Tom Everitt
- Feb 23, 2023
- 6 min read

REVIEW - Revolution Trains IIA-D Drax biomass hopper wagons

There is no denying that the IIA-D Drax biomass bogie hoppers are impressive wagons. Volumetrically the largest wagons ever to run on British rails on introduction, N Gauge modellers can now replicate the impressive rakes they form thanks to Revolution Trains and Rails of Sheffield.

The Prototype

First opened in 1974 as a coal fired power station, Drax first tested co-firing biomass in the summer of 2004, becoming the first power station in the UK to be fuelled by wood. The station burns a large range of biomass comprised mostly of wood pellets, sunflower pellets, olive, peanut shell husk and rape meal. The majority comes from overseas through ports at Immingham, Hull, Redcar and Liverpool.

To deliver roughly 20,000 tonnes of wood pellets to the power station every day Drax would need an entirely new railway wagon. To prevent the biomass pellets from exposure to the elements the wagons feature a pneumatically operated roof for each wagon providing easy access for loading, but suitable protection for the pellets when in transit. A similar system fitted to the underside of each wagon makes for simple and easy unloading.

When the wagons arrive at the power station, automated doors on the underside open in stages as they pass through the biomass unloading area. This releases the pellets into a sorter that delivers them into storage, ready to be used for power generation. With this system in place, each train can unload in under 40 minutes.

To get a similar efficiency out of the compressed wood pellet loads as previously obtained with coal, the new wagons needed to be high volume. This was achieved by adding additional hoppers at each end of the wagon over the brake equipment and pushing the size of the body to the maximum the UK loading gage would allow. The result is a wagon with 116m3 capacity, almost a 30% increase in volume compared to the coal wagons.

GBRf 60026 'Helvellyn' at Colton working 6N45 Drax to Tyne dock biomass empties on 09/06/2020 © Mr P

200 wagons were ordered from WH Davis in 2013 with the first entering service the same year on flows from the four ports to Drax. The wagons were originally outshopped in the eye-catching Drax power livery, some since receiving 'Northern Powerhouse' branding and additional images. A third livery has recently been applied to some wagons featuring an overall blue scheme with large imagery and 'drax' logos.

Since introduction, common motive power has been provided by classes 60 and 66 in various liveries including EWS, GBRf and Colas. The Class 70 has also made a handful of appearances under trial.

The Model

Announced in December 2020 and now available exclusively from Rails of Sheffield, the Revolution Trains N Gauge IIA-D is now available and is every bit as impressive as the real wagons, fully capturing the huge size and bulk of the prototypes.

The body of the wagons are a one piece moulding and feature fine raised lines that represent the welded construction of the prototypes. The hopper covers are moulded as part of the body, and include some very nice fine detailing in the line of hinges along each side.

The openings in the bodyside between the outer and inner hoppers which allow access to the brake equipment are present, along with a representation of the pipework and cylinders that make up the brake system. There is some fine detailing here which is not immediately visible to the eye given the tight space it's contained in but kudos to Revolution for including it! Overall the model captures the bulky appearance of these huge wagons to a tee, and there is no doubt that even a short rake makes for an impressive sight.

The wagon ends include separately fitted detailing for the buffers, roof door actuators and at one end the hopper doors control box with the associated wiring & pipework moulded as part of the body. The various items of pipework found on the buffer beams are supplied as user fitted items.

The lower section of the body features some find moulded brake system pipework and supporting brackets, and as per the prototype some of this is represented as being slightly slack and not completely straight along the length of the wagon. The hopper discharge chutes are neatly moulded with doors and representation of the actuating mechanism being a separately fitted part. Some of these on the models reviewed had a slight upward bow, and we are not sure if it is an issue with the doors not being fitted correctly or the moulding itself, however this was the only minor niggle with the moulding we identified.

The wagons do not feature a kinematic close coupling mechanism, and given the presence of the end discharge chutes it's difficult to see how fitting one would have been achieved anyway. Revolution have cunningly hidden a pivoted NEM pocket within the two end chutes which allows for some sideways movement and those without sharp curves on their layout should be able to swap the supplied long shank couplers for short versions to achieve closer coupling.

The wagons run on an excellent representation of the LN25 bogie found under the prototype, and these are exceptionally free rolling which will help ensure locomotives are able to haul rakes of prototypical length, often in excess of 22 wagons. The relatively light weight of the models will also help there, with them coming in at 23g. Fine, separately fitted handbrake wheels finish off the detailing.

Livery

Perhaps the most striking feature of these models is the livery. The vinyls of the prototypes feature several elements that are not easy to reproduce in model form, let alone in N Gauge, but Revolution have really excelled themselves when it comes to replicating the fading colours and photographic elements in this small scale.

The most impressive versions are those wearing the latest drax 'renewable pioneers' livery of overall dark blue with large photographic elements and smaller green squares. There are 4 different pictures in use featuring different images associated with drax power station and the images are remarkably sharp and clear.

In model form, the liveries have been replicated superbly by use of waterslide transfer, so almost model imitating the vinyl application used in real life! There was some speculation that the livery was applied using UV printing, but Revolution have confirmed to NGN that it is in fact waterslide decals. This method has allowed for the imagery to be reproduced in very high resolution, making the quality of the photo elements the best we have seen in N Gauge to date.

The alignment of the decals is generally excellent, although on the 'Northern Powerhouse' versions reviewed here there was some slight misalignment at one end, resulting in the decal wrapping around over the bodysides and a slight gap around the cut out for the bodyside brake equipment access. This wasn't noticed until reviewing the hi-res photos for the review, so we consider this to be a minor niggle. The application of the 'Renewable Pioneers' livery was excellent on all the wagons purchased in this scheme.

Thanks to the high resolution of the decal artwork, all but the smallest text is legible across the many data panels found on the wagons. The colours appear to be an excellent match for those of the prototype with the various different blues and greens of all livery variations appearing spot on.

Summary

We really can't commend Revolution Trains enough for achieving the standard of finish they have with these wagons, given the highly complex nature of the prototype livery, and they certainly make for some of the most eye catching and imposing model wagons yet produced in N Gauge with excellent detailing and running adding to the overall high quality.

Even though the real wagons are somewhat geographically limited, they will make for a very impressive rake on any layout, particularly if you have the space for one of prototypical length.

Availability

The IIA-D is now available exclusively from Rails of Sheffield, with the following twin packs available for purchase:

N-IIAD-221A