If you read the report, it states that NS requires a train that gets a warm bearing alarm to start slowing, but not stopping until the train has cleared the detector. Our instructions are about the same. Using air brakes instead of dynamics could possibly cause a false reading on another car.
Our detectors, and others that I’ve heard over the years, initially don’t give what the defect is or it’s location. They only do so once has cleared the detector or the train has stopped on the detector. Stopping movement on the detector fools it into thinking the train has cleared it. Then the detector announces type of defect and location(s) in the train.
Most of the time, a detector that checks for hot bearings also checks for other types of defects such as dragging equipment, etc. That’s part of the reason a train is allowed to clear the detector. Our dragging equipment only detectors do require an immediate stop if an alarm is given, but doesn’t give location until stopped. Knowing where each kind of detector is located is part of knowing one’s territory.
I don’t agree with not using air brakes to stop the train after receiving an alarm. The admonishment is to use good train handling procedures. I understand the argument, but anything that changes the train dynamic quickly or harshly would cause the burned off wheelset to come out of alignment and cause the train to derail. Excessive dynamics too quickly will increase buff forces. That could "
A critical alarm requires stopping as soon as it is received. Even if the train is still on the detector. Non-critical alarms you clear the detector, as the detector won’t even tell you specifics until you do.
Thanks Reading467 for that information. I downloaded the 10-page report from the NTSB as shown below. Most of the report is unclear to me as to how it affected the outcome at East Palestine. Do have any thoughts or conclusions in that regard?
The report contains 5 pages of technical graphs. Most interesting to me is page 3 of 10; D. FIGURES AND TABULAR DATA; second paragraph. That paragraph is as follows:
Euclid, the emergency occurred due to the derailment. The thing you want from the event-recorder data in the docket, not the report is the rate of change of the throttle control going into full dynamic.
While this is not a hot box induced derailment - it is enlightning as to some of the dynamics that happen when cars hit the ground - for whatever the reason from a train moving at track speed.
I think what I posted above was what you are looking for. It was not from the big final report. It was from a docket list of subjects. I made this google search:
ntsb final report docket east palestine derailment 2023
Euclid, I printed the Locomotive Event Recorders Specialist’s Factual Report in an attempt to compare the lead loco (NS 4178) with the DPU (4412) parameters during the timeframe starting at 2042 hrs, roughly 12 minutes before the emergency brake application.
The engineer starting using the dynamics on the lead and 2nd unit (NS 4224) just before 2050 hours. The DPU’s throttle was in notch 8 until 2051:40, returning to idle at 2052:10 (the 10 seconds is an approvimate reading from Figure 4. According to the Operations Group Factual Report, the crew received the HB Warning at 2053:00, based on recordings taken from inside the cab of 4178. The head end DB was in notch 2. The DPU was at idle.
The engineer notched the head End DB to 5 and the DPU was also in DB 5 when the emergency application was initiated at 2054:24.
I believe the answer to your initial question of where the pileup started is in the Track Factual Report, section 3.1.: “Additional wheel flange derailment markings were observed in the gauge of the track starting about 120 feet west of Pleasant Drive Railroad Crossing at milepost PC 49.2. These derailment markings were observed to the inside gauge portion of the track and run parallel with the north running rail and extend eastward to where the north derailed wheel strikes the Pleasant Drive Railroad Crossing (Note 6).”
So, that’s the apparent cause of the pile-up: the derailed north wheel of axle L1 of Covered Hopper GPLX 75465 hitting the grade crossing structure after the failed bearing on the other (south) end of axle L1 burned off, thereby separating the train line and causing an emergenecy air brake application.
I admit, I don’t know NS procedures, just ours. Nor do I know what alarms might be given. We only have an alarm tone with the words, “defect detected.” Until either clear of a detector or stopped, there is no other info given. If no specific info is given, and it happens, then the entire train on both sides must be inspected.
Again for us, an immediate stop is only required for a defect tone given by a detector that only checks for dragging equipment. We have been having more dragging equipment only detectors beeing put in service, usually at wayside signals, because of the use of concrete ties. Drag a wheel over one and the tie is considered defective.