In looking at the transit chart for the derailment itself I found much of what I expected. Such tragic events typically include involvement of the 8th house and this was no exception. In this case it was Jupiter, ruler of the Ascendant, at the eye with Pluto in the 2nd house and the Moon in Pisces in the 3rd house of local travel at the base.  Pluto rules death and the Moon in this chart rules the 8th house of death. 

Mercury, natural ruler of motion and travel, was squaring the Moon as well as Neptune, suggesting confusion on the part of the engineer given that the train was moving much to quickly for that part of the route where the train's speed should have been reduced by half.  The engineer is represented by the 6th house of workers which is ruled by Venus who is trining Neptune, planet of confusion and deception.

Both Jupiter and Pluto are part of an aspect pattern I refer to as a Course Adjustment Loop which has been in place for a while now and will continue to be.  I typically interpret this pattern to indicate a crisis which brings about a change of direction which in this case unfortunately was literal and took the train off the tracks.  Uranus in Aries in the chart's 4th house is the third member of that loop, bringing him into the picture.  He's connected to Pluto, natural ruler of revolutionaries and political extremists, by a square and Jupiter by a trine.  This is a rather ominous combination.  Uranus is the planet of surprises, upsets, disturbances and unexpected events who was residing at the time in the 4th house of endings and new beginnings.  Uranus is the modern ruler of Aquarius and thus ruler of the 3rd house of local travel which would apply to a commuter train.  While Jupiter is often considered lucky, this is another case that shows that is often untrue.  Jupiter is mostly neutral as the higher octave of Mercury and simply inflates and increases what he touches with the easy energy flow of a trine not always delivering favorable circumstances.  This loop thus implies an attack by extremists with excessive, transformational/deadly results.

Mars had just entered Gemini from which he's opposing Saturn, another malefic planet, residing in the 12th house which includes hidden enemies and self-undoing.  Mars is also the traditional ruler of the 12th with it's Scorpio cusp.  Saturn rules the 2nd of possessions and substance and is the traditional ruler of the 3rd which includes local travel.  This combined with Mars' placement in the 6th house of work suggests an attack against a commuter train with its passengers in most cases returning home from work.  The asteroid Chiron, the "wounded healer," in the 3rd house of local travel, also fits the situation of injuries during a commute.

This chart is so "textbook" it doesn't deserve much more commentary.  It's interesting that the ascendant at 9:00 Sagittarius forms another aspect pattern known as a Triangle of Potential with the Lunar Nodes while Neptune, modern ruler of the 4th house of endings, is tickling the South Node.  The Nodes tend to bring important events that lead to a new direction. 

UPDATE May 17, 2015:  News reports are now claiming that the train may have been hit by a projectile prior to the crash, distracting or even injuring the engineer.  He was relatively new to that route, having been on it for only three weeks.  This projectile issue is rather interesting given the fact that two other trains where hit in a similar fashion at approximately the same time.  Hidden enemies are included in the 12th house which has a Scorpio cusp traditionally ruled by Mars.  Saturn is resident in the 12th and rules the 2nd house which in mundane astrology includes resources in general.  Saturn is also the traditional ruler of Aquarius, the 3rd house cusp, which includes roads and railways.  Mars and Saturn are in opposition, a hard aspect that suggests aggression for an unknown enemy directed at the train system.  Mars in the 6th house of workers fits the engineer being attacked at the personal level since the projectile apparently came through the windshield.  The Sun rules the 9th house which includes the media as well as other cultures.  One aspect involving the Sun is a separating sextile with Chiron, implying the opportunity to bring injury.  If you look a bit closer, however, you can see that the Sun is forming a T-square with the cusps of the 3rd house of local travel and 9th of other cultures which suggests, albeit subtly, the possibility of terrorism. 

The National Transportation Safety Board (NTSB), the agency that investigates all transportation related accidents, has asked the FBI to assist, specifically due to the technology they can offer the investigation.  Or so they say.  Time will tell.  Perhaps.  The public, represented by the 10th house which just happens to be ruled by Mercury, may not ever know because that square between Mercury and Neptune suggests deception.  Thus, there's a high probability that all the facts in this situation may not ever be known or at least disclosed to the public.

CBS Philly News has the details of the accident and follow-up articles which is where I obtained the information for this astroblog with follow-up information from network news channels, which I don't always believe, but what they say is interesting to say the least.