Almost the entire fleet of United States Air Force (USAF) Lockheed C-130H Hercules transport aircraft have been grounded, according to media reports.   

The grounding followed the discovery of defective propeller assemblies, with 116 out of 128 USAF aircraft of this model affected, reports noted.   

The news was first reported by an unofficial Facebook Air Force amn/nco/snco channel.  

According to Defense News, the US Air Mobility Command confirmed the grounding in a statement, which also added that the first defective aircraft were discovered at Warner Robins Air Logistics Complex in Georgia, US.  

“When the propeller assembly was removed and turned into the WR-ALC Prop Shop, a technician noted a crack in the propeller barrel assembly. Upon subsequent inspections, two additional propeller assemblies were discovered with the same issue,” a separate Air Mobility Command statement, sent to Task & Purpose, said.  

All C-130H variants with old 54H60 propellers are affected by the issue.  

According to the reports, this includes 100 C-130H transporters, eight MC-130H Combat Talon special operations aircraft, seven EC-130H Compass Call electronic warfare aircraft, and one TC-130H trainer.  

Other C-130 models, such as the newer and more numerous C-130J, and C-130Hs with newer NP2000 propellers have been unaffected by the issue.   

The Lockheed C-130H, a variant of the earlier C-130C with more powerful engines, was introduced in 1974. Besides the USAF, small numbers of aircraft of this model are operated by other air forces such as Egypt, Algeria, Taiwan, Japan, Philippines, Singapore South Korea, United Arab Emirates and others.