Armstrongs is not a lone voice. Apples Wozniak told a forum in America earlier this year about what he believes to be a software problem in his Toyota Prius, claiming it goes wild, but only under certain conditions of cruise control. He also claims to be able to repeat the condition safely.
Seven years ago the late American journalist James Castelli wrote a book on sudden acceleration in conjunction with Carl Nash, then professor of engineering at George Washington University, Clarence Ditlow, director of the US Centre for Auto Safety at the time, and Michael Pecht, who was chair professor from the University of Maryland. Entitled Sudden Acceleration: the Myth of Driver Error, it is a study of unintended acceleration cases going back more than 20 years, and of the NHTSAs failure at that time to recognise and deal with the problem.
In the preface, the authors say: The myth that sudden unintended acceleration incidents are all due to driver error has cost lives. It adds: Electronic systems have made highly effective engine emissions controls and safety systems possible. Hopefully, car makers will also use the most sophisticated approaches to ensure the safety and reliability of automotive electronics
If the focus has been on cases in America, thats because large-engined rear-wheel-drive cars with automatic gearboxes and cruise control are more prone to sudden acceleration and harder to stop, says Armstrong. Europeans tend to drive smaller front-drive cars with manual gearboxes, and make less use of cruise control, if fitted. In Europe there are also many more diesels than in the US, and diesels dont have an electronically controlled throttle valve.
More people drive than fly, so why do aircraft have multiple safety systems, but cars don't?**Potential for new intermittent faults**
However, there is no room for complacency. As Castelli said in the summary to his book: Every new automotive design carries the potential for new intermittent faults, some of which may result in sudden acceleration. The increasing complexity of cars, shared electrical architectures and the economic problems of the car industry are all potential concerns, claimed Castelli. There is also a risk as cars get older. Nothing in electronics gets better with age, says Armstrong.
However, he also claims that the dangers can be significantly reduced if not eliminated altogether with proper shielding and back-up systems for the electronics. We know how to do it. Its not black magic and it need not necessarily be expensive, he says.
Globally, the car industry continues to argue that its testing procedures are extensive enough to find any potential electronic glitches and that there is no case to answer. Britains Society of Motor Manufacturers and Traders says: Supported by real-world examples from the billions of vehicles sold around the world, plus comprehensive scientific testing of electronics systems under a significant range of conditions, no examples have been found of unintended acceleration due to system defects.
What Car? says
Experts cannot prove definitively that cars are accelerating on their own because of electronic faults, any more than the car industry can prove that they are not. Surely, though, cars deserve electronics systems every bit as robust as those in aircraft? They cover far more passenger miles in much closer proximity, and their drivers are usually less skilled than airline pilots. Safety should not have a price.