Rail projects : When BL met BR – The APT

Many people are unaware that some British Leyland products ran on the rails as well as the roads. AROnline looks at the Advanced Passenger Train (APT-E), which was BL’s first engineering partnership with British Rail.

Story: Mike Humble

St Pancras 1974 - APT-E by British Rail - Engines by British Leyland

I make no apologies for the fact that I love trains, and if it hadn’t been for the fact that in 1988 when I discovered my slight colour blindness during a BR medical, my career path would have certainly been much different. Growing up in Darlington (the original railway town) many friends’ parents had either worked or had some involvement on the railway in one capacity or another. My late Grandfather served 47 years on what was the LNER and British Railways so I kind of reckon it’s in my blood, be it the smoke and smut of a Gresley Class A4 loco or the screaming cry of the HST on notch 5 – my passion for trains has never died.

By taking the words ‘Coal’, ‘Steel’, ‘Rail’, ‘Leyland’ and adding ‘British’ to the title, you end up with four very different industries with one common thread running through them – turmoil. It all makes fascinating reading for those under a certain age, but I am old enough to remember each and every one of them slowly fade away into memory – trust me, if you were around at the time, it wasn’t pleasant to witness and the closure of MG Rover in 2005. For me, felt like the final nail in our industry’s coffin. For all the wrongs and rights of BR and BL, they employed some truly talented engineers and old school-designers blessed with skill and handed down disciplines now sadly lost along with the companies who employed them.

A high-speed future

Following the Beeching Report of the 1960s (an in depth analysis of the state of BR), several ideas were put forward for re-shaping and modernising the railway. At the time, it was still struggling with shrinking passenger numbers, spiralling losses and an antiquated infrastructure, which dated back to Victorian times. Today, we see the argument for a new high speed rail line from London to the Midlands making regular news articles, but this idea had been put forward in mid-’60s. This was originally discarded owing excessive cost, so any reduction in journey times from A-to-B had to be found by means of faster trains rather than a bespoke high speed line.

Some work had been done with Electrification for part of the London-Glasgow line. Electric trains running at 25,000 volts (25KV) were superior in power and acceleration than the previous steam- or diesel-fuelled locos, but the infrastructure of overhead masts, cabling and line side transformers was massively expensive – so alternative power became scrutinised. In the early 1970s, the most powerful loco on the BR network was the Class 55 (Deltic) with an available 3300bhp. These ran exclusively on the East Coast Kings Cross-Edinburgh line at a maximum speed of 100mph. But BR wanted a higher top speed and the braking system of these trains could not cope with any more increased demand.

In order to provide a high top speed, yet still operate within the existing signalling system, it became obvious that everything needed to be overhauled – from suspension designs through to braking systems. The biggest problem regarding speed BR faced, was the curvature of the track, so the idea was put forward for a tilting train that could lean into the corner while still maintaining a high speed – a brilliant concept.

Some of the best boffins were hand-picked to head up two small teams to design and built a gas turbine prototype tilting train. It needed to be able to operate on Inter-City lines, where electrification was not present. The other team were to design and produce a diesel-powered loco capable of equally impressive great speed and these projects became known as the Project APT-E – Advanced Passenger Train Experimental; and the HST – High Speed Train.

In partnership with British Leyland

On either side of the picture - The tiny Leyland 350 gas turbine power units of the APT-E

During the 1960s and ’70s, Leyland Trucks had produced a working Gas Turbine engine that was incredibly small and light in relation to a very high power output. The British Railway Board approached BL with a view to working in partnership, and developing, this world-leading project, and work started quickly. The design brief was for a non-electric, self-tilting high speed train, that was to be produced in a state of the art design and research centre in Derby. The experimental train had two power cars, each equipped with four Leyland 350-series Gas Turbine engines, rated at 300bhp per unit for propulsion. These ran the alternator sets that fed electrical current to the axle mounted traction motors.

The engines were soon uprated to 350bhp per unit, after modification to the heat exchangers. The units were, in practice, jet engines which ran at extreme temperature. Other novel features included a hydrostatic braking system, which in effect was a water turbine that forced liquid through what appeared to be a torque converter in reverse. The theory behind this was that reduced friction and heat meant less wearing parts. And the secondary braking system, via discs and pads, came into effect at much lower speeds than normal.

The end result meant the train could run at higher speeds, yet still stop within the required distances of the traditional colour signals. And also, drastically reduce maintainance costs.

