Class 221 testing and operations

Between 2001 and 2004 the class 221 Super Voyagers underwent test and commissioning running on the Monk Bretton branch near Wakefield and on the East Coast Main Line (ECML).

The class 221 units were built by Bombardier at their Horbury (Wakefield) and Bruges (Belgium) plants and consisted of 5 cars each having an underslung 750HP QSK19 Cummins engine driving an alternator which fed two longitudinally-mounted traction motors each driving one axle per bogie via final drives and cardan shafts. The units also featured rheostatic and friction braking and were capable of tilting at up to six degrees.

The class 220 units are known as Voyagers and are non-tilting but the tilting class 221 Super Voyagers have the same tapered body profile.

Serco staff were involved with all the initial test running under a specially written Class 221 Railway Safety Case on the Monk Bretton branch and on the ECML, the WCML and on the GW between Oxford and Banbury. The units were delivered by rail from Horbury Works to Crofton Depot which used to be a track assembly depot - see class 220 page for details and pictures of Crofton.

The depot is still in use today servicing Class 170's and 222's as well as Voyagers and latterly the class 180's. Horbury Works has now closed.

Serco undertook all the formal Acceptance Testing and a multitude of train operations on the class 221 fleet including commissioning runs on every unit, TASS commissioning and tilt testing etc.

Prior to commencing running tests the units underwent static testing at the RTC, Derby.

Click on the picture for a bigger image - all photos are the authors unless otherwise credited

Sway test An unidentified class 221 shown in the EDU undergoing a sway test

Author's collection

Tilt test The unit shows off its tilting ability in the safety of the workshop

Author's collection

Commissioning running

Apart from the low speed running at Monk Bretton (see class 220 page) further commissioning runs took place on the ECML as far north as Edinburgh. In addition various round trips were undertaken from Crofton to York, then to Edinburgh, across to Carstairs, down to Carlisle and Carnforth and back via Bolton and Manchester Victoria  to Crofton .

Inside Horbury A shot from the cab of a 221 unit as it negotiates the workshops at Horbury to gain access to the yard. Calder Bridge Unit 221106 is pictured at Calder Bridge Jcn. between Crofton and Wakefield Kirkgate en route to Edinburgh in the summer of 2002
221-114 Newcastle 221114 at Newcastle station after a run from Crofton sometime in March 2002 221 109 at Berwick on Tweed After a run from Crofton 221109 awaits departure from Berwick-on-Tweed on the return trip.
221 109 at Edinburgh Waverley 221109 pictured at Edinburgh after a test run from Crofton.

Further test running

Testing also took place in Belgium and in France with 221101 fitted with a Load Measuring Wheelset in February 2002

Here are a few photos courtesy of Ben Jones

221101 crossing the Viaduc de Lamothe near Souillac on the Paris-Toulouse main line in February 2002 221101 at Brive La Gaillade

221101 at Brive La Gaillade 221101 at Brive La Gaillade

Some reprobates from BR Testing Section during a sway test on 221101 in Bruges  

Tilt testing

By August 2002 tilting trials were well underway with unit 221101 on the West Coast Main Line (WCML) between Carnforth and Carlisle.

This part of the WCML was fitted experimentally with Tilt And Speed Supervision (TASS)  balises for test purposes. This allowed the Super Voyager test train to exceed the normal line speed (Enhanced Permitted Speed) at certain locations and EPS signs to this effect were erected along the route.

221 & Pendolino at Tebay At the end of July 2002 unit 221101 is pictured at Tebay in the company of a Pendolino set. Both trains were being prepared for separate overnight high speed tests between Tebay and Carlisle 221-101 Preston 221101 pictured in the disused platform 7 at Preston en route to Carlisle on 1st August 2002
221-101 Crofton headshunt On a misty August morning 221101 awaits in the headshunt outside Crofton depot ready for a trip to Carlisle 221-101 Carnforth 221101 stands in the Up & Down Goods Loop at Carnforth after a run from Carlisle on 3rd August 2002
221-101 Carlisle Unit 221101 stands in platform 1 at Carlisle having just arrived from Carnforth on 3rd August 2002 Driver's desk The driver's desk of a class 221 showing the small instruments and the large gap left for ERTMS driver's display - one day!
 Upperby 221101 is pictured on the Goods Lines outside the former steam depot at Carlisle Upperby whilst adjustments are made in connection with the testing programme 221-101 Courock junction The driver of 221101 changes ends at Courock Junction during a turning move at Carlisle on 3rd August 2002
221-101 leaving Carnforth 221101 departs Carnforth for Carlisle on 3rd August 2002. It was during these trials that the train ran in tilting mode, the first time a tilting train had operated in normal traffic in the UK  for almost 18 years. 221-101 LowHouses (S&C) Following overnight tests 221101 is pictured on the S & C at Lowhouses when returning to Crofton on 13th October 2002
Hellifield 221101 waits for the road at Hellifield on its way back to Crofton later that morning Tebay It was still undergoing tests when pictured in the sidings at Tebay on 17th November 2002

