New tire deflating device obviates need for police car chases

Published 24 August 2007

Car-chasing a fleeing criminal at high speeds is dangerous to the police and to innocent bystanders; a Wisconsin company, with help from NASA, designs a “throwable” tire deflating device allowing law enforcement to force fleeing car to stop without giving chase

There are too many stories about people — often innocent people — being killed during police car chaces. Both the fleeing criminal and the chasing police cars go very fast, and accidents are bound to happen. Now, what if, instead of chasing a car, a metal strip with spkies would be thrown on the road to puncture the fleeing car’s tires and bring it to a stop, obviating the need for a risky chase? We encounter stationary tire deflation devices (TDDs), which is a strip which contains embedded metal spikes, at the exits of city parking garages, where they are placed to prevent drivers from leaving the garage without paying. TDDs, however, may also be thrown over the road in front of a speeding vehicle, deflating the tires and forcing it to stop. The device allows law enforcement stop a speeding vehicle safely, often without the need of a dangerous high-speed pursuit. The designers of the TDD had a problem: How to keep spikes attached to the strip unless a tire runs over them. In reality, spikes that did not puncture the tires were often knocked loose by fleeing cars and trucks, scattering across the road and creating a potential problem for other motorists, plus a clean-up nuisance for police officers.

NASA teamed with Brookfield, Wisconsin-based Phoenix International to develop a better engineering solution to keep the unused spikes in place while still allowing the strip to have puncture power. NASA’s Plum Brook Station’s facilities tested the MagnumSpike! tire deflation device, manufactured and marketed by Phoenix. Researchers concluded that the retention clip on the strip could not reliably hold all of the spikes in place. NASA engineers worked to improve the performance of the retention clip, and the results were passed to a Cleveland-based engineering firm as part of additional testing. Based on the analysis, NASA and the engineering firm recommended a new pin shear method, which Phoenix used to develop a new, friction-free retain-release clip. Since then, MagnumSpike! has been field tested and proven capable of swiftly and safely stop everything from eighteen-wheelers to compact vehicles — even those with self-sealing and run-flat tires. The company says the technology has a 100 percent safety record and 100 percent take-down record in deflating all tires that have come across its path. In some cases, fleeing suspects have seen the spike strip, skidded to a halt, and simply surrendered. Now that’s crime prevention.