Not to worry you, as if you haven't already lost enough sleep fretting over the proliferation of radar, but there's some retro-hardware that's of continuing concern for motorists. Like an aging
matinee idol rescued from obscurity, a speed-measuring device from
the Sixties has been freshened up and continues to be distributed with quiet efficiency
among traffic police nationwide. VASCAR Plus, first used in the mid Sixties
and rarely mentioned in the press since its heyday in the Seventies, has
made a quiet comeback over the past 15 years. Police like it because it makes no use of
electromagnetic radio waves and radar detectors offer no defense
against it. Your first warning of a VASCAR trap will likely be a
trooper pulling up behind you with his red lights on.
VASCAR (Visual Average Speed Computer and Recorder) is a
time/distance computer that times a vehicle between two reference
points, measures the distance then computes the average speed. Although
normally mounted in police cruisers, we've also seen it installed on motorcycles and
it's frequently used in aircraft.
In that application, the distance between reference marks painted on the road below is entered by the aircraft operator or observer. Then he simply flips the Time toggle switch on and off, using the internal quartz-crystal timer to clock cars between the
two marks. With time versus distance recorded, the target's average speed is displayed. Then the pilot radios chase cars below (called catch cars in the business) to make the stop and hand out the speeding ticket.
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| The observer enters known distances between
highway reference marks into VASCAR, then uses its stopwatch function
to time cars between marks. Computer then calculates average
speed. |
Few aircraft are used for speed enforcement since they're expensive to buy and operating costs are high. But if you're keen to keep track of aerial speed enforcement, a good UHF/VHF radio scanner lets you eavesdrop on them when they're operating.
VASCAR Plus and its competitor, the Kustom Signals Tracker are most often found in traffic-enforcement cars. Each has an input from the VSS (Vehicle Speed Sensor, the gadget that also drives the speedometer) for distance input and a combined computer/control module
to handle math computations and memory functions. A manual distance input can be used if the officer is using reference marks painted on the road by the highway department, measured precisely and certified as accurate.
The VASCAR Plus control module
has two switches, one for time input, the other for distance, along
with a small three-digit speed display window and thumbwheels for
manual distance inputs. The Tracker, a much newer design, has three windows and a mini-toggle switch for manual distance input.
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| Tracker's windows display (from upper left) average speed, elapsed time and distance. (This one's definitely go-to-jail velocity.) Distance (left toggle switch) and Time (right switch) are primary controls. |
Here's how it works. Assume you're driving down a stretch
of divided Interstate roadway. Coming at you is a state trooper
with VASCAR. As he spots you he'll look for a reference point where
he can begin timing you. Many states paint broad white stripes across
the road for this purpose but if the trooper is in open country
he's unlikely to have these available. So he will improvise and make use
of other landmarks: tar strips, road signs, and shadows across the
road all serve nicely. At night he will use the flash of your headlights
against reflective road signs, median barriers, reflective mileage
markers or even discarded soft drink cans at roadside. As the front
of your car passes his mark the trooper flips on his time switch,
activating the internal timer. As you continue to approach him he
will choose another reference point, wait until you hit the mark
then turn off the timer. Now your elapsed time between the two reference
points is stored in the computer.
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| Large, white marks across highway
mean VASCAR may be lurking, on the ground or in the air. VASCAR
transmits no radio signals for a detector to hear; vigilance
is the only defense. |
The next step is simple. He passes you, U-turns through
the median and drives to the first reference point. Here he turns
on the distance switch, travels to the second point and turns it
off, recording the distance you traveled. The computer handles the
number crunching and displays your average speed to 0.1 mph. The
hardware's accuracy tolerance is plus or minus 1 percent. Since at freeway speeds
the minimum recommended clock is one tenth of a mile, the operator can
miss his marks by a fair distance and still get a clock within a
2-3 percent accuracy window.
Since the operator has to take an active role in using the device,
VASCAR has never been popular with lazy officers. But in the hands
of an aggressive trooper, especially when used from an unmarked
car, VASCAR can be deadly.
Knowing how meeting clocks are done, study up on the others:
Following
Using reference marks as described in the above meeting
clock, the trooper drives behind the target and activates the time/distance
switches. If he is in a marked cruiser he will usually hang well
back and mingle with other traffic to avoid detection. If you suspect
a VASCAR clock the proper response is to quickly slow far below
the limit to lower your average speed. Once late at night on I-70
in Ohio I studied in the mirrors a car that seemed to be keeping
pace although he never approached
closer than half a mile, making it tough to gauge his relative speed
in the darkness.
Knowing that Ohio had VASCAR at the time, I waited until I crested
a hill then moved into the right lane, braking heavily to 45 mph,
continuing at that speed for about a third of a mile, then accelerating
again to 55 as the lights popped over the hill and rapidly approached.
It was a white highway patrol Plymouth. After falling into step
for a while he lost interest and passed me.
Front Clock
Watching you in his mirrors, the trooper will choose marks and
clock you as you approach. By the time you notice you're closing
in on a trooper it's all over.
Roadside clock
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| The pilot may not be able to personally stop
a fleeing violator but his vantage point 1,000 feet in the air
means there's zero chance of escape. |
The trooper paces off a stretch of road, storing that distance
in the computer. Then he parks in a shady, concealed spot and times
cars between his marks. A favored location is around freeway on
ramps. He'll clock you as you come out from under the overpass to
the point where the on ramp merges with the highway, a nice tenth-mile
clock. Look for him parked at the top of the on ramp.
Thirty-eight states use VASCAR, about half of them from aircraft
as well, according to Tom White, national sales manager for Traffic
Safety Systems, marketers of the device. The Maryland State Police
recently installed it on six motorcycles and have been so encouraged
they are planning a dozen more. The biggest users: North Carolina,
Florida, Maryland, Indiana and Wisconsin.
With traffic police increasingly frustrated by detector-equipped
speeders, it's a safe bet VASCAR will increasingly become a part
of the speed enforcement scene, like it or not.
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