Nathan made the announcement a few days ago (in a Radon thread). Where you been Len? Building houses?
Since this is the FC safety thread... i was thinking your "big one" at Lime Rock a few years back may have effected your memory.
Nathan made the announcement a few days ago (in a Radon thread). Where you been Len? Building houses?
Since this is the FC safety thread... i was thinking your "big one" at Lime Rock a few years back may have effected your memory.
Originally Posted by Purple Frog
Nathan made the announcement a few days ago (in a Radon thread). Where you been Len? Building houses?
Since this is the FC safety thread... i was thinking your "big one" at Lime Rock a few years back may have effected your memory.
I've known Len for a number of years, trust me, he was "Effected" way before the "Big one at LRP"
Out of curososity, I too am looking forward to seeing the Radon Pictures and what possible saftey innovations it may have.
AMBROSE BULDO - Abuldo at AOL.com
CURRENT: Mid Life Crisis Racing Chump/Lemons Sometime Driver (Dodge Neon)
CURRENT: iKart Evo Rotax 125 Kart
GONE: CITATION 87/93 FC - Loved that car
GONE: VD RF-85FF , 1981 FIAT Spider Turbo
smaller unsupported plates
all of the previous discussion assumes a "fixed frame" and focuses on the plate stiffness of available material options which are driven by thickness/density. in a more general sense, plate deflections are a function of the plate's stiffness,a function of the plate's size and shape, and the boundary condition(s) along the perimeter of the plate. the GCR limits attachment of approved lateral intrusion protection materials to the frame so there's little or no room for improvement
in boundary conditions along the perimeter. frame tubes to provide support for lateral intrusion protection material are sparse in most frames therefore resulting in large lateral instrusion plates; ie: the larger the plate the larger the resulting deflection for any given load for any assumed stiffness.
for discussion simplicity, assume a steel space frame with heat treated aluminum attached to the frame on 6" centers for compliance with the GCR's lateral intrusion protection requirements (more likely to stay attached than most bodywork). while adding steel tubes to reduce the size of the lateral intrusion plates to improve lateral intrusion protection would work, it's a heavy approach and could only be done with a bare frame. while strictly speaking not a frame tube, imagine adding (ie: rivetting) extruded aluminum square tube, Z-section, or C-section to the back of the aluminum sheet approximating "frame tubes" from the three corners of the triangular plate to its center. plate stiffness is now no longer a function of just thickness cubed AND the size of the effective plates would be much smaller. taken a step further, aluminum on the inside of the frame could be attached to the extruded aluminum square tube, Z-section, or C-section attached to the aluminum on the outside of the frame creating a fabricated "I-beam" of sorts with much greater lateral/transverse stiffness. per the GCR, aluminum sheet material attached on 6" centers or greater are not stress bearing and you can't have a monoque structure without stress bearing skins! if the outer aluminum lateral intrusion protection material can be shaped without welding, 7075-T6 for improved yield stress looks like an attractive way to go; otherwise 6061-T6 probably provides the best readily weldable choice. I for one would like to see 6-4 Titanium approved for lateral intrusion protection. rivetting is something almost all competitors can do, rivetting is something that can be done incrementally, and extruded aluminum square tube & Z-section are reasonably light on a specific stiffness added basis. smaller unsupported plates for improved driver protection is something all competitors can currently do with the rules as currently written.
Art
artesmith@earthlink.net
Last edited by Art Smith; 06.21.11 at 9:58 PM.
Art, I have been kicking around a very similar idea, using riveted & bonded 1" Aluminum honeycomb panels between the inner and outer skins.
I had a conversation with someone at the Sprints who suffered a side impact injury in their FF. When they got to inspecting their bodywork from one of the major body manufacturers, they discovered that there was basically no kevlar in it.
Hearing that plus seeing the pictures of Paul's side panel from the F2000 race at Watkin's Glen tells me that we have a problem with cars not being compliant to the rules right now.
Tim Paul's bodywork definitely had Kevlar in it, and as far as we can tell it is the mandated two layers of five ounce cloth, and therefore compliant with the existing rules.
However, that much (.020") Kevlar is essentially useless, especially in a glass/polyester panel that isn't structurally supported.
Nathan
I will believe it when I see a picture of it.
Wren, why would you not believe people who looked at the car up close, especially someone who has direct access to the prep shop that takes care of it?
I also inspected the car at the event and there was at least some Kevlar in the side panel, what little good it did. I drive the same model VD, so I'm kind of interested....
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In memory of Joe Stimola and Glenn Phillips
Because I didn't see any kevlar in the pictures and there are agendas involved. Throw in other people reporting not having kevlar in their bodies and this body being not a stock VD piece and it is pretty easy to understand why I don't believe it.
Unfortunately another example of an intrusion this weekend at Mosport.
The first shot is from the gas pedal looking towards the fuel cell. The little thread hanging on broken fastener is from the driver's suit.
The anti-intrusion bar did not break off the A-arm, it just folded.
Last edited by Purple Frog; 09.26.11 at 10:40 PM.
