Recent, Important or Popular Topics Related to Analysis of Motor Vehicle Collisions
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They should've sued the French roads authority for an unsafe dangerous road. Those pillars were an accident waiting to happen
Our Response:
In the US many road and vehicle safety items have been implemented as a result of lawsuits.
Also due to the 1960s highway safety act highway safety agencies (NHTSA, FHWA and NTSB) were formed to investigate crashes, find out where and why people are injured and killed on the highways and implement changes to improve vehicle safetyand highway safety.
You will find barriers in front of most bridge supports in the US!
And barriers to try to keep errant vehicles from running off the roads!
In France, it is my understanding that they STILL do not have any type of barrier to prevent an errant vehicle from running into one of those posts?!!
However in the past 23 years i haven't read about any crashes in that location causing more deaths or injuries.
For more information on the history of vehicle and highway safety in the US see
Seriously, which idiot designs tunnel expressways with exposed pillars instead of concrete safety barriers. Idiotic. Poor safety construction standards.
Our Response:
Not sure when that bridge was designed and installed, however it may not have been standard to put protective barriers in front of support pillars adjacent to travel lanes.
It is surprising that the French government hasn't installed a safety barrier in front of those pillars.
However interesting recent observation: Walking in Nashville, TN saw exposed ROUND pillars (see photo below)
the address was 316 Woodland St Nashville TN
So guess many jurisdictions have exposed support beams and so the French situation is not unique.
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TRL Princess Diana.png (54.58 KiB) Viewed 62953 times
Which includes:
In January 2004, the UK’s inquest opened into the death of Diana, Princess of Wales and Dodi Al Fayed. Soon after the Met team were established, we were contacted by the Metropolitan Police’s lead investigator to discuss the assistance that TRL could offer the investigation. These discussions led to one of the most in-depth and innovative collision investigations of its time.
Having developed applications for new technologies in collision investigation, particularly 3D laser scanning, collision simulation and 3D visualization, and having introduced these methods to the UK courts for the first time during this period; my team and I at TRL were able to offer expertise in both conventional collision investigation and new cutting-edge methods. Applying these methods, we laser scanned the collision site in Paris, created the complex 3D road geometry of the approach to the Alma Tunnel and simulated the motion of the Mercedes. This approach was underpinned by extensive validation of the simulation model with a duplicate Mercedes S280 on TRL’s test track in Berkshire. This simulation enabled detailed analysis of the Mercedes’s movements as it approached and entered the tunnel, its loss of control whilst avoiding a vehicle near the tunnel entrance, the driver’s response and the ultimate collision with the 13th unprotected central pillar from the eastern entrance.
Comment
2004 was early to be using 3D laser scanning technology. Bravo for being at the cutting edge TRL.
For the 3D crash simulation we did in 1998 for 48 hours/CBS News we built the terrain models by hand and digitized the measured tire mark, etc evidence
With some adjustments to the 'measured' marks as we found some had issues once we started simulating and trying to match the marks
This allowed for direct evidence matching of the simulated tire marks with the measured tire marks so speed and control inputs could be adjusted to further refine the simulation reconstruction.
As an aside...We were somewhat surprised that we never heard a word from the 2004 UK inquest commission? You'd think they'd consider contacting us to check/verify/compare our 1998 work with their investigation/crash reconstruction.
Guess an over the pond oversight!
Today 3D Laser scanning is used extensively in the crash reconstruction community. Our msmac3D program has abilities and options to drive the 3D simulation on the 3D scans/images of the evidence
See our vrml file capability with msmac3D Graphics demo
The car was a major problem...it had been in a major rollover crash and was almost completely rebuilt. The car was known to behave erratically and drivers did not think it was right. Her driver was probably drunk, Princess Diana was not wearing a seatbelt...she was also sitting in the seat where the least forces acted during the rapid deceleration of impact and the subsequent rotation across the two lanes....A working auto-tensioning seatbelt, if buckled, would have saved her life and probably everyone else in the defective car.
Our Reply:
Not sure on the pre-crash rollover rebuild. Please send link to reputable source:did that come out in the Uk inquiry? If not its probably hyped BS.
And as far as survival, had they all had seat belts on they had ‘a best chance’ at survival but not guaranteed (especially the front seats with airbags and not having the rear seat unbelted passengers loading them after bad deployment)
BUT
a 50+ mph speed change is very high and can cause aortal separation, etc and is not guaranteed survival.
You are correct that in an offset collision seated location relative to the line of the collision force may be different due to rotation of the vehicle. But not that much
However In response I may post up the acceleration at each location to the thread “acceleration at locations other than CG” for a hypothetically similar crash. See this thread in the next few days DeltaV/Accel at location other than CG?
