HIGH-TECH at the crossing - development of advanced railroad crossing equipment

Railway Age, Oct 1, 1998 by Luther S. Miller

As R&D teams press their search for safer crossings, one demonstration project stands out: A four-quadrant gate system that can warn approaching locomotives of crossing obstructions.

Giant strides have been made in grade crossing safety in recent years, thanks to the enormously successful public-education initiatives of Operation Lifesaver, increasingly sophisticated and reliable warning systems, and a growing crackdown on violators.

Between 1992 and 1997, crossing accidents dropped by more than 21%, fatalities were down more than 20%, and injuries dipped 22%. Because all of this came about at a time when rising railroad traffic was increasing exposure at crossings, the accident rate per million train-miles dropped by an extraordinary 31% in a six-year period.

But if the grade crossing picture has improved dramatically, it is still, as many a nightly-news film clip reminds us, a grisly one.

In this year's first six months, accidents were down 8.8% from the same period last year, fatalities were down 1%, and there were 8.15% fewer injuries-but 1,703 crossing accidents still claimed 217 lives and caused 630 injuries.

That's why many millions of dollars continue to be pumped into research and demonstration projects aimed at further reducing the frequency of crossing accidents (there's now one every 100 minutes).

LEARNING CURVE AT SCHOOL STREET

The return of high speed passenger trains to the rails has led to a number of high-tech crossing-safety experiments across the country. The newest and the highest-tech of these is an enhanced four-quadrant gate system that went into operation in midsummer at the School Street Crossing in Mystic, Conn. Milepost 131.3 in Amtrak's Northeast Corridor.

There are 14 at-grade crossings within a single 20-mile segment of the Corridor, and 12 are in Connecticut. Some will be eliminated. Others won't be, says the Federal Railroad Administration, either because of environmental issues or a community's desire to preserve vehicular access at grade. One of these is the School Street Crossing.

School Street provides the only road access to a 27-acre suburban commercial/residential area and marina. Seventeen daily trains now cross School Street at speeds up to 70 mph; as many as 52, including Amtrak's new high speed trainsets, will be using the crossing by 2010. Up to 900 vehicles a day cross the tracks at School Street, many of them with boat trailers. In the past, the crossing has been protected by a system of flashing lights, bells, and gates limiting access for around 35 seconds.

Four-quadrant gates are not new. What's different about the four-quadrant gate system at Mystic is that it's enhanced by a crossing-to-locomotive cab warning system that alerts engineers to slow down or stop if there is a disabled vehicle or other obstruction in the crossing.

As described by FRA: "Vehicle detection loops were installed by cutting a 3/8-inch notch, several inches deep, in the street between all gates and the near gate on each travel lane. Vehicle detection loops were also installed between Track No. 1 and Track No. 2, bringing the total to six loops." Test loops verify that the detection loops are working.

This addresses a major concern of safety officials with respect to four-quadrant gates:

"Four-quadrant gates prevent motorists from going around downed gates, but can become a trap for those who get by the entrance gate and are stopped by the exit gate," points out FRA, which has contributed $800,000 toward the $1 million cost of the Mystic demonstration (the State of Connecticut kicked in the rest). "Vehicle detection and gatedown indication has been incorporated in cab signals to prevent this from happening. The end result is the School Street crossing is treated as an interlocked junction of two rights-of-way."

A number of suppliers arc involved in the Mystic test. Union Switch & Signal supplied the MicroLok Plus interlocking control and the Model 95 gate mechanisms, Harmon Industries supplied the track circuits, Rockwell the Vigilant highway crossing monitor, and Reno R&E the vehicle detection system.

The concept for the in-cab, at-grade crossing advance warning system was developed by a team of Amtrak, FRA, Connecticut DOT, and private sector engineers.

The Mystic system went into operation on July 20, though it was not officially dedicated until Aug. 26 when FRA Administrator Jolene M. Molitoris characterized it as "an excellent opportunity to test and study how state-of-the-art technology will enable the high speed trains of the 21st Century to operate efficiently and safely."

In mid-September the Connecticut DOT's project manager, Stephen Szegedy, was able to report, "It's working beautifully. Interfacing a loop detector into the cab signal system has never been tried before, but there have been no glitches. Our goal has been a 60-second dwell time for motorists, and we've got it down in the very low 60s."

TAR HEEL TESTS CONTINUE

Four-quadrant gates are also part of another ERA demonstration, North Carolina's "Sealed Corridor" project, but because this is not cab-signaled territory the kind of crossing-to-cab warning system used in Connecticut is not applicable.