The train ran in a fixed formation with the bogies (axles) being articulated and shared between the coaches, while also being air-suspended and featuring a fully automatic passive hydraulic tilting system. Upon entering a curve at speed, sensors would pick up the G-forces of inertia and jack up the suspension making the train lean into the corner – just like a motorcycle would do. This would counteract the forces and provide a 20% higher cornering speed than a traditional train carriage.

Testing times

After some initial Union bickering over single driver operation, the APT-E set to work proving itself. And the previously unknown technology was showcased in the media with a blaze of publicity. Schoolboys once again would marvel at the sleek shape – which looked like no other loco before.

The Class 43 / HST won the battle for high speed supremecy and still earning its keep since 1976

The tapered style of the train body not only looked futuristic. But it also served the critical function of making sure that when exiting tunnels, bridges or the passing of an oncoming train running on the opposite line when in tilt mode, did not come into contact with each other. The cost of altering the thousands of aforementioned structures was not possible, so the new train had to run within the existing British Rail track and infrastructure.

Any means or gain in speed or reduction in journey times could only be acheived by attention to detail of the locomotive or train design as a whole. A 14 mile section of closed track on the former Midland Railway near Dalby was upgraded & re-opened for private test and research purposes before the APT-E was fit for proving trails on the BR network. This line was ideal owing to the number of severe curves and bridge structures it contained. The Dalby test track later featured as the site of the famous Nuclear Flask train test crash in the 1980s.

Even though some impressive runs had seen the train operate over 150mph on the Western line close to Swindon, the APT-E proved to be temperamental and costly to run. British Leyland was in a serious cash dilemma, and quickly losing interest in Gas Turbine technology following the 1970s oil crisis. But also the rival prototype HST (125) was proving to be a superior project in the long run.

The diesel beats gas turbine

The HST today, still evokes a vision of speed and efficiency even after an incredible 36 years in service. The APT project was shelved, only to become a viable option again, in 1981 – after adopting an electric powertrain. Sadly, pushed into service before its time, the APT was finally dropped after some disgraceful coverage by the media and general BR apathy in 1986.

The Governement were also putting pressure on BR to deliver yet at the same time refusing to any fund the project any further.

At full degree tilt - The later electric APT-P was killed off, just as it was coming good!

Sadly, the APT never had the chance to prove itself partly thanks to Government meddling and the media making a great deal of noise. The constant sniping regarding some technical hiccups and the reported nonsense that was ’tilt syndrome’ – the so called sickness caused by the APT – made sure that once again, the great of the good was destroyed by the English tradition of mocking our own industry, rather than backing it. When will we ever learn!

For those wishing to view the amazing experimental APT-E, this is on public display at the impressive new National Railway Museum in Shildon near Darlington. The electric APT-P is on public display at the Crewe Heritage Railway Centre in Cheshire.

Mike Humble


  1. The story of the APT is indeed a tragic one, that the teething problems were on the verge of being cracked just before the Thatcher government pulled the plug. Hats off to BR for hedging their bets though by simulteneously developing the IC125/HST at the same time, which is still a world beating piece of engineering still giving sterling service to the nation. The tilting technology was sold to Fiat, who finally managed to get it to work properly and sold it back to us in the form of the Class 390 Pendolinos now used by Virgin Trains; just at the same time as our once proud rolling stock industry began to die a slow death. Great names like English Electric, Metropolitan-Vickers, Metro-Cammell and many others are all dead and gone.

  2. Another less celebrated BR-BL collaboration was of course the Pacer (Class 14x) series of diesel multiple unit (aka “Railbus”) – a bargain basement train for use on rural branch lines and minor commuter routes. The whole idea of plonking a Leyland National bus atop a modified freight wagon and hoping that the end result would be something brilliant could only have BL in its concoction somewhere. Anyone who has had the misfortune to ride in one of these “nodding donkeys” will know exactly what I mean!!!

  3. And the Italians, who BR sold the patents to. The Virgin Pendolino’s come VIA Fiat. They also had some serious bitter pills to swallow before they would operate right, oddly enough not reported by the media!

  4. Where did it go wrong? Money. Ultimately we never had the infrastructure for the APT to run on. If a HST did the same job for less money on perfectly servicable yet antiquated equipment, it was a no brainer. Subsequent BREL rolling stock had space for the retrofitting of this tilting equipment however.

