Vehicle Design is an Inside Job ft. New Tube for London

Aeronautical designers have a saying, ‘Pretty works’. That is to say, an elegant and aerodynamic aircraft generally has excellent handling characteristics and good speed (the Spitfire and Concorde come to mind). London Transport’s Lord Ashfield and Frank Pick knew the value of striking, clear design – from station architecture to commissioning Edward Johnston’s typeface to cut through advertising’s visual bombardment to provide clear indication to passengers.

London Transport’s long design history

User experience (UX) is a buzz phrase nowadays, but has been practiced for over a century. London Transport was one of the pioneers, looking at how to make it clearer and simpler for passengers to identify and use its services. Starting with crisp graphics like the roundels for different modes, to cut through the clutter of shouting adverts. To the design of the Underground and bus stations themselves, even bus garages, with style and elegance, yet designed for optimised passenger flow and maximum throughput.

So it is with building, train, and bus design – indeed, the public’s perceptions are the slipstream of acceptability. Styling was considered just as important as functionality, as Frank Pick believed in ‘fitness for purpose’ and the power of good design. From architecturally significant stations using sleek yet robust materials, to streamlined modern vehicles, London Transport became known for its memorable user experience.

Designs need flexibility and adaptability to be useful in the decades to come. Comfort and usability have also come to the fore, with the recent ironing board seat fiasco. The Department for Transport (DfT) had specified a technical requirement for carriage seating on the most recent fleet of Thameslink trains, but had not specified comfort. So the bidders met the technical specification, but failed the customer. User comfort is needed, not rigid specifications.

These days, TfL still continues this design imperative, and draws upon leading designers and architects, as we investigated in 2015. At the start of the pandemic, I partook in a Rail Virtual Conference session on 25 June 2020. In particular, the Notes from The Future of Innovation and Digitisation in the Rail Industry presentation, where one of the presenters was Paul Priestman. He is head of PriestmanGoode, a design studio that specialises in transport design.

PriestmanGoode aims to continue the tradition of great British design. Their philosophy is that designs should be simple, elegant, intuitive, easy to maintain, and efficient to manufacture. From aircraft interiors, airports, public transport and high speed trains to hotels and consumer products, their diverse portfolio enables them to draw from their experience across different sectors.

London Underground and predecessors have had a long history of design excellence, even to bus garages. We at LR Towers have a great respect for design, having covered the modernised incarnation of Johnston’s Underground typeface, and having linked to many articles from The Beauty of Transport and Transport Designed, amongst others.

Indeed, philatelists will tell you that a number of London Transport designs have been featured on Royal Mail stamps as great examples of British design.

Nevertheless, an elegant design is often much work to achieve, requiring analysis in many dimensions – engineering, use, looks, manufacturability, assembly, and maintenance. It is an art to achieve a good balance of all these factors.

Pitfalls of the New Routemaster

This was promised to be a new transport design classic – a sleek redesign of the Routemaster. But it was not designed by PriestmanGoode, but by then-Mayor Boris Johnson’s favoured stylist, Thomas Heatherwick. The New Routemaster is a bold modernisation, but it sorely disappoints on execution.

The lack of opening windows, interior panels resembling cheap 1970s rough plastic, and under-powered air cooling were technical specification problems, not visual design issues. Although it is unfair to pin the blame solely on Heatherwick,TfL had rejected opening upper-deck windows in Heatherwick’s design. It took six years for TfL to agree to have them retrofitted.

The open rear platform was a nod to the original Routemaster, but with Oyster cards instead of Inspector Blakey’s charges, unpaid journeys were easy and common. Again, a specification problem.

Despite the striking design of the New Routemaster, the built bus’ poor materials, air cooling, and ventilation have soured Londoners on the bus. The public generally associates TfL or then-Mayor Boris Johnson for the New Routemaster’s shortcomings, but public transport (and design) nerds often pin the blame on Heatherwick. Such are the pitfalls of a designer – once out of their hands, a design can mutate in unpredictable ways, by the downstream manufacturing, testing, and operations processes. Ultimately it is the commissioning agency, and their political overlord(s), that set the production requirements.

New Tube for London

In 2014, faced with ever increasing demand on key Tube lines, Transport for London (TfL) launched a competition to design the next generation deep level Tube trains called the New Tube for London (NTfL). The current 70s era stock is overdue for replacement. Three firms bid for the contract, but PriestmanGoode’s track record in aviation and transport design gave it a key advantage and it won the contract. We first looked at this initial Tube train design at that time.

The main design restriction was to ensure that the trains would require no modification of existing station platforms and tunnels, whilst future-proofing the design as much as possible. As this is a design article, not a technological one, we will not get into the aborted ‘fully automated train’ specification, nor the details of train signaling upgrades, which we looked at in SSR Signalling Upgrade Again and NTfL.

