The C&TS has two train sets, with two systems. The Antonito coaches (built first) still have K triple brakes on them. That is fine for the 1 1/2% ruling grade on the east side of that road. K-triple have three reservoirs to recharge. The engineer, after releasing a set on the brakes is supposed to give the triples at least 45 seconds to recharge. This is harder to do on the 4% where you often have to get on the next set sooner. I found the little reservoirs will recharge property with a minimum of 30 seconds. The 4% does have some stretches where you can let the reservoirs recharge longer, so knowing the road is very important.
The Chama train set (built later) has AB brake valves on the cars. The advantage with AB is that the little reservoirs inside the valve recharge faster than K-triples. However, myself and other engineers like Carlos are more cautous than mainliners, and let the system recharge up to 30 seconds, just to err on ther side of safety. An engineer can "short-cycle" AB and some did. "Short-cycling" is setting and releasing as needed, and not worriying about the AB reservoirs recharging. Once I had a long train that had 4 K-triples and about 12 ABs. Coming up it a flat spot I short-cycled ,knowing that it would be safe. The 4 K-triple cars slapped against the back of the K-36. Why? The brakes in them had not recharged, and were no longer working! However, the ABs were holding fine. When I arrived in Chama, the conductor, Henry Gallegos patted me on the back, telling me that was the "best darn ride" down the hill he ever had!
There are many curve balls taking a train down Cumbres. Long trains handle better than short trains (more brakes). Brake travel is important, as loose brakes make the train harder to handle. Also some cars' brakes would lock up and slide, and the trainmen would inevitably take down the retainers on them, and the train would lose braking (retainers retard the release of the brakes. All cars going down grade from Cumbres to Chama are supposed to have their retainers up in the 10 lb. position). Like Carlos, I would cut out the engine brake and bleed off the tender brake. This is done by cutting out the "mountain cock"(engine brakes)and bleeding off the independent (tender brakes). However, if a train was short and hard to handle, I would hold the tender brake and occaisonally cut the engine brake back in, if for only a short time, to get the train down to a controllable speed.
Both Westinghouse systems are excellent, and if maintained, do what they are supposed to. The AB is a better system in my opinion. Both systems are forgiving, and I know of engineers getting a hold of a train of K-triples even after he "lost" the air. Like many aspects of this dangerous busiess, you will live as long as as an engineer knows what each system is capapble of and maintains a respect for the limitations of any system that is measured and deep.
