Automobile Frames And The Safety Muffler

I have come to believe that virtually no one should ever die in a car accident. Of course, we have heard this before. Students nearing driving age are inevitably given some kind of lecture in school about driver safety, usually with accompanying slides or filmstrips about the horror of auto accidents. There is usually some similar class that would-be drivers have to sit through and in many areas, those caught speeding or committing other traffic violations have the option of spending a beautiful Saturday afternoon in a classroom listening to such a lecture.

But really, no one should die in a car wreck. Not long ago, five newly-graduated girls were killed in such a wreck in the general area where I live and a few months back, there was a similarly unfortunate tragedy east of Toronto. I began wondering what could be done besides lecturing people to drive carefully.

The construction of modern cars began over a century ago. Buildings had been built around steel frames for a few decades and cars were constructed on the same concept, as if a car was a miniature building that moves. No matter how much progress has been made in the design of cars, the basic frame around which the car is built uses the same essential concept today as a hundred years ago.

The trouble is that cars get into crashes while buildings don't. When automakers try to make cars safer based on structure, it is with an "arms race" concept, making the car more sturdy so that it's passengers are safer but those in the other car are not. As much as improvements are made to cars, I find that the basic design is the result of tradition-bound, grooved-in thinking. In contrast to the design of the body or the power of the engine, the design of the auto frame is utterly devoid of glamor or sales potential.

There are springs on the car, whether coil or leaf springs, and shock absorbers (dampers in Britain) to make the ride smoother for the passengers. Why can't the entire frame of the car be a spring? The passenger cage can be solidly built and sorrounded by a body made of springs to absorb the impact of any crash. The idea is to spread the force of impact around.

When I was a boy, there was a pond nearby that would freeze over in the winter. One day, I could not walk on the ice because it would break but I noticed that if I put a board that I found on the ice, I could walk on the board and the ice would not break. The reason is simply that the board spread my weight over a larger area of ice instead of being concentrated in one place.

The same can be done on cars, dissipating the force of an impact over the entire vehicle rather that having it concentrated in one spot. There is a company that makes giant shock absorbers to protect buildings and bridges from earthquakes. The force of an auto crash is virtually nothing compared to that of an earthquake on a building. If this can be done, then why can't the entire body of a car be designed to absorb impact?

The car could be designed to bounce back one or two meters in a head-on crash while heavy-duty rear brakes absorb much of the force of impact. A joint could be built into the steering column so that it would not be pushed into the driver and head rests could be built into all seats to prevent whiplash while the impact of the crash is absorbed.

There was a tragic recent fiery car crash in Ontario and I recalled an idea that I had first thought of after a similar crash some time previously. A lot of progress has been made in recent years, such as airbags that inflate and protect passengers upon the impact of a collision.

There is more progress that can be made in minimizing the chance of a fire breaking out following a collision. What happens is that the muffler and catalytic converter on the underside of a car gets hot so that it ignites volatile fuel which may spill onto it during a collision. This happens most often in pile-ups, when cars are likely to be struck near the fuel tank.

I recall someone once parking over some leaves, and the hot catalytic converter set the leaves ablaze. There is a limited amount of fuel that is actually in the engine, at any given time, so the fuel in the fuel tank itself is most likely to feed a fire.

The muffler is so-called because it muffles noise from the engine as the hot exhaust passes through it, as the catalytic converter neutralizes dangerous chemical compounds in the exhaust. But in doing so, both retain a lot of heat themselves which can ignite a fire if fuel spills in a crash.

Notice that such car fires occur much less frequently in winter, or during rain. This is not because cold air stops the fuel from igniting. If this were the case, the car would not even start. Fuel is actually made more volatile in the winter.

Neither does rain stop the fuel from igniting. Gasoline (petrol) is lighter than water, so that it floats, and water will just spread it over a wider area. The reason is that the cold winter air or the splashing water prevents the muffler and catalytic converter of the car from getting hot enough to ignite leaked fuel during a crash.

The reason that the muffler and catalytic converter of a vehicle gets hot enough to ignite spilled fuel is due to the way a car is designed. In the effort to make the car as aerodynamic as possible, reducing air friction so that the car moves more efficiently, the muffler-catalytic converter system is tucked up away from the stream of air that flows underneath the car as it is moving.

But this is what results in the muffler and catalytic converter building up so much heat. The engine is cooled by air flowing over the radiator, so that it does not get too hot. Why don't we design cars with the muffler and catalytic converter placed so that there is a steady stream of air all around them as the car is in motion? There could even be a screen placed to deflect air onto the parts that get hot. Another possibility is cooling fins on the muffler and catalytic converter.

This would make the car a little bit less aerodynamic, but it would be worth it in reducing car fires following collisions.