a few days ago I was at a crossing as a NS train passed there was one car in the middle of train, i am thinking a covered hopper, that caught my attention. What caught my eye was a white hose running along the length of the car attached (tied off) in numerous places. It was connected to the air hoses of the car in front of & behind it. Is this temporary means of by-passing a car that might have a leak or bad piping and keeping the rest of the air system intact?
That’s exactly what it was - a way to bypass a car with defective brakes long enough to get it to a place where it can be repaired. There will be rules governing when this can be done and where in the train the car can be. You don’t see bypass hoses much because there are other ways of disabling defective brakes on a car (branch pipe cut-out, truck cut-out) that will allow the car to remain in the train without a bypass hose. A bypass hose means there was probably something dreadfully wrong with the brake pipe on that car.
It is also termed as a ‘wrap around’ hose. It is used when a car’s own brake trainline is broken and won’t hold air. The car is now moving without air brakes - the car can not be the last car in the train. Line of road shop trucks may not have necessary equipment and/or supplies to repair the defect in the field and will thus attach the wrap around hose so the car can be moved to a proper shop track for repair.
I wonder about this. If I recall correctly, the Power Brake Law even as amended doesn’t say all cars have to be actually braked in a particular train (and of course during the long transition era many cars were only given pass-through hoses for compatibility). At least one of the systems of PTC has the explicit capability of isolating the braking on a car that ‘fails’ testing without breaking the consist – this resulting in a change in the proportioning algorithms to compensate for the ‘lost’ braking power.
Professional railroaders here will know, and I hope will recount, precisely what their railroads require in handling a car that is ‘bypassed’ in this fashion.
I once had a unit sulphur train in winter that had more than 10 cars with run-around hoses, Sultran’s old steel fleet was notorious for air leakage as the sulphur dust would get into every possible place and cause corrosion.
The run-around hose is a means of last resort, and is not carried on locomotives. They are placed and removed by mechanical personnel. We (CN in Canada) don’t have any specific rules or limitations on how far such a car can be moved, they are treated just like any other car with inoperative air brakes.
In Canada the last three cars in a train must have operative air brakes, and no more than two consecutive cars can have inoperative air brakes at any other location in the train. This is to ensure that the tail end will stop itself in the (extremely unlikely) case of a train separation there, and to ensure proper propagation of an emergency brake application.
I did indeed. You can see I didn’t get enough coffee this morning and read too much of the Wrong Paradigm thread.[;)]
In my opinion this is much more a matter of observing ‘craft lines’ than any particular difficulty either in stowing a hose kit on a locomotive or having one crewman quickly and effectively rig it. The entire shebang, including the securing ties, weighs less than 20 pounds! And it rolls up on a reel with a handle, secured by bungee hooks.
I would have to wonder how long the train had been sitting before the truck roll arrived (and possibly how much other traffic was affected by the stop). Surely if a train crew can change a hose, they can be permitted to do this.
(Yeah, yeah, yeah, I know it would be a slippery slope and the carmen’s union would get out their RPGs for the next time they see me… but it would sure beat the time and expense. What I’d gently suggest is that the train crew be given optional body-cam equipment and a carman be connected via ‘telepresence’ – at a minimum plus six-minute increments – to satisfy the union concern while car work is being done.)
Although when you dial in the PTC, you do put in the number of operative brakes. And one road we run on, if there is more than x% inoperative, you cut out the PTC system.
Yes, but the PTC system (to my knowledge) isn’t currently programmed to interrogate an ECP system and automatically isolate deflicted brakes on its way to determining when it ‘can’t trust itself’ – does it have to be disabled by prompt above a certain number of inoperative brakes, or does it automatically cut itself out based on the consist parameters plus what you enter?
I would argue that it would be potentially dangerous both to rely on self-reporting and to be blind to mistakes in actual state of the braking power; it seems to me that in the second Duffy’s Curve wreck PTC would just as blithely started down the hill into much the same disaster.
You either have to self-report, it it has to be able to pull updated consist data (which is self reported by someone else). There is no magical way for PTC to count its cars or brakes.
There are a surprising number of us who possess very little mechanical aptitude.
I recall someone once attempting to move a defective car by chaining it to the operating lever on the next car. All it did was rip the lever off.
Guys couple cars together without first checking that the drawbars are lined up, or do not notice that the air hose is hanging up on the drawbar, so the gladhand gets crunched when the coupling is made.
Others try to put an F knuckle into an E coupler, and fight with it for an hour wondering why it won’t fit.
After 50+ years with CSX and its predecessors - I am not aware of ‘wrap around’ air hoses being carried on locomotives. They get applied by the Car Department when repairs cannot be made in the field.
