European Railroad Discussion > French TGV crash: excess speed, possible PTC failure?

On the Passenger Board:

http://www.trainorders.com/discussion/read.php?4,3892971

Here's my takeaway from the 26 page preliminary report:

1.  There seems to have been no indication of materiel failure, including whatever "PTC" as used elsewhere on TO Forum and Trains magazine, means.  [  It is possible that the TVM 430 system was turned off, but I've seen nothing to indicate that, as there was no reason to turn it off and, indeed, it is highly likely that it was kept on;  only the COVIT overlaid enforcement would have had to have been disabled, because of the +10% speed requirement.  I believe that also disables any KVB speed commands.]

2.  There were seven personnel in the cab;  the four nominally authorized were,
    - two engineers
    - a "Senior Traction Inspector" -- I have very freely translated that title
    - and, most importantly, a pilot [ same meaning as in North America ]:  One who was familiar with the trackage in question, to provide specific guidance on operation

3.  Full service rather than Emergency braking was used;  see p. 13 for the cab controls' position as found.  Note also the deceleration curve for the SNCF provided "Speed levels for Test program", both actual and desired.  It is also of interest in that latter document that while "testing speed" [ my choice of words ] is shown to drop from 360 to 330, there is no farther incremental drop until it goes right to 176, just 5 km later.

4.  Speculation on my part:  Had it not been for the bridge structure, it seems possible the train would have derailed but might not have overturned.

Other inputs, preferably informed, welcomed.

SZ
 

But, wasn't the PTC turned off for testing? All reports I've seeen point to that direction. I doubt TVM430 will be able to run +10 the maximum production speed when it is on. Or is it? Anyways the reports from U.S. are on the derailing speed 241 km/h in line with the European sources.

Somehow I find it amusing that Trains magazine of all the media is used as a reference on the Passenger Trains board ;)   I'm disappointed that the first hand information (lots of it available for this unfortunate incident)  from French sources was overlooked. 

Still, as documented earlier, it is very strange that so many people were aboard on this ride known to have its dangers: http://www.trainorders.com/discussion/read.php?17,3889121
 

As reported at Trainnews the French say the train operator held speed too long and then used excessive braking at the last minute.  Reminds me of the NE corridor incident.

As well as the Spanish incident two years ago or Norwegian incident three years ago. Norwegian unit was test train just like the #744 here.

espee99 Wrote:
-------------------------------------------------------
> As reported at Trainnews the French say the train
> operator held speed too long and then used
> excessive braking at the last minute.  Reminds me
> of the NE corridor incident.

Here is a picture of TGV-Dasye unit 744 back in 2012, when it was serving long distance traffic between Nice and Paris.

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