I see no evidence of kevlar; am I missing something Mike?
No John, you are on point.
I'm pointing out that some are not even taking advantage of options that currently exist. And that it is a danger point.
IIRC the kevlar is only required between the dash hoop and roll hoop. If you get a penetration in front to there the Manufacturer probably didn't put it there.
Not required, but not prohibited.
The one thing the pictures show the need for is that the anti-intrusion tubes need to really be much more substantial that the usual 3/8' or 1/2" tube.
I hesitate to post pictures of damage.
I try to spend a lot of time inspecting post crash damage to get smarter. In single car crashes I'm looking for possible component failure.
In this case the car went off in T4 at Mosport at a high rate. There was a tire wall, but the car penetrated the tire wall and impacted the concrete wall behind at about a 30 - 45 degree angle. The driver admitted just missing his correct turn in point.
The front crush structure worked as much as it could, but was probably inadequate for that speed. I like some of the stronger designs, such as the one in the Spectrum we saw at M-O.
The tires from the tire wall were projectiles bombarding the driver's head and roll hoop.
The driver climbed out.
It points out the extreme importance of the use of a HANS type device. ...and proper submarine belts.
Also, because of the quality of the full face helmet and shield, the driver was not hurt badly by the tires coming at him. Also, it highlights the importance of a proper headrest.
The chassis is a bit tweeked as evidenced by a small warp in the battery box area. It does show the strength of a tube frame structure in terms of integrity of the driver's compartment.
Although not a major component, nor really heavy, recently I've become more concerned with the shock covers on these cars becoming projectiles. I wonder if they should be tethered. Over the past few years i remember numerous instances of them flying off. And in some frontal impacts they are driven rearward towards the driver. If they had tethers tying them to the front bulkhead, teams could still lift them for shock settings, etc.
Last edited by Purple Frog; 10.14.11 at 10:49 PM.
Maybe we should rethink how we report accidents.
I find it very helpful to see the various failures that happen in crashes. It helps me improve my cars.
The FAA publishes reprots on accidents of aircraft. The idea is to improve safety.
It appears to me that the car held up quite well but some things may need attention to improve the car. Many ideas could be retro fitted to existing cars. Maybe we need to adjust the rules in some areas to improve safety. Something like "stress bearing panels" behind suspension pickups to help prevent intrusion into the cockpit area after a joint failure.
Without seeing the results of wrecks we loose an important source of information to improve the safety of our cars.
As an example, I see that it appears that the nose box failed at the mounting point instead of crushing progressively back to the bulkhead.
The crushbox on the FE cars made of honeycomb seems like it absorbs more of a frontal impact from the crashes I have seen. Might be worth a consideration.
Is it time to ask more of the tracks for safety? The hard hit that I have had was after I nosed right through a tirewall into a concrete barrier as well. It seems more heavily bundled tirewalls help versus individual stacks.
Conveyor belt surface cover seems to help a good bit as well from what I have seen.
jim
I agree with Steve, I'd very much like to have access to a description and photos of formula car (and maybe sports racer) accidents. For those cars that have data, it might be possible to include relevant speeds.
Mike Eakin documents the results well in the F2000 pro series, but I'm not sure how it is done in club racing.
I looked at the chassis pretty carefully. My basic conclusion is that the tube frame held up quite well but the crush box wasn't adequate (although I'm sure it meets the rules). The wishbone intrusion was truly scary. Like Tim Paul's accident at Watkins Glen, a couple of inches either way and the injuries would have been severe.
Two or even five layers of Kevlar in the bodywork, or larger anti-intrusion bars, would have made no significant difference in this case. The anti-intrusion bars only work if they have something to react against. The best way to prevent intrusion of front suspension members is with an anti-intrusion panel solidly mounted to the tube frame chassis. It's how every modern formula car addresses the problem. Steve's suggestion of stressed panels behind the pickups would likely work well, and wouldn't introduce any competitive advantage.
Nathan
Nathan,
I've trained under a good mentor, Fred Clark.He taught me to record with photography. He sends pictures on into Topeka from SCCA events, but not onto public forums AFAIK.
I decided a while back to go a bit more "public" when I realized how many constructors and amatuer constructors are out there that don't get to see outcomes. I believe the synergy of all those brains that are better than mine, will keep improvements coming.
Granted, i am on a bit of a crusade for drivers to use equipment such as the Hans, and maybe a photo will wake up those doubters.
I believe Bob told me they were tripping along about a buck twenty at the start of the off. Witnesses said the grass didn't slow the car down much.
Stacks should be bolted together at the minimum
I'm surprised that the track insurance company would still allow individual tire stacks, but since the track is in Canada, the rules may be different.
I believe that here in the States, most if not all insurance companies require that the tires all be bolted to each other - both vertically in an individual stack, and from tire to tire in adjacent stacks. Then again, that requirement may have been only at the Florida track where a friend was contracted to bolt the tire stacks together a few years ago.
Penetration into the driver is a big concern in formula car racing, so anything that can be done to help reduce it should be welcomed. The problem becomes implementation across 25+ years of designs.
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