Railnews November 1980

RAILNEWS November 1980 Special Souvenir Extra

WITHIN the next few weeks a train will pull out of Glasgow Central station for Euston and mark the culmination of 13 years' endeavour by BR research and design teams.

Making its debut in passenger earning service will be BR's Advanced Passenger Train, of such revolutionary design that its performance will be watched all over the world.

Its introduction comes as passenger rail travel celebrates its 150th anniversary and it heralds an advance in railway transport development every bit as important as the events of the 19th century.

For this train, which still retains the name "advanced", is in every sense a new concept, even when compared with the 125mph HST which is performing so successfully on the Western Region and East Coast mainline.

Commercial sense

Critics see the 13-years timescale from concept to introduction into service as excessive but it was only about seven years ago, in January 1973, that the BRB design teams were given the job of designing the prototypes, following the tremendous technological achievements of BR's Derby technical centre, which proved the feasibility of the project. And these design teams had to start again - virtually from scratch - when it was decided, because of the first oil crisis in 1974, to abandon the use of gas turbine engines to drive the train.

As it made commercial sense to launch the train on the heavily used, but severely curved, Euston-Glasgow route - already electrified - it was decided to employ electric traction.

Since then no fewer than 8,000 detailed drawings have been prepared in the design offices at Derby.

Rigorous testing

During the experimental period each new design, and the component materials, have had to be thoroughly tested, either on a test bed or on proving trials.

As problems occurred so they were dealt with, using the latest testing facilities and techniques, until the designers were satisfied they had a product to beat the world.

During the trials the prototypes were subjected to the most rigorous testing ever carried out on rolling stock - testing which proved the effectiveness of all the innovations.

The hydrokinetic, or water turbine, brake, which can stop the train smoothly from 150mph within signal distances, ran 190,000 miles under a conventional coach operating in regular mainline service.

Even now performance of the three prototypes is being monitored and modifications made where necessary, to be embodied in the design for the squadron of 60 trains which BR has requested the Department of Transport to authorise.

Such is the faith of BR in this new train; a faith built not only on the wonder of the design but on the capabilities of the hundreds of railwaymen and women who will build, maintain and drive them, day in and day out, to levels of efficiency undreamed of only a few years ago.

There is no doubt that the introduction of APT will have as big an impact on public travel as the advent of the steam train 150 years ago. From the APT achievement will flow benefits which will be shared and enjoyed by thousands of passengers. The railway industry will notch up a major prestige triumph.

And the world will be watching.

Pathing the APT called for SPOT-ON PRECISION

CLOSE headways and precision timing were required when LM's chief operating manager had to time the daily APT from Glasgow to Euston and back in four hours and 15 minutes each way. It brought plenty of headaches for the staff involved.

Timetable production officer Martin Talbot explained: "Slotting a 125mph train into an intensive 100 mph service is tricky enough."

"But to run it at specified commercially acceptable times with minimum disruption to existing services brings real problems and calls for spot-on precision."

APT is planned to leave Glasgow Central at 07.00, call at Motherwell and Preston and arrive in London at 11.15.

In the reverse direction if should leave Euston at 16.30 making the same stops and arrive in Glasgow at 20.45.

Tight spot

Responsible for planning its paths is passenger planning and timetable officer John Batchelor:

"Our first tight spot was Weaver Junction where APT preceeds the 09.05 from Liverpool by only 5½ minutes."

"Also we had to start the 07.16 from Carlisle five minutes earlier so it can be diverted to the slow line after its Crewe stop to allow APT to pass on the fast." There is close headway at Rugby where APT passes only three minutes ahead of the 09.30 Wolverhampton to Euston service, and she is due in London only six minutes after the 06.27 from Holyhead, so spot-on running of all trains is essential."

"Mid-day engineering possession time of the fast lines has had to be reduced to avoid crossing APT to the slow and thus spoiling the four hours ten minutes schedule," said Mr Batchelor.

Equally tight timing is required for the return journey. To allow the 16.30 departure from Euston, the former 16.25 to Manchester now has to depart at 16.35.

At Rugby APT is only 8½ minutes behind a Birmingham train and the 16.00 from Euston is diverted to the slow line at Milford and Brocton, near Stafford three minutes before APT flashes past on the fast.

Minutes count

Four minutes separate her from the preceding Paddington to Liverpool service at Weaver Junction, and at Carlisle the 15.00 from Euston terminates only five minutes before she passes. Throughout the planning, Mr Batchelor has kept in close touch with his opposite number in Scotland, Jim Summers. North of the Border. problems arose included finding a path through the intensive Trans-Clyde services and delayed arrival of the 22.15 sleeper from London by ten minutes at Glasgow to allow platforming of APT for its 07.00 departure.

"Similar problems were encountered in planning for the second APT which is to start a round trip from Euston early next year," said Mr Batchelor.

"Local train as well as main line service adjustments have had to be made, but generally all four paths have fitted in remarkably well."