    Make no mistake the train IS the way to travel (readers have rummage on http://www.seat61.co.uk for some excellent beano plans) but it isn’t cheap. Convience never is…

  5. Not forgetting all the additional surge equipment fitted to the OHL equipment because of transmission problems!

  6. Indeed Andrew!

    The HST will never be bettered, though sadly muted thanks to the PC numpties who insisted on fitting German MTU engines and throwing away that awesome sounding Valenta 12RP-200 engine & the Marston type cooling fans.

    Such a shame as the later Paxman VP-185 power unit BR played with was everything the Valenta was and more. Though what did make me sad was seeing the state of the Worst Late Western sets often as not running on one power unit with gallons of oil bleeding down the bodyshell of the crippled power car.

    GNER did a fantastic job of re-invigorating the magic of rail travel with a perception of high quality – once again, blown to bits thanks to National Express trying to run a prestiege rail contract like a bus company!

    With regards to later rolling stock, indeed the MCW built MK4 coach and Class 91 rolling stock of the ECML were of the same tapered design in the idea of maybe retro fitting tilt. But for me, its the MK3 & HST combo thats simply hard to beat.

    Interestingly, it was down to the Washwood Heath Plant of Bombardier (formerly Metro Cammell) to retro fit and carry out the design recalls that the Italians caused on the Pendolino – one last hurrah before they shut it all down!

  7. I remember reading a fantastic book about the APT (APT – A Promise Unfulfilled by Hugh Williams; well worth getting hold of a second-hand copy if you are interested in railways). It was written by a member of the test team on the original APT-E (experimental; the blue and grey one).

    Basically, they had the tilting technology pretty much sorted; it just needed final tweaking. Unfortunately British Rail introduced an APT-P (prototype) service with three prototype electric trainsets before the tilting system was completely sorted, thus gaining negative (and scornful) press. In addition, the electric power was provided by overhead lines, meaning that the train had to have one or two powercars (depending on train length) which were located in the middle of the train, due to the overhead cable pickup technology available at the time for the speeds that the APT was expected to achieve (the pantograph cleverly remained vertical no matter what angle the train below was at). This meant that the APT-P was basically two trains in one, with two sets of staff, two buffet cars, two sets of separate first and second class etc on either side of the driving cars in the middle, which only had public through access in an emergency. This duplication of staff and facilities made the APT-P very expensive to run.

    In addition, the HST125 (InterCity 125), which was designed after the APT-E and almost as an afterthought (it was intended to fill the gap between the end of the powerful Deltics and the new generation of electric trains for the main line InterCity duities) had proven to be a very capable trainset, with a design speed of 125mph (it could actually do almost 150mph) it was not that much slower than the 150mph APT-P but was obviously far more flexible and could run on existing tracks at high speed with no changes to the infrastructure. The fact that the HST125 is still in action three decades later, and shows no sign of being discontinued, shows how right the design was originally.

    Sadly, we British were the innovators with the tilting train yet we never got to be the manufacturers – things could have been so different if there had been more testing before releasing the product on an unsuspecting public. Where have we seen that before?

  8. This is the original prototype HST – it had the same colour scheme as the APT-E, grey with blue stripe. The cab area was yellow. Note the strange double front window and lack of quarter windows.

  9. @ Steve

    I was told that a simple modification to the axle box ratios would enable a HST to easily acheive 150. The standard sets were geared to compromise a workable crusing speed with decent acceleration.

    The HST in production form was really having the knackers ripped off at anything over 140mph and indeed BR Inspectors equipped with hand held ray guns (yes they did have them) would and could regularly catch drivers operating at speeds in excess of 135mph.

    Buffet car staff would tend to know the driver was “thrayping” the train beyond 130 as the bogies would start to hunt slightly, causing the bone china and cooking implements to jingle and clink with the vibrations.

    Also with ref to your uploaded picture – another feature of the protoype HST which did not carry over on the production set was the extra driving cab where the luggage / guard compartment was fitted. A result of the designers utilising the wrong way operation or freight duties, akin to the class 91.

  10. @ Mike Love the idea of the HST speed traps and drivers giving them some beans! The HST was well ahead of its time – I think it still holds the diesel speed record at 148mph.

  11. If I have this right, I think that the HST and APT projects were to run over ordinary railway lines, unlike the TGV and Shinkashen (which translates as ‘new main line’, not ‘bullet train’). It’s a shame the project never became a reality as it would mean us not spending billions on High Speed Two. Seriously, it may sound a good idea to politicians now, but I can also imagine Tony Benn thought it a good idea to merge BMC and Leyland. And look how that turned out!

