Northeast Regional 188 - Accident In Philadelphia

FRA just issued the following Safety Advisory:

"Operational and signal modifications for compliance with maximum authorized passenger train speeds and other speed restrictions"
http://www.fra.dot.gov/eLib/Details/L16416
FRA - 6/9/15

BenH wrote:FRA just issued the following Safety Advisory:

"Operational and signal modifications for compliance with maximum authorized passenger train speeds and other speed restrictions"
http://www.fra.dot.gov/eLib/Details/L16416
FRA - 6/9/15

A lot of self serving political hot air.

Tommy Meehan wrote:

Fishrrman wrote:....
So.... he does the only thing he can do -- he dumps it.
...

Some veteran railroaders believe the only chance he had of getting around that curve was by not dumping it.

Interesting... I'm involved in auto racing, so am aware that at times when you enter a curve at too high a speed you do NOT want to touch the brakes. So, please explain.

I'm going to go COMPLETELY out on a limb here, but my guess is because dumping air travels at the speed of sound, it means the front of the train starts to brake first, which means you get run-in which means the momentum of the back end is now pushing your front end in a tangent to the curve it's trying to negotiate.

That is part of it ... there's also the shock of the slack running in ...

When it slams to the endstop, it's a ridiculously massive collision.]

Ever heard a train slowing down? BAM! BAM! BAM! BAM! BAM! ...

Now imagine that force banging a car @ 106mph. In a curve. It could literally push you right over the top of the rail.

At least that would be my theory supporting your theory ...

Doesn't Amtrak use electrical brake propagation, as opposed to pneumatic propagation that is used in freight cars. With electrical brake propagation there would not be the 'severe' slack run in that there would be pneumatic brake propagation. With electrical brake propagation the brakes would begin to apply on all cars at the same time with the only differences being whatever differences there were in the adjustments of the brake actuating mechanisms.

scopelliti wrote:

Tommy Meehan wrote:

Fishrrman wrote:....
So.... he does the only thing he can do -- he dumps it.
...

Some veteran railroaders believe the only chance he had of getting around that curve was by not dumping it.

Interesting... I'm involved in auto racing, so am aware that at times when you enter a curve at too high a speed you do NOT want to touch the brakes. So, please explain.

Braking a car or motorbike while cornering increases the force on the tires , which if you are racing will be near their maximum adhesion limit anyway, so causing them to lose grip and slide.
Probably a different cause and effect from a train braking in a corner, which I imagine has something to do with the slack / pushing action mentioned already.

mmi16 wrote:Doesn't Amtrak use electrical brake propagation, as opposed to pneumatic propagation that is used in freight cars. With electrical brake propagation there would not be the 'severe' slack run in that there would be pneumatic brake propagation. With electrical brake propagation the brakes would begin to apply on all cars at the same time with the only differences being whatever differences there were in the adjustments of the brake actuating mechanisms.

Nope, it's pneumatic for passenger trains as well Just a lot faster, and Amtrak, along with most passenger operations, use graduated release on passenger cars as well. Passenger cars just do not have as much slack as a freight train, but still, when there IS run in (and I've felt enough of it on mixed NJT trains), it is noticeable...

David Benton wrote: Braking a car or motorbike while cornering increases the force on the tires , which if you are racing will be near their maximum adhesion limit anyway, so causing them to lose grip and slide.
Probably a different cause and effect from a train braking in a corner, which I imagine has something to do with the slack / pushing action mentioned already.

On a car braking in a corner shifts weight forward, so the front tires have more grip and the rear tires have less grip. Do this at the limit and you'll spin. Try it in an older Porsche 911 and you'll really spin (TTO - trailing throttle oversteer)!

Back to trains... I can see where the braking forces could cause derailments. Interesting... but would an engineer think that fast?

