Da Groj

We haven't been in this section of the forum in a while, let's see who's watching...

Link to coursemap in question:
http://dl.dropbox.com/u/804008/FAST-SPC_100516.pdf" onclick="window.open(this.href);return false;

The last sweeper before the finish was relatively fast, and some surface irregularities, and decreasing in radius the way a lot of folks were driving it, and perhaps a little overzealous driving, led to many spins/offs in the direction of the timing trailer. Even though there was more than adequate runoff room (min. 75 feet , per our insurance regs), and ultimately no harm done, in retrospect that turn was too fast, or perhaps too tricky?

I'm curious to know what others think.

It was not as safe as it could be. As safety steward for the event I take full responsibility. I choose to keep the corner fun to drive, with a nice flow rather than make it safe as possible. I only thought of one way to make it safer and it would have really sucked to drive. Sorry about that. We tried one thing, moved a wall about 10 feet, but I believe it wasn't enough. Looking back on it, we should have moved the entire shoot about 20 more feet away, I don't know what affect this would have had on the rest of the course.

Having said that, my car is pretty easy to rotate on throttle and it was planted through the finish every time. So I am perplexed at how people were losing it. I even asked people this at the event. Dunno, I guess they were out of shape long before the finish and then tried to save it instead of getting it back together.

People were loosing it from lift off oversteer / not taking a proper driving line and hitting the gas causing power oversteer. A lot of peoples first reaction when hitting the irregularity was to lift and the back would start to slide. The other slides I noticed were from people entering to fast and then turning harder while trying to speed up for the finish as they were going over the irregularity causing power oversteer. The irregularity is off camber and naturally decreased cars cornering ability ever so slightly unless you controlled your car while going over it. The problem is a lot of people lacked that control. They either lifted while turning or were trying to speed up for the finish to soon.

The couple of cars I saw were the ones not so easy to rotate on the throttle...that drove them wide through the turn. Especially with newer drivers not familiar with how to use lift-throttle oversteer to rotate an understeering car.

We've had a few layouts similar...now we know it's probably not a good idea.

Well, I can say I certainly learned a lot about designing a course at SPC...or more over, what not to do. But I agree, there is no reason for us to have the timing trailer that close to the end of a tricky turn again.

Personally I didn't see the corner as tricky, but I probably have enough experience to notice right away how not to drive it. I purposely used lift-throttle there to get the car to turn in then powered through it. The concept isn't drastically different from what the RWD cars should have done. The fact that the S2000's didn't lose it (yet are known for losing traction in the rear in situations like that) tells me it wasn't that dangerous of a turn. The real problem was aggressive, rough driving with on/off style throttle control.

We probably shouldn't have a turn like that close to the timing trailing and starting "grid"/line/whatever, but I certainly hope we keep turns like that, and I'd like to see them more, it really makes the driver learn what to do to get it right.

That turn was probably the 3rd most important there to get a good time. The most important was the first really sharp left hander (not the start one, but the one in the far corner that was 120 degrees or so), and second IMO was the big sweeper on the (if you are looking from the timing trailer) left hand side, since that determined how much speed you carried through the turn we are discussing.

This course was a momentum course, which was strangely fun (normally I don't like them since they tend to get repetitive and boring). You had to have throttle control to drive it fast.

Edit: Thinking about it, I'd love to see a novice school incorporate this type of turn, you can really teach a good bit just from that one turn.

There's certainly a learning curve (hah! get it?) to getting the layout with the right combination of fun and margin of safety. It was definitely a fun corner, and I sure hope there's more of them. In fact, there should be in order to give folks the opportunity to practice control in higher speed sweepers like that.

I think with the timing loop right there know one wanted to let off.

I don't think there's an issue with the feature itself -- a perfectly normal bend. Simply that it probably should have been another 30 feet or so away from the trailer to make sure everyone was straightened out by the time they went by. In part, we set ourselves up because I tihnk we've started positioning the trailer a little further back, in order to clear the view from the picnic tables as a means of keeping the spectators from crowding the trailer. We'll simply have to be slightly more clever in course design and where we perch the trailer. As with any real estate deal, it's all about location.

It was too close to the trailer, but the layout was fine. It was a wonderfully entertaining turn. If you did it wrong you were slow or backwards. If you moved it farther out from the trailer, it would have tightened up the second half and could have made for more wipeouts. And it would have been slower. And less fun. Less this Yellow_Colorz_PDT_01 and more this Yellow_Colorz_PDT_13

We could move the trailer. Maybe set it up in front of the garage where El Presidente parks.