    There were so many poor decisions made by government back then relating to industry and infrastructure. Sure, it seems that only the actions of a certain minister in ’68 brings us together, but this seems to be another example of a misjudgement that will leave us footing the future bill.

  12. Its still a formidable piece of engineering that continues to cut the mustard. Who would have thought that boarding a HST some 36 years after introduction could still make many a grown man feel subconciously exited about travelling at 125 miles an hour.

    When I lived in Bedford, I would often spend some time at Midland station where the line straightened out towards Wellingborough, just as the driver “tapped up” to notch five. I would savour the rising pitch of the screaming Napier turbocharger and take in lungs of the fumes of exhaust.

    The hairs on my neck are tingling just by re-calling this!

  13. @Mike Somehow that anecdote brings a bit of the old romance back to train travel. I too had a bit of a love affair with the rails, so much so that not even commuting on Britain’s second busiest railway line, including a run through what I think is the busiest stretch of railway in the UK, still feels fantastic, a novelty even. 125 mph doesn’t sound like much considering I have been aboard 200mph Eurostar trains before, but imagine how it must have felt back then.

  14. Fascinating read. I still enjoy traveling in 125s into Paddington, ever since my first time in I guess the late 1970s, but it would be even better if the APT had made it into service too…

  15. The MTU engined HST’s daily clear 125mph through our traps in the hot axle box detector in Maidenhead….

  16. The most powerful Locomotive on the BR network in the early 70s was the Class 87 AC Electric – 5000hp. More power than two HST power cars combined. As for the Pendolinos, these where very much an Anglo/French/Italian collaboration. The traction equipment all came from the former GEC works in Preston and the vehicles where assembled at Washwood Heath near Birmingham. Only the tilting bogies where Italian/Fiat. I’m not aware of any serious problems with these trains having ridden on them regularly from day one. Smelly toilets and eratic air conditioning are the only issues that spring to mind. Now they are one of the most reliable trains on the network racking up massive mileages on intensive West Coast mainline services.

  17. It was nice to see the Shildon staff working on it last time I was there (for a gathering of 7 Deltics) after languishing for some time.

  18. Railways have always been of interest to me, infact more so than the auto industry. The APT/HST/Deltic’s/Western’s etc are so very much part of the British Railway’s bipolar optimisum/gloom of the 1950-1980’s.

    The real shame is the waste of the 1955 modernisation plan and Beaching Report that sent so much stock and infrstructure to the scrap yard so quickly. Most of the advantages gained were thrown away so quickly with such little to show.

  19. @21: The HST must be pretty light then – from my old days with model railway and top trumps the German E03, introduced 1970 for 200kph service had about 10000hp on tap. It would pull very long tradtional passenger trains at 200kph right through the 80s and 90s. My 2nd model engine, given as a Märklin model to my 5th birthday complete with 4 coaches (needless to tell I still have those).

  20. Paul: I should have clarified I meant diesel powered lock’s.

    There were some fabrication errors of the Pendolino of a serious nature wick had to be attended to before they entered service, my old next door neighbour worked at Washwood Heath as a production supervisor. Something to do with the coupling units failing under load stress tests.

    The class 91 loco built by the GEC / BREL alliance was really an 87 in a new suit, but thanks to a redesigned bogie and lower unsprung weight, did not suffer the 86 & 87’s party trick of smashing the track.

  21. The tight British loading gauge doesn’t help tilting trains in this country, as you really notice the affect of the tapered walls on the Virgin Pendolinos which are rather cramped and claustrophobic inside. By contrast, an Italian Pendolino, with it’s wide loading gauge feels far less compromised.

    In some ways the expense on developing high speed diesels was a blind alley, 25kv is the standard across Europe, where diesel traction is restricted to a few quiet branch lines, not major trunk routes.

    P.S. Am I the only one who thinks that top APT looks like a baboon?

  22. To my son’s irritation, I am a train man. Son of a life-long railwayman, for me too it is in the blood. I live in Eastleigh, still a railway town. I have nothing to add to this debate as I know little of the technical side of the HST or APT, although I agree that HST’s strength lies in it’s track availability and it’s Mk3 loading gauge which allows it though most infrastructure. What is refreshing is to see posts of this quality about trains on my favourite car site where we have also had great discussions about Leyland trucks and buses – my other passion. Who says we can’t multi-task 😉

  23. The surviving HST powercar is finally getting restored to running condition, with a Paxman engine :). I’m sure the APT survives as a static exhibit at Crewe. And yes Mikey C, I also think it has a baboon face. It cetainly is fugly.