TfL worked with PriestmanGoode on the new Tube train design. The design brief was to create a tube train that is beautiful, simple, functional and maintainable, whilst instilling the iconic London Underground design aesthetic. This will be done using hand hold (grippage) styling and colours, including the familiar ox-blood red. However, the design also had to not only increase train capacity, but to also improve the speed and frequency of trains, whilst retaining the visual cues of London Underground transportation. The new trains will be a standard design, which will be modified as necessary for individual lines. First appearing on the Piccadilly line, they will also equip the Bakerloo, Central, and Waterloo & City Lines, albeit with modifications to suit each line. Ultimately, a total fleet of 250 new trains is envisioned.

The design envisioned a number of technological and usability upgrades:

• Walk through carriages, like on S stock and Overground trains, to use the full length of the train for passenger carrying, and to encourage passengers to spread out to maximise capacity and minimise dwell times.
• Reduce the length of the carriages and increase their number to allow articulation which would reduce the number of bogies per train, thereby saving weight, complexity, and maintenance. A side benefit of reducing the number of bogies is that it creates additional space underneath to house the cooling equipment. Previous Tube trains never had the space for much equipment underneath the carriage (nor overhead because of the narrow 3.6m diameter tunnels). There will be 9-car trains replacing existing 6-car trains [Corrected]
• Wider double doors (and no single doors) equally spaced along the length of train, along with seamless wheelchair access to allow passengers on and off faster. This is necessary to maintain existing dwell times despite some of the so-equipped lines anticipated to carry up to 60% more passengers.
• The entire train fitted with recessed LED lighting for much less maintenance and much lower heat generation.
• Digital screens rather than paper billboards to provide live updates, and for significantly less labour to update maps and adverts.
• Air-conditioning or air cooling built-in.
• Wi-Fi to allow the train to communicate with the depot to provide status info and live disruption messages. [Corrected]
• Floor-to-ceiling poles angled away from passengers to provide more headspace.
• Thinner walls made possible by using aeroplane materials, such as aluminium, to create more internal space.
• A comprehensive effort to reduce the heat generated inside the carriages, through energy efficiency and light weight materials, plus state of the art regenerative motors that convert train momentum into electrical energy fed back into the power grid. This greatly reduces electricity use and heat generated by friction brakes. [Corrected]
• Modular design as much as possible that allows components to be easily replaced if damaged or updated.
• Elimination of nooks or crannies where dangerous packages could be hidden, whilst facilitating station staff being able to check the entire train quickly.

With the walk-through carriages and larger vestibules, there will be more standing room, increasing train capacity.

Hold on a sec – a 60% increase in passengers?

This struck us at LR Towers as quite improbable – there’s no way that the aforementioned list of interior design changes could result in such a large increase, short of pulling all the seats out, or having them all fold up. The first clue was the last line of this bullet point “This is necessary to maintain existing dwell times despite some of the so-equipped lines anticipated to carry up to 60% more passengers”.

The NTfL interiors will not be noticeably different from line to line, other than possible selective door opening, or SDO as it’s known in the trade. So let’s break down this 60% total line capacity increase. It splits three ways:

1. More capacity per train, a 10% increase.
2. More trains on the Piccadilly Line (there were never sufficient trains after the Heathrow extensions opened in the first place), which comprises 10-15% on the increase, depending on final desired Heathrow T4/T5 service levels and stopping patterns, plus potential District Line alterations.
3. Greater frequency due to signalling upgrades, a 35-40% increase.
4. Combined with the signalling upgrade, unlock the improved performance of the trains to reduce journey times. For every 2 minutes saved, it effectively is the equivalent of another train. [Added]

Now looking at the 10% on-train capacity increase in more detail:

• The New Tube for London trains are 5.1% longer than existing trains, with 7.1% more floor space (this is only for the Piccadilly line. Central and Bakerloo line trains will be more or less the same length as current stock). Which has nothing to do with PriestmanGoode.
• The new trains are walk through, with the equipment normally fitted in the vehicle ends going under the floor or the middle set of some seats.
• Having more, shorter cars cars than LU originally expected has led to an increase in seating, which in turn led to less of an increase in standing capacity, as the space under some of the seat block is needed for equipment. NTfL will have 40 more seats and from 17 to 25 additional standees (depending on wheelchair space assumptions), at 5 passengers per square metre.
• The LU train capacities are based on standing densities of 5-7 passengers per square metre, hence a small tweak can make a big difference and change the total numbers. In particular, LU plans for 5 passengers/sq m, but designs the structure and braking for 7 passengers/sq m. [Updated]
• Passenger doors per side have gone from twelve double doors (1.37m wide) and ten single doors  (0.685m wide) on existing stock to 18 wider double doors on the new stock (1.69m, which is 23% wider). So in total, the present 23.29m of door width per train will increase to 30.42m on the NTfL. However, the vestibule width on the new trains will be the same as the door width, unlike the old trains, to discourage too many passengers to attempt to board.

