Relationship between Capacity and Speed on Railways

Response to this request is long overdue. By law, under all circumstances, High Speed Two (HS2) Limited should have responded by now (details). You can complain by requesting an internal review.

Dear High Speed Two (HS2) Limited,

I am seeking clarification regarding two statements made by Sir David Higgins at recent Parliamentary Committees when being questioned about HS2.

Extracts are from uncorrected transcripts.

Transport Select Committee 17th November 2014
Q14
Sir David Higgins:
"It is a bit of a circular discussion because a railway line where trains travel at 220 miles an hour as opposed to 120 miles an hour clearly has nearly twice the capacity because you can have twice as many trains on it."

House of Lords Economic Affairs Committee 13th January 2015
Q251
Sir David Higgins:
"Capacity and speed are linked, because, where you have a train line and trains travel at 200 miles per hour, there are 18 per hour and each one has 1,000 people on it, if you run it at 100 miles per hour, you are going to get half the capacity on that train line."

These two statements, which say more or less the same thing, appear to be completely at odds with safe operation. As trains travel faster they take a longer time to stop as under constant deceleration the stopping time increases in direct proportion to speed and the distance required increases in direct proportion to the square of the speed. If the time between trains has to increase at higher speed then capacity must fall.

Please confirm whether HS2 Ltd has any documentation or analyis which supports the statements made by Sir David Higgins. If so, please provide full details.

Yours faithfully,

J Marriott

HS2Enquiries, High Speed Two (HS2) Limited

Thank you for your email to HS2 Ltd. Your email has been received by the
helpdesk. We aim to respond to all enquiries as soon as possible.

 

For more information please visit our website - [1]www.gov.uk/hs2

 

This email is scanned and cleared by Websense. HS2 Ltd is registered in
England and Wales. Registration Number 06791686, Registered office High
Speed Two (HS2) Ltd, One Canada Square, London, E14 5AB, England. This
email is sent subject to our disclaimer which can be accessed via our
website at [2]www.hs2.org.uk/email-policy

References

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Dear High Speed Two (HS2) Limited,

Capacity and Speed

By law I should have received a reply by 10th March 2015 but I have received nothing apart from an automated response. You have had more than sufficient time to respond to this simple question.

Yours faithfully,

J Marriott

Dear High Speed Two (HS2) Limited,

Please pass this on to the person who conducts Freedom of Information reviews.

I am writing to request an internal review of High Speed Two (HS2) Limited's handling of my FOI request 'Relationship between Capacity and Speed on Railways'.

I originally made this request on 11th February 2015, well over three months ago. I have not had any response other than an acknowledgement. You are required to respond as soon as possible and in any case in not more than 20 working days. The delay in responding is totally unacceptable.

A full history of my FOI request and all correspondence is available on the Internet at this address: https://www.whatdotheyknow.com/request/r...

Yours faithfully,

J Marriott

HS2Enquiries, High Speed Two (HS2) Limited

Thank you for your email to HS2 Ltd. Your email has been received by the
helpdesk. We aim to respond to all enquiries as soon as possible.

 

For more information please visit our website - [1]www.gov.uk/hs2

 

This email is scanned and cleared by Websense. HS2 Ltd is registered in
England and Wales. Registration Number 06791686, Registered office High
Speed Two (HS2) Ltd, One Canada Square, London, E14 5AB, England. This
email is sent subject to our disclaimer which can be accessed via our
website at [2]www.hs2.org.uk/email-policy

References

Visible links
1. http://www.gov.uk/hs2
2. http://www.hs2.org.uk/email-policy

L Fawcett left an annotation ()

This may help you to answer your own questions.https://a.gfx.ms//xlsx_57.png
Even if it doesn't, you may be better equipped to understand any response that HS2 dare to offer.

J Marriott left an annotation ()

The link provided by L Fawcett appears to be incorrect as it only points to a small graphic.

L Fawcett left an annotation ()

I'm told that the xls file I posted is wrong anyway but I'm promised an update which I'll post and hope it opens on this site.

