Do not be mislead by the statements or silence of government authorities.
NTSB reports “When train 32N passed the next HBD, at [Salem] MP 69.01, the bearing’s recorded temperature was 103°F above ambient.”
Sudden burn-off of roller bearings is a well-known phenomenon. Taken at face value, the 103°F statement is plausible and seems to exonerate NS — the bad bearing was still well below the generally accepted alarm threshold of 190-200°F as it passed the Salem HBD. A roller bearing can go from good-to-bad in just 5-10 miles.
The 2/23/23 NTSB report acknowledges surveillance camera images from 3760 Boardman St. in New Waterford, about 4.5 miles west of the point of derailment. But the report omits any mention of the Fresh Mark and Butech Bliss videos at Salem.
Both cameras in Salem clearly show the failing, incandescent bearing was 800-1200°F, far above NS’ 170°F alarm threshold as it passed the Salem HBD, 20 miles and 24 minutes west of the derailment site. Like the Zapruder Film, the Fresh Mark color image is particularly helpful in understanding the evolution of this accident.
What NTSB can/should immediately state is that the Salem HBD failed to produce an alarm message for the failing bearing. The Fresh Mark image proves the failing bearing was detectable at Salem. Had the Salem HBD functioned as intended, the train would have safely stopped at least 18-19 miles west of East Palestine.
Going forward, the sole focus of investigation should be on whether or not 1) somebody deliberately mis-adjusted the Salem HBD calibration or otherwise disabled the system to reduce false stops, or 2) the HBD equipment at this location is unsuitable for its intended purpose due to weather, truck design, track condition, etc.