The different entities (LU, Siemens) assume different train passenger densities. This goes back a generation at least, as the previous Tube stock design iteration saw the Private Finance Initiative (PFI) contractors reportedly create a new crush loading metric of 8 passengers per square metre, to make the total capacity sound much more impressive.

Latest New Tube for London design iteration

In November 2018, TfL had awarded Siemens the contract to supply 94 nine-car Inspiro London trains for the Piccadilly line, to start operation in 2025. There are options for LU to order additional trains for the Bakerloo, Central, and Waterloo & City lines subsequently. Interestingly, Rail Engineer reported a preview on the design launch of the Siemens Inspiro train for the Piccadilly Line, so we can see what changed on the surface.

Whilst the technological aspects are not design related, the Inspiro trains will provide cost savings through increased reliability, greater standardisation of train operations, equipment, spares, and maintenance. These benefits will multiply if the trains are ordered for the other three lines as well.

In addition, the trains will be significantly more technologically advanced, and more energy-efficient than current stock. Part of this are the low-loss permanent magnet auxiliary power converters made with silicon carbide technology, which has lower losses than the current silicon versions, as well as lithium ion batteries [Updated]. With the LED lighting and advanced energy management, energy consumption is reduced by 20 per cent compared with the existing fleet. Another energy efficiency introduced in these trains is coasting, which is computer controlled in conjunction with the train’s signalling. If the train is on schedule, traction power is disengaged sooner and it coasts for longer distances before braking is applied. If not, the train is powered more and coasts less to reach the platform sooner. On the Piccadilly line, this will be enabled once the signalling is upgraded [Added]. All of these advancements results in less heat radiated into the tunnels and platforms.

IanVisits further compares the 2018 initial Siemens design vs their recently announced 2021 NTfL design. Nevertheless, we await further under-the-bonnet information on Siemens’ latest NTfL design.

The Studio’s other rail designs

“Train travel is often regarded as the poor relation to air travel. There’s been a lot less investment in train design.”

Paul Priestman quoted in MediaRail online magazine

Priestman singled out some factors that make train travel more pleasant: a smooth, quiet journey, productive use of time, and most of all, space. Not being tightly packed like on airliners is a major blessing.

Having designed business class cabins for Swiss International Air Lines, Virgin Australia Qatar Airways, Aegean Airlines, and United Airlines amongst others, PriestmanGoode is well positioned to bring some aviation design concepts and pizzazz to rail interiors.

Priestman’s studio has recently contributed to the design of Austrian state railway ÖBB’s future Railjet and Nightjet trains. In particular, an innovative sleeping pod design for the Nightjet sleeper trains, which provide social distancing and privacy with space efficiency.

Other small details can make a big difference – a ramp is incorporated into the steps to board and alight the train, so that luggage can be easily wheeled on board.

Good bones

Like an aircraft family, good bones are necessary for adaptability and evolution of a design. Paul Priestman himself comes from a family of designers – his mother Jane Priestman OBE was a self-taught designer who headed British Rail’s Design group in the 1970s and 1980s. She worked for over 40 years in design management and the co-ordination of major national and international projects, particularly in transport. During that time, the concept of overall design was not fully understood or appreciated.

At the British Airports Authority (BAA), she worked with all seven major UK airports on their identity and retail branding. She was then appointed British Rail’s Director of Architecture, Design and Environment in 1986, in a new post created just for her. In her 5 years there she managed nearly 300 architects, graphic designers, and an environment group to revamp train interiors and maps. She also commissioned Nicholas Grimshaw to design Waterloo International Terminal for Eurostar trains.

In 1985, Jane Priestman was made an official honorary member of the Royal Institute of British Architects (RIBA), and in 1991 appointed an OBE for her contribution to design and staunch support of design management. At the age of 85, she was also awarded the Ada Louise Huxtable Prize lifetime achievement award in 2015. Paul Priestman’s father and brother are also in design fields, both being architects.

Not his first rodeo

Paul Priestman sees high speed trains as vital for the future of Britain, as the low-carbon, sustainable transport of the future. Currently splitting his time as Global Creative Director of CRRC Sifang since 2013, Priestman is also working on high speed train designs in China and the rest of the world. He believes that whilst the economic and political benefits of a world-class high speed rail network are clearly understood, having a train to be proud of is equally important. Style is a key factor in persuading people to leave their cars at home, eschew air travel and make rail their first choice where possible.

