USA–– RALEIGH, N.C. Four crewmembers aboard a North Carolina Air National Guard plane fighting Western wildfires were killed last summer because the crew misjudged conditions and flew into a wind burst that slammed them to the ground, an Air Force crash report says.
The C-130 Hercules air tanker crashed July 1 in South Dakota’s Black Hills. The accident investigation report released Wednesday by the Air Force Air Mobility Command says it happened because the crew flew into a microburst five minutes after the pilot managed to save the plane from an earlier violent downdraft.
A microburst is a narrow wind gust that rushes downward out of a thunderstorm. A plane flying through it at low altitude can quickly lose the lift that keeps it aloft. A microburst is typically less than 2.5 miles in diameter and lasts for less than five minutes, the report says. Four of the six crew members from a North Carolina Air National Guard unit died in the crash. Two crewmen were injured.
“If you add all of the pieces up, they really should not have attempted the second drop,” said U.S. Air Force Brig. Gen. Randall Guthrie, who headed the crash investigation. “There was enough indications of stuff that was going on as far as the performance of the airplane, in the operations they were in, that they should have avoided the drop.”
The report says two other plane crews on the scene failed to communicate critical information and the C-130’s crew also received conflicting information on how far to stay from an approaching thunderstorm.
One of the two small, twin-engine planes arriving near the spot the C-130 was to drop flame retardant described flying through violent air churned by a thunderstorm 10 miles away, Guthrie said.
Despite that, the tanker made an initial pass into the target zone and was battered by wind so dangerous the pilot lost airspeed and struggled to stay airborne, Gutherie said. The C-130 dropped some of its retardant, then circled back around for a second attempt.
A lead plane guiding the tanker into the drop zone said on the radio it was losing altitude and had to get out of the area, but that pilot didn’t describe it as another potentially deadly microburst, Guthrie said. The thunderstorm was now 5 miles away, he said.
The C-130 started to feel the danger, too.
“They pushed the engines up to maximum power and pulled the nose up in an attempt to climb away from the ground,” Guthrie said.
The big plane’s pilot fought the wind for 13 seconds before the lead plane recommended the tanker dump its retardant to lighten its weight. It was too late. The tanker crashed about four seconds later into a lightly forested plateau, then slid downhill about 400 feet into a tree-lined ravine that broke apart the plane’s body. The victims died on impact, Guthrie said.
The two surviving load specialists in the back of the plane evidently crawled out through a hole shredded by one of the propellers dislodged by the impact, though they didn’t remember their escape, Guthrie said.
Besides the crew of accompanying planes failing to tell the C-130 pilot details of the violent weather that might have persuaded him to scrub the second pass, Guthrie said the tanker’s crew got conflicting directions on the minimum safe distance from thunderstorms. An Air Force command said to keep at least 5 miles away while a National Guard guideline was at least 25 miles, Guthrie said.
The North Carolina Air National Guard said in a statement it would study the accident investigation’s findings to prevent future tragedies.
The four who died were Lt. Col. Paul K. Mikeal, 42, of Mooresville; Maj. Joseph M. McCormick, 36, of Belmont; Maj. Ryan S. David, 35, of Boone, and Senior Master Sgt. Robert S. Cannon, 50, of Charlotte. Mikeal and McCormick were both pilots, David was a navigator, Cannon was a flight engineer.
They were members of the Air National Guard’s 145th Air Wing, which was pressed into service to fight wildfires that burned thousands of acres and destroyed hundreds of homes in Colorado, Wyoming and South Dakota. Their aircraft was flying out of Peterson Air Force Base, Colo., at the time of the crash.
The plane was assigned to a wildfire that scorched 14 square miles near Edgemont, S.D., before it was contained with the help of rain. The burned lands were primarily National Forest grasslands and timber, although some ranchers were affected.
The Charlotte-based unit sent three C-130s and 36 men on the firefighting assignment but cut the mission short after the crash.