  24. With regard to the BL/Brel Class 14x Pacers, Kevin (2) is undoubtedly right in all he says. But they are still here. Like the HST they have proved themselves over 30 years in service and that longevity itself is worthy of respect.

    Back to the Class 43 HSTs, one factor in their favour is that they are good looking trains. I’m not sure there is any real correlation between the looks of a vehicle and its success or failure, but it does seem that way at times.

  25. The HST principle and design was even an export hit. Australia runs HST’s based on the UK design, but with a few modifications, and they were also Paxman Valenta powered when new.

  26. “..but the infrastructure of overhead masts, cabling and line side transformers was massively expensive..”

    How come they didn’t just use the third rail electric system as used in the Southern area of BR? Surely that would be far cheaper than building masts, etc.

  27. Confession time.

    The APT was so evident in the news, and so inspiring, that as a small boy I made a point of leaning when running around corners. And I swear it made me faster, too. And encouraged me to adopt the technique relatively early on my bike.

    I bet a modern 8 year old wouldn’t have the faintest idea what rolling stock is (maybe a banking term?) rather than everyone in the school knowing about an exciting new train technology.

  28. “There were some fabrication errors of the Pendolino of a serious nature”

    Other than the routing of the foul water drainage system with the result that the Virgin trains invariably smell like a latrine?

  29. By the sound of it the Pendolinos faults where production related rather than deep routed design flaws that hobbled the prototype APT. Mike – Its the Class 90 thats closely related to the Class 87. It uses the same bogies. The 91 is a completely unrelated design built for high speed services up to 140mph. It was inspired by the APT power car although it shares no common engineering or parts.

  30. @ Adrian

    The reason why the 750V DC third rail system isn’t used nationwide is because it is actually MORE expensive to install and maintain than the 25kV AC overhead system.
    AC can travel farther distances than DC without losing voltage, hence AC requires far less boost transformers along the line than the DC system.

    Why was DC used in the first place then? Basically because in the early days of electric traction, it was easier to control the speed of a DC motor (useful in a train!) than AC. That problem steadily disappeared as the technology of AC motors improved, but because the Southern network was now so vast, it was too expensive to convert it.

  31. The 3rd rail 750v DC system is a low voltage/high current method of electrification adopted by the Southern Railway in the 1920s. It is very inefficient due to power losses and consequently, you need to have sub stations around every five miles, with power cables as thick as your arm. Due to the limits on the current that each train can pull out of the track, this rules out the high power/ high speed type of express train, whilst still being okay for slower lighter commuter type trains.

    The 25kV AC system used with overhead wires is a high voltage/ low current system hence the thin wires that are used to pass current to the rolling stock. Power losses are much less than the third rail system so the sub stations are much much further apart and fewer are needed.

    Whilst the overhead system can be brought down in storms, the third rail system is very prone to icing/ snow in the winter, and this can bring the service to a standstill as was regularly the case last winter.

    BR standardised on the 25kV AC system after nationalisation (in line with most of Europe), but decided to keep the existing third rail system on account of the large route mileage that uses this system (mostly south and south west of London on what used to be known as Southern Region). It has seen limited expansion in the modern era, with the line to Bournemouth in the late 60s and the Hastings line in the 80s being the largest examples.

    Converting the third rail routes to the overhead system would be ruinously expensive as it would be like electrication all over again, and would need bridges raising, new substations, much of the rolling stock would have to be replaced on top of the cost of the new infrastructure itself.

  32. Also worth noting that the Class 91 & Mk4 were what was originally termed “APT-S” or “APT Squadron”, meaning the design that made it into “Sqaudron service”. The APT-P was deemed the “Prototype”.

    What they learnt from the APT-P program was that the loco did not need to tilt for 140mph operation on the WCML, only the stock. This allowed BREL designers to move the loco to the head-end, as per the current Class 91 and Mk 4 formation.

    What was known during the APT-P program was that BREL would not have any build capacity until 1987 for APT-S. This is why the first Class 91 did not appear until 1988. It was during this time that the ECML electrification took place & the decision was made to send APT-S (by then called InterCity 225) to this route. This was in favour to the IMO superior design of Class 89 and Mk 3s.

    Worth noting about the Class 90 is that it was originally going to be designated Class 87/2.

    There is an excellent Channel 4 program from 1988 on YouTube showing the Class 91s development:


    Also the BA 752 on approach to Ringway at the beginning is nice 🙂

  33. There is a yahoo group for the APT. Some of the engineers that worked on it contribute for those interested in learning more.