A new way of sitting

The year 2016 was a summer of discontent on UK railways, with many London commuter trains filled to 200 per cent capacity, according to Department of Transport data. This spurred the Rail Safety and Standards Board (RSSB) to launch a design competition to address overcrowding. With many lines having platforms that cannot be easily extended, nor the size of trains increased, innovative solutions were required. As PriestmanGoode had done a lot of work on aircraft interiors and is experienced in addressing problems like seat design and passenger movement, the studio won the RSSB competition to further develop their concepts to seat more passengers on trains, that can be installed on new or existing trains, trams, and buses.

Two proposed new seating models

Despite Paul Priestman stating that space is a major consideration in train design, the brief for this competition was the opposite – how to fit more passengers in, without having them stand. He had noticed that “young kids, they don’t sit down – they lean, they prop, they lounge.” He also noted that traditional seating requires the legs jutting out in front, which takes up a lot of space. His agency also took inspiration from bar stools, which encourage a more active, upright posture, but are associated with leisure and relaxation.

Shrinking Horizons with increasing pitch

The Horizon concept features rows of twin seats that are closely pitched together, slightly offset laterally to increase shoulder space between passengers. These seats have been ergonomically designed to provide passengers full support so they can take the weight off their feet, with each seat having two footrests for passengers of different heights. A small foldaway table on the facing seatback with grooves that support devices at a range of viewing angles, with USB charging points as well. The studio estimates that this seating model could increase seating capacity by 20 to 30 per cent.

The above rendering does not look too bad. Essentially, passengers would get a different way of sitting that’s more like a semi-upright perch, like the leaning bumper cushions at the end of Tube cars. Priestman believes that this kind of seating could also be preferable for health reasons, as recent health research has highlighted the dangers of sitting for too long a period. However, fill these seats with actual passengers, and it will look like this:

Given the toast rack stacking of passengers, we do not believe that this will be a popular choice at all for commuter train operating companies. A polite way of saying this is plain bonkers. It is a good example of meeting a technical spec (cram in more passengers) whilst failing the customer – this will likely be as popular, and as big a slight on the rail industry, as the aforementioned Thameslink ironing board seats.

Island Bay seating bays

The Island Bay design below is designed to be a flexible solution. Four passengers sit facing each other around a small table:

The seats can fold up at peak times to create leaning space, as does the small table to become an additional seat at the end of each bay with a padded backrest There is also an extra leaning location at the end of each bay:

Priestman estimates that this design would create 15-20 per cent more seats, plus increased standing capacity. The layout can also accommodate a wheelchair. However in the pandemic world, less rather than more sociable layouts are preferable.

The above image does appear to be more like a crowded pub setting than a train interior. Which is great if traveling with a group of friends, or family that are really chatty. But I suspect that most British passengers would not like such close proximity to strangers, without alcohol to soothe the nerves and grease the conversation. It would be tolerated for shortish commuter trips, but would be wearying on repeated experience. Most of all, whilst younger generations might be fine with such close, informal settings, parents with children and older generations will much prefer traditional seating. On inter-city trains, such a crowded layout would lead to bitter complaint. UK rail passengers already deal with engineering works causing such overcrowding on current trains – have to put up with such crowding on a daily basis might well be a line too far.

Island Bay Covid variation

Whilst PriestmanGoode designed the Island Bay seat layout in 2016, the studio adapted it in 2020 for the Covid Age to expand on-board bike storage. One side of the bay seating would be folded up for social distancing, and with the addition of tyre holders, the space can now be used to store passengers’ bicycles.

Uh… no.

To date there has been little interest from passengers, especially older ones. The thought of being even more cramped, and being perched up higher, does not excite. To date, no British train operating company has taken up either of these PriestmanGoode designs.

Concept designs are public thought experiments

Not all concept designs are successful. And like science, sometimes there is more to be learnt from failure than from success. Albert Einstein used thought experiments to develop some of his most famous derivations, so there is a lot of value in the method.

Concept designs are more about what is possible, than a prediction of what designs will look like 5-10 years hence. Like architecture practices publishing their visions of future stations. They’re not seriously proposing building them, just demonstrating what new building technologies could be capable of producing. Or like fashion designers, who create outlandish designs that in themselves rarely filter down to regular people wear, but provide a vision of what is possible and where the trends are heading. The concepts are meant to be critiqued and discussed, as this process generates more ideas. For train, and station, concepts, they are also an opportunity to include new technologies and project potential uses, which are evaluated publicly. Engineers then pick out the best ideas, reject the impractical ones, and distill them into a workable product years later.

So what does is it take to make a design a classic? Putting the user first – in ease of use, comfort, reliability, and style.

Many thanks to fellow transport design commentator Daniel Wright of The Beauty of Transport, ngh, and Snowy, for their assistance.