ALBUQUERQUE —A medical plane crashed overnight in southwestern New Mexico, killing all five on board, including a young girl en route to a hospital with her mother, authorities said. A search helicopter found the wreckage early Monday.

Tracy Smith and 15-month-old Lily Smith were among those aboard the air ambulance. Lily was the patient, but it was not known what her ailment was.

The pilot was identified by Southwest Medevac as Ricky Byers, 56, of Dimmitt, Texas, who had worked for the air ambulance service for a year. The company said the other two killed in the crash were Brian Miller, a 44-year-old flight nurse from Roswell who had worked for the service for 1½ years, and Deanna Palmer, a 40-year-old paramedic from Prescott Valley, Ariz., who had been on the job one month.

Rugged, mountainous terrain marks the area where the plane went down; there were reports of nearby thunderstorms earlier in the evening but it wasn't known if weather was a factor in the crash. The cause was under investigation.

Smith, a single mother, worked two jobs _ at a golf course in the summer and as a ski instructor for the disabled in the winter, said William Riggles, who worked with her at Ski Apache. Everyone admired her commitment to her daughter, he said.

"She worked her tail off to make a life for that girl. She loved being a mom _ that was her world," said Riggles, also a ski instructor. "It's hard to make a living and raise a kid, and everyone really respected her for that. She put a lot of energy into giving Lily the attention she needed."

Smith had worked in Ruidoso since the late 1990s. Originally from Connecticut, she and her brother, who also lives in Ruidoso, grew up skiing and loved the sport.

"I just don't know how this ever happens to someone so nice," said Riggles, his voice cracking with emotion.

Bill Shipp, a co-worker at the Links at Sierra Blanca, said Smith wore many hats at the golf course, doing any duty that was needed.

"She was a grand gal and a super mother. She was just loving and caring to everyone," Shipp said.

The Beechcraft King Air E-90 turboprop plane was owned by Las Cruces-area Southwest Medevac which, according to the company, has been in business since 1994 and never had a plane go down. The company is a major provider of medical flights in southern New Mexico and Texas, and has 17 airplanes and helicopters registered with the Federal Aviation Administration.

"We've never had anything like this before and hope to never have again," said Rob Campion, a Southwest Medevac spokesman.

The company said flight operations, suspended after Sunday's crash, will resumed Tuesday morning. The company has arranged for counselors to be available to employees and their families.

According to FAA records, the company bought the turboprop in 2004 from a Mississippi company, which had owned it since 1991. Before that, the plane had more than a half dozen owners, including a Tennessee-based coal company that bought it in 1975 shortly after it was built.

The plane arrived at the Sierra Blanca Regional Airport near Ruidoso about 8:30 p.m. Sunday after a short flight from Roswell, according to FlightAware.com, a flight-tracking Web site. Earlier in the day, the plane had flown roundtrip between Roswell and Lubbock, Texas.

The plane left the airport later on a flight to University of New Mexico Hospital, and crashed almost immediately in Devil's Canyon in the Lincoln National Forest, said Peter Olson, a spokesman for the state Department of Public Safety.

The search began early Monday, and the plane was spotted about 5:15 a.m., Olson said,

New Mexico National Guard and state police helicopters helped locate the wreckage.

Gary C. Robb, an aviation lawyer in Kansas City, Mo., said the King Air "is a good aircraft with an excellent safety record. It's a very popular aircraft because it's reliable in use as an air ambulance service."

He said investigations of crashes involving air ambulances often focus on the "interaction of human factors and weather."

"It has been my experience over the years that these aircraft, whether it be fixed wing or rotorcraft, tend to fly in less than ideal weather because you've got to go," Robb said in a telephone interview.

Investigators for the National Traffic Safety Board also will look at the aircraft's maintenance history, engine systems and determine whether there were any emergency communications by the plane before the crash, Robb said.