Ford Pinto design engineering issues

Quick notes

-The Ford Pinto was an automotive safety engineering failure.

-Repositioning the fuel tank and adding a rubber bladder could have prevented many injuries and deaths.

The Ford Pinto became a fiery hotbed of flames when rear-ended at a relatively low speed of 25 MPH and higher. But why exactly was this?

Fuel tank position and location

The Ford Pinto fuel tank was located in front of the rear bumper, behind the rear axle. Common for subcompacts at that time. Not only did the position make it vulnerable to direct impact damage, which when you think of how combustible gasoline actually is makes the design position just bonkers, but the Pinto was specifically designed to be light so the rear end was prone to crumpling upon lower speed impact.

The Ford Pinto became a fiery hotbed of flames when rear-ended at a relatively low speed of 25 MPH and higher.

In addition to the Pinto’s propensity to crumple when rear-ended at low speeds, the position of the fuel tank made it vulnerable to puncture by bolts from nearby brackets. These bolts were poorly placed and protruded directly beside the tank. The placement of these bolts was catastrophic in terms of safety design.

Most rear-end collisions resulting in a fire were primarily as a result of the puncturing of the fuel tank. Once the tank was punctured it’s estimated that it took less than a minute for the fuel tank to empty and spill out, leading to fire. The likelihood of the fuel tank being punctured or otherwise becoming compromised and leaking fuel was exacerbated by the actual design of the fuel tank.

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Fuel tank design and materials

In addition to the awkward position of the fuel tank, which was positioned just so in order to maximize rear seating space and storage, there was an issue with the actual design and material of the fuel tank itself. The fuel tank had a long filler neck and the body was comprised of thin sheet metal.

When the Pinto was hit from behind the impact often caused the filler neck to split from the sheet metal tank. The walls of the fuel tank itself have been described as ‘exceptionally thin’ meaning it was very easy for the tank body to be punctured. Coupled with the fact that there was no built-in protection for the fuel tank itself, nor a lining of any sort for the fuel tank, it made the possibility of the fuel tank being punctured or ruptured upon rear impact VERY high.

Most rear-end collisions resulting in fire involving the Ford Pinto were primarily as a result of the puncturing of the fuel tank.

Ford at the time owned the patent to a better-designed fuel tank. However, the Ford Pinto was in the late stages of the design development and Ford determined that it would be too costly and time-consuming to retool the plants in order to make the suggested safety changes. They wanted to bring the Pinto quickly to the market.

Ford Pinto fire safety solutions

There were solutions to these rear impact fire problems as we’ve since found out. Ford just decided at the time that they did not want to spend the money to implement them. One solution was to move the location of the fuel tank from directly behind the rear bumper. An obvious solution.

Protections could have also been put in place to shield the fuel tank from any direct impact damage. The protruding bolts being moved would have likely greatly improved the Pinto’s safety.

Another solution was to change the design of the fuel tank itself, including the possible inclusion of a fuel tank bladder to prevent fuel spillage if the tank was punctured. Ford already owned the patent for a safer fuel tank design they just did not want to incur the cost of factory retooling that late in the production stage when they were in such a rush to get the Pinto to the market.

Overall, Ford chose profit over safety and the value of human life and it cost them greatly for years.

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