The single-engine Champion Citabria took off Saturday morning from Watsonville headed for the Sacramento area, but the wreckage was not discovered until early Sunday morning.
The coroner has not yet released their identities of the two people who were killed. It is still unknown exactly what happened.
The Federal Aviation Administration says the plane left Watsonville at 9:30 Saturday morning. When the plane failed to show up at a private airstrip near Sacramento Saturday evening friends and family members of the occupants reported it missing.
In the dark of the early morning, a Santa Clara sheriff's helicopter located the wreckage. An investigation into the crash is now in the hands of the FAA and the National Transportation Safety Board.
Sunday's recovery efforts to find the victim was led by Santa Clara County search and rescue workers.
"Friends and family members reported the plane missing to the FAA and we issued what's called an alert notice which basically lets all the relevant agencies know there is likely a missing plane in a certain area and that they should possibly start a search," said FAA spokesman Ian Gregor.
"The hardest part for downed aircraft in terrain like this is actually locating the aircraft. This terrain is very difficult to cover on foot. So, your only choices are to either to find the locator beacons that's in the aircraft and sort of follow that radio signal to the plane, or to locate the crash site visually," explained searcher Jeff Thomas.
The crash site is about half a mile from the roadside making Sunday's recovery effort especially difficult. The terrain is so steep the plan is to hoist the wreckage out via helicopter.
The plane is registered out of Sacramento, but it is unclear whether the owner was one of the two on board.
Conditions were clear Sunday but the FAA said it was not ruling anything out in terms of the investigation, including weather. They plan to review all the wreckage collected at the scene and talk to any witnesses if there were any. They will also inspect the maintenance records from the aircraft.