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Re: spoilers

To: "Ferguson, Darrell" <dfergus@bactc.com>
Subject: Re: spoilers
From: "Thomas E. Bryant" <saltracer@awwwsome.com>
Date: Wed, 10 Nov 1999 10:00:17 -0800
Doug,

I know that I take the risk of being called "hostile" again by answering
this e-mail, but I have to give you, and the group, my views on the
subject.

I visited your web page and compliment you on your project. However, as
I view your car, the fact is that you have wing according to the rule
book. I'm interested in this discussion because I would like to be able
to run a wing as well. In fact George Fields was gathering signatures
Speedweek to allow Competition Coupe to run a wing. Don't you think it
would be more profitable to campaign for a wing in your class than to
try to change the definition of the spoiler?

The unhappy fact is that the rules don't allow for us to play catch-up
with the later model cars. A 1934 coupe, which I have chosen to run, is
a bit less streamlined than most anything I may compete with, but we all
have to apply the same rules. Good Luck with your project.

Tom  

"Ferguson, Darrell" wrote:
> 
> Hi Dan,
>         Glad you to hear you've visited our website, in reference to your
> comments regarding the legality of our car, The car is 100% legal per the
> 1999 SCTA rules for Altered Bodied Vehicles. If you've been a member of the
> land speed forum for any time, you'll remember the many discussions
> regarding the interpretation of the rules. As a result, I redesigned the
> front spoiler for my car (at considerable effort and expense) to be sure
> that I would, without any possible doubt, comply with the guidelines set
> forth by the SCTA. The rear spoiler on our car, does in fact have one
> Aerodynamic surface used to deflect the air for the purpose of spoiling
> lift. In an effort to guarantee stability, we decided to make the spoiler
> stronger by adding braces to prevent deflection, or failure at high speed. I
> hope we have not misinterpreted the SCTA's rule. I was led to believe that
> the rules' intent was for 1 surface to be used, not multiple surfaces such
> as those on a Top Fuel Dragster. If you are familiar with the NHRA's rule
> concerning "multistage elements" they restrict them to 3 separate surfaces,
> one behind the other, all at different angles. The NHRA imposed this
> restriction when someone discovered that 2 separate surfaces generated more
> downforce than one. As a result, everyone started running 2 elements on the
> rear of the car. Then someone said, if two work better than one, three
> should work better than two, again more downforce was realized, with minimal
> increases in drag. Soon the race was on with 4 and 5 element designs being
> deployed. Unfortunately, the increased downforce caused strut failures that
> would subsequently send the car out of control (now- no downforce with
> broken struts!). Finally the NHRA stepped in to limit the # of surfaces to
> 3. Along those lines, the SCTA has restricted racers in the Altered Class to
> only 1 surface, which my rear spoiler has and, I agree with the SCTA that
> multiple surfaces would allow spoiler designs to generate downforce at
> unsafe levels. My brother and I spent considerable time designing our rear
> spoiler to comply with the SCTA rules, making sure the spoiler did not
> exceed the measurements called for in the rulebook. I actually spent
> considerable time with an SCTA inspector, and a few altered class
> competitors, including Alan Fogliadini earlier this year at El Mirage
> discussing the legality of my car. I showed the inspector pictures of the
> car, and recited the rules regarding spoiler design and aerodynamic device
> classification from memory since I had reviewed the rules so often to make
> sure my car would be legal. He checked the 1999 rule book and agreed that
> the spoiler was in fact legal per class rules. While I cannot remember his
> name, he races the # 304 BBGALT Camaro, and in my opinion, I would expect an
> SCTA inspector to be critical about a different design, albeit legal,
> especially since he races in almost the exact same class as I do. When he
> gave his blessings, I assumed it as law.
>          In reference to the plates behind the car, we were unclear in the
> rules as to how the two plates would be classified. We refer to them as
> "chines" since there is no classification for any device within the
> paragraph outlining Aerodynamic devices that is even remotely close to our
