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Richard Lewis
03-24-2003, 01:23 AM
We seem to have little to no luck these days... Murphy is against us. For our 3rd event in a row, we've had some sort of catastrophic failure. (over a period of many months mind you) This is the summary I sent to our team about the event, I thought it might be prudent to share some of our experiences with others however. This is damage done to our 2002 car.


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Well, Colin, Patrick, Clayton and myself took UV02 out to western speedway for the first "slalom" of the year. It wasn't much of a slalom as average speeds among the street cars were probably in the 110km/h range...

We had 2 minutes of rain just after Patrick and Colin took their practice runs. We waited it out, and got to continue going with a dry track. After some issues for both Patrick and Colin in the practice run, both guys put in a really decent first run and sorted out their problems. (the car was twitchy on the uneven pavement and shifting was a bit finnicky)

The day turned sour on Patrick's second timed run. We have a pretty good idea of the sequence of events, since I was snapping photos at the time. Coming out of the hairpin (likely) the lower front right a-arm rod end plug had its weld break. Likely friction held it in place for the next 100m or so of the track, and then it let go completely on the back straightaway, with Patrick doing in the area of 110km/h. Of course, as soon as this happened, Patrick lost steering on one wheel all together, and the wheel aimed wherever it felt like. Pat did a great job scrubbing off speed and keeping the car in as much control as he could manage, but hit the wall, rear left corner first at what I estimate to be 30km/h or so.

The car is in bad shape. the rear of the frame has buckled and broke, rear a-arms are toast, CV looks bad, 1 wheel bent, 2 shocks are questionable, pull rods bent, muffler crushed, tail light broken. In the front, the a-arms and tie rods took a beating from the loss of alignment and a subsequent touch with the wall. Patrick hit the wall hard enough to bend the seat with his back, and pull the steering column out of the rack. We took him to a doctor to be safe, as he hit backwards and had a bit of a headache. Sounds like he'll be a bit sore tomorrow, but overall he's fine according to the doctor.

The car can be repaired, but probably will not until after we return from Detroit. The damage is about 50% greater than what occurred in our last event in Everett.

I guess the most important thing to take from this near catastrophe, is learning how to avoid it again. Yes, these cars are fairly safe to crash in, more so than most streetcars. However we still need to take precautions. We should make a new front crushzone and USE IT. We should think about a rear crushzone as well. Seatbacks should be padded at least slightly. Anything the drivers knees can hit should be padded. Roll bar padding should be to spec at least.

Had this been a head on collision without the crush zone in place, Patrick may have suffered a serious leg injury. We need to rethink driving a car that was designed for running at a 105km/h top speed, on a course that it will see 150+km/h on, with concrete walls, on broken pavement and with dust and gravel on the track at times.

Today I learned a very valuable lesson about the cost of failure in engineering. Hopefully someone will learn the same lesson from me writing this, without having to go through the experience themselves.
------------------------------------------------

Yes we made some poor decisions along the way. (discaring our crush zone because it wasn't practical, and never replacing it) And some design decisions that were questionable as well, as this was our first car. For myself, it was a very sobering reminder of what can go wrong.

-------------------------
UVIC Formula SAE Team
http://members.shaw.ca/drax77/Formula%20UVic%20Sig.jpg
http://uvic.fsae.ca

Richard Lewis
03-24-2003, 01:23 AM
We seem to have little to no luck these days... Murphy is against us. For our 3rd event in a row, we've had some sort of catastrophic failure. (over a period of many months mind you) This is the summary I sent to our team about the event, I thought it might be prudent to share some of our experiences with others however. This is damage done to our 2002 car.


-----------------------------------------------
Well, Colin, Patrick, Clayton and myself took UV02 out to western speedway for the first "slalom" of the year. It wasn't much of a slalom as average speeds among the street cars were probably in the 110km/h range...

We had 2 minutes of rain just after Patrick and Colin took their practice runs. We waited it out, and got to continue going with a dry track. After some issues for both Patrick and Colin in the practice run, both guys put in a really decent first run and sorted out their problems. (the car was twitchy on the uneven pavement and shifting was a bit finnicky)

The day turned sour on Patrick's second timed run. We have a pretty good idea of the sequence of events, since I was snapping photos at the time. Coming out of the hairpin (likely) the lower front right a-arm rod end plug had its weld break. Likely friction held it in place for the next 100m or so of the track, and then it let go completely on the back straightaway, with Patrick doing in the area of 110km/h. Of course, as soon as this happened, Patrick lost steering on one wheel all together, and the wheel aimed wherever it felt like. Pat did a great job scrubbing off speed and keeping the car in as much control as he could manage, but hit the wall, rear left corner first at what I estimate to be 30km/h or so.

The car is in bad shape. the rear of the frame has buckled and broke, rear a-arms are toast, CV looks bad, 1 wheel bent, 2 shocks are questionable, pull rods bent, muffler crushed, tail light broken. In the front, the a-arms and tie rods took a beating from the loss of alignment and a subsequent touch with the wall. Patrick hit the wall hard enough to bend the seat with his back, and pull the steering column out of the rack. We took him to a doctor to be safe, as he hit backwards and had a bit of a headache. Sounds like he'll be a bit sore tomorrow, but overall he's fine according to the doctor.

The car can be repaired, but probably will not until after we return from Detroit. The damage is about 50% greater than what occurred in our last event in Everett.

I guess the most important thing to take from this near catastrophe, is learning how to avoid it again. Yes, these cars are fairly safe to crash in, more so than most streetcars. However we still need to take precautions. We should make a new front crushzone and USE IT. We should think about a rear crushzone as well. Seatbacks should be padded at least slightly. Anything the drivers knees can hit should be padded. Roll bar padding should be to spec at least.

Had this been a head on collision without the crush zone in place, Patrick may have suffered a serious leg injury. We need to rethink driving a car that was designed for running at a 105km/h top speed, on a course that it will see 150+km/h on, with concrete walls, on broken pavement and with dust and gravel on the track at times.

Today I learned a very valuable lesson about the cost of failure in engineering. Hopefully someone will learn the same lesson from me writing this, without having to go through the experience themselves.
------------------------------------------------

Yes we made some poor decisions along the way. (discaring our crush zone because it wasn't practical, and never replacing it) And some design decisions that were questionable as well, as this was our first car. For myself, it was a very sobering reminder of what can go wrong.

-------------------------
UVIC Formula SAE Team
http://members.shaw.ca/drax77/Formula%20UVic%20Sig.jpg
http://uvic.fsae.ca

Denny Trimble
03-24-2003, 02:36 PM
Sorry to hear about the damage to your car, I'm glad the driver wasn't hurt. We've had a few scary suspension failures in the past, luckily at lower speeds and not near any walls. These failures have taught me lesson as well.

I'm going to start a thread about factors of safety in the Open FSAE Discussion forum.

By the way, we're putting on another autocross on April 13th at Boeing-Everett. www.wwscc.org (http://www.wwscc.org) will have the details soon.

-Denny Trimble

University of Washington Formula SAE ('98, '99, '03)

Andy K
03-24-2003, 09:47 PM
Glad to know that none of you was hurt in the incident... Hope you guys get it up and running in time for the competition.

Andris Kanins
McGill Racing Team - Body Design

Patrick W. Crane
04-14-2003, 02:06 AM
hmm.. suspension failiure resulting in a spectacular crash eh... seems we are not the only ones to have this happen to us.

Just to clarify, it was last years car that we were racing not this years. So it doesn't affect us as far as Detroit goes.

See you in detroit
Cheers

-Winston

110km/h, no steering... no big deal.. the concrete will slow me down.