We're learning more about what happened in the moments leading up to a deadly Sioux Falls plane crash.
The National Transportation Safety Board released its preliminary report
on Monday; it includes witness reports and new information on the incident and aircraft itself.
It turns out the Cessna crashed just days after passing its yearly inspection.
The left engine was replaced in April of 2004. The right engine was just installed in October of this year.
And according to the report, the older of the two engines appears to be where the problems started.
Witnesses noticed white smoke coming from behind the left engine as soon as the plane took off. They then noticed fire in between the left engine and the fuselage.
At that point, witness say the plane began to turn left.
According to the NTSB's preliminary report, the Cessna was on its way to Rapid City when 30 seconds into its flight, the air traffic controller informed the pilot of visible smoke coming from the plane.
"It appears he was trying to return to the airport to salvage the airplane or do the best he could with it," Harry Hybertson said.
Hybertson is a flight instructor and has read the report. He says it appears the pilot lost his left engine and that's critical.
"Just to put it real simple, when you lose one of two engines, you've lost 50 percent of your power. When you've lost one of two engines, you've lost 90 some percent of your performance. It's a big difference," Hybertson said.
Hybertson says the pilot was probably going through his emergency procedures, but he added that type of airplane is tough to fly when something goes wrong.
"It's possible if everything is just right you can fly it on one engine, but if something else goes wrong and then you're in big trouble," Hybertson said.
According to the report, the left engine had nearly 1,500 flying hours on it.
"That was probably close to TBO, which is time before overhaul and that's recommended," Hybertson said.
But Hybertson says that wouldn't have caused the engine to stall.
Four people lost their lives in the plane crash. They are pilot Brian Blake and passengers Daniel Swets, Kevin Anderson and Josh Lambrecht.