    Excellent article from Mike.

  34. ELECTRIFICATION FTW! As mentioned above the APT project wasn’t really a waste, the main problem in reality being the infrastructure upgrade required @ the lack of funding therein.

    Shortly (within 2 years) all control of the OHL and 3rd rail will be controlled with just “2” ECR’s (Electrical control rooms) one in Manchester, the other in 3 Bridges. So the odd’s of me being an ECO (Electrical control operator) again are pretty slim…

  35. What an excellent article, it makes a nice change to see something about the APT project that’s not full of regurgitated media produced rubbish.

    I must declare an interest here as I was the Tilt System Development Engineer on the gas turbine APT-E and did some work on the tilt system of the 25Kv APT-P as well. Just last month I was pleased to take a Class 390 Pendelino south from Glasgow Central to Euston on the 30th anniversary of the APT-P’s first run, on the 7th December 1981. I was on that run too, but it left at 0700 hrs whereas the Virgin Pendelino left 30 mins later. APT-P was still faster though, getting to London about a quarter of an hour earlier than the present day Class 390, but we did get up to 138 mph back in 1981!

    One thing that isn’t quite right above is the bit about BR patents being sold to Fiat for the Pendelinos. That’s not quite how it happened and there were no patents involved anyway. Both BR and Fiat were working on tilt technology in the early ’70s, using completely different systems to achieve similar results. The BR system was servo-hydraulic whereas the Fiat system used electric screw jacks. When BR was privatised various bits of it were sold to other European organisations, and the R&D section went to a different buyer to the manufacturing part. In time, due to various mergers and buy-outs, the APT-P tilt technology ended up with what is now Bombardier, who made the currently in service Super Voyager diesel trains and so that technology still exists although currently Virgin and XCountry don’t run them in tilting mode for some reason.

    For those with a further interest I’d recommend two web sites, http://www.apt-e.org/ for the APT-E train and http://www.apt-p.com/aptindex.htm for the APT-P Train. Both trains still exist as mentioned above, and I’m pleased that I’m still involved with the APT-E Support and Conservation Group in looking after ‘our’ train at Shildon in Co, Durham.

    To futher my Austin-Rover connections I spent the first 9 years of my industrial life at Pressed Steel Fisher at Cowley in the R&D Dept, and after my time at BR I spent many hours, days and weeks installing and maintaining large and small test rigs at various A-R sites around the country.

    Small world.

    Kit Spackman

  36. On a recent holiday in the UK and Europe – the UK has the worst railway network – how is this? The UK invented trains yes? The french and german train systems we used were cheaper, faster and more comfortable than anything in the uk…..why?

  37. Thanks very much for that Kit.

    I will drop you a more formal e-mail in the near future. As it would be great to press flesh maybe at the NRM in Shildon whenst I’m next in Darlington!

  38. @Dave – The French and German railways are far better than in Britain because they have enjoyed far more investment, simple as that. The tide does seem to be turning though. As well as the recent go ahead for the High Speed 2 line between London and Birmingham/Leeds/Manchester, there are also major electrification programmes for the Great Western main line to Bristol/Cardiff, the Transpennine route between Liverpool/Manchester/Leeds/York and between Glasgow and Edinburgh. Shouldnt forget Crossrail eaither. Many years since Britains Railways have enjoyed such a level of investment – if ever!

  39. I agree with Paul, the railways are making a massive comeback and for all it’s fashionable to knock the Coalition, they are doing far more than Labour did in 13 years in power. I look forward to the day when I can get from Carlisle to London in 2.5 hours.

  40. Some comments on what has gone before!

    Mike Humble’s very interesting article on the APT-E and BL turbines was drawn to my attention by a post on the APT-E supporters’ mailing list.

    The APT project wasn’t shelved before the electric version started to be developed. The APT-E (experimental)was always intended to be followed by the APT-P (prototype) version and then APT-S (squadron)for full passenger service. I was there and had connections with both E and P versions.
    Mike rightly stes that the HST was a “rival” project, initiated by the Director of Mechanical & Electrical Engineer’s (DM&EE) department in competition with BR Research’s APT.

    The DM&EE actually had control of the APT-P project, taking on most of the engineers who had worked on APT-E.
    Kevin, in your list of Great Names, don’t forget BREL (British Rail Engineering Limited)who assembled much of that age’s rolling stock, to DM&EE designs, including HST and APT.

