Prototype Railroading Terms - Part 4 - Model Train Help BlogModel Train Help Blog

January 17, 2006

Prototype Railroading Terms – Part 4

This model railroad blog will list various railroading terms five or six at a time over the next few weeks.

Bleeder
This valve bleeds (releases) air from the auxiliary air tank reservoir on a car.

Blended Braking
Uses a mix of service braking and dynamic braking.

Block
A length of track with defined limits on which train movements are governed by block signals, cab signals, or Form D’s.

Blocking Device
A lever, ring, plug, or other control method to restrict the operation of a switch or signal. The abbreviation “BDA” means Blocking Device Applied and “BDR” means Blocking Device Removed.

Blocking of Cars
The assembling of cars in proper groups.

Block Signal
This is a fixed signal which is displayed at the entrance of a block to govern use of that block.
Block System A block (or series of consecutive blocks) within ABS, ACS, CTC, or interlocking limits.