I'm more used to riding motorbikes fast, where you have seperate front and back brakes. Regardless, the issue with road vehicles is loss of adhesion, which I don't think is the issue with a train .

n2cbo wrote above:
[[ 1.) Two other engineers (In the US we call them engineers, NOT enginemen ]]

They were known as "enginemen" for years on the Penn Central...

mmi16 wrote above:
[[ Doesn't Amtrak use electrical brake propagation, as opposed to pneumatic propagation that is used in freight cars. ]]

No (unless they've changed something on the Amfleet equipment since 2012).
The "EP brake" (electro-pneumatic brake, which used electronic controls in addition to changes in brake pipe pressure) was tried when the Amfleet equipment was first introduced in the 1970's, and disconnected not long afterwards. Hasn't been re-tried since. Amfleet and conventional trains are "air only". The Acela trains -do- have electrically-assisted brakes.

Re the comments above suggesting how "he could have made it if he hadn't dumped it..."

Just had lunch today with another retired engineman who actually hired out back in 1969 on the PC, and we talked about this. He mentioned that, too.

I don't think there's any way to know that for certain, but it's hard to believe that trying to negotiate a 50mph curve at 106+/- was going to end up with the train still on the rails. 80-85mph, well, maybe. But more than twice the speed? Forgeddaboutit!

Fishrrman wrote:Re the comments above suggesting how "he could have made it if he hadn't dumped it..."

Just had lunch today with another retired engineman who actually hired out back in 1969 on the PC, and we talked about this. He mentioned that, too.

I don't think there's any way to know that for certain, but it's hard to believe that trying to negotiate a 50mph curve at 106+/- was going to end up with the train still on the rails. 80-85mph, well, maybe. But more than twice the speed? Forgeddaboutit!

Ever hear of "The Flying Rail Train?"

So the story goes, in 1975, a loaded Penn Central welded rail train departed Pittsburgh eastbound. Many of the brakes on the cars, along with the locomotive dynamics were reported inoperative. As the train exited the Gallitzin tunnels on Track 1 (the Slide), the engineer knew already he was losing control. The conductor cut off the caboose, and the train went careening the entire way down. Depending on whose report you got, it went around Horse Shoe Curve at anywhere from 55 to 80mph (normally 25mph). The train finally came to a stop a few miles east of Altoona. It is said that the fact it was loaded is what saved it... that ribbon rail created a low center of gravity.

The full story was in a 1985 edition of Trains magazine covering Horse Shoe Curve, IIRC.

IIRC round 1993 or 94 ? a Metroliner went around the eastbound curve at Elizabeth NJ at 100 plus MPH. The motor and the first cars pushed the rail out a few inches but did not derail. I recall hearing the conductor dumped the train and hauled it down from 120 mph. The wheels were destroyed but the pandrol clips and concrete ties apparently held the line. The incident did occur but its all second hand so don't hold me to the details perhaps some one here can fill in the blanks. Scuttlebut was the engineer had been running MARC trains between Balto and D.C. for 18 months had not been past Baltimore or Elkton. Federal law requires an engineer to operate or ride over a territory in order to stay qualified on physical characteristic's within a 12 month period. If he does not, and exceeds the specified 12 month time limit his current qualifications "run out." He must go to the rules examiner, ride over the specific territory for a set time, and then pass a physical characteristics test. Once he passes, his qualifications are legally renewed and only then may he operate a train over that territory.

Again what I heard, the engineer signed up for his regular D.C.- Baltimore MARC trip and the road foreman asked if he would run the Met up to New York, as they had no engineer for it, and he said yes even though his qualifications had run out north of Elkton MD by 6 months. Apparently he forgot about the Elizabeth curve speed restriction and was barreling into it at 120mph. The conductor realized this and dumped the air and slowed it enough, preventing a bad wreck. The engineer was canned over it. Regarding No.188 I highly doubt the Shore curve could handle anything over 85 mph without lifting a wheel off or spreading the rail and initiating a major derailment.

another piece of puzzle , no phone use. http://www.ntsb.gov/news/press-releases ... 50610.aspx" onclick="window.open(this.href);return false;

DutchRailnut wrote:another piece of puzzle , no phone use. http://www.ntsb.gov/news/press-releases ... 50610.aspx" onclick="window.open(this.href);return false;

and a news report issued within the last hour or two: http://www.nj.com/news/index.ssf/2015/0 ... cart_river