AScoda wrote:
We could move the trailer. Maybe set it up in front of the garage where El Presidente parks.

I think thats the solution if we have enough rope for the timing gear, otherwise I see no reason to have it anywhere near as far into the pad as we normally do.

yamaha731 wrote:I think with the timing loop right there know one wanted to let off.

Exactly. So we need to allow for that in a safe (r) fashion.

Jamie wrote:I tihnk we've started positioning the trailer a little further back, in order to clear the view from the picnic tables as a means of keeping the spectators from crowding the trailer.

We actually did move the trailer, further in line of view of picnic tables, as its original place was even closer to the turn.

Charles wrote:

AScoda wrote:
We could move the trailer. Maybe set it up in front of the garage where El Presidente parks.

I think thats the solution if we have enough rope for the timing gear, otherwise I see no reason to have it anywhere near as far into the pad as we normally do.

NOOOOOO!! Yellow_Colorz_PDT_04
Actually, that's a really good idea. Timers ought be able to see the action well enough, and in fact will be able to see who's headed to the start line easier. Can the timing cables handle being run over by cars all day long? And if we grid cars facing the course, the foot traffic between grid and trailer won't get in the way of cars heading to the start line.

AScoda wrote:We could move the trailer. Maybe set it up in front of the garage where El Presidente parks.

Nice. I nominate Drew to coordinate the next SPC event. LOL.

Native wrote:Can the timing cables handle being run over by cars all day long?

Not really.

Jamie wrote:

Native wrote:Can the timing cables handle being run over by cars all day long?

Not really.

But a cheap plastic runner to cover up the lines can be had cheap at home depot. Just need about 10' (maybe 2 five footers) and place cones on either side so everyone goes over the runner and not the lines. Easily taken care of. 8)

I wasn't there, but I'm curious...

1. What was the ACTUAL distance from exit of the final turn to the trailer? Did we achieve our 75'? More?

2. How close to the trailer did the cars that wipe out actually get? 10'? 20'? 30'?

In other words, did we meet the guidelines? (Steve's initial write-up indicates that we were) And was it just "a little scary looking" or was it "actually dangerous"?

I'm trying to feel out our safety parameters here. Y'all are a little up in arms here because it was the trailer... but we have typically no more than 75' on the outside of turns like this on nearly every course at SPC. The outside of the turn could be a curb, a guardrail, a fence, whatever... but the situation is not at all uncommon. All that was different here was that the obstacle was the trailer.

75'... safe, or not safe?

Loren wrote:...did we meet the guidelines? (Steve's initial write-up indicates that we were) And was it just "a little scary looking" or was it "actually dangerous"?

I believe we did (based on eyeball estimate -- I wasn't doing safety, so didn't pace it off), and more the former.

I did pace it off. From the closest corner of the trailer to the closest end of the finish line was 60'. I knew it was kinda bad but I didn't see any way to move the finish 15' and not have it suck. Eric wanted to move it into the corner but I told him that I didn't want the finish line in the corner. We ended up moving the wall before the finish about 5 feet out more, to try and corral people into the finish lane.

I used my experience from the decreasing sweeper in Gainesville and I have never seen a car go off at the very end of a decreasing sweeper, it's always mid corner, and I have seen a ton of cars go off there.

Where the number 4 is on the map, there was a huge pile of cones that were unloaded from the trailer. Joe came within a few feet of them (Hindsight: They shouldn't have been there). I also saw Shon spin, both spun sorta parallel to the trailer. Both were tank-slappers, I think. I heard the Mercedes spun in the 4th heat but I didn't see it.

Okay, given that description, the trailer wasn't really a factor in the turn. (and that's sort of the way it is on the map... but I like to think conservatively and "worst case", that's why I suggested 75' from the very exit of the turn to the trailer in the initial design discussion) If anyone spun IN the turn, they had 75'. If they spun at the very exit of the turn, they still had 65'.

The cars that lost it were THROUGH the turn, and it sounds like they pretty much stayed within the 25' zone that our insurance designates for a straight.

I think it's pretty cool that those numbers generally prove to WORK. And I want to point out that they WILL NOT work at speeds higher than the 60 mph that they're designed for. (not an issue at SPC, but can be an issue if we're not careful at Brooksville) 8)