    And Kevin, aren’t you joining the ‘mockers’ when you make those derogatory comments about the Pacers. The Class 142 was developed from the high speed freight vehicle (HSFV1) developed by the same team which worked on APT suspension. The suspension used was actually less sophisticated than that of HSFV1 but, in general, the Pacers ride better than the earlier diesel units. They nod a little on points and dipped rail joints but, at speed on plain track, they’re pretty comfortable.

    AllFormsOfMotoringFan, I remember a Rover/BRM entered for the le Mans 24 hour race several times. A series of road cars had also been produced, from the early prototype Jet 1 through to the more developed examples T2, T3 & T4.

    Andrew, “we never had the infrastructure for the APT to run on”! The whole idea of the APT was to achieve the high speeds of TGV and Shinkansen on existing infrastructure. It could “run on existing tracks at high speed with no changes to the infrastructure” at much higher speed than HST, which could only achieve its high speed exploits on the straighter parts of the ECML with a cut-down set. I actually experienced APT-P train running uphill from Gretna towards Beattock – a very curvaceous section of line – at a constant speed of 155mph. And it was perfectly comfortable!

    Mike, the Washwood Heath Plant (formerly Metro Cammell) was Alstom (formerly GEC), not Bombardier.

    With regard to retrofitting of tilt equipment to Class 91s, there was an equipment cabinet inside the loco labelled “Tilt Pack” – empty of course!

    750Vdc third rail has obvious advantages for suburban electrification as there are not the clearance problems and subsequent bridge-rebuilding requirements of the 25kV overhead system but would the HSE, if it had existed then, have allowed the system to be adopted? One idea put forward to overcome the icing and safety problem is to adopt a side-contact system – like DLR – which could be installed in stages, with both types of shoe equipment fitted to some trains.

    Finally, Mikey, I don’t think that the APT-P train looks like a baboon. It’s obviously a matter of personal taste – I think the APT is better looking than the HST!

  41. I should have added that the “staff” seen working on APT-E at Shildon would be the APT-E Group volunteers and, further to Class 91s, as well as the prospect of adding tilt the motor/transmission/gearbox system owes much to APT-P.

  42. Gerry, it’s the APT-E that looks like a baboon (IMHO), not the APT-P which looks quite attractive!

    Kit, I hadn’t realised that the Super Voyagers used technology derived from the APT, especially as at the time they were designed Bombardier hadn’t yet merged with Adtranz, and thus had no connection with the former BREL Derby. The design of all the Voyager and Meridian trains was compromised by the need for the tapered bodyshell to enable tilting, so it would be terrible if they didn’t use it!

  43. The standard 3rd rail system has a speed restriction due to the limitations of the shoegear, over a certain speed it would loose contact too often.

    The reason the APT had to have the pantographs in the middle, rather than at the ends was due to a similiar risk of loosing contact when running at high speed.

  44. I think the stagger of the OHL would need to be controlled too. Gerry, my point on infrastructure being that until recently we had HST routes limited by the humble token (take a bow Moreton in Marsh where the signaller has to run down to the guard with the token!), points with speed limits across them, narrow bridges limiting speed across them etc. Even silly things such as platform lengths.

  45. OHLE stagger isnt a problem either. Pendolinos operating over the WCML tilt in the same way APT was meant to. The OHLE was “super tensioned” in the 1970s in anticipation of high speed running and over most of the line remains in that condition today. The pantograph on Pendolinos and APT compensate for vehicle tilting to remain upright and in contact with the contact wire.

  46. Richard – More specifically, the APT-P had two power cars because one couldn’t provide sufficient power to achieve the desired speed and they had to be together because it had been established that two pantographs caused current collection problems due to the mechanical waves set up in the overhead system by one pantograph causing serious disruption to the other at high speeds. To use only one pantograph there had to be a high voltage connection between the two power cars and it was not thought possible to run a HV cable the length of the train, so they were together in the middle. Pendolino actually solved the single pantograph problem with a HV cable running the length of the train, with flexible HV connections between each car!

  47. I would like to add the following to the discussion of the Southern third rail system. Although and ‘Southern Man’ by inheritance I have always questioned the further expansion of the third rail system post 1960. These words are from a book shortly to be published as an e-book or printing on demand.

