closed for an extended period. "Range: between 90 000 000 and 130 000 000 GBP." 'Ow much?!?!?! -- http://www.railforums.co.uk |
Central line to be converted to AC?
On 21 Apr, 17:36, Joe Patrick
wrote: It sounds like an April Fools joke but apparently TfL are considering it. http://tinyurl.com/5augle Presumably if this were to go ahead the line would have to be closed for an extended period. "Range: between 90 000 000 and 130 000 000 GBP." 'Ow much?!?!?! That's GBP1-1.5m per train, or GBP150-200k per carriage. Doesn't sounds a million miles out... -- John Band john at johnband dot org www.johnband.org |
Central line to be converted to AC?
In message
, at 09:52:48 on Mon, 21 Apr 2008, John B remarked: "Range: between 90 000 000 and 130 000 000 GBP." 'Ow much?!?!?! That's GBP1-1.5m per train, or GBP150-200k per carriage. Doesn't sounds a million miles out... For a couple of electric motors!!!! -- Roland Perry |
Central line to be converted to AC?
On 21 Apr, 13:55, Andy wrote:
(per car). Having every axle motored generally allows better acceleration, if all other things are equal. It will be interesting to see how the Northern stock performs, once the trains are used to their full potential. Why arn't they using it already, what are they waiting for? The A stock was doing 60 mph back in the 1960s with no ATO in sight. B2003 |
Central line to be converted to AC?
On 21 Apr, 18:10, Roland Perry wrote:
That's GBP1-1.5m per train, or GBP150-200k per carriage. Doesn't sounds a million miles out... For a couple of electric motors!!!! About 10% of the cost of a new carriage to replace the whole drive system? Sounds pretty reasonable to me... -- John Band john at johnband dot org www.johnband.org |
Central line to be converted to AC?
In message
, at 10:17:34 on Mon, 21 Apr 2008, John B remarked: That's GBP1-1.5m per train, or GBP150-200k per carriage. Doesn't sounds a million miles out... For a couple of electric motors!!!! About 10% of the cost of a new carriage to replace the whole drive system? Sounds pretty reasonable to me... Why "the whole drive system" ? I still think GBP50K for an electric motor is a bit steep. -- Roland Perry |
Central line to be converted to AC?
On 21 Apr, 18:30, Roland Perry wrote:
In message , at 10:17:34 on Mon, 21 Apr 2008, John B remarked: That's GBP1-1.5m per train, or GBP150-200k per carriage. Doesn't sounds a million miles out... For a couple of electric motors!!!! About 10% of the cost of a new carriage to replace the whole drive system? Sounds pretty reasonable to me... Why "the whole drive system" ? I still think GBP50K for an electric motor is a bit steep. You can't run AC motors using electronics designed for a DC system. Though why they feel the need to change the traction package on perfectly servicable still fairly new trains is another matter. I can't imagine them saving 100M in electricity bills before thr trains are life expired. B2003 |
Central line to be converted to AC?
On 21 Apr, 18:58, Boltar wrote:
You can't run AC motors using electronics designed for a DC system. Though why they feel the need to change the traction package on perfectly servicable still fairly new trains is another matter. I can't imagine them saving 100M in electricity bills before thr trains are life expired. Basically, because the DC motors weren't very reliable in the first place and are now apparently completely f***ed - the choice isn't "leave them or replace with AC", it's "persuade someone to build new obsolete-but-not-knackered DC motors or replace with AC". -- John Band john at johnband dot org www.johnband.org |
Central line to be converted to AC?
On 21 Apr, 19:37, John B wrote:
Basically, because the DC motors weren't very reliable in the first place and are now apparently completely f***ed - the choice isn't "leave them or replace with AC", it's "persuade someone to build new obsolete-but-not-knackered DC motors or replace with AC". If they're knackered already I wonder if they can get compensation from the manufacturers (assuming they're still around) since I'm pretty sure the design lifetime must have been lot more than 12 or so years. B2003 |
Central line to be converted to AC?
