The National Transportation Safety Board has released its preliminary report for last month's fatal plane crash near Johnstone Bay.

According to the report, a Helio Courier aircraft crashed on June 21 around 3:46 p.m. in tree-covered terrain about 25 miles southeast of Seward, killing the three people on board: pilot Kem Sittib of Fairbanks and passengers Michael and Traci Timmer of Hopkins, Michigan.

The Timmers had been dropped off in a remote area near Johnstone Bay by an air taxi on June 18. They were scheduled to return to Seward on June 25, but requested an earlier pickup.

The air taxi owner said when the Timmers called for an earlier return flight, his company airplane was configured with skis and therefore not suitable for landing on the makeshift airstrip where they would need to be picked up. 

The report states that another pilot offered to pick up the couple for free using his personal ski-equipped Helio Courier. That pilot left Seward Airport at 2:50 p.m. on June 21. The air taxi owner said he tracked the plane's movements but, when it didn't return, he began an aerial search in his personal Piper Super Cub.

After some time in the air, the air taxi owner reported seeing burning wreckage near the departure end of the landing site. 

The next day, the lead NTSB investigator, Alaska State Troopers and Federal Aviation Administration air safety investigators flew to the accident site in a trooper helicopter to investigate.

They found the crash site south of the airstrip resting on the shoreline of a small river from Little Johnstone Lake that flows into Johnstone