We also split off some information in a new Thread
Very interesting and highly technical...I give my students the analogy of Kepler's Law of planetary orbits to describe the relative decelerations and "swept areas" during a violent action in the same short time period. Stapp survived deceleration from 632mph to zero in around two seconds surviving approx .45 g force at commence of water brake deceleration.
Many sources, all reliable will confirm car's history..it was stolen in Paris and crashed, written off by insurance, subsequently bought by a mechanic and repaired. Other drivers for Etoile limousines have stated the car was difficult to handle at speeds over 45 km/h.
And our response:
In a search for sources most seem conspiracy theory 'news' sources, none from legitimate news sources. Did the 'rolled over totaled vehicle' issue ever come up in the UK inquiry? if so please send any links.
On the DeltaV by position:
Excellent observation! Had not addressed that! so...I did a msmac3D evaluation of a similar angled offset crash and see that the RR location is the least DeltaV (41.9 MPH) whereas most other locations are 50 MPH or greater
For similar crash simulation where CG DeltaV approximately 50 MPH...
i need to reload our actual crash reconstruction simulation from 1998, it was on a RISC6000 mini computer.
And for ANY DeltaV survival is never guaranteed. Obviously 41 MPH is better than 50+. Also i don't think comparisons with the Stapp test is appropriate...It was a sustained deceleration with peak of ~40 Gs (water decelleration and 4 point harness, etc.) however will give the acceleration traces a look/see in the near future since interesting comparison.
For a summary of the DeltaVs etc please see video and information below.
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and the summary of the smacthp DeltaVs from the msmac3D crash reconstrution:
Note that the msmac3D convention for X,Y,Z coordinates per the aeronautical sign convention (Z positive toward the earth!) (not cartesian (Z comin at you from your screen!)
acceleration summaries.jpg (389.23 KiB) Viewed 62904 times
That mercedes had a very dodgy past and that night it was the only one available
Our Response:
We've heard comments related to that, however, can you provide a legitimate news source which documents the 'dodgy past'. And the loss of control of the vehicle was due to excess speed for the downward left turn slope into the tunnel as the driver clipped the mysterious Uno and then in trying to recover overcorrected, lost contol and crashed into post#13.
Their additional comment:
watch the documentary death of diana the incredible revelation.
Our Response:
i looked for, found and quickly watched the conspiracy theory speculative show:
which had the car at OVER 100 MPH!!?? and bouncing from side to side in the tunnel?
And it looks like they used one? or both of the 'authors' from Dr Phil in the documentary! Brilliant!
A bunch of speculative nonsense.
To think a totaled , multiply rolled over car was restored and then sold to an executive limo service?
Does France not have laws where you have to reveal that a car was totaled as part of a sale?
And the UK inquiry missed this?
Why?
Because it probably wasn't 'totaled' and they simply ran with speculation to feed the conspiracy folks.
Provide documentation of
police report on the theft and rollover crash...
documentation of the repair work performed
the roof would have to be repaired and soooo much more
and then
the illegal sale hiding the fact it was totaled?
Obviously on a show folks interviewed can say ANYTHING
but show me the proof!
and even IF TRUE, it has nothing to do with the control loss.
The program did NOT report that had the driver NOT been drunk, NOT speeding and had there been simple barriers in front of the bridge supports, NO fatalities.
Additional comment:
chauffeurs who worked for etoile didn't like driving it and was difficult to control above 40
Our Response:
That may be, that may not be...
HUGE question:
how and why would this have been hidden?
Didn't the police and UK inquiry interview these folks?
Now 20 years later and with folks hawking and hoping to sell a book and documentary on the crash
They remember?
Why is it ONLY for a speculative show that they decide to remember the sketchy car?
And MOST IMPORTANTLY
sketchy or not
the car was travelling 70+ MPH down a grade to the left into the tunnel
The driver ran wide on the curve due to speed
The vehicle interacted slightly with the Uno
The driver's drunken over reaction and swerve first to left away from the UNO then to right to try to square with the lane and then back to the left into the post#13.
Not a sign of a sketchy vehicle, more a sign of a sketchy, speeding, drunk driver.
i understand the documentary is very professionally done, however it contains wild speculative sensationalism merely to feed folks things because it was a tragedy and folks simply can't accept that these type of drunk driving speeding crashes happen all the time.
AND of course they left out and i reemphasize:
Had the bridge support posts had any type of barrier in front of them they would have redirected the vehicle and produced scrapes on the car and not much more.
THAT is one of the major causes of death in this crash ignored in all these silly conspiracy theory click bait shows
Q: Was EDR data used? Are the seatbelt status and velocities confirmed by it?
Reply:
The crash was back in 1997 when EDR data was not available in the vehicle (to the public, maybe Mercedes could read something?) or for our analysis we did in 1998.
In 1997, the National Transportation Safety Board (NTSB) issued recommendations to "pursue crash information gathering using EDRs." NASA's Jet Propulsion Laboratory, in April of the same year recommended that NHTSA "study the feasibility of installing and obtaining crash data for safety analyses from crash recorders on vehicles."