On Apr 21, 10:44 pm, Boltar wrote:
Basically, because the DC motors weren't very reliable in the first place and are now apparently completely f***ed - the choice isn't "leave them or replace with AC", it's "persuade someone to build new obsolete-but-not-knackered DC motors or replace with AC". If they're knackered already I wonder if they can get compensation from the manufacturers (assuming they're still around) since I'm pretty sure the design lifetime must have been lot more than 12 or so years. The trains were built by ABB/Adtranz (now Bombardier), but the traction system was built by Brush. I've no idea how the legal liability trail would work, or whether a court would hold that a 15- year lifespan for the motors was unreasonable... -- John Band john at johnband dot org www.johnband.org |
Central line to be converted to AC?
On 21 Apr, 23:42, John B wrote: On Apr 21, 10:44 pm, Boltar wrote: Basically, because the DC motors weren't very reliable in the first place and are now apparently completely f***ed - the choice isn't "leave them or replace with AC", it's "persuade someone to build new obsolete-but-not-knackered DC motors or replace with AC". If they're knackered already I wonder if they can get compensation from the manufacturers (assuming they're still around) since I'm pretty sure the design lifetime must have been lot more than 12 or so years. The trains were built by ABB/Adtranz (now Bombardier), but the traction system was built by Brush. I've no idea how the legal liability trail would work, or whether a court would hold that a 15- year lifespan for the motors was unreasonable... Perhaps LU compromised somewhat on the motors? |
Central line to be converted to AC?
On Apr 21, 6:11*pm, Boltar wrote:
On 21 Apr, 13:55, Andy wrote: (per car). Having every axle motored generally allows better acceleration, if all other things are equal. It will be interesting to see how the Northern stock performs, once the trains are used to their full potential. Why arn't they using it already, what are they waiting for? The A stock was doing 60 mph back in the 1960s with no ATO in sight. B2003 Basically because the signalling can't cope. Thing's like stopping distances and overlaps are set up for the 1959 stock. A 1995 stock train approaching a signal more quickly than a 1959 stock train leads to potential problems with the overlap distances; as does accelerating more quickly from a platform. The original plan was for a replacement of the trains to be followed immediately by replacement of the signalling. However, the money for the signalling and track upgrade was cut, leading to new trains which had to be detuned to run safely on old signalling setup. What I don't know is if the 1996 on the Jubilee line is also detuned compared to maximum performance, awaiting introduction of new signalling, or whether the history of most of the line being part of the Metropolitan means that the signalling is better setup for 'mainline' performance. |
Central line to be converted to AC?
On Apr 21, 4:16*pm, Mizter T wrote:
On 21 Apr, 13:55, Andy wrote: On Apr 21, 12:46 pm, Mizter T wrote: On 21 Apr, 11:39, "Paul Scott" wrote: "thoss" wrote: At 03:06:46 on Mon, 21 Apr 2008 Boltar opined:- Change the traction package on a unit, and put it back in service. Don't see why that would require closing the line. * It might not be possible to couple a DC unit and an AC unit in a single train, but they can certainly share the same track and power rails. If they do it lets hope they don't reduce the performance of the central line trains to the slug like performance of the northern line ones. The central trains are the only ones on the tube that have anything approaching the decent acceleration that you'd expect on a modern metro. Is that because of the trains or because on the tube sections acceleration is aided by gravity? It is because the Central line has full automatic train operation (ATO), which for normal day to day use drives the trains nearer the limits than manual driving can. *There is no reason why a change from DC to AC traction would make performance worse, in fact it ought to improve AFAICT. Indeed - it's all about the ATO. There is also the fact that all axles are motored on the Central line's 1992 stock, whilst the Northern line's 1995 stock has two trailer cars per 6 car unit. This means that the '92 stock is lighter (per car). Having every axle motored generally allows better acceleration, if all other things are equal. It will be interesting to see how the Northern stock performs, once the trains are used to their full potential. Though, speaking from a position of total ignorance here, might the motors on the Northern line trains be more powerful, thus less are needed? Indeed they are, but the problem is more putting the power to the track. The size of the wheels on tube stock means that best performance was gained by using small, less powerful (DC) motors under the cars in the 1992 stock and powering every axle. By the time that the 1995/6 stock came along, the AC motors became suited to the task and these are more powerful for their size than the DC ones. I think that when the 1992 stock was being designed, there was no motor powerful enough to both fit under the cars and give the desired output per train, without having every axle powered. There is also the consideration of adhesion. Having more axles powered spreads the 'push' out and gives less chance of wheelslip etc., when it is wet or icey. |
Central line to be converted to AC?
