LM News - Peugeot Shunt

[Shug]

Ouch Caught on Le Mans security cameras...

http://youtube.com/watch?v=gSsorp6F36s

[graeme]

Crikey!

[DDtB]

Problem was the diesel on the track ....

[Matelotman]

ooya

[Dominic]

Le ouch !

[dlogan]

Seems to be a fair few of these type of "air underneath" happening recently with the prototypes.

Very remeniscent of Dumbrecks mercedes "backflip" a few years back.

On another note, turned over the desktop calendar today (just a random freebie) and it explained that on todays date in 1955 was the biggest motorsport crash in Le Mans history with 82 spectators killed. I knew about the crash and have seen the footage but some interesting facts on it here:

http://en.wikipedia.org/wiki/1955_Le_Mans_disaster

[Shug]

Any time you get basically flat-bottomed cars, you have the danger of flipping. The key thing with this is it was a freak accident, car flipped sideways, not going forwards like the Mercs did. Front overhangs are pretty short now, which was the reason for the Merc flipping (porpoising on the straight, combined with the hump on the Mulsanne - bad timing, caught the underneath and wooof!)

Always gonna happen sadly, ever since Group C days, it's been happening... Not a lot that can be done, other than reduce the footprint of the cars & make the roll protection bloody good (which is another reason the ACO are moving towards closed prototype rules again)

[dlogan]

Any time you get basically flat-bottomed cars, you have the danger of flipping. The key thing with this is it was a freak accident, car flipped sideways, not going forwards like the Mercs did. Front overhangs are pretty short now, which was the reason for the Merc flipping (porpoising on the straight, combined with the hump on the Mulsanne - bad timing, caught the underneath and wooof!)

Always gonna happen sadly, ever since Group C days, it's been happening... Not a lot that can be done, other than reduce the footprint of the cars & make the roll protection bloody good (which is another reason the ACO are moving towards closed prototype rules again)

Yep, but the monza crash a few weeks ago was exactly the same scenario. Lost it and it was "sideways" when it flipped, just missing chopping the audi in half, and make a similar destruction job to the Pugget above.
There have been others this season too, which have flipped in similar fashion. Didnt think it had been a problem since the Mercs problems up till the start of this season. I might be wrong, but was just an observation.

Its on you tube but cant get the link or access from work.

Doesnt stop me from being grumpy as I wish I was there!

[Mikie711]

Same thing happened to the Mazda at Le Mans tonight during the second session of qualifying. Hit the kerb sideways and took off. Rolled a couple of times driver walk away. Not much left of the car though.

[Shug]

As long as they walk away and it's a result of a driving error, fair enough... What'd really start to worry me is if the cars were to start spontaneously start doing it on the straight again (a' la Merc) or people were getting hurt. I remember Thierry Boutsen's sickening thump into the tyres in '99 in the Toyota - that was pretty bloody scary

Pretty harsh punishment for a mistake, but Le Mans has always been for grown ups

[jason]

It wasn't just Mercedes that flipped in the late 90s... Porsche experienced it too http://www.youtube.com/watch?v=HIxKoCueD5M.

The Merc and Porsche flips were caused by a combo of being in disturbed airflow - following another car - and going over a crest... an instability that I think has been cured since. But unless they permit the reintroduction of full ground effect bottoms - hence avoid totally flat undersides - I don't see how they can prevent these latest airborne accidents...

...unless they try roof flaps like those successfully used in Nascar.

[Shug]

The Merc and Porsche flips were caused by a combo of being in disturbed airflow - following another car - and going over a crest... an instability that I think has been cured since. But unless they permit the reintroduction of full ground effect bottoms, I don't see how they can prevent these latest airborne accidents...

Yup - combo of porpoising, the front end not having as much downforce behind another car (hence more space between splitter and ground) then popping out into the 200+mph airflow and it gets under the front end. All caused by the overhangs on the GT1 spec cars - I think overhangs are legislated now, so you can't sit the front wheels half-way back along the car for a smoother front splitter I think they didn't use 3rd spring arrangements on the fronts either - something the first Bentley LM car didn't use, but the second one did - supposedly made it a different car in terms of aero stability, as the front ride height was properly controlled.

Will always be a danger when you have essentially ground based reverse-aircraft. They go north pretty f**kin quick in a 200 mph airflow!

[jason]

Ah... didn't know the overhangs had been further legislated, thanks

I assume the regs folk have consider the use of Nascar stylee roof flaps... they certainly do their job there http://www.youtube.com/watch?v=k7K4Vd396kU.

Though aero-wise the cars are very different, when going sideways surely an LMP car's aero has stalled so it's actually a very similar situation... ie. flat bottomed projectile with air pressure building underneath it?

[Mikie711]

There is talk of a huge rethink of the regs to try and slow the cars down. Any of these cars can and do get airborne if the hit a big enough bump. As has been said flat bottom cars act like a wing when they loose down force resulting in spectacular crashes. Le-mans this weekend, and know doubt there will be more flying as well as driving. As long as they all walk away..................

[jason]

And another flip yesterday.... Lola Mazda of Hideki Noda flipped after spinning sideways into gravel - ie. air got under it, as opposed to digging into the gravel and rolling.

Autosport report here http://www.autosport.com/news/report.php/id/68220
Video here http://www.youtube.com/watch?v=GkjOv2HJeZM