Palmetto - Train 89 Incident

A blocking device is a tool that prevents trains from entering a certain track, on old CTC machines it was a clip that blocked the button to give a signal and route.
these days, its a computer block that will prevent entry to a block by train.

edit - didn't see Dutch's response which is more succinct and to the point

Merged into Palmetto accident thread - I don't think we really need a separate topic that's going to just point back to the incident in question.

CPSK wrote:Hi;
With reference to yesterday's Amtrak accident in Chester PA, I am interested to know whether "blocking devices" were properly applied on the track where the backhoe was working.
While I do understand that this information cannot be known until the investigation is complete, I would like to better understand what blocking devices are, and how they are used, as I often hear the term while monitoring the radio when a "form D" is being issued. Are blocking devices actual hardware that completes the signaling circuit so that no trains will be permitted (block occupied - stop signal) into the affected block, or are they only virtual devices applied by the dispatcher?

Thanks for your help

CP

Gilbert B Norman wrote:This did all that?

Just add track speed to finish the equation.

Interesting;
I would think that having a device that would cause the signal circuit to show a train in the block - such as a jumper wire across the rails - would still be used. But now that I think about it, that would create problems with grade crossings.

CP

To further clarify, modern blocking devices with computer software are a matter of simply clicking to place on a stretch of track and will not allow the dispatcher to throw switches within that section, nor signal into that section. A blocking device doesn't "prevent a train" from entering a block and is in fact sometimes used to move a train into a block (ie: Rule 241 Permission to Pass Stop Signal with NORAC, etc).

In reference the post immediately above, grade crossings are not an issue on the Northeast Corridor except in very limited instances in Connecticut. Crossings can also be removed from service on a track where shunts or shunting equipment are being used. And finally, the shunt does not have to be in the crossing circuit, but anywhere within both the out-of-service limits and the signal block the work is taking place in. If I were a track foreman, I would apply shunts or otherwise afford myself signal protection in the field even if my operating rules didn't specify that I had to.

JimBoylan wrote:I think that the Congress critters promised us that Positive train Control would prevent Roadway Workers and equipment from fouling trains?

I realize you're being sarcastic here, but I don't know that ANYTHING is going to prevent an accident where there's an item that does not touch the tracks that fouls the ROW. I doubt this equipment was OK the track; seems to me much more likely that some part of it was hanging in the way, if you look at the damage.

The same type of comments as last spring.
The NTSB will investigate and scrutinize every aspect of it, then we will eventually
learn the real cause.
Why do we always have to have all the speculation?

Lee

CPSK wrote:Interesting;
I would think that having a device that would cause the signal circuit to show a train in the block - such as a jumper wire across the rails - would still be used. But now that I think about it, that would create problems with grade crossings.

CP

Amtrak uses just such a device, consisting of a metal bar spanning both rails, and bearing an octagonal red sign (like a highway STOP sign) reading BARRICADE. Quite likely barricades were in place on Track 4; however, since the train was properly on Track 3, as pointed out by various people above, shunting the circuit on Track 4 wouldn't have helped. Ironically, Amtrak introduced the barricades some years ago following a collision in that same territory (between HOOK and either BRILL or PHIL, whichever was in service at the time), in which the operator at HOOK forgot to place a blocking device as required, and his relief either didn't know or wasn't told about the M/W crew working on that track, and a northbound Amtrak train hit the equipment at speed.

Engineer has been released from hospital. These ACS64s no doubt have proven themselves to be very safe locomotives.

justalurker66 wrote:

Gilbert B Norman wrote:This did all that?

Just add track speed to finish the equation.

Listed weight for a Case 580 backhoe is 16,589 lbs.

ACeInTheHole wrote:Engineer has been released from hospital. These ACS64s no doubt have proven themselves to be very safe locomotives.

A good point. 2nd crash where the engineer was not seriously injured. Something in this crash management after all.
There was some talk of using drones to survey the way ahead of trains. Years ago , i saw a proposal to have a remote buggy type vehicle travel ahead of the train, by just overthe braking distance. The idea been it would detect objects fouling the track , and allow the train to stop in time.

And then when something fouls the track right after the remote buggy, we'll have "2nd Remote Buggy" to back that one up.

David Benton wrote:Years ago , i saw a proposal to have a remote buggy type vehicle travel ahead of the train, by just overthe braking distance. The idea been it would detect objects fouling the track , and allow the train to stop in time.

That's known as a Pilot Train. A most visible one of such was the three car train that proceeded the 2009 Obama Special from Phila to Wash.

CNN reports "workers on the wrong track":

http://www.cnn.com/2016/04/04/us/amtrak ... index.html" onclick="window.open(this.href);return false;

Fair Use:

Chester, Pennsylvania (CNN) — Strong evidence suggests two Amtrak construction workers killed in a train crash made a "colossal" mistake by being on the wrong line, a source close to the investigation said Monday.

The crash occurred Sunday morning when an Amtrak train carrying 341 people slammed into a backhoe on the track near Philadelphia, killing the two construction workers.

Another 37 people were injured and treated for minor injuries, a Chester city spokeswoman said.

Investigators will try to determine why the construction workers may have been on the wrong line, which was considered "active," the source said....