In message
, Boltar writes Why arn't they using it already, what are they waiting for? The A stock was doing 60 mph back in the 1960s with no ATO in sight. So was 62 stock on the Central line, but it was not authorised for use in tunnel sections. -- Clive |
Central line to be converted to AC?
On 21 Apr, 18:17, John B wrote:
On 21 Apr, 18:10, Roland Perry wrote: That's GBP1-1.5m per train, or GBP150-200k per carriage. Doesn't sounds a million miles out... For a couple of electric motors!!!! About 10% of the cost of a new carriage to replace the whole drive system? Sounds pretty reasonable to me... Are Underground carriages really about GBP 1.5m-2m? I thought recent- ish DC electric surface stock (e.g. the 450s on SWT) came in at about GBP 1m per carriage, and for that you get motors, brakes and crashworthiness suitable for 100MPH running, aircon, PIS and toilets! Steve Adams |
Cost of new rail carriages (was Central line to be converted toAC?)
On Apr 22, 9:57 pm, Steve wrote:
Are Underground carriages really about GBP 1.5m-2m? I thought recent- ish DC electric surface stock (e.g. the 450s on SWT) came in at about GBP 1m per carriage, and for that you get motors, brakes and crashworthiness suitable for 100MPH running, aircon, PIS and toilets! [x-posted to uk.railway] Most recent "more or less for cash" order on the Tube is EUR149m with Alstom for the 85 new cars on the Jubilee, so about GBP1.4m per car at current rates (no idea what proportion of components are built in Europe vs UK vs US$-linked-developing-countries, so actually GBP1-1.4m depending on the ratio). I thought we were running closer to GBP2m for mainline stock - one of the railway magazines (I'd guess may have been Roger Ford, since it's the kind of thing he'd do) had an interesting table a couple of years ago on the subject, IIRC showing HEx stock at the most expensive at around GBP3m per vehicle, but I can't find it online. TfL's North London Railway upgrade seems to be running at GBP1.4m per vehicle: http://www.tfl.gov.uk/corporate/medi...hive/3534.aspx -- John Band john at johnband dot org www.johnband.org |
Central line to be converted to AC?
On Apr 22, 8:09 pm, Clive wrote:
In message , Boltar writesWhy arn't they using it already, what are they waiting for? The A stock was doing 60 mph back in the 1960s with no ATO in sight. So was 62 stock on the Central line, but it was not authorised for use in tunnel sections. I'm not surprised. Could you imagine the piston effect that would have? People waiting on platforms would be blown down the tunnel :) B2003 |
Cost of new rail carriages (was Central line to be convertedto AC?)
On 23 Apr, 00:46, John B wrote:
On Apr 22, 9:57 pm, Steve wrote: Are Underground carriages really about GBP 1.5m-2m? I thought recent- ish DC electric surface stock (e.g. the 450s on SWT) came in at about GBP 1m per carriage, and for that you get motors, brakes and crashworthiness suitable for 100MPH running, aircon, PIS and toilets! [x-posted to uk.railway] Most recent "more or less for cash" order on the Tube is EUR149m with Alstom for the 85 new cars on the Jubilee, so about GBP1.4m per car at current rates (no idea what proportion of components are built in Europe vs UK vs US$-linked-developing-countries, so actually GBP1-1.4m depending on the ratio). I thought we were running closer to GBP2m for mainline stock - one of the railway magazines (I'd guess may have been Roger Ford, since it's the kind of thing he'd do) had an interesting table a couple of years ago on the subject, IIRC showing HEx stock at the most expensive at around GBP3m per vehicle, but I can't find it online. TfL's North London Railway upgrade seems to be running at GBP1.4m per vehicle:http://www.tfl.gov.uk/corporate/medi...hive/3534.aspx -- John Band john at johnband dot orgwww.johnband.org Some analysis from 2003, less the chart referred to in the text, at: http://www.alycidon.com/ALYCIDON%20R...004%202003.htm |
Central line to be converted to AC?
