Few of us realize the scope of the operations, the technological resources and the number of personnel involved in responding to a major air disaster. The task of locating and retrieving victims and wreckage -- essential in determining probable causes of the crash -- require the coordinated efforts of many civil and military agencies, hundreds of technicians and specialists and the convergence of advanced technologies. Aviation safety often depends on the timeliness and thoroughness with which these operations and subsequent investigations are carried out.

When Alaska Airlines Flight 261, en route from Puerta Vallarta to San Francisco, lost elevator control at 30,000 feet and dove into the sea off the coast of southern California last year, the crash triggered an immediate response from federal, state and local agencies, the military and several private organizations. From the initial search and rescue efforts to the final recovery of victims and aircraft remains, interagency cooperation and the application of advanced technologies such as GIS, GPS, sonar and other remote-sensing systems played a major role in expediting complex operations.

A Grim Task

The crash occurred at about 4:30 p.m. on Monday, Jan. 31. Within minutes, search and rescue helicopters from Point Mugu Naval Air Station were on scene, followed by surface craft from the Channel Islands United States Coast Guard (USCG) Station, commanded by Captain Andy Jones. Jones coordinated the search for survivors by USCG and volunteer vessels, and set up a security zone around the area of floating debris. At about 6 p.m., the smaller USCG craft was relieved by the 82-foot cutter, Point Carrew, from the Eleventh Coast Group, Long Beach.

Because the plane went down in the Channel Islands National Marine Sanctuary (CINMS), one of the many authorities the USCG alerted was the Santa Barbara headquarters of the National Oceanic and Atmospheric Associations CINMS, the agency that protects and manages the resources of the sanctuary. CINMS has an extensive GIS system with multiple data layers of the islands, information on sea conditions and bathymetric data (topography of the ocean bottom) within the sanctuary. Their staff could provide orientation maps and other supporting data.

Although no survivors were found in the immediate area of the crash site, the USCG continued to search the floating debris throughout the night. As many remains as possible had to be recovered and turned over to National Transportation Safety Board (NTSB) investigators. To assist them in tracking the floating debris field in the darkness, the USCG called on the mapping capabilities of the National Ocean Service (NOS) and requested an assessment of other potential National Oceanic and Atmospheric Association (NOAA) assets in the region that could assist with locating debris.

After receiving word that an Alaska Airlines jet had gone down in the sanctuary, NOS plotted the site coordinates and mobilized its staff. Throughout the evening, they remained in contact with the USCG, assisting in estimating the drift of the floating debris field. At the Santa Barbara office, CINMS physical scientist Ben Waltenberger forwarded the periodic coordinates of the field, along with wind and sea conditions, to the USCG and the Hazardous Materials Assessment Division (HAZMAT).

At HAZMAT headquarters in Seattle, the data was put into a modified oil-spill modeling program and produced a projected path and dispersion rate for the debris. Although the model was developed for oil spills, Chief Scientific Support Coordinator Commander Jim Morris said it has many other applications. "You just have to change a few variables to make the model do something a little different."

Coordinates of the projection were sent back to Santa Barbara and loaded into the GIS. The same evening, the USCG cutter Point Carrew had a map with a projected path of the debris field for the next 12 hours. "In emergency situations, where you have to make quick decisions, the ability to visualize