Adding a spoiler is a great way to improve the appearance and aerodynamics of a vehicle, but could it do more harm than good? A spoiler is a wing or aerofoil attached to the back of a vehicle and serves to break up the airstream and increase wake turbulence which promotes downforce (or increases drag, depending on the speed the vehicle is travelling). Spoilers come in many shapes and sizes, from subtle to extravagant, and the majority are designed as bolt-on styling gimmicks that serve no aerodynamic purpose, with very few notable exceptions.
A recent study by Dr. Aonghus McNabola at Trinity College in Dublin suggests that rear spoilers of all sizes do serve a dynamic purpose—one that might induce sickness and carbon monoxide poisoning. His research found that rear spoilers set at certain angles concentrate plumes of tailpipe pollution at the head height of pedestrians, cyclists, and motorists who might follow in the car’s wake.
The story, released in The New York Times, noted that McNabola’s research was based on scientific modeling, using five different spoiler setups, while taking into consideration variable wind and vehicle speeds.
Research found that the spoiler configuration with the greatest angle of the five spoiler setups showed the largest concentrations of benzene (harmful exhaust pollutant) of over 40 percent at human head height, while one of the flat rear spoiler designs tested actually decreased those same concentrations by 18 percent.
Research also found that any spoiler with angles greater than zero could lead to the overall exposure of someone cycling, walking, or even driving behind a car. He states that the spoiler’s placement on the trunk is not as critical as its angle, and that the spoiler won’t change the amount of pollution, just the concentration. McNabola’s final conclusion was that automakers could use his information to design spoilers to reduce their impact on air pollution in the near future.
Until the good doctor’s research prompts a worldwide ban on spoilers to create a greener earth, I urge all pedestrians and bicycle riders to wear respirators, because my pollution-inducing Voltex GT Wing isn’t coming off anytime soon!