On 23 Apr, 09:02, Boltar wrote: On Apr 22, 8:09 pm, Clive wrote: In message , Boltar writes Why arn't they using it already, what are they waiting for? The A stock was doing 60 mph back in the 1960s with no ATO in sight. So was 62 stock on the Central line, but it was not authorised for use in tunnel sections. I'm not surprised. Could you imagine the piston effect that would have? People waiting on platforms would be blown down the tunnel :) How about we just ditch the trains and install massive fans to create public wind tunnel transportation - people could just jump in and out of the airflow. It'd be an exhilarating ride too, though those with a sensitive disposition about their hair (Mrs Prescott, Natasha Kaplinsky etc) will likely opt to stay in their Jags or taxi's on the surface. The tunnels might need a bit of a clean to remove all the dust first, and some padded lining to cover the tunnel walls might not be a bad idea either. The alternative would be to turn the tunnels into massive water flumes, so we'd have something akin to a water park under central London. Now that does sound like a good idea! |
Central line to be converted to AC?
On Wed, 23 Apr 2008, Mizter T wrote:
On 23 Apr, 09:02, Boltar wrote: On Apr 22, 8:09 pm, Clive wrote: In message , Boltar writes Why arn't they using it already, what are they waiting for? The A stock was doing 60 mph back in the 1960s with no ATO in sight. So was 62 stock on the Central line, but it was not authorised for use in tunnel sections. I'm not surprised. Could you imagine the piston effect that would have? People waiting on platforms would be blown down the tunnel :) How about we just ditch the trains and install massive fans to create public wind tunnel transportation - people could just jump in and out of the airflow. This has been semi-seriously proposed in relation to cycle lanes - since the main limit on bike speed is air drag, if you move the air at 10 mph in the direction of travel (involving putting the cycle lane in a tube), you give everyone a 10 mph speed boost. The alternative would be to turn the tunnels into massive water flumes, so we'd have something akin to a water park under central London. Now that does sound like a good idea! Ahem. http://groups.google.co.uk/group/uk....27e4f928db8b5a And that wasn't even the first time i suggested it, ISTR. tom -- YOU CANT TAKE AWAY HATGUYS HAT. THEN HE IS JUST GUY -- The_Toad |
Central line to be converted to AC?
On 23 Apr, 12:23, Tom Anderson wrote: On Wed, 23 Apr 2008, Mizter T wrote: On 23 Apr, 09:02, Boltar wrote: (snip) I'm not surprised. Could you imagine the piston effect that would have? People waiting on platforms would be blown down the tunnel :) How about we just ditch the trains and install massive fans to create public wind tunnel transportation - people could just jump in and out of the airflow. This has been semi-seriously proposed in relation to cycle lanes - since the main limit on bike speed is air drag, if you move the air at 10 mph in the direction of travel (involving putting the cycle lane in a tube), you give everyone a 10 mph speed boost. Ha, I haven't come across that idea before! It has to be said that when the air is moving at 10mph against the direction of travel, or indeed perpendicular to the direction of travel, cycling can be damn hard work. Still, it's all good for you - a friend used that very same philosophy when he came by a large number of knobbly off-road tyres and used them for his on-road cycle commute - "it's just going to make me harder"! Incidentally, whilst we're on the topic of cycle innovations, have you come across this: http://news.bbc.co.uk/newsbeat/hi/te...00/7340963.stm The alternative would be to turn the tunnels into massive water flumes, so we'd have something akin to a water park under central London. Now that does sound like a good idea! Ahem. http://groups.google.co.uk/group/uk....owse_thread/th... And that wasn't even the first time i suggested it, ISTR. Even as I was typing I was thinking 'this is a very Tom Anderson thing to say, I bet he's said it already'! Though your suggestion above is for canals - I was thinking more along the lines of passengers being issued with rubber rings and the water in the tunnel being propelled along to give a rapids-like effect, perhaps with a pool at each station so one could get out. Man it's a shame there aren't any water parks in London or the surrounds these days! |
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