August 10, 2012
En Route Automation Modernization
En Route Automation Modernization (ERAM) is a system that is planned to replace the old en route air traffic control (ATC) automation system. The old system consists of the Host Computer System (HCS), The Display System Replacement (DSR), and the User Request Evaluation Tool (URET). Today those three systems are used at 20 ATC centers in the continental United States. ERAM is being made to provide a more safe and efficient ATC service. ERAM changes are intended to benefit controllers by increasing their efficiency, improving their situational awareness and decision making, reducing their workload, or reducing the frequency or impact of mistakes (Allendoefer, 2006, pp.1). However it may be possible that there will be some unintended negative affect on the controllers.
To try and make ERAM a more safe and proficient system there are a few main areas that will be changed from the old system. The main changes are listed as followed:
Backup and redundancy capabilities of ERAM
Areas of Interest (AOI)
User interface (UI)
In the legacy system, a failure of the HCS forces controllers to use the backup system with reduced capabilities, which reduces operational efficiency (Allendoefer, 2006, pp.2). Depending on which facility you are taking about, the backup system is either the Enhanced Direct Access Radar Channel (EDARC) or the Enhanced Backup Surveillance (EBUS). EDARC has fewer functions than the HCS in the flight data processing and safety alert areas. EBUS is a more up to date backup system than the EDARC but still does not have the full capability as the HCS. By the time ERAM is deployed, EBUS will have replaced EDARC at all ATC centers (Allendoefer, 2006, pp.6). ERAM is equipped with a full function redundant backup system that is equivalent to the primary. Having this redundant backup system is intended to reduce the negative effects in the event of an equipment outage.
ERAM has two equivalent parallel channels called Channel A and Channel B. Both of the channels can be used as the main (active), backup, or other modes used by the Technical Operations (TechOps) personnel. The active channel is the channel used by the controllers while they are controlling traffic. The active channel receives information from all of the external interfaces and then sends that information to the backup channel. The backup channel does receive some information directly from some external interfaces and conducts flight data and weather processing independent from the active channel. In normal situations when synchronization is working correctly both the channels will have the same data. Unlike the legacy system, the backup channel is fully functional and controllers should experience no loss of functionality or efficiency when switched to the backup channel and no corresponding increase in workload (Allendoefer, 2006, pp.6).
If there is a problem with one of the channels there will be an alert prompted on the screen. If one of the channels fails TechOps will switch to the backup channel from one of the Monitor and control positions. The active channel is indicated on the controller console along with the status of both channels. The controller has the power to switch between channels using a keyboard entry. TechOps, the Air Traffic Supervisors, and the controllers will verbally coordinate channel switchovers as needed.
The second major change is the Areas of Interest (AOI). In the HCS controllers don’t have all the information of the aircraft inbound to the ARTCC until it gets to the facility boundary. A controller that is receiving a handoff from another facility can only see limited data blocks (altitude and beacon code) for flights in the adjacent facility. Once an inter-facility message is sent, the controller will be able to see the full data block.
But there are many circumstances in which it would...