RAISINVILLE TOWNSHIP, Mich. - About one minute after Comair's Cincinnati to Detroit Flight 3272 leveled off at 4,000 feet, ''an event took place and all operations ceased,'' a federal air safety official said Saturday.
The twin-engine turboprop Embraer Brasilia 120 crashed about one minute later, killing all 26 passengers and three crew members on board, said John Hammerschmidt, chief spokesman for the National Transportation
Safety Board team investigating last Thursday's crash. The crash occurred in a field about 18 miles southwest of the Detroit Metro Airport.
Mr. Hammerschmidt said the ''event'' was detected in an early, verbal report on the cockpit recorder. He would not characterize what the ''event'' might have been or how the pilot and crew reacted to it.
His comments came during a press briefing Saturday evening at the Monroe County Community Mental Health Center after investigators spent another day picking through the
snow-covered wreckage in sub-zero temperatures.
''We haven't ruled anything in or out,'' Mr. Hammerschmidt said. ''It's an event we are trying to determine, to understand.''
He said 15 witnesses have been interviewed who saw or heard the crash. Seven of those were eyewitnesses, and three were witnesses who observed it for an extended time and had consistent stories.
''The key thing'' they said was that the aircraft rolled, leveled off briefly ''then the nose of the aircraft abruptly pitched down to the ground,'' Mr. Hammerschmidt said.
The cockpit's voice recorder kept running until impact, Mr. Hammerschmidt said. Prior to the ''event,'' the conversation between Capt. Dann Carlsen and First Officer Kenneth Reece seemed normal, according to an initial review by NTSB analysts in Washington, D.C. Mr. Hammerschmidt said the conversations recorded up until a minute before the crash indicated the flight was ''uneventful, routine, businesslike.''
Mr. Hammerschmidt said all eight of the propeller blades were turning on impact. ''All the deicing boots were found and appear normal except for impact damage.'' The deicing boots fit over the front edge of the wings and can be inflated in flight to break ice off the wings.
Icing can reduce the smooth flow of air over the wings, reducing lift on the aircraft.
NTSB investigators interviewed the crew that flew the airplane on another flight from Cincinnati to Detroit Thursday morning. That crew reported that they had used the deicing equipment and all systems on the plane had been working ''quite satisfactorily,'' Mr. Hammerschmidt said.
The scorched orange metal boxes containing the voice recordings and the mechanical flight data information were recovered Friday afternoon. They were flown to Washington, D.C., Friday night for further analysis.
The data recorder tracks numerous readings from the aircraft's instruments, including altitude, speed, fuel levels and flap settings.
NTSB investigators are looking at weather conditions on the day of the crash, including icing problems reported in the area, but Mr. Hammerschmidt said the weather was moderate with occasional turbulence and the pilot was aware of icing conditions in the area.
Saturday's revelations came as disaster crews spent their second full day combing the wreckage, gathering pieces of the airplane and remains of the 29 people.
Severe weather, including blowing snow and a 20-degree-below wind-chill factor, continued to slow their efforts. Crews could only work for 15 to 20 minutes at a time before having to return to a small shelter area for warmth.
Salvation Army and Red Cross volunteers from the surrounding area provided food and warm drinks. Counselors also were provided to help the crews, most of them from federal or local police agencies.
Mr. Hammerschmidt said none of the bodies was in one piece. The plane was seen by witnesses to roll out of the sky and slam into the ground, nose first.
From a cornfield across the River Raisin, just north of the crash site, observers could see crews sifting through the snow-blown debris with rakes. Evidence and remains being collected were put in large red, plastic tubs.
Crews used leaf blowers to expose the frozen ground. A crane was brought in next to large chunks of the airplane.
Remains were transported to a makeshift morgue at the nearby Monroe Custer Airport, where they are being stored in refrigerated trucks donated by the Meijer Inc. grocery chain.
No positive identifications of the dead have been released by the Monroe County Coroner.
Monroe County Sheriff's deputies were keeping the media and on-lookers far from the crash scene, the morgue and a grief center set up for family members of the victims in downtown Monroe, on orders of the NTSB.
NTSB investigators as well as those assisting in the investigation - officials from the Federal Aviation Administration, Comair, the Federal Bureau of Investigation and companies involved in building the aircraft - all were ordered not to discuss the crash.
Weather conditions were expected to be just as cold and harsh today , continuing to hinder the site investigation.
Meanwhile the investigation is continuing elsewhere. As part of a review of pilot and plane histories, investigators are expected to arrive Monday at Comair's headquarters in Erlanger to review the company's records.
The remote site of the crash plus the severe cold weather has resulted in little public display of grief by the people of Monroe County, even though it is the worst disaster in the area's history. Flags at local public buildings have been lowered to half staff, however, and a special memorial service is planned Sunday afternoon, organized by the chaplain of the Mercy Memorial Hospital in Monroe.
PROFILES OF VICTIMS
THREE DAYS OF CRASH COVERAGE