Full fleet

"The four APT services give passengers a close following alternative service should a set be unavailable, avoiding the need for expensive standby resources."

"A fleet of APTs permitting full 125 mph services would make our task much easier and give a second to none service on the West Coast route."

For the man in the cab C-APT ensures safety at any speed

SAFETY has been paramount in the minds of the designers of APT.

A revolutionary aid to drivers, based on micro-processors, is the C-APT, a speed limit advice mechanism in the cab.

The men who drive the APT will also drive conventional trains over the same routes, yet APT is allowed to exceed existing speed limits by a substantial margin. To prevent confusion, the higher limits are displayed automatically in the APT cab. This advisory system (C-APT) leaves the driver firmly in control of the train, but gives him a digital advance warning on his desk of the higher APT speed limits.

On the track, beacons, called transponders, store permanent speed limit information in coded form. Sealed in glassfibre re-inforced cases the transponders, containing electronics and a loop aerial, are waterproof and need no external power supply.

The transponders are powered by a radio beam transmitted by a loop aerial under the front of the train. A coded message is re-transmitted by the transponder and fed to the train-bourne processor unit. Micro-processor circuits check the validity of the code and display the approaching speed limit to the driver.

When the train approaches a speed restriction the display changes to the new limit at the appropriate braking distance. An audible warning sounds which the driver must acknowledge, otherwise the brakes are applied automatically.

The driver selects a suitable braking rate to bring the train down to the new limit displayed. At the start of the speed restriction an indicator light on his desk is briefly illuminated, while at the end he receives a short warning sound to alert him to the higher speed.

C-APT has to fail safe so transponders are bolted to the sleepers at intervals of 1km or less, if the equipment fails to detect a transponder after 1km, the display goes blank and an audible warning is initiated which must be acknowledged by the driver. With a blank display the driver reverts to conventional line speeds.

To eliminate the risk of wrong speed limits being displayed, all the train-bourn equipment, except for the display, is duplicated, while the electronic system has an inbuilt self-checking routine.

A secondary use of C-APT is to close air intakes when approaching tunnels to prevent ear discomfort to passengers.

APT will be able to run through the station at Berkhamstead, on a 1,170m radius curve, at 120 mph compared with the 90 mph restriction imposed on loco hauled trains.

It all began with a BREAKTHROUGH

THE APT originated from research carried out in the mid 1960s when the problem of instability or "hunting" of rolling stock when travelling at high speed was conquered by BR scientists.

This was a breakthrough that could be exploited by designing a train to run on existing tracks faster than the then maximum of 100 mph.

The commercial value of this was reinforced by the considerable growth in passenger traffic which resulted from the reduced journey times that stemmed from the electrification of the Euston/Manchester/Liverpool routes in 1966.

Studies concluded that considerable savings in journey time could be achieved, without costly investment in major new track work, by increasing speeds round curves.

Roughly half of BR's major routes are made up of curved track, and half of this total is of relatively sharp radius.

As average speeds of conventional trains tend to be determined largely by speed restrictions round curves, an increase in maximum speed alone would only produce limited gains on all except the straightest routes.

This led to the concept of a train which could reduce journey times by a combination of both a high maximum speed, and a high curving speed.

To overcome the uncomfortable effect on passengers that this would cause, the idea of a tilting train was developed.

By titling each vehicle inwards on curves by means of a special suspension, the outward pull on passengers due to centrifugal forces can be fully counter-balanced, not only maintaining comfort, but enhancing it in comparison with conventional trains.


The idea of a high performance tilting train represented a significant advance in railway innovation and this was recognised in its name, the Advanced Passenger Train.

The train's major objectives were to:

To meet these exacting requirements major technical innovations were needed in the design of bogies, suspension, tilt systems, transmissions, braking systems and vehicle structures.

All needed extensive research and development support, to develop the theoretical background, to gather data about the track, aerodynamic and acoustic inputs and to design and test equipment so that ideas could be proved in engineering terms.

Special labs

The first stage of the project was authorised in 1969, with the Department of Transport agreeing to meet half the cost.

A research and development programme was orientated around the design, construction and testing of an experimental train, called APT-E. Extensive laboratory facilities were built at Derby and a special test track laid at Old Dalby.

In addition other experimental vehicles were built for testing particular items of equipment.

APT-E was tested systematically in the laboratory and on the track, covering over 23,000 miles from June 1972 to April 1976. All the innovations came through with flying colours.

Speed runs

It was APT-E that convincingly demonstrated the ability to run at higher curving speeds when it tackled the 99 miles between St Pancras and Leicester, a route full of bends. It completed the run in 58 minutes at an average speed of 101 mph, compared with the best service timing of 1hr 24mins.

Its mission completed, APT-E was moved to the National Railway Museum at York for an honourable retirement.

Design work on the second stage of the project, responsibility for which had now passed to the CM & EE, was authorised in October 1973, again with a 50 per cent financial support from the Department of the Environment, and a year later authority was received to build three prototype trains, together with test equipment and production and maintenance facilities.

