The Disney Parks Blog provided photos of the Seven Dwarfs Mine Train completing its first drop-test, where the ride car is pushed out of the station and allowed to run under gravity. This is done to test the mechanics of the push/pull system used to move cars into and out of the loading areas.
Take a look at the photos below:
The Seven Dwarfs Mine Train is due to open in 2014 in Magic Kingdom's new Fantasyland area, and will be the final part of the 'new Fantasyland' expansion project.