Dear High Speed Two (HS2) Limited,

I requested an internal review a month ago and I have heard nothing either in response to my original query or in relation to the review.

Could you please let me know when you will respond?

Yours faithfully,

J Marriott

HS2Enquiries, High Speed Two (HS2) Limited

Thank you for your email to HS2 Ltd. Your email has been received by the
helpdesk. We aim to respond to all enquiries as soon as possible.

 

For more information please visit our website - [1]www.gov.uk/hs2

 

This email is scanned and cleared by Websense. HS2 Ltd is registered in
England and Wales. Registration Number 06791686, Registered office High
Speed Two (HS2) Ltd, One Canada Square, London, E14 5AB, England. This
email is sent subject to our disclaimer which can be accessed via our
website at [2]www.hs2.org.uk/email-policy

References

Visible links
1. http://www.gov.uk/hs2
2. http://www.hs2.org.uk/email-policy

Dear High Speed Two (HS2) Limited,

You have totally failed to properly acknowldge my original request made in February, subsequent chase ups and a request for an internal review made in May.

I understand that there were personnel problems earlier in the year which meant FOI/EIR responses were delayed. Your treatment of this request goes much further than that as I have not had the courtesy of a human reply.

All I am seeking is a link to documentation or a statement from HS2 that supports or disagrees with David Higgins' statements that capacity increases with speed. If it supports his view then the response should contain sufficient information to explain why capacity increases with speed.

Yours faithfully,

J Marriott

Joe Rukin left an annotation ()

John, you'd be quite within your rights to go to the ICO now, well actually a while ago.

Email casework@ico.org.uk. They can sometimes take a while to get back, but nothing like this long!!

HS2Enquiries, High Speed Two (HS2) Limited

2 Attachments

Dear Mr Marriott,

 

Thank you for following up on your email request. I am looking in to your
request and will respond as quickly as possible.

Please accept my apologies that you did not receive a response previously.

 

Kind regards,

Jane Ivey

 

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Jane Ivey | Freedom of Information Manager | HS2 Ltd 

Tel: 020 7944 4908 | [1][email address] | [2]Facebook | [3]Twitter
| [4]LinkedIn

High Speed Two (HS2) Limited, One Canada Square, London E14 5AB  |
[5]www.gov.uk/hs2

 

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HS2Enquiries, High Speed Two (HS2) Limited

3 Attachments

Dear Mr Marriott,

 

Thank you for your request to HS2 Ltd. We have treated your request under
the Environmental Information Regulations 2004 and I attach our response.

 

Kind regards,

Jane Ivey

 

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Jane Ivey | Freedom of Information Manager | HS2 Ltd 

Tel: 020 7944 4908 | [1][email address] | [2]Facebook | [3]Twitter
| [4]LinkedIn

High Speed Two (HS2) Limited, One Canada Square, London E14 5AB  |
[5]www.gov.uk/hs2

 

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Dear HS2Enquiries,
FOI15-1459 Relationship between Capacity and Speed

Thank you for your very belated (11 months) response to my request regarding David Higgins' responses to Parliamentary Committees in which he claimed that capacity increased with speed.

In your response you stated "David Higgins was providing evidence to the committees discussing the broader strategic context for high speed rail. It might be helpful if I add that David Higgins was not asked to provide a detailed plan for the operation of HS2, this discussion related to the broader concept of how speed relates to capacity."

In his statements to the the Committees it is clear that David Higgins presented a concept of how speed relates to capacity in a way that was likely to completely mislead the committees as to the true relationship between speed and capacity on a real railway.

It is clear from your response that the briefing note given to David Higgins for the Transport Select Committee was disingenious in that it totally ignores the scientific fact that trains travelling on the same track at twice the speed will require at least four times the distance to stop. They will therefore need to be spaced four times further apart in distance and twice as far apart in terms of time. Consequently, the capacity of a single track will halve, not double, if trains run at twice the speed.

Can you confirm that the briefing note does not correctly explain the relationship between capacity and speed on a real railway when considering the passenger throughput of a single track?

Can you provide the name of the person who wrote the briefing note?
Did anyone in HS2 Ltd authorise the issue of this note to David Higgins? If so, who was the most senior person who authorised its production and release?

