| ATLAS F1 Volume 7, Issue 8 | |||
| Helping Hans | |||
| by Ross Stonefeld, U.S.A. | |||
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NASCAR legend Dale Earnhardt's death last weekend, at the final corner of the Daytona 500 race, reintroduced the debate over the drivers' safety devices, primarily those that could prevent head and neck injuries. The most commonly mentioned term in the past few days was 'HANS'. What is this device, and how could it save lives in motor racing, not least of all in Formula One? Ross Stonefeld provides the background
Simply put, the HANS device is as its initials stand for: Head and Neck Support. It is designed to prevent violent movement of the head and neck, which often has fatal consequences.
HANS was invented by Dr. Robert Hubbard, a Professor of the College of Engineering at Michigan State University, in conjunction with his brother-in-law, racer Jim Downing. Their goal was to reduce the potential of serious and fatal injures resulting from violent movement of the unrestrained head.
The system features a collar and yoke constructed of carbon fibre and Kevlar composites. The device extends from front to rear as it sits on the shoulders and is connected to the helmet by 2-3 flexible tethers which allow the minimum necessary head movement to drive a racing car.
Following comprehensive testing at Wayne State University, the support of General Motors, and race use by Downing, the first unit went on sale in 1991.
In October of 1996, a joint venture comprising of McLaren International, Mercedes-Benz, and the FIA, was created to research a driver restraint system for head-on and oblique frontal impacts, with a crash angle of up to 30°.
DaimlerBenz contracted Hubbard/Downing, Inc. for joint testing and development to make the HANS device suitable for Formula One competition. Initial tests - run in a Formula 3000 monocoque specified to 1998 Formula One cockpit regulations - proved successful, and in April of 2000 at the San Marino Grand Prix in Imola the final reports were released and with the approval of the FIA Safety Committee, HANS was recommended for use.
"This is a major step forward in the search to introduce ever-improved safety standards in Formula One," Max Mosley, president of the FIA, exclaimed. "It is particularly significant that the research has been carried out jointly with one of world's major car manufacturers. This shows how motor sport is a research medium for the motorcar industry not only for performance, but also for safety."
Mosley's words were also echoed by Jurgen Hubbert, Member of the Board of Management of DaimlerChrysler. "We are happy to take up the suggestion from the FIA of bringing our knowledge and our many years of experience of safety engineering for production vehicles to the HANS project and possibly also other further research projects. We consider this to be a significant contribution towards making the fascinating sport of Formula One even more safe."
McLaren-Mercedes's David Coulthard and Ferrari's Rubens Barrichello tested HANS during the Formula One winter testing season. Development will continue with the aid of improving driver comfort. HANS is strongly recommended for the 2001 season and will become requirement for 2002.
The system of collars and tethers is designed to keep the head and neck in plane with the body in violent impacts. Below are average strengths of the head and neck. The force withstood is dependent on location of impact, strike object size, and bone tissue density amongst other factors.
In a full human form crash test simulating a 40mph dead stop impact utilising the HANS device, neck loading was kept under 130lbs whilst the unrestrained head endured over 1,000lbs
"As soon as your head - which weighs, with the helmet, 13 or 14 pounds - has a sudden acceleration, it stretches your neck," Downing explains. "If it stretches a little too far, you get a neck fracture or a skull fracture at the base of the skull where your head connects to your spine. With HANS on, the head sort of goes forward then back and looks OK. At the same speed with a fully belted dummy, the head smashes into the steering wheel and it's just appalling. The drivers say, 'Wow. That can't be.' In layman terms, keeping your head close to your body is what it's all about with HANS."
The weight of the head and helmet pulling at the neck can be sufficient to fracture the skull. Known as basal skull fracture (hangman's noose analogy), these injuries can often be fatal. Roland Ratzenberger (F1, 1994); Scott Brayton (IRL, 1996); Adam Petty and Kenny Irwin (NASCAR, 2000) - they all suffered basal skull fractures. Greg Moore's horrific crash in the 1999 CART season finale included basal skull fracture, but other head and neck injuries compounded his incident. There is even speculation by experts that Ayrton Senna would have suffered similar fractures, however the official cause of death was listed as shrapnel penetration of the brain.
CART experts under Dr. Terry Trammel used a mathematical simulation of Gonzalo Rodriguez's death in CART practice in Laguna Seca (1999), and based on these results declared that, "HANS would have saved Gonzalo's life" by preventing basalar skull fracture.
Would HANS have saved Dale Earnhardt? Impossible to say, but it certainly would not have made the situation any worse.
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| Ross Stonefeld | © 2007 autosport.com |
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