Mike Stevens | Feb 19, 2009

Programs on TV that I put in the 'weirdly interesting' category are the Greatest Police Chases-style shows.

These shows with high-speed pursuits, spinning cars and hapless perpetrators have always struck me as being akin to comic book violence. There is a voyeuristic un-reality about it: where there's action, sirens, and people get hurt, but not really.

Blues Brothers Mall Chase

It is amusing, in a cringe-inducing way, watching these prime-time nut-jobs at work.

There is, of course, a more serious and deadly issue behind it.

Too many police pursuits end up with one of the participants crashing, too often with fatal consequences; while some end up with the offenders simply getting away.

NSW statistics show that in the eight decades from 1926, nearly double the amount of people have died from police car chases than from police shootings (99 deaths to 49 deaths as at December 2004).

Regrettably, many of those killed are the innocent occupants of other cars, or pedestrians, as in the case of 13-year-old Caitlin Hanrick from Redcliffe, Queensland, who was hit by a car being chased by police as she crossed a road in 2006.

In fact, around 10 percent of police pursuits result in a crash, with a smaller percentage resulting in the arrest of offenders (Sydney Morning Herald).

That's a lot of risk for little reward.

Police Pursuit Crash

In recent years, police have turned to tyre spikes laid across the road to halt the progress of offending 'runners'.

The problem is that destroying a suspect's tyres can send them careering out of control. Or, because the mat of spikes sitting on the road is usually quite visible, offenders will often swerve at high speed to try to avoid them.

In NSW in 2001, a policeman was killed when an offender swerved across two lanes to avoid road spikes and hit the waiting police officer - a Senior Constable Affleck - who had moments earlier placed the spikes across the road.

(The increased use of run-flat tyres may also pose some problems in the future for this method of intervention.)

If the whole point is to avoid crashing and increase safety for officers and other road users, destroying the tyres of a car travelling at high speed might not be the best idea.

Stinger Tyre Spikes

Clearly some of the contractors for the USA's Department of Homeland Security had been watching a few movies and reading some comic books, because they have come up with the SQUID, or Safe Quick Undercarriage Immobilization Device.

Now if you've seen Jerry Bruckheimer's Pirates of the Carribean series, you'll know of the legendary sea monster called the Kraken - a giant squid that surfaces from the deep, and wraps its tentacles around ships to drag them to their doom. On the same comic book-style theme, you might also ponder for a moment Spiderman's ability to shoot sticky webs to attach to, and drag objects to a halt, like... say... a train.

If you can wrap your head around those images - the Kraken, and Spiderman's near indestructible web - you might then be able to also wrap your head around how the Safe Quick Undercarriage Immobilization Device works. Here are some pictures to help:

spider-mankrakenThis is essentially the basis of how the SQUID works. It has tentacles to ensnare, and then sticky webbing to gradually capture a vehicle that falls into its grasp.

It works like this: a flat disc, about half a metre across, is put onto the road with the operator standing a reasonable distance away. When 'the runner' approaches, the operator activates the device which unfurls several barbed straps onto the road (hopefully too late for the suspect to take evasive action).

When they drive over these tentacles, the barbs bite into the tyre and the tentacles are flicked up into the suspension and axles. At the same time, a sensor in the device responds to the engine heat and instantaneously fires sticky tendrils under the car which foul the drive-shaft and axles.

All things going to plan, things get wrapped up in a mass of sticky webbing, twisting round the moving parts and dragging the car to a halt. (And pulling up the car slowly rather than suddenly sending the vehicle into an uncontrolled skid.)

The main benefit of the system is that it is easy to deploy. The base disc is about the size of a garbage can lid, and easily carried and removed.

Should the suspect veer off early the operator doesn't need to deploy the unit allowing other traffic using the road to pass harmlessly over it.

At the moment it is still a prototype. The device has successfully pulled up a small pickup truck from around 60km/h during testing. The goal is to have the unit being able to pull up a big SUV, like a Ford F150, from 200km/hr.

[ DHS ]

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