California’s firefighting agency has grounded 22 Grumman S-2T airtankers after a crash on 7 October killed a pilot in Yosemite National Park.

The precautionary grounded began on 8 October as the investigation of the crash began. Agency officials say they lost contact with the DynCorp International-operated S-2T, while local reports quoted witnesses saying the aircraft crashed into a steep canyon wall.

S-2T Tracker

Geoffrey “Craig” Hunt, 62, died during a water bombing mission on the Dog Rock Fire near Yosemite’s Arch Rock.

California has operated a fleet of S-2s since the mid-1970s, with each aircraft upgrade to turbine engines by 2005. The medium-sized tankers carry 1,400gal of water or retardant.

The 7 October crash is the latest in a string of fatal aerial firefighting incidents in the USA. Two incidents in 2012 killed six people and resulted in the loss of an Air National Guard Lockheed Martin C-130 and a Lockheed P2V-7 Neptune.