Other tests also took place on the ECML

Bridge Resonance

Underbridge resonance is a phenomenon that occurs when the frequency of loading from rail vehicles matches the natural frequency of a structure or particular elements of a structure - namely a rail underbridge.

Incidents of ballast moving on underbridges when being traversed by TGVs on SNCF lead Railtrack to instigate a test series on several new built DMU's (including class 180 and class 221) although realistically the design of underbridges in UK was different from SNCF and the fact that TGV's were articulated seemed to have passed Railtrack by.

Unacceptable accelerations and displacements of the bridge deck can occur under these conditions leading to ballast instability and consequential deterioration of track quality. Some limited testing was carried out over instrumented underbridges between York and Ferryhill but as far as I know it showed there was very little effect from a five car DMU.


Darlington The driver is seen unlocking the cab door after changing ends at Darlington with the pucker 5-car version of 221101 on 5th March 2003
221 126 221126 at Northallerton on 4th May 2003 whilst undertaking test work on ECML in connection with bridge resonance testing.
221 126 at Ferryhill 221126 is pictured on the Up Goods line at Ferryhill on 4th May 2003 awaiting a run back to Northallerton during  bridge resonance testing

TASS testing

The line between Banbury and Oxford was one of the first to be fitted with Tilt And Speed Supervision (TASS)  balises for test purposes. This line was usually limited to 90 mile/h but the Super Voyagers could run at an EPS of 110 mile/h. However this was later reduced to line speed for passenger service and rumours have it that the tilt system is now isolated.

During the spring and summer of 2003 TASS commissioning took place on the route between Oxford and Banbury, unfortunately at night! The run down from Central Rivers depot in the early evening was usually straightforward but we often got stuck somewhere on the return journey which was invariably after midnight.

Ironically the beacons were re-programmed back to 90 mile/h and lately Voyagers have had their tilt systems isolated

221 109 plus HST at Hinksey Yard 221109 stands in the yard at Hinksey just south of Oxford on 10th March 2003, as an HST passes. 221 111 Banbury On 11th March 2003 unit No: 221111 waits in the Goods Loop at Banbury for a test path south to Oxford 
221111 heading south 221111 in 4-car formation passing Heyford Station heading for Oxford on 11th March 2003 at 11.04am

Author's collection

221111 heading north 30 minutes later it was heading north back to Banbury

Author's collection

221111 heading north 221111 approaching Heyford Station heading for Banbury later in the day

Author's collection

In service

Northallerton On the ECML two unidentified class 221 sets pass Northallerton with an Up cross country service on 4th May 2003 Milford An unidentified class 221 heading north from Milford Tunnel on the Midland line on 6th May 2004
Bullbridge Up service  An unidentified class 221 set heads south towards Toadmoor Tunnel on 7th June 2005 Broadholme On 27th June 2005 a 221 set is pictured on a Down service at Broadholme, between Belper and Ambergate.
Ambergate On 1st July 2005 an Up Cross Country service crosses the River Derwent and the A6 at Ambergate Wingfield Tunnel An unidentified class 221 set heads south from Wingfield Tunnel on 11th May 2006
Sheffield 221124 at Sheffield with an Edinburgh service on 13th July 2006 Warrington 221127 arrives at Warrington Bank Quay with an Up service on 11th September 2006

Further testing

In July 2007 trials were undertaken utilising a class 221 to assess new brake pad material for both the 221's and 220's. The pads had already been proven on the dynamometer rigs at the manufacturers and the on-track testing was to validate their performance in traffic.

The trains were once again based at Crofton Depot, Wakefield which was very convenient for the ECML.

Back again Four car Super Voyager 221142 waits on platform 4 at Darlington for a return trip to York in connection with tests on new brake pads on 17th July 2007.


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