Was a separate briefing note regarding speed and capacity prepared for David Higgins' appearance in front of the House of Lords Economic Affairs Committee on 13th January 2015? If so, can you provide that note and supply details of its author and any people who authorised its production and release?

Yours sincerely,

J Marriott

HS2Enquiries, High Speed Two (HS2) Limited

2 Attachments

Dear Mr Marriott,

 

Thank you for your email to HS2 Ltd.  We are considering your request
under the Freedom of Information Act 2000 and aim to reply as soon as
possible and no later than 17 February 2016.

 

Your reference number for the request is FOI16-1472.

 

Kind regards,

Jane Ivey

 

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Jane Ivey | Freedom of Information Manager | HS2 Ltd 

Tel: 020 7944 4908 | [1][email address] | [2]Facebook | [3]Twitter
| [4]LinkedIn

High Speed Two (HS2) Limited, One Canada Square, London E14 5AB  |
[5]www.gov.uk/hs2

 

 

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HS2Enquiries, High Speed Two (HS2) Limited

3 Attachments

Dear Mr Marriott,

 

Thank you for your email to HS2 Ltd. We have treated your request under
the Freedom of Information Act 2000 and I attach our response.

 

Kind regards,

Jane Ivey

 

 

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

Jane Ivey | Freedom of Information Manager | HS2 Ltd 

Tel: 020 7944 4908 | [1][email address] | [2]Facebook | [3]Twitter
| [4]LinkedIn

High Speed Two (HS2) Limited, One Canada Square, London E14 5AB  |
[5]www.gov.uk/hs2

 

 

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Dear HS2Enquiries,

Thank you for your response dated 19 February 2016 in relation to my original request dated 11 Feb 2015, just over a year ago.

My original question asked you to confirm whether HS2 had any documentation or analysis which backed up two statements made by David Higgins to Parliamentary committees that capacity increased with speed. Although the words used by David Higgins are not as clear as they could be, it is quite evident from the context of both statements that David Higgins was talking about the capacity of a single railway line in terms of trains per hour and his claim that the number of trains that it could carry would approximately double if they travelled at twice the speed.

In my request dated 14th December 2015 I asked for you to supply any statements or documentation that HS2 Ltd have that supports or disagrees with David Higgins' statements that capacity increases with speed.

In your response dated 11th January 2016 you said that the information was contained in a briefing note provided for David Higgins prior to the Transport Select Committee which claimed that "a 200mph train moves double the number of passengers a day than a 100mph train does." This is presumably based on the rather optimistic assumption that the faster train will make twice as many journeys in the same time.

However, the capability of a single train to carry more passengers in a day has nothing at all to do with the capacity of a single line to carry trains. Furthermore, in your answer to Q1, you state that the briefing note relates to the broader strategic context for high speed rail rather than a detailed plan for the operation of HS2. The briefing note is not therefore relevant to my questions or to David Higgins' statements. My original question therefore remains unanswered.

It is impossible to conceive that HS2 has not looked in some detail at the relationship between speed and the capacity of its proposed tracks to carry trains. Please provide relevant reports or documentation to show that HS2 Ltd understand the relationship between the speed of trains and the operational capacity of a single line, having regard to all the various features and characterisics along that line which could affect its capacity.

Yours sincerely,

J Marriott

HS2Enquiries, High Speed Two (HS2) Limited

2 Attachments

Dear Mr Marriott,

 

Thank you for your email to HS2 Ltd.  We are considering your request
under the Environmental Information Regulations 2004 and aim to reply no
later than 18 March.

 

Your reference number for the request is FOI16-1487.

 

Kind regards,

Jane Ivey

 

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

Jane Ivey | Freedom of Information Manager | HS2 Ltd 

Tel: 020 7944 4908 | [1][email address] | [2]Facebook | [3]Twitter
| [4]LinkedIn

High Speed Two (HS2) Limited, One Canada Square, London E14 5AB  |
[5]www.gov.uk/hs2

 

 

show quoted sections

HS2Enquiries, High Speed Two (HS2) Limited

3 Attachments

Dear Mr Marriott,

 

Thank you for your email to HS2 Ltd. Your request for information has been
treated under the Environmental Information Regulations 2004 and I attach
our response.