    “Views of a Changing Railway: Edward Hopper – Railwayman from 1925 to 1968”

    The electrification was carried out as economically as possible, setting a pattern for the next forty years. Many of the new electric trains were converted from old steam hauled stock, so the passenger environment did not change. Some of the journey timings were not much quicker although Walker made a significant change to the service pattern with the introduction of interval timetables. His target was for an electric train every twenty minutes suggesting that this would do away with the need for the passengers to have a timetable, being happy to wait for the next train. On many lines the off-peak interval was every thirty minutes, but of course as two routes joined together on the approaches to London the intervals were reduced. While the interval service is often billed as a public relations exercise it also had an important technical aspect. The regular intervals between trains maintained an even demand for electricity from the railway’s own powerhouse at Durnsford Road. This is a good example of the interests of both the passenger and the railway engineer being in accord.

    However, the Southern’s cheap and quick installation of 650v dc third rail posed problems. Some eleven years before the London and South Western Railway embarked on suburban electrification Professor of Physics, Silvanus P. Thompson of the City and Guilds of London Institute (and a Quaker) wrote that “the live rail is itself already an obsolete device. It is an engineering blunder. I would therefore ask whether the time is not right for public opinion in some effective form to step in and prevent the railway engineers of England from committing our railway system any further to this dangerous and unnecessary device.”

    Unfortunately, the selection of the top contact third rail has left the railway with a problem. While the third rail system is widely used on metro, underground and suburban systems around the world there is no other mainline use of this technology. It is also the most dangerous version of the technology, the top contact making it impossible to cover the live rail with a protective sheaf as is done on bottom contact systems. The cost of keeping the rail ice free in winter is small by comparison to the cost in terms of human lives as by the twenty first century the public knows less and less about the ‘Southern Electric’ and the dangers of trespassing on these tracks. The humorous Southern slang of “to get a touch” or the warning when climbing down from a locomotive to “watch out for the fourth step, it has 650volts in it”, were ways the staff kept the danger in mind. Walker’s decision to electrify was possibly one of his best, but his choice of top contact third rail was his worst decision. Working at Waterloo, Father was steeped in the principle of electrification being the central focus for the railway development, seeing it as the best way to regenerate service quality and an increase in passenger numbers on any railway.

  48. Some of the issues relate to the disease that so often hits UK projects, and that is not being able to think long term, or accept that a profit will not be available today! Whilst the APT-P was a prototype, a fact that many forget, much of its technology was moved to the Class 91 and train formation, the Pendolino trains, etc., therefore, as a prototype, benefit was gained for what followed. However, by not providing the braking capability of the APT-P to stop from 140 mph in the existing signalling distances, the Class 91, therefore IC225 sets, were never going to be used at 140 mph.

    Consider that the East Coast Main Line still uses 125 mph diesel trains for those sections not electrified, such as beyond Edinburgh, across to Hull and Sunderland, and you are back to 125 mph diesel trains using much of the same route as IC225 electrical trains, therefore, these 140 mph capable electric trains are unlikely to ever be used as intended.

    To allow 140 mph running on the East Coast Main Line would either require IC225 trains to have upgraded braking systems, the 125 mph diesel trains similarly upgraded for 140 mph running also with new braking systems, or in-cab signalling to allow existing IC225 trains to rub at 140 mph, when the line clearance ahead would allow this increased speed.

    It could also be argued that we persist in trying to force a mixed traffic, rather old railway to improve dramatically, whilst other countries have instigated a dedicated high speed railway as a better way forward but, as usual, doing anything in the UK is significantly more expensive than other countries, therefore, we end up going from one major compromise to the next.

  49. The ability to run at 140mph is not connected to braking efficiency. Both the IC225 sets and Pendolinos where specified to run at speeds in excess of 140mph and have braking systems to permit this. The issue is the ability to read and react to lineside signals at that speed. Cab signalling is now deemed a requirement to increase speeds. This will come eventually with the introduction of ERTMS, currently prioritised for the Great Western Mainline and the East Coast south of Doncaster. 140mph would also need major revisions to timetabling and business case analysis now suggests only limited benefits to moving from 125 to 140 with only minutes saved on the majority of end to end journey times as a result of going 15mph faster.

  50. Had the APT succeeded and the WCML was upgraded for 155 mph running, there is a possibility my current journey from London to Carlisle would take 2.5 hours instead of 3h 20 m at present, ironically with the same technology. It’s likely now a second generation APT would be serving the route.

  51. The image of the APT-E shown arriving at St Pancras is COPYRIGHT of the Rail Archive and has been used WITHOUT authority or credit – PLEASE REMOVE -pending further action by the owner of the copyright! 10 June 2016

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