Aguila, Arizona - The 174th Attack Wing at Hancock Field is mourning the loss of a former commander who died in a glider crash in Arizona.

Officials with the Maricopa County Sheriff's Office say retired Major General Robert Knauff died after a tow line failed on his glider causing it to stall. Police say the glider fell 100 feet.

Gliders must be towed into the air by another plane. Investigators still aren't sure how the mechanism disconnected. The NTSB has taken over the investigation.