Construction of the first power car was completed by BREL at Derby loco works in June 1977, and the first rake of trailer cars was delivered from Litchurch Lane a year later.


By November last year all three trains were complete.

In September 1977 track testing of the power cars up to 125 mph started and was followed by the trailer rakes in July 1978.

The first prototype (APT-1) was marshalled as a 2 + 6 formation in February 1979 and moved to its base at Shields depot, Glasgow, to start its primary series of proving trials. These finished last February.

The second train (APT-2) was marshalled in December 1979, and is carrying out an extensive programme of driver training, while the third (APT-3) since last March has been making frequent runs between Glasgow, Preston and Euston (without fare paying passengers to build up further mileage, reliability and staff experience prior to its entry into commercial service.

In addition to track testing an intensive programme of static testing has been carried out on train equipments and systems, particularly those related to passenger environment.


Prolonged endurance tests and accelerated life tests, using fully-fitted vehicles, have involved continuous running and cycling of the following systems: air conditioning, tilt hydraulics, inter-vehicular gangways, automatic external and internal doors, chemical toilets and washbasins.

This work has enabled defects to be identified and corrected ahead of passenger service.

The development and intensive testing programme has now proved the major technical features of APT-P. No problems have arisen which would invalidate the technical correctness of the train.

Those that have been encountered have been resolved and vehicles are being rectified.

It is estimated that the development of the three prototype trains will amount to £32.6 million. At constant price levels, this is 26 per cent less than originally authorised for the project.

Now meet the men who'll keep APT on track

Expert training for fitters in a 'space age' job

ALTHOUGH the men on the footplate of Britain's fastest train will undoubtedly continue to catch the public eye, those who have the less glamorous task of maintaining APT are every bit as important.

When APT comes into passenger service, it will be stabled overnight at Glasgow's Polmadie carriage servicing and maintenance depot.

Simple maintenance tasks will be performed there. Anything heavier will be tackled at nearby Shields electric traction depot, which is equipped with a 20-tonne overhead crane and a modern drop pit for removing axles.

To the uninitiated, the check list for APT's regular servicing examinations looks like a written countdown for a Cape Kennedy moonshot.

But one of the major objectives in the APT design programme was to make it compatible with existing maintenance techniques, thereby keeping extra costs to a minimum. This has been accomplished, and fitters would immediately recognise many of the items on the check list as being similar to those on electric locos and the HST.

Nevertheless, Space Age developments such as the APT's sophisticated tilt mechanism or its hydro-kinetic braking system are truly unique. And fitters must have the same easy familiarity with them as they have with the components found on 20-year-old locomotives.

Unfortunately, not enough Glasgow fitters have the required degree of intimacy. The pre-production APT test programme with its constant running to build up mileage, has hampered the arrangement of schedules for on-the-job training. But Scottish Region CM and EE has made provision for this as Jimmy Logue, area maintenance engineer at Shields, points out.

"The pre-production APT has been based here during its test programme and is still under the jurisdiction of the commissioning team," he says.

"Their long association with the train has given them the sort of expertise that will be invaluable when the train comes into service."

"Consequently, we envisage that the team will be split into two parts. One will continue with its development work. The other, consisting mainly of ex-Shields depot staff who were seconded to the commissioning team, will liaise with foremen in the supervision of the fitters. Thus we'll have a team of experts available while more are being trained."

Meanwhile a programme of intensive training courses for APT maintenance staff is already under way utilising classroom facilities at Shields depot.

"Some months ago we ran basic induction courses for staff at Polmadie and Shields depots," says technical training engineer Grant Reid.

"These were conducted in the classroom and as often as possible on APT itself. They covered the important aspects of safety as well as equipment, layout and configuration. The intention was merely to let staff know where everything on APT is located."

"Since then we've had problems getting access to the train to facilitate specific on-the-job training. The APT comes in complete rakes of vehicles and you can't separate one vehicle from the rest of the train."

"The train has seldom been in the depot as the commissioning team have had to concentrate on building up mileage."

"It would be impractical to take trainees on a test run - they would only get in the way. The net result is that it has been difficult to arrange for the train to be in the depot in advance so that we can fix up a training schedule."

Despite this, the CM and EE people have managed to complete a detailed course on the APT's complex air-conditioning system. Week-long courses on the catering equipment, servicing and testing are currently under way.

Others in the offing are for APT "A" and "B" servicing examinations and special component fault finding. Subject to the APT's availability, training will be completed by the spring of 1981.

Praise from China

President Hua of China, on a visit to the Railway Technical Centre at Derby, said of APT:
"It is the most impressive piece of technology I have seen anywhere in Europe."

RAILNEWS November 1980 Special Souvenir Extra
© RAILNEWS November 1980.
Drawings by DAVID GIBBONS.

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Last Revised: 19.01.2019 12:59
by R G Latham
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