YOSEMITE NATIONAL PARK . (AP) — California’s fleet of 22 air tankers was grounded Wednesday after one of the planes crashed while battling a wildfire in Yosemite National Park, killing the pilot.

A National Park Service helicopter and air tankers from the U.S. Forest Service were filling the gap and assisting firefighters tackling the blaze that prompted the evacuation of 60 homes in the community of Foresta, park spokeswoman Kari Cobb said.

It was not clear how long CalFire’s grounding of the S-2T airplanes will last as the agency checks the safety of the aircraft and its pilots, CalFire spokeswoman Alyssa Smith said.

The tankers are part of a CalFire fleet that includes 11 UH-1H Super Huey helicopters and 14 OV-10A planes used to guide the other firefighting aircraft.

The tankers, however, are the backbone of the firefighting fleet and can each carry 1,200 gallons of fire retardant.

“These are our initial attack aircraft,” department spokeswoman Lynne Tolmachoff said.

The crash occurred on Tuesday as four California Department of Forestry and Fire Protection aircraft, including three tankers, were fighting the blaze as it climbed a steep canyon wall north of the Merced River, Tolmachoff said.

One of the planes hit the canyon wall and disintegrated, spilling pieces of the twin-engine aircraft onto State Highway 140.

The body of pilot Geoffrey “Craig” Hunt was recovered Wednesday. It was draped with a flag and accompanied by an honor guard as it was turned over to CalFire officials.

Hunt, 62, of San Jose was a 13-year veteran pilot of DynCorp International and flew the air tanker under a contract with the state.

“We know wildland firefighting is an inherently dangerous job, but Craig made the ultimate sacrifice,” CalFire Director Ken Pimlott said in a statement.

Mike Lopez, president of the union representing CalFire firefighters, said Hunt had extraordinary skill and talent.

Gov. Jerry Brown added his condolences in a statement, while ordering the Capitol flag to be flown at half-staff.

The fire had grown to 252 acres by Wednesday afternoon, though some of the smoke had lifted, said park fire information spokeswoman Jennifer Wuchner. Electricity was out in Yosemite Valley because power lines near the crash site were shut down, and park facilities were using generators, she said.

Highway 140 will be closed indefinitely because of rocks rolling onto the roadway and as the crash is investigated by the Federal Aviation Administration and National Transportation Safety Board. Officials said the weather at the time of the crash was clear and winds were calm.

Tolmachoff said it was unclear if smoke from the fire or isolated updrafts or downdrafts within the canyon might have played a part in the crash.

Department spokesman Daniel Berlant said he was not aware of any radio distress calls from the pilot or any radio traffic from other pilots indicating problems with the weather or with the downed aircraft.

DynCorp International provides pilots for all CalFire planes and maintenance for the department’s aircraft.

The downed tanker — like others in the fleet — had been built as early as the 1950s as an anti-submarine warplane, said Berlant. It was retrofitted to an air tanker in the 1970s and rebuilt again in 2001 so completely that the Federal Aviation Administration website lists it as manufactured in 2001.

“It was rebuilt enough that it qualifies as a new manufacture date,” Berlant said.

Berlant said the age of the fleet has not been a problem in the past. However, that has not been the case for federal firefighting aircraft from the same era, some of which have lost their wings in midflight.

The precautionary stand-down of the tanker fleet came in the midst of a fire season that has been extended by drought and unseasonably hot, dry weather.

Department helicopters were available to help fight wildfires, said Smith, as was a DC-10 on standby and capable of dropping large amounts of fire retardant. The agency can also call on aircraft under contract to federal agencies, or request the use of specially equipped California National Guard helicopters and air tankers.

The last time the S-2Ts were grounded was in 2001, when two of the aircraft collided while fighting a fire in Mendocino County, killing both pilots, she said.

Pilots of a different type of aircraft were grounded for the same reason in 2006, when a fire battalion chief and a pilot were killed while observing a fire in a two-seat plane in Tulare County, she said.