Tracking all Movement: MKE first with ASDE-X system

Fueling/Line

Tracking
All Movement

By Jodi Richards, Associate Editor

MKE first with ASDE-X system
Milwaukee's General Mitchell International Airport (MKE) air traffic control is using an advance in technology allowing air traffic controllers to better monitor activity on the runway and taxiway. The Federal Aviation Administration-funded program involves utilization of ASDE-X, airport surface detection equipment Model X, from Syracuse, NY-based Sensis Corporation. Over the next three years, the system will be deployed to at least 21 airports across the U.S. with the intent of reducing runway incursions.

Marc Viggiano, Sensis Corporation president of air traffic systems division, describes a runway incursion as a loss of separation between two aircraft, or an aircraft and a vehicle or person. "And it's not surprising that as airports get busier, and we try to get more aircraft in and out of airports, keeping them apart on the ground is a problem," he says.

Sensis Corporation has been in business for some 19 years. It has two divisions: air defense systems and civilian air traffic control systems. "The defense business is really how the company was started," he explains. "We started as experts in radar and systems integration and then applied that technology to the civilian world."

According to Viggiano, "The ASDE-X program is an FAA program that's primarily focused on safety, although the technology does have a number of capacity and efficiency benefits."

Applying The Technology
ASDE-X combines multiple sensors to gather data. It then takes that data and fuses it together for display on a color screen in the tower. "It's an integrated system," says Viggiano. "Instead of just relying on a single radar, [ASDE-X] uses a radar, a transponder multilateration sensor, as well as an ASDE (airport surface detection equipment) sensor and the existing airport radar. It takes all those sources and fuses them together to make sure that you can do a good job of reliably detecting the aircraft and also providing a positive identification by its flight ID."

The ASDE-X system is comprised of several pieces of hardware and software. "The sensors themselves that actually detect the aircraft are the most visible, external part of the system," says Viggiano. "The SMR (surface movement radar) antenna is the part of the system that detects the aircraft. It will see somebody whether your transponder is turned on or not. It will even see unequipped snowplows, small GA aircraft, and large animals." This antenna is mounted on top of the control tower, or possibly on a stand-alone tower. It stands some one-foot tall, is 24 feet in length, and spins at 60 rotations per minute.

The transponder multilateration is another piece, which is a cooperative surveillance system that provides position and identification of all transponder equipped aircraft. Says Viggiano, "They are small cabinets, that can be mounted outdoors, the size of a small dormitory refrigerator, and a little antenna that looks like a cell tower antenna, which doesn't move. It's stationary and typically mounted on an existing structure." Generally, he adds, there are about eight of those sprinkled around the airport.

Data from the sensors are then fed back over a communications system, typically telephone lines or existing networks, explains Viggiano. The communications are fed back to the equipment room, which is usually in the control tower. All the processing takes place there, while the surface movement radar tower can be located several kilometers from the control tower.

According to Viggiano, the radar is only looking at the movement areas, - runways and taxiways. "So if you have a snowplow on the runway, the radar will pick it up, however it won't tell you what it is. It will be a blob." Although, an external antenna, called a Veelo, can be mounted to a vehicle. "For example, if you want to keep track of your snowplows, fire trucks, or tugs, you put one of these units on it and it will show up on the same [ASDE-X] system - not only where it is, but who it is."

The number of sensors at a given airport depends on the physical layout of the airport, Viggiano explains. "It's a function of its actual geometry - not just how big it is, but also where the runways are." A site survey is done to determine the needs and appropriate locations for the sensors.