MADISON, Wis. -- Officials are beginning the process of piecing together what happened before a University of Wisconsin Hospital Med Flight helicopter crashed on Saturday night, killing all three crew members on board.

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The helicopter had traveled from Madison to La Crosse to drop off a patient at Gunderson Lutheran Hospital in La Crosse and was heading back to Madison when officials said they lost contact with the craft. Authorities launched a search on Saturday night and the crash site was found on Sunday morning.

A UW spokesman said that three people onboard the helicopter died in the crash. They were identified as Dr. Darren Bean, a physician, Mark Coyne, a registered nurse, and Steve Lipperer, the pilot. The three victims all lived in Madison, WISC-TV reported.

Officials said that the cause of the crash might not come for several months. Both the National Transportation Safety Board and Federal Aviation Administration are searching for clues as to why the helicopter went down, WISC-TV reported.

FAA spokeswoman Elizabeth Isham Cory said that the crash occurred at about 10:48 p.m. about three miles from La Crosse. UW Hospital officials said that the crash site was discovered at about 8:40 a.m., about four miles from the airport. Allan Tiedt, of the La Crosse County Emergency Dispatch Center, said that the crash site was in the Town of Onalaska.

The La Crosse Sheriff's Department, along with Onalaska and Shelby fire departments, found a portion of the helicopter's fuselage. The La Crosse Police Department said the location of the crash is near Kiel Coulee Road, which is on the bluff about five miles northeast of downtown La Crosse, according to WKBT-TV.

During a Sunday morning news conference, UW Hospital officials said that they no details on what happened, but preliminary reports suggest that the craft might have struck a hill and/or flown into some trees.

Authorities had set up a command post in the Town of Medary, which is about five miles northeast of La Crosse.

Residents Report Hearing Crash Saturday Night

Tommy Kammer, who lives near the crash site, said that he went looking for a car crash when he heard something on Saturday night.

"We heard what sounded like an automobile accident, where a car had run into a tree or crashed," he said.

Kammer said that the crash that he heard Saturday night was so loud it woke up his children.

"(I) actually went outside, put some shoes on and went looking around and listening for something and didn't hear anything," he said.

The helicopter crashed into a heavily wooded bluff just outside of La Crosse.

La Crosse County Sheriff Steve Helgeson said that local officials searched on Saturday and they too had trouble finding the site.

"The five fire departments stayed out all night with search teams searching the surrounding area," he said. "Because of the tall hills we have here, it's difficult sometimes to know exactly where sound is coming from, so we were checking a several-square-mile area looking for the potential downed flight."

Fire crews were out searching overnight. They said that they came up over a hill to find some damaged trees, then came down the hill to find the scene, WISC-TV reported.

Don Dominick, chief of the Onalaska Fire Department, said that search teams were committed to find the helicopter.

"I guess when there's people that work in the paralleling fields, it hits home a little harder," he said. "But I couldn't get the folks to stop last night. I tried to break them up, have them get some rest. They didn't want to stop."

A spokesman for Gunderson Lutheran Hospital in La Crosse said that their helicopter helped search for the missing one.

The victims' bodies were onboard and recovered.

Kammer said that he worries he could have done more.

"(I'm) actually devastated," he said. "I felt a little bad that maybe we should have been searching harder, longer, quicker. But, I wasn't quite sure what it was I heard."

Authorities Outline Timeline Of Crash

Officials said that the helicopter disappeared at about 10:30 p.m. after taking off from La Crosse. They said that they lost contact with the helicopter shortly after takeoff.

Between 10:40 p.m. and 10:45 p.m., hospital officials lost communication with the helicopter crew. At 11 p.m., the search effort began and La Crosse area residents reported a crash noise.

At 2 a.m., officials made a cell phone call to one of the victims' phones, which helped pinpoint cell towers the wreckage might be near. They also examined the flight plan and a point was intersected at the time the crash sounds were heard.

At about 8:45 a.m., the wreckage was discovered

Med Flight director Mark Hanson said that there were no concerns about the weather before the copter took off, but that rain and deteriorating conditions into the night caused the search to be conducted on the ground only.

Hospital Began Med Flight Program In 1985

UW Hospital spokesman Aaron Conklin said there's one other Med Flight helicopter that serves the university hospital system and it has been grounded.

Officials began the Med Flight program in April 1985. They said that the average trip for a patient pickup is about 55 miles, WISC-TV reported.

The UW's two helicopters were put into service last August and October.

Hospital official Don Cady said that ground transportation is the first line of defense if there's an emergency, but he also said other choppers around the state are available if the need arises.

Company: Helicopter Didn't Have Night Goggles, Warning System

A company spokesman said that the helicopter that crashed in Wisconsin didn't have two pieces of safety equipment recommended by the National Transportation Safety Board.

Mike Allen, senior vice president at Denver-based Air Methods, said that the helicopter wasn't equipped with a computerized voice system to warn of approaching terrain or night vision goggles for the pilot.

The NTSB recommended night vision goggles and the warning system in a 2006 report that suggested many fatal EMS flights could be prevented.

Hospital Holds Moment Of Silence

In honor of the victims, UW Hospitals held a moment of silence at 3:30 p.m.

Hospital officials said that they've received numerous offers of donations in the wake of the crash. They're directing people to page on their Web site and phone number, 608-265-6433, to handle such offers.

Stay tuned to WISC-TV and Channel 3000 for continuing coverage.

For More Info:

University of Wisconsin Hospital Med Flight Information