Hi-Speed Bogie Covered Wagons --- Designed in 2001, variant of BCNA these wagons are 8-Wheeler type, mounted on cast steel CASNUB 22 HS bogie for increased speed, 1000 mm thread diameter, 22.9 T axle load wheel sets, cartridge type roller bearings with adaptors and single pipe graduated release air-brake system. These wagons have 2 doors on each side, suitable for transportation of all classes of goods like food grains, bagged cement etc. requiring protection from weather and natural hazards. Speed 100/100 kmph. Capacity - 56.68 Tonnes. Type - BCNAHS.

Single Pipe Graduated Release Air Brake System - Some of the Air Brake goods stock on IR is fitted with this kind of braking system. In single pipe, brake pipes of all wagons are connected. Also all the cut off angle cocks are kept open except the front cut off angle cocks of break pipe of leading loco and rear end cut off angle cock of break pipe of last vehicle. Isolating cocks on all wagons are also kept in open condition. Auxiliary reservoir is charged through distributor valve at 5.0 kg/cm2.

For application of brakes, the pressure in brake pipe has to be dropped. This is done by venting air from driver's brake valve. Reduction in brake pipe pressure positions the distributor valve in such a way that the control reservoir gets disconnected from brake pipe and auxiliary reservoir gets connected to brake cylinder. This results in increase in air pressure in brake cylinder resulting in application of brakes. The magnitude of braking force is proportional to reduction in brake pipe pressure.

For releasing brakes, the brake pipe is again charged to 5 kg/cm2 pressure by compressor through driver's brake valve. This action positions distributor valve in such a way that auxiliary reservoir gets isolated from brake cylinder and brake cylinder is vented to atmosphere through distributor valve and thus brakes are released