> rear chines. We designed them with the intent of helping to keep the car
> pointed straight should we begin to go sideways at high speed. Also it will
> help prevent salt spray from corroding the parachute, mount, and cords.
> Other than that, there is no aerodynamic benefit of the two plates. Since we
> did not know how the SCTA inspectors would receive this new chine, and did
> not want to make the car illegal for competition in the altered class, we
> designed them so should the SCTA deem the chines, or plates illegal, then we
> would simply remove the 20 bolts that hold them on, and return to legal
> status. Again, this goes back to interpretation of the rules, and although
> we feel this will only make the car safer, we designed the two lower plates
> with that question in mind.
>         Since I started subscribing to this list, the topic of rule
> interpretation has come up frequently. I have heard comments ranging across
> the board. The most common have been that since my car is nowhere near as
> aerodynamic as a new thunderbird, or a 1990 Firebird, I will not be judged
> as harshly. I am obviously at a disadvantage to begin with using a 1968
> Firebird body for competition within a class dominated by vehicles more
> aerodynamic than mine. I've also been told that the faster I run, the more I
> will be scrutinized. While it is tough to interpret and enforce the rules
> for the wide variety of bodystyles, for me the rules should be a bit more
> consistent throughout the class. I designed the two plates for high speed
> stability. With my knowledge of aerodynamics and fluid flow from college,
> the two plates, if anything, are a disadvantage while the car is traveling
> straight, and aerodynamically buy me nothing. Should the car start to spin
> however, the idea is to help the car from coming around until I can slow to
> a safe speed, much like fins on a dart keep it pointed straight. If the two
> plates are classified by the SCTA as diffusers, and subsequently illegal for
> the Altered class, I will remove them. I am in total agreement with you Dan,
> I would be disappointed to have gone to such great lengths to keep the car
> within the Altered Class rules to be violated for a safety improvement. This
> is why we made them removable.
>         I would like to say thank you for your concern about our project.
> And your foresight to address topics similar to these at the upcoming rules
> meeting. I know that I, as will many others on this list, look forward to
> your reply.
> 
>         Sincerely
> 
>                 Darrell Ferguson
>                 BLACK RADON ENGINEERING
>                 # 939 BBFALT
>                 http://my.cybersoup.com/blackradon
> 
> > -----Original Message-----
> > From: Daniel Warner <dwarner@electrorent.com>
> > To: Land Speed <land-speed@autox.team.net>
> > Cc: Dan Warner <dwarner@electrorent.com>
> > Date: Tuesday, November 02, 1999 6:18 AM
> > Subject: spoilers
> >
> > Darrell,
> > Just visted your page to look at your project. Appears to be a fine piece
> > of craftsmanship, a vehicle to be proud of.
> > I am curious though as to your interpretation of the rear spoiler. As
> > referenced in your text a non-stock spoiler may be fabricated to the specs
> > called out in section IV-24h (misprint, should be IV-26h). The spoiler on
> > your car doesn't seem to meet the single aerodynamic surface rule. I also
> > reference page 53, last paragraph, 1st sentence "No streamlining allowed."
> > What caught my attention was the plates under the rear of the body which
> > look like diffusers(?). Please look at page 38, IV-26 Streamlining. The
> > opening paragraph defines SOME types of streamlining devices.
> > The intent of "No streamlining" and the section defining streamlining
> > devices is to point out that if the class is not allowed streamlining
> > anything under section IV-16 or appears to be non-stock for the class is
> > not allowed.
> > With the approaching date for the rules meetings I would like to be sure
> > that we are clear with the wording. It is difficult to present rules to
> > the
> > competitors who are out of the So Cal area. Locally we can communicate
> > with
> > each other directly concerning applications of the rules. We certainly
> > don't want someone building a car/bike and travelling several thousands of
> > miles to be out of class. It is not our intention to stop an entry from
> > running.
> > Dan Warner
> >
> >
> >

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