here one moment, gone the next! Fire engine falls into a sinkhole at 9.82 m/s2

Skip the first half of the video (of course) and poof, like a magician made it disappear.

A five-lane, 3-mile stretch of southbound Interstate-15 is down to two lanes in California’s Cajon Pass after a portion of roadway washed away, causing a fire engine to tumble off the side of the highway between Highway 138 and Cleghorn Road, according to San Bernardino County Fire spokesman Eric Sherwin. All firefighters on board were able to escape before the engine fell a few minutes later.

SO, they had already realized it was dangerously parked, but didn't move it. Gravity did though

The engine was initially dangling over an edge when water erosion from ongoing storms caused the roadway to suddenly fail Friday night. All firefighters on board were able to escape before the engine fell a few minutes later.

http://www.reviewjournal.com/traffic/storm-closes-part-southbound-i-15-california-s-cajon-pass-fire-engine-falls-highway

http://www.reviewjournal.com/news/nation-and-world/southern-california-recovering-rain-north-confronts-renewed-storm
thanks Steve!