Summit Point Weekend Thread

[Tom Valet]

I am a big fan of attenuators, especially after Bill's big crash at Watkins Glen Pro race in 2011 when he backed into the wall, so no criticism of you Sam for making that piece, but for someone to try to push Jim down the straight by lining up on that small area seems crazy to me and asking for trouble.

[racerdad2]

Please do post photos of your attenuator, before the shunt. Incredibly strong & safe car... Thx !

[Tom Valet]

Please do post photos of your attenuator, before the shunt. Incredibly strong & safe car... Thx !

He already did.

[racerdad2]

Saw that. I was hoping for a little more detail.... obviously a good design....

[Mike Scanlan]

Here's a short clip, it's hard to tell since I couldn't figure out how to edit the .mov HD file, but the tire was still moving a bit when we came thru. My engineer, Jim Little, on the radio was all over this and told me to stay hot thru 10 and that I'd be able to pick my way thru it as the track was clear. It paid off. http://www.youtube.com/watch?v=jW_Ofzj1RM0

[EACIII]

Now if you could only overlay your radio communication with the video

Ed

[Michael Rand]

Another thought regarding the tire barriers and their construction.
A few years ago Brian Copperthite had a horrendous accident hitting the bolted together and massive tire barriers protecting the blunt end of the pit wall dividing Armco at Lime Rock.
He suffered injuries but has recovered to the point of making appearances, thankfully.
My point it, had those tires been simply stacked his injury may well have been far less severe.
Think about it, every tire sent flying is taking some of the energy needing to be dissipated with it.
The down sire of course is those loose tires would then be flying around and rolling down the track and pit lane.
The barrier at Lime Rock's West Bend often was smacked with exactly that scenario, tires rolling down the hill, drivers making extreme avoidances and at times losing control and adding to the accident.
So it is something to consider......

[problemchild]

While you can look at the glass either half full or half empty, Jim walked away, and his car will race again, perhaps by the next day. The tirewall did its job. The grown over berms may be more of a concern. Still waiting to see pics of the other Jim's F2000 car teetering on the hilltop.

[Bob Wright]

Having hit almost every type of thing you can around a race track....I would say concrete walls ruin your day more than anything else. Berms can launch you somewhere if you're going fast enough. Gravel traps, if done properly sort of stop you and usually end your session with a lot of cleanup. Fitch barriers work quite well but are a gawd awful mess to clean up. Tire walls, to my mind, are a great compromise. The problem with our cars are they are too light for a barrier of old truck tires bolted together and wrapped with rubber sheeting (WGI comes to mind immediately)- Its almost like concrete from the standpoint of tearing up equipment, but I think has enough give to lower the incidence of injury. Loose tires, as Mr Rand points out, dissipate energy better but fly all over the place and often cover you with stagnant water. The best I've seen (and can't remember where) are bolted together used race tires without any rubber sheet. You still get a shower, but the car doesn't get torn up as much.

We've come a long way in track safety in the last few decades. As a race track consultant, Mr Rand probably knows a lot more about this stuff than most of us. It still gives me the willies to think about what and where I raced back in the 70's and early 80's.

[racerdad2]

Perhaps tire stacks bolted together vertically, not horizontally.... ? Or loosely cabled together horizontally with about 6" - 8" of slack between the stacks. Tire columns placed tightly side by side. Upon impact allowing for movement & increasing resistance. Similar to pastic interlocking jersey barriers in karting.

[Dennis Valet]

Some good reading on tire barriers and their configurations

http://www.grandprix.com/ft/ftpw016.html


An SAE test was done to determine the best configuration. The report is here, but it's not free and I can't find a free copy anywhere else.

http://papers.sae.org/983061/

The tests revealed that this is the best configuration for energy dissipation



As a result, the FIA has mandated bolting tires together when they are in a barrier.

[racerdad2]

Excellent read !

[R. Pare]

My point it, had those tires been simply stacked his injury may well have been far less severe.
Think about it, every tire sent flying is taking some of the energy needing to be dissipated with it.

As noted above, from the SAE testing paper, having a bunch of loose tires that you can easily spear in between is not a good scenario - especially if the available depth before you hit something solid is short. A tire that stays in place and continues to be deformed will be still absorbing energy well after a loose tire starts flying.

That said, IF the depth available for penetration is long enough, loose, or not quite so much bolted together tires could possibly still stop the car before the final hard thump against a wall, and would do so with lower peak G's.

Wouldn't want to bet my life on it, though.

[Purple Frog]

The problem is that "it all depends". The best barrier for a GT1 car may seem like a brick wall for a F500.

[racerdad2]

In the ideal world, a 'lighter' first layer for small formula cars with progressively 'heavier' secondary & tertiary layers for heavier & faster cars. 'Progressive' resistance.

[Dennis Valet]

here we are discussing walls and how they are different for sedans vs formula cars... and yet those crazy asses on the motorcycles were running last year in the rain at Summit Point

Those guys are out of their minds. Fun to watch.

[racerdad2]

Agreed. I've several friends who've been that crazy. As nuts as I am, that's a quantum leap in crazy When you're young, you bounce. When you're old, you break. I got no bounce left in me... however, as the song goes, "Still crazy after all these years."

[Mike Scanlan]

Finally figured out how to edit a .mov file, now I just have to work on this wind baffled sound issue, but the video is good. As always, great racing throughout the pack in the F1600 Series. you tube at: http://www.youtube.com/watch?v=73k-t...ature=youtu.be

[stephen wilson]

Mike, I was curious as to why you take your hand off the wheel rim while cornering, knuckle clearance issues ?

[Mike Scanlan]

Knuckles clear just fine, the issue is with elbows and extension. The bars by my forearms have been pushed out which helped a bit, but I'm not a small guy. I've also gotten very used to using the CDS Co-Pilot dash as part of the wheel. I'm not actually taking my hand off the wheel, but rather pushing/supporting the wheel with my thumb.

[stephen wilson]

Ah, I guess you can get used to many things when forced to !

[Raceworks]

Saw that. I was hoping for a little more detail.... obviously a good design....

Finally got the time away from my other nefarious activities to snap some better photos.

"Before", or more accurately, the uncrushed attenuator on the other car:
https://www.facebook.com/photo.php?f...0&l=b068fc86b7

It's a pretty simple piece: 0.60" aluminum with a crapload of rivets, bolted directly to the wing mount.



Two pictures of "after" the first one at roughly the same camera angle, the second from the other side.

https://www.facebook.com/photo.php?f...0&l=6839507abd

https://www.facebook.com/photo.php?f...0&l=4e7dd2e207

We've been thinking of making some improvements:

• Using better quality rivets (stainless instead of aluminum).
• Adding some stiffening to the side panels (epoxy, or ribbing the side panels).
• Adding some foam filling to the first 6" of it, such as the stuff BSCI sells.

Of course, it seems to have worked pretty damn well as it is.

[R. Pare]

Your weak point in that design is the unsupported sides at the front - the box, when it got hit, just started folding on the left side and didn't absorb anywhere as much force as it could have.

To fix that, extend the top and bottom skins to the mounting block and bolt them there as well.

[racerdad2]

Thx guys ! Truly appreciate your sharing. Trying to make my Reynard as safe as practical. Hate to admit it... at 60 yrs things break easier & take longer to heal