top of page
  • Writer's pictureTom Everitt

REVIEW - Dapol Foster Yeoman O&K JHA hopper wagons

First announced in September 2021, the Dapol O&K JHA hopper wagons are now arriving with stockists. N Gauge News takes a close up look at these brand new N Gauge models.

Dapol N Gauge JHA

The Prototype
O&K JHA wagon
JHA OK19340 at Westbury waiting to head back to Merehead. © Jo Alder

During the early 1980's, Foster Yeoman were becoming increasingly frustrated with the poor reliability of motive power provided by British Rail to haul their aggregate trains from the Torr Works quarry in Somerset to various destinations in the South of the country. This led to negotiations for access to British Rail metals for their own fleet of locomotives and the eventual order of four new Class 59 diesels designed and produced by the American company General Motors' Electro Motive Division. The new locos were considered revolutionary at the time for being the first privately owned motive power in use on the BR network, as well as being the first American built diesel locos in regular use in the UK. To accompany them, new air braked bogie hopper wagons were also ordered from German manufacturer Orenstein & Koppel.

The order for 100 wagons, designed to be loaded to a maximum weight of 102 tonnes, was placed in 1988 and they were originally coded PHA under TOPS before being changed to JHA in the early 1990's.

The bogie hopper design would offer significantly increased load to train length over the fleet of twin axle PGA wagons then in use. The new wagons would allowed greater volumes of aggregates to be transported to existing terminals where siding lengths were limited or could not be extended. The load is emptied via 3 clamshell doors underneath the wagons, meaning the brake equipment is mounted at each end above the frame and is protected by distinctive sloping panels.

Designed to run in fixed rakes, two variations of wagon were produced. Inner vehicles feature knuckle couplings at each end, whilst outer wagons have a buckeye coupling at one end, and buffers and drawgear at the other. The length of the fixed rakes can vary within the full makeup of the train.

Rakes of JHAs can also be found in the 'Jumbo' aggregate trains run by Mendip Rail from the Southwest to Acton, before they are split and sent onward to various destinations. These can be trains over 40 wagons long, and feature JHA rakes mixed in with other types.

59104 passes through Sonning cutting with 7A09 Merehead – Acton, formed of 44 wagons. The formation shows how the ‘Jumbo’ trains can marshalled, with one loco taking three separate portions to Acton where they are split to go forward to their separate destinations. © Jo Alder

With the entire order delivered by 1989, they entered service in the striking silver and blue Yeoman livery to match the Class 59s. This scheme was unchanged until 1998 when the wagons began to appear in a new variation of the Yeoman livery which they wear to this day. Some minor variations have appeared over the years resulting from repairs, including at least one wagon in all over silver without branding, and as with many modern wagons, they have also seen their fair share of graffiti over the years.

With the merger and pooling of the Yeoman & ARC Class 59 fleets, operation by EWS/DB Cargo and subsequent sale of the locomotives to Freightliner in 2019, the JHAs can be seen behind various sub classes and liveries of Class 59, as well as seeing haulage by classes 37, 47, 58, 56, 60 & 66 over their lifespan, making them versatile wagons for modellers.

© Jo Alder

The Model
Dapol N Gauge JHA

The latest in a series of bogie hopper wagons from Dapol, the JHA follows on from the OO Scale model of the same type, and shares many of the design features from its larger sibling.

First impression on removing the model from the box is wow, heavy! For an N Gauge wagon they are certainly weighty, coming in at 38g each even without a load, so for those hoping to run prototypically long aggregate trains we hope the forthcoming Class 59 models have motors up to the task!

The overall shape of the wagon looks spot on, with the bulky slab sided appearance being well captured. The distinctive three square patches running the length of the sides are also correctly represented as are the body end weld lines . The lower tumblehome is present and the upper stepped changes in body side angle toward the top edges of the hopper are well represented. The recesses for the handbrake wheels are present along with separately fitted wheels, whilst the document storage container is also represented. Lifting points are also separately fitted parts picked out in yellow.

Dapol N Gauge JHA

At each end there is some nice detailing including fine, etched mesh walkways and handrails, plastic moulded ladders and the ridged cover for the brake equipment all represented. The outer wagons also feature buffers, grab rails and coupling hook along with a non functional representation of a tail light.

The construction of the N Gauge models follows the OO version, with the sides and hopper ends/frames and chutes being separate mouldings. This allows for an impressive full depth representation of the interior of the wagon which also includes the cross bracing.