In early 1998, the National Highway Traffic Safety Administration's Office of Research and Development formed a working group comprised of industry, academia, and other government organizations. The group's objective was to facilitate the collection and use of collision-avoidance and crashworthiness data from on-board EDRs. The working group published a report with 29 findings presenting an overview from users and manufacturers.
In 63 FR 60270, November 9, 1998, and 64 FR 29616, June 2, 1999, the agency denied petitions for rulemaking asking to require installation of EDRs in all new motor vehicles
The agency denied the petitions because the motor vehicle industry was already voluntarily moving in the direction recommended by the petitioners, and because the agency believed "this area presents some issues that are, at least for the present time, best addressed in a non-regulatory context."
also from other sources:
August 28, 2006: EDRs are regulated under 49 CFR part 563. Part 563 was established on August 28, 2006 (71 FR 50998) and requires that light vehicles equipped with EDRs meet certain requirements for data elements, data capture and format, data retrieval, and data crash survivability.
We had no access to any Mercedes internal data from the airbag modules in the subject vehicle.
The crash reconstruction we prepared and presented to 48 Hours in 1998 was based on a trajectory analysis (pre and post tire marks combined with a damage analysis (there were Mercedes full and offset barrier crash tests to provide stiffness properties).
We then tested and refined our findings for speeds and crash environment by creating the msmac3D crash simulation program which was a combination of the SMAC and HVOSM simulation programs.
For more information please see What is msmac3D?
"The Crown is, to its credit, too tasteful a series to show viewers the grisly car crash that killed Princess Diana, her companion Dodi Fayed, and their driver Henri Paul on Aug. 31, 1997. But we hear it happen twice—first as a sort of prologue to the sixth and final season, whose first four episodes are now available to stream on Netflix, and then, in its proper context, at the end of episode 3, as the most famous woman in the world flees Parisian paparazzi. The car disappears into a tunnel and then, almost immediately, comes the squeal of brakes and the crush of metal."
___________ Comment
We hope that anyone interested in the FACTS and the REALITY of the tragic event that occurred on Aug 31, 1997 will read this forum topic and come to the understanding that it was unfortunately a tragedy that occurs frequently throughout the world when vehicle travel includes:
Feb 2024: Comment posted to the video: Q: yes you covered everything except the fact the uno diver did not stop after the crash and was never traced.
COMMENT:
On the Dr Phil fiasco (mentioned earlier in this thread) where he claimed they found the UNO driver etc etc...
As mentioned in this thread previously:
Except for the loss of a side view mirror the vehicle was NOT damaged! Why did the driver (if the real driver) choose to leave the crash scene? Only the driver knows.
Was he afraid of being arrested for DUI or expired license or something like that?
If, as the alleged driver has said, he has spoken with police WHY was he not arrested for leaving the scene of a crash?
Was it due to a statute of limitations on the crime of leaving the scene of an accident (its been 20+ years!)? Or more likely perhaps the police DID NOT believe that he was the 'Uno driver' and did not want to give him an international stage to pretend he was!
It is surprising that the French police didn't trace the vehicle: do the French vehicle registrations include paint color (since they knew it was white?)
then again, how many white Unos were there in France at the time of the crash?
Now rewinding for a moment...
Imagine if you were driving the Uno and had left the scene of "a crash",
and you'd know it was a horrific crash
Since it happened in front of us after the Mercedes sped by and our cars briefly interacted
THEN we find it included a world famous person!
Now what?
i expect whomever was driving that Uno simply wanted to hide and not come forward
so might have had it painted,
definitely hid or destroyed it,
and somehow avoided detection
"If you are involved in an accident involving any sort of injury - even if it is not your fault - you MUST remain until the police have come. This is a legal requirement."
Also, the authors of the 'book about the crash" presented on the show do not know crash reconstruction
They said 100 mph and bouncing off the right side tunnel wall before slamming into Post#13...
That is simply WRONG!
Another post to the video: Q: The fact the driver left the scene is a crime in itself. In such a high profile case as this it's odd that person has never been accountable.
Comment:
We agree...
not sure what the situation is with the judicial system of France since
IF that person on Dr Phil show was 'the driver of the Uno'
WHY
Wouldn't the French police arrest him?
OR
Put out a notice that
They found the Uno and Uno driver and
They decided NOT to charge the driver because...???WHY???
My guess is that the Dr Phil 'Uno driver' wasn't the driver and wasn't the car and the French police still have not identified the Uno car that played the minor role in the tragedy.
And i say "minor role" since the drunk speeding driver might still have lost control in that curve and slammed into a different post
There were (and still are) NO guardrails or other attenuating devices in that tunnel to protect against out of control vehicles slamming into the posts
The crash was into Post#13 and there are many other support posts in that tunnel