Courtesy Roland Turner
Courtesy Roland Turner
Peter Watson
IC225 and Class 91 commissioning - Part 2 of 9
Early days
|
The locos were intended to run at up to 140 mile/h (225 km/h - hence the name IC225) with new Mk4 coaching stock in push-pull mode achieved by having a Driving Van Trailer (DVT) at the opposite end of the rake and a Time Division Multiplex (TDM) control system using dedicated screened through wiring. |
|
As the first ten locos were delivered in 1988 before the Mk4 coaches and associated DVT's, eight HST power cars were converted to act as 'surrogate' DVT's and equipped with TDM, conventional buffers and drawgear. These comprised:-
Once the loco's early teething troubles were overcome during the running with the Mk2 stock, testing was extended to include a 5-car rake of Mk3 sleepers which could be run in push-pull mode with the HST DVT by use of a screened cable running the length of the train. This was most important with respect to the train's braking as the control system released and applied the brake from the 91 and the DVT. Hence when being hauled by the 91 the E70 brake valve in the DVT was held off by the TDM and any break in circuit (or a fault) meant a remote brake application from the DVT. Early days testing the locomotives and surrogate DVT's Click on the picture for a bigger image - pictures are courtesy Paul Wesley unless otherwise credited |
|
|
A surrogate DVT 43014 in the loop at Doncaster waiting for a path back to BN on 8th August 1988. This was when the DVT, which had a defective power unit at the time, was used purely as a driving cab |
|
On the other end is 91004 coupled to the R&DD's Lab 6 'Prometheus', the dedicated OHLE test vehicle |
|
|
On 16th August 1988 91004 propels its train away from Doncaster en route for BN |
|
A test train hauled
by 47655 passes the box at Everton Crossing (north of Sandy) on the ECML
sometime in 1988. The first vehicle is the R&DD's Lab 6 'Prometheus' Courtesy Roland Turner |
|
|
Later in the day an
unidentified class 91 propels the train south with Prometheus and 5 Mk3
sleepers plus surrogate DVT leading Courtesy Roland Turner |
|
43014 passing
Alexandra Palace station with the Mk3 sleeper test train Peter Watson |
|
Initially the DVT's power unit was only used to supply ETS for the Mk3 coaches, as they differed from the Mk4's, and hence the engines were only running at approx 1000 rpm, just above idling. However, prolonged use of the power cars in this way lead to an excessive build up of un-burnt fuel in the silencers and this eventually lead to fires. One occurred at Hornsey, just outside Ferme Park and this brought the OHLE down too. After a repeat performance it was decided that the engines should be powered up as normal and this then meant that the test trains had a combined available power of over 7000 HP. A modification to the TDM control s allowed the engine to be controlled from the class 91 and an increase in speed up to the maximum of 125 mile/h was accomplished with ease!, Transit moves and tests There were a number of tests and trials in the early days of the project, not to mention transit moves, light engine tests etc Click on the picture for a bigger image - all pictures are the author's unless otherwise credited |
 |
The locos were delivered under their own power from Crewe. Pictured at Stonebridge Park at the bottom of the WCML on 16th July 1988 is 91002. The loco was on its way back to Crewe for modifications and the train crew were waiting for 91006 with which they would return to BN |
 |
The old and the new................ |
 |
............and the two locos together before they went their separate ways |
 |
With Lab 6 and TC10
in the formation 91001 propels its test train back to BN and is pictured
near Gamston, south of Retford on 16th June 1988 Frankie Leela |
 |
91001 stabled in Palace Gates
sidings behind Bounds Green with a test train in 1988. Surrogate DVT 43014
was marshalled at the rear sandwiching Lab 6 'Prometheus', TC4 and TC10 in
the first trials of TDM Andrew Whitehead |
 |
The other end of the train Andrew Whitehead |
 |
Yet another end of film shot
shows 91001 on a test train with TC10 behind the loco in Platform 1 at Kings Cross For more details of the various test cars which have been used by the DM&EE over the years look here |
 |
Pictured inside the depot at Bounds Green is an unidentified class 91 with a rake of Mk3 coaches and surrogate DVT (HST power car) |
 |
DVT 43067 on the stops at KX on
22nd June 1989 Treflyn Lloyd Roberts (Flickr) |
 |
91009 heading for BN on 5th
August 1989 and pictured north of Grantham dragging the Mk3 sleepers blunt
end first.
Craig Adamson |
 |
An unknown member of the class
pictured at Crewe en route to BN Dave Bower |
 |
91003 pictured at Bounds Green in 1989 |