 

Kind regards,

Jane Ivey

 

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

Jane Ivey | Freedom of Information Manager | HS2 Ltd 

Tel: 020 7944 4908 | [1][email address] | [2]Facebook | [3]Twitter
| [4]LinkedIn

High Speed Two (HS2) Limited, One Canada Square, London E14 5AB  |
[5]www.gov.uk/hs2

 

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Dear HS2Enquiries,

I refer to your reply dated 18th March 2016 FOI16-1487 in response to my request dated 19th February 2016 and other requests going back to 11th February 2015. You have provided links to various documents but I contend that none of these provides any information to support David Higgins' statements:-

" It is a bit of a circular discussion because a railway line where trains travel at 220 miles an hour as opposed to 120 miles an hour clearly has nearly twice the capacity because you can have twice as many trains on it."
(Transport Select Committee 17th November 2014 Q14)
and
"Capacity and speed are linked, because, where you have a train line and trains travel at 200 miles per hour, there are 18 per hour and each one has 1,000 people on it, if you run it at 100 miles per hour, you are going to get half the capacity on that train line."
(House of Lords Economic Affairs Committee, 13th January 2015 Q251)

The documents confirm that the braking distance is critical to determining the headway between trains and therefore the maximum number of trains per hour. This is perhaps most clearly stated on p4 of the Bombardier document where it states that "the braking distance is the dominant contributor to interval [sic] between trains." Fig.2 shows just how dominant braking distance is at 360kph. Fig.3 clearly shows headway increasing with speed at speeds over 160kph.

On the basis of your replies, and the documents so far provided, you have been unable to justify either of David Higgins' statements. The documents show that capacity does not increase as speed increases, it decreases. I therefore suggest that David Higgins should write to the Transport Select Committee and to the Economic Affairs Committee explaining the true position and that HS2 Ltd or David Higgins should publicly apologise for making such misleading statements to Parliamentary Committees.

Of course if you can provide me with documents that do support David Higgins' statements then there would be no need to take the action I have suggested in the previous paragraph.

Yours sincerely,

J Marriott

Dear High Speed Two (HS2) Limited,

Please pass this on to the person who conducts Freedom of Information reviews.

I am writing to request an internal review of High Speed Two (HS2) Limited's handling of my FOI / EIR request 'Relationship between Capacity and Speed on Railways'.

Please note my original request was made in February 2015 and it took until 11th January 2016 to get an initial response, which did not provide the information I sought.

I have not received an acknowledgement or response to my last request for information which I submitted over 4 months ago on 2nd May. I asked that if you could not supply information to support David Higgins' statements to parliamentary committees that 'capacity increased with speed' that he should apologise to those committees for misleading them. Can you confirm whether such an apology has been made and if so provide details of what was said and when it was sent?

A full history of my FOI request and all correspondence is available on the Internet at this address: https://www.whatdotheyknow.com/request/r...

Yours faithfully,
J Marriott

Dear High Speed Two (HS2) Limited,

Please pass this on to the person who conducts Freedom of Information reviews.

I requested an internal review in September 2016 regarding the handling of my FOI request 'Relationship between Capacity and Speed on Railways' which concerned the claims made by David Higgins that capacity increased with speed. I have had no response. I pointed out that nothing you have supplied so far supports his claim.

A full history of my FOI request and all correspondence is available on the Internet at this address: https://www.whatdotheyknow.com/request/r...

Yours faithfully,

J Marriott

HS2Enquiries, High Speed Two (HS2) Limited

Thank you for your email which has been forwarded to FOI.

Kind regards

Simone Wright | Helpdesk | HS2 Ltd
Tel: 020 7944 4908 | [email address] | Facebook | Twitter | LinkedIn
High Speed Two (HS2) Limited, 2 Snowhill, Queensway, Birmingham, B4 6GA | www.gov.uk/hs2

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