The Clarinval S22 was a clean-looking machine.

Two closeups of the CS22's suspension, front and rear.

Type: all-composite race car



Powerplant: unknown

Significant date: 2000

Scaled Technology Works (STW) of Montrose, Colorado (Scaled Composites' once manufacturing subsidiary), entered into an exclusive agreement with Aeolus Technology, LLC to provide composite structures for their line of racecars. Aeolus Technology LLC of Fort Collins, Colorado, selected STW initially to produce composite body parts for a new racecar that would be competing in the SCCA sanctioned ACRL (American Cities Racing League) professional racing series. The S-2000 car was one of several new racecar designs that Aeolus expected to introduce to the industry in the next 2-3 years.

The S-2000 racecar market alone was estimated to be up to 8 cars per year. STW would ultimately provide all composite components for the complete line of Aeolus racecars. STW's contract could eventually include structural design, tooling, fabrication and assembly for composite chassis and bodywork. The racing industry was evolving into the high-technology world of composites that had been enabling technology for many aerospace applications in recent years. "This industry is realizing the advantages of composites, and is switching from tube and aluminum skin racecars to high tech composites," said Bill Wailes, Chief Operating Officer of STW. "The high strength to weight ratio of composites allows racecars to achieve the light-weight, high-performance designs mandatory to compete on today's high technology racecar circuits," said Wailes.

The racing industry is very fast paced and exciting. "The technology is an ever changing evolution," said Alain Clarinval, Technical Director, Aeolus." With Aeolus' design of the S-2000 and our future racecar designs coupled with STW's production capabilities and knowledge of composites, our team will provide a strong technical advantage over the competition," said Alain. STW will apply the same application of high technology, innovation and diligence that has made it and its sister company, Scaled Composites industry leaders in the implementation of advanced composite structures. At STW the Company's main focus has been to provide design, certification and serial production of innovative composite structures for the general aviation and commercial aircraft and space launch industries. "This new venture will allow STW to showcase our capabilities in other composite fields," said Wailes.

On Feb. 18, 2000, AEolus Technology and STW announced the presentation of the Clarinval Supersport 22 (better known as the CS22, or even plain S22). The car was unveiled at the STW Facility in Montrose, Colorado. AEolus Technology, the engineering research and development firm producing the CS22, based its philosophy of aerodynamics on its namesake, the Greek god of the wind. "We are very proud to be part of this exciting new racecar program," said Bill Wailes, Chief Operating Officer of STW. "STW has applied our proven, low-cost aerospace technology to the production of the body for the inaugural CS-22 car." In addition to design input and fabrication of the composite body, final assembly of the CS-22 car was accomplished at STW's high-tech facility.

The Clarinval S-22, Sports 2000 competed in the American City Racing League, with both Eastern and Western divisions. This vehicle offered an innovative approach, which incorporated a composite chassis with an aluminum honeycomb core and pre-preg fiberglass materials. The suspension was a pushrod actuated passive hydraulic system designed to maximize the car's performance. The CS22 was conceived using the latest competitive techniques, creating a new standard of the Series for many years to come. The aerodynmaic concept played a key factor in the car's architecture, it's influence defining highly efficient forms. All components of the car have been subjected to 5 main considerations: maximum performance, safety, reliability, efficiency, cost and maintenance. Many of the elements are unique and not to be found on any other vehicle of this type.

Alain Clarinval, designer and aerodynamicist brought 35 years motorsport experience to the CS-22 project. Clarinval noted his pleasure introducing this new vehicle: "This is the beginning of a long dynasty of competitive cars that we intend to bring to the racing market. Our relationship with STW allows us to expand our production capabilities by utilizing the strengths of a leading composite company." Up to eight S-2000 cars were likely to be produced annually. STW eventually expected to provide all composite components for Aeolus' complete line of race cars.

Unfortunately, STW went bankrupt some time in 2003, and S-2000 production was never to be. The following year, the Colorado State University Mechanical Engineering Department acquired the retired S22. The CS22 racecar originally had a hydraulic suspension, which, for then unknown problems, had caused the race team grief. Eventually they had exchanged the hydraulics for a standard mechanical suspension after some time, with a bit of modification to the car. That was the configuration of the vehicle when the CSU team, led by Dr. Patrick Fitzhorn, took possession of it. Along with this car, the University acquired the components of the hydraulic suspension.

When CSU acquired the car and the original hydraulic suspension parts, the only evidence of how the hydraulic suspension was mounted were the holes drilled in the front plates and two very grainy pictures of the front hydraulic suspension mounted on the car. The goal of their project was to reconstruct this suspension off of the car. In cooperation with another project within the Sound and Vibration REU, a computer model of the hydraulic suspension would also be created. Fitzhorn assigned student Mike Senger to the reconstruction task and student Shon Cook to the construction of the front and rear suspensions in the computer program ADAMS 2003, using the regular mechanical suspension first, then changing the model to implement the hydraulic suspension. Estimating masses and inertias, he was to get a working suspension setup constructed, able to produce accurate test results.

This project was an incredible chance for the University to work with a $100,000, one-of-a-kind racecar, the freedom to work independently and explore unique ideas and plans, and the feeling of accomplishment gained from completing the off-car mount of the suspension. While it would have been even better to actually test the suspension and more specifically the anti-roll system, it was challenging and rewarding to do this much.

The progress made paved the way for other students, under the direction of Dr. Patrick Fitzhorn, to work with the suspension. Their tasks included creating the filling and bleeding protocol, testing the function of the suspension and fixing any problems, and also mounting the suspension on the vehicle. And so, instead of becoming the reference in Formula 3 cars for the 21st century, the S-2000 has simply become a research tool in the hands of some very fortunate college students.

Population: 1

- Engineered with the latest CAD/CAM technology
- Full composite chassis manufactured for ultimate rigidity
- Oversized cockpit accomodates drivers of all porportions
- Unparalleled safety features added for driver protection
- Suspension geometry created to maximize performance
- Aerodynamics generated by advanced flow management techniques
- ACRL Spec wing fully integrated using CFD analysis

Crew/passengers: 1

Main sources:
- Motor Sport
- The Auto Channel
- Construction of the Alan Clarinval S22 Racecar Suspension
- Reverse Engineering of the S22 Racecar

The CS22 during tests. Original front wheel display is obvious.

The Colorado State University Motorsports Engineers display the S22 development race car at the 2005 Engineering Days in the Lory StudentCenter Plaza, April 15, 2005.

The S22 on display at the same venue with the hood removed.