by the Waratah Model Railway Company. European modellers tend to use scale hook and chain couplings. In British 00 scale (similar to H0 scale) models the 'tension lock' coupler developed by Tri-ang is standard. This is similar in operation to the meatchopper type of coupling. Remote uncoupling is possible by using a sprung ramp between the rails. The design of the hooks is such that the couplings will not uncouple when under tension (instead depressing the ramp). When the train is pushed over the ramp, it will lift the coupling hooks as the train passes over. By halting the train over the ramp, it is split at this point. While it works well, it is often seen as ugly and obtrusive (although smaller designs are available, these are not always fully compatible with other models) and many British modellers prefer to retrofit either Kadee types or working hook and chain couplings. A recent development is an interchangeable coupling which plugs into a standardised socket, known as NEM 362 and which can be easily unplugged as required. This allows the modeller to easily standardise on whatever coupling is desired, without individual manufacturers needing to change their coupling type. In 7 mm scale, scale working Norwegian couplings are now being manufactured by Zamzoodled in the UK. A comparison of coupler types was published in "An introduction to Couplers". Accidents Different kinds of coupling have different accident rates. The Murulla rail accident of 1926 involved the breakage of a "drawhook" leading to a runaway and then a collision. Drawhooks imply "buffers and chain couplers". Round Oak rail accident – 1858 – coupling broke and the rear of train rolled back. See also Buckeye Steel Castings Drawbar Gangway connection Gender of connectors and fasteners Jane's World Railways, lists the coupler(s) used on any railway system Railway coupling by country Railway coupling conversion Slack action Three-point hitch Notes References Sources Norfolk & Western Railway Co. v. Hiles (95-6), 516 U.S. 400 (1996) (U.S. Supreme Court decision by Justice Clarence Thomas) Eli Janney — The Janney Coupler (based on above case) Dellner Couplers AB — Automatic and Semi-Permanent Couplers Vancouver SkyTrain Light Rail Network, Canada (these two for Dellner data) JANE'S WORLD RAILWAYS How couplings work Further reading External links FREIGHT VEHICLE COUPLERS AND DRAFT GEAR Adapter piece between Janney coupler and SA3 coupler Locomotive parts Couplers