Embry-Riddle launches ADS-B technology trial

 - October 4, 2007, 5:23 AM

By this summer, Embry-Riddle Aeronautical University expects that the flight-training fleets at its Daytona Beach, Fla., and Prescott, Ariz. campuses will be fully equipped with automatic dependent surveillance-broadcast (ADS-B) avionics. Between 40 and 50 aircraft–primarily Cessna 172s and Piper Seminoles–at each location will receive ADS-B installations.

The university’s move is a major initiative under the FAA’s Safe Flight 21 program (AIN, April, page 75) and is coupled with the agency’s provision of Sensis-built ADS-B ground stations, installations of which are currently under way.

On a recent visit to Embry-Riddle’s Prescott campus, AIN was briefed on the project by Sean Jeralds, chair of the flight department. “The three main reasons we want ADS-B,” said Jeralds, “are flight safety, local airspace monitoring and management and to expose our students to the latest aviation technologies.”

Flight training at Prescott is carried out primarily within a 38-mile radius of the airport VOR/DME, and the area is divided, dartboard like, into nine pie-shaped sectors defined by specific radials from the airport VOR/DME. Each sector is between 25 and 45 degrees wide and each has a unique name, such as Cottonwood or Big Spring. And the bull’s-eye of the dartboard is the airport terminal area, extending out over an 11-mile radius from the VOR/DME.

But while that sounds like a lot of airspace, the 40-plus training aircraft fleet has experienced a significant number of near collisions in the past, with some calling for evasive action to avoid contact. Jeralds is confident that the situational awareness of other traffic, something ADS-B will bring, will substantially reduce, and hopefully eliminate, this threat.

One contributing factor to the near-collision incidence is that, at Prescott, coverage from the closest ATC radar–Albuquerque Center’s Seligman, Ariz. facility–is poor, extending downward to just below 2,000 feet agl due to its distance and intervening high ground. This is in contrast with the much lower-level radar coverage at Embry-Riddle’s Daytona Beach campus.

Because of this, the Prescott staff keeps close tabs on the movements of the training fleet, and a large local map, overlaid with the dartboard-like training sectors and central terminal area, covers one part of the dispatch office wall.

Aircraft-shaped magnetic markers, with individual tail numbers, show the assigned sector location of each aircraft for airspace-management assessment, supported by computer flight-plan data.

When ADS-B becomes fully operational, the big dartboard will be supplanted by a large electronic display, presenting moving aircraft symbols, each tagged with its individual ID, altitude and other quick-reference data. This way, students on solo missions will always have an instructor looking over their shoulders quietly from afar.

Valuable Exposure
But while Embry-Riddle is eager to give students early exposure to such advanced technology, in preparation for careers in corporate or airline flying, basic airmanship is still a key part of the curriculum. Therefore, while every aircraft will carry a comprehensive Garmin avionics suite with navcom, transponder and MX-20 display with airways, topographic, terrain warning and ADS-B situational awareness of other aircraft, it is planned that solo students will be given a plug-in card to limit the display to aircraft-only ADS-B data.

The university wants students to develop their own situational awareness skills regarding their outside surroundings, without relying on the magic boxes. However, should the student get into any difficulty, he or she can override the plug-in card and have full use of the ADS-B avionics.

Besides these features, the aircraft’s Garmin GDL-90 ADS-B unit will display flight and traffic information on the MX-20, uplinked from any of the ground stations that will cover ERAU’s training areas. The flight information service-broadcast (FIS-B) will uplink weather, notams, TFR updates and other information. The traffic information service-broadcast (TIS-B) will uplink the locations of non-ADS-B-equipped aircraft in the vicinity, which the aircraft’s avionics would not automatically “see.” TIS-B will be a key safety factor during the international transition to the future worldwide ADS-B environment.

Another valuable benefit from ADS-B will be the ability to replay all or any part of a flight after landing. In the past, this has always been on a flight instructor’s wish list,
and ADS-B will now make it a reality. An interesting variant of this technique will also be featured in ground training, where all the campus flight simulators will also incorporate ADS-B displays, allowing students to see, interpret and learn from potential virtual midairs in a completely safe environment.