May 7, 2009
|North American bird-strike risk is rising, and consensus is growing that mitigating it depends on a mix of new procedures to make take-offs safer plus new technologies to beef up aircraft and make bird flocks easier to see and avoid.
Air traffic worldwide has grown nearly 5%, on average, each year for the past two decades. And a top U.S. bird-strike researcher notes that populations of some of the biggest birds in North America — eight pounds each or more — are exploding thanks to aggressive environmental and conservation efforts.
Statistically speaking, growing North American bird populations and increasing air traffic can only mean one thing: increasing risk of collisions between birds and aircraft.
Citing those growing populations, the answer lies in revisiting airworthiness standards and pressing for new technology, says Richard A. Dolbeer, with the U.S. Agriculture Dept.’s Animal and Plant Health Inspection Service (APHIS), Wildlife Services.
Presenting at AVIATION WEEK’s Birdstrike Prevention Forum this week in Chicago, Dolbeer argued for five steps: reevaluating airworthiness standards; focusing wildlife hazard mitigation efforts in and around the airport; evaluating and implementing bird-detecting radar; keeping departure airspeeds under 250 knots below 10,000 feet, and; enhancing aircraft visibility and detectability by birds.
Some of these efforts are already underway. Electronics advances now allow low-cost integration of off-the-shelf radar technologies, like those used for small pleasure boats, with fast computers and processors to create low-cost automated radar installations. FAA’s Ryan E. King, who leads a bird-strike project for FAA’s Airport Technology R&D Team, reported at the Chicago meeting that test radars are in place for evaluation at Seattle Tacoma (SEA), Chicago O’Hare (ORD) and JFK International (JFK), and another installation is under consideration at Dallas-Fort Worth (DFW).
Manufacturers say a typical X-band installation can detect small birds reliably up to two miles away on either side of the emitter, as well as 5,000 feet upwards from the radar. Recently, engineers have started incorporating X-band and S-band emitters in the same unit, using the X-band for vertical scanning and the S-band for horizontal searches, giving a more accurate picture of bird activity in the area under surveillance. In this kind of setup, small birds can be found two to three miles away from the installation and some 5,000 feet above it.
FAA is studying products from four vendors: the Accipter Avian Radar Detection System, made by Sicom Systems, Ltd.’s Accipter Radar Technologies unit, Merlin, made by DeTect, Inc., GeoMarine, Inc.’s Mars Avian Radar Detection System, and the ROBINLite system developed by a Dutch government-backed R&D arm.
Mont Smith, the U.S. Air Transport Association’s safety director, echoed Dolbeer’s call for slower departures, which minimize the effects of a collision between large birds and aircraft in the one flight regime — take-off — blamed for more than 90% of the total hull-loss accidents recorded since 1968 involving bird-strikes. But he noted that today’s airspace management strategies don’t account for such a procedure.