The Airborne and Special operations Test Directorate was testing a new heavy-drop platform loaded with a Humvee, base spokesman Tom McCollum told Military.com.
"They were going in for a time-on-target on Sicily Drop Zone at 1 p.m.," McCollum said. "Everything was going well; they were at the one-minute mark to the drop zone.
"We don't know what happened, but the platform went out early and landed in a rural area. There was no one hurt. No private property was damaged."
The incident, which is under investigation, follows a similar airborne mishap that occurred in April 2016 when three separate Humvees came loose from their heavy-drop platforms and crashed onto a designated drop zone in Germany.
The Texas Air National Guard 136th Airlift Wing's C-130 Hercules aircraft completes a heavy cargo airdrop with a Humvee.
(U.S. Air Force photo by Julie Briden-Garcia)
For his role in the incident, Sgt. John Skipper was found guilty of three counts of destroying military property and one of lying during the investigation, according to Army Times.
A court-martial panel sentenced Skipper to be demoted to the rank of private and to receive a Bad Conduct Discharge.
In today's accident, the C-17 was flying at 1,500 feet during the heavy-drop test, McCollum said.
"Basically what takes place is a heavy drop pallet is inside the aircraft and by this time the doors have already been opened," he said, explaining that a pilot parachute pulls the platform out of the aircraft and three heavy-drop parachutes then open. "Everything worked as it was supposed to, except it went out early."
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