A preliminary investigation revealed an area in a curve where the subgrade fill was subsided from the track structure. The investigators found that this fill was subsided for about 26 feet (at a depth of 18 inches) at MP 102.9.
Accident Location:
Alexandria
,
VA
USA
Accident Date:
5/19/2018
Accident ID:
RRD18MR007
Executive Summary
The
information in this report is preliminary and will be either
supplemented or corrected during the course of the investigation.
On May 19, 2018, about 7:02 a.m. eastern
daylight time, southbound CSX Transportation (CSX) freight train X41518
derailed near mile post (MP) 102.9 while traveling on main track one.
The derailment occurred about 500 feet north of two CSX bridges that
cross over Norfolk Southern Railway (NS) tracks. A CSX bridge on main
track one was extensively damaged; a CSX bridge for main tracks two and
three remained in service. Some of the derailed CSX freight cars fouled
the NS tracks that were below the bridge. (See figure 1.)
Figure 1. NTSB drone aerial photograph of damaged bridge and debris.
The train consisted of 3 locomotives and 167
mixed-freight cars (that is, 91 loaded cars and 76 empty cars). The
train was 9,910 feet long with 14,394 trailing tons. None of the
derailed cars were transporting hazardous material. Of the 31 derailed
cars, 25 cars (in positions 42nd through the 66th) derailed at MP 102.9.
An additional 6 cars (in positions 89th through 94th) derailed at MP
103.2. The train crew was uninjured. Damage is estimated to be between
$5 and $7 million.
At the time of the accident, there were low
clouds, wind was from the northeast at 9 mph, 7 miles of visibility with
light rain (approximately 1/10 inch per hour), and the temperature was
58˚F. Prior to the derailment, a severe storm warning for this area had
been in effect until May 19 at 3:00 a.m. Rainfall in the area before
the accident totaled approximately 5 1/2 inches over a 10-day period
that began May 9, 2018.
A preliminary investigation revealed an area
in a curve where the subgrade fill was subsided from the track
structure. The investigators found that this fill was subsided for about
26 feet (at a depth of 18 inches) at MP 102.9. (See figures 2 and 3.)
The NTSB investigators also identified a flange mark traversing over the
top of the rail head in the curve and the at the location of the
subsided subgrade.
Figure 2. Ballast subsided from the outside edge of the crossties.
Figure 3. NTSB aerial drone photograph taken after freight cars were removed from main track one;ballast is subsided from outside edge of crossties.
Investigators accessed the lead locomotive
and downloaded event recorder and video from the forward-facing video
recorder. Based on the preliminary data from the event recorder, the
train speed was about 38 mph at the time of the derailment.
The NTSB formed the following technical investigative working groups:
- Signal Systems
- Track and Engineering
- Mechanical/Equipment
Investigators inspected the track structure,
the signal system, and the mechanical equipment. They are collecting and
examining maintenance records. Investigators interviewed the CSX train
crew and other CSX personnel. An NTSB aerial drone recorded the accident
scene, especially the derailed equipment and the damaged bridge.
Parties to the investigation include the
Federal Railroad Administration, the Virginia State Corporation
Commission, CSX, and the Brotherhood of Maintenance of Way Employes
Division.
Probable Cause
The
information in this report is preliminary and will be either
supplemented or corrected during the course of the investigation.