Dapol N Gauge JHA
Dapol N Gauge JHA

The underside of the wagon features representations of the three mechanically operated clamshell doors for unloading, along with some fine detail for the operation/locking mechanism.

Dapol N Gauge JHA

Kinematic close coupling mechanisms are fitted with standard N Gauge NEM pockets. The Inner wagons are only provided with a very neat representation of the buckeye couplings of the prototype. These give excellent close coupling between wagons and look much better than the standard rapido coupler. The outer wagons are the only ones fitted with a rapido at the buffered end.

Dapol N Gauge JHA

A minor niggle with the couplings is that as a result of being on the kinematic mechanism they a mounted lower than they are on the real wagon, but Dapol have included part of the mechanism on the end plate usually found under the coupling on the prototype, placing this above the coupling on the model. The result is this detail fowls the mechanism when it moves to the right, limiting it's range. Whilst this didn't appear to cause any issues when running on the NGN test circuit, it may on tighter radius curves.

Dapol N Gauge JHA

The model rides on a very neat representation of the characteristic O&K bogies which feature good depth of detail, separately fitted brake shoes inline with the wheelsets and with a commendably small gap between bogie and body. It's here however that we encountered a problem.

When running the models around our test oval of Kato Unitrack, it became evident that the wheelsets on the buffer end bogie of the outer wagon were dragging at certain points. The inner wagon ran smoothly until the slightest pressure or extra weight was added and dragging also became visible. Initially suspecting swarf in the pinpoints or miss-aligned brake shoes rubbing against the wheels, on removing the bogies to inspect them it became obvious that there is such a small gap between the top of the wheels and the lower surface of the wagon floor that even the slighted undulation in the track was causing the wheels to rub against the chassis floor.

You can see the scratch marks made by the wheel flanges as a result of this issue in the image below:

Dapol N Gauge JHA

Whilst transiting curves, the outer wheels were also prone to catching the edge of the recess for the coupling mechanism, so those with changes in elevation on their layouts may well have issues due to the restricted ability of the bogie to pivot without catching.

The chassis floor casting could really have done with some recesses to prevent the wheels fowling the underside over less than perfectly flat track, and those confident in doing so may wish to add some themselves to alleviate the issue. An alternative solution my be to add a very thin shim washer between the wagon and the bogie mounted spigot to increase the gap and reduce the risk of catching.

Further examination of the bogies reveals that the wheelsets are mounted slightly lower than they should be, presumably in an attempt to allow scale sized wheels to be fitted without, in theory, fowling the chassis or requiring cut outs in the lower body sides and this means the axle boxes are not inline with the centre of the wheels. This isn't particularly that noticeable in a small scale like N unless viewed directly side on.

With the above in mind, it would be our recommendation that if buying in person from your local model shop you ask them to check the running of the wagons first to check for this issue. If buying online, you may wish to ask the retailer to check for free running before dispatching.


The quality of the finish is excellent, with smoothly applied paint and good colour density. The finer printing is sharp and legible down to everything except the smallest of details.

The models reviewed here represent the second iteration of the Yeoman silver and blue livery and whilst the blue used for the wide band and logo text is a good match for that of the prototype, the grey colour used by Dapol for the base colour doesn't quite match the more silvery colour of the real thing to our eyes. It's not massively far off in appearance, and metallic colours are difficult to accurately represent in smaller scales, but it's distinctly more grey than silver on the model.

Dapol N Gauge JHA

TOPS panels, warning information and operating instructions are all represented and the axle boxes on the bogies are picked out in yellow.

Those wishing to weather their models may wish to keep an eye on Steadfast Models for future graffiti packs specific to these wagons.


These are visually impressive wagons and combined with the excellent standard of finish Dapol have captured the appearance of them extremely well. They will certainly make for an impressive sight when running in long rakes (we envy anyone able to replicate the jumbo trains on their layout!!)

The issue we experienced with the catching wheels makes it difficult for us to recommend these models outright and without reservation, but if you find examples not affected by the problem we encountered then there is no reason not to add them to your N Gauge wagon fleet!

Dapol N Gauge JHA

Dapol have produced 6 running numbers of inner wagon, 3 in original and 3 in later livery variation, and 4 running numbers of outer wagon, 2 in original and 2 in later livery variations.











The RRP is £39.95 for all versions.

The models reviewed here were purchased by the reviewer fro £33.95 from Rails of Sheffield

N Gauge News would like to extend our sincere thanks to Jo Alder for his assistance with the prototype information, photos and formation diagram.



bottom of page