Investigation & Crash Animation of fatal Marine Corps C-130 crash that killed 16. Sloppy maintenance work at an Air Force depot was at the root of a tragic crash of a Marine Corps Reserve KC-130T that resulted in the deaths of 16 service members in July 2017.
On July 10 of last year, a KC-130T military transport plane based out of Stewart Air National Guard Base in Newburgh crashed in a soybean field in Mississippi, killing 15 Marines and a Navy corpsman.
Seventeen months later, investigators say the most deadly Marine crash since 2005 was caused by a propeller blade that broke off at 20,000 feet.
According to a command investigation and about 2,000 pages of supporting documentation, obtained exclusively by Defense News and Military Times, a corroded blade broke off of the aircraft, sliced through the fuselage, and set off a chain of events that ended with the plane splitting into three pieces and crashing into a Mississippi soybean field.
The blade was last overhauled at Warner Robins Air Logistics Complex in 2011, where civilian maintainers are responsible for rooting out corrosion and other such problems. But although the investigators found evidence that small cracks and pits were already present in the propeller blade, maintainers did not properly treat it — allowing it to grow into a long fracture.
Crash Animation of C-130 crash
Among the victims were nine Marines based at Stewart, including Fishkill Gunnery Sgt. Brendan Johnson. Other victims included an elite Marine Raider battalion based at Camp Lejeune, North Carolina.
The report on the causes of the crash, released Wednesday, slams “consistent production errors” at Warner Robins Air Logistics Complex in Warner Robins, Georgia, saying evidence from the crashed plane shows employees missed growing corrosion on the key propeller blade during a 2011 overhaul. The report finds workers at the base did a poor job of following the Navy’s specific procedure for its propellers, in part because the vast majority of blades overhauled at the base followed different procedures. The report indicates the Air Force has now agreed to adopt the Navy’s more demanding overhaul procedures for all propellers.
Military officials have known of the problems since at least September 2017 and some family members had previously indicated they knew what had happened, although they declined to discuss details.
Now, the Air Force is taking steps to make sure that those mistakes are never repeated.
“We have commissioned an independent review team made up of experts from the Navy, Marine Corps the Air Force and industry to look at the blade overhaul process, to revamp that process, to ensure that we have the proper procedures, the latest technology, the right technical manuals and the right training,” Brig. Gen. John Kubinec, the current commander of WR-ALC, said in a recent interview.
The team has come up with a standardized overhaul process that can be applied to Air Force, Marine Corps and Navy propellers — a massive departure from the procedures used in 2011, which set special standards for Navy and Marine Corps blades.
WR-ALC halted all C-130 blade overhauls in September 2017, when investigations first revealed the root of the July mishap. It started working with the other parties in the independent review team on a single, streamlined overhaul process for all the services’ blades, and the new process is currently under review, Kubenic said.
Most likely, it will be validated in time to restart blade overhauls in January 2019, stated Wendy Varhegyi, a spokeswoman for Air Force Materiel Command.
The new 21-step process is “largely similar” for both the Air Force and Navy blades, with “a very small number of differences due to service-unique propeller configurations and differing engineering assessments,” Varhegyi said.
Preventative recommendations made
The report lays out 17 recommendations to prevent a recurrence. Brig. Gen. John Kubinec, commander of the Warner Robins Air Logistics Complex, told The Telegraph of Macon that the base expects to restart propeller overhauls early next year.
“When we first heard that work done here in 2011 may have contributed to the mishap, leadership and the (propeller) shop were devastated,” Kubinec said. “The first thing we did was take action to ensure that processes were in place that this wouldn’t happen again. That’s what our commitment has been since we first heard about it.”
The report says a corrosion pit eventually developed into a crack, breaking off from the propeller closest to the fuselage on the left-hand side of the plane. A number of other propeller blades on the four-engine aircraft were also found to have corrosion. The report said investigators found a protective coating had been painted over corrosion on some blades from the plane, proving that Warner Robins Air Logistics Complex workers “failed to detect, remove and repair corrosion infected blades they purported to have overhauled.”
The report said inspectors visiting the base were dismayed to find workers relying on memory for how they should conduct propeller maintenance, even though they had laptops with the correct procedures at their work stations. They also said technicians did a poor job of tracking paperwork that said who a propeller belonged to, which determined whether they were supposed to use methods for the Air Force, the Navy or P-3 surveillance planes. Plus, quality inspections did not cover “the steps regarding identification and removal of corrosion.”
The Air Force doesn’t know which technicians inspected the blade in 2011, though, because its previous policy was to dispose of maintenance paperwork after two years. Although the Navy had the power to audit work done by the Air Force in Georgia, the report says there’s no evidence any audit ever occurred since the Navy handed off the work to the Air Force in 2009.
Read Details analysis on the report here: www.defensenews.com
Insufficient inspections in Newburgh
According to the report, the Marine Aerial Refueler Transport Squadron 452 was supposed to perform an electrical current inspection on blades any time a plane didn’t fly for more than eight weeks, but did not.
However, investigators said that even if maintenance workers had conducted inspections they missed, they might not have found the problem.
“It cannot be concluded with any reasonable degree of certainty that the radial crack would or would not have been detected,” investigators wrote.
The blade sliced through the fuselage where passengers were sitting, lodging into the interior of the right hand side of the skin. The impact affected the drive shaft of a propeller on the right side, causing that propeller to break loose, causing it to hit the fuselage and then knock part of the stabilizer off the plane. The plane, then basically uncontrollable, broke into pieces, and the area containing passengers “explosively disintegrated.”
The report says all aboard suffered “shock, disorientation, inadvertent physical responses, rapid onset of below freezing conditions and near impossible crew communication.” All the men died from blunt force trauma and contusions, investigators found.
Despite speculation at the time, the report found “no evidence of inflight fire damage or ammunition discharge.”
The Navy grounded its fleet of C-130Ts until propellers are replaced, with Congress appropriating $121 million to accelerate the work. However, the aging KC-130T models like the one that crashed are being phased out. C-130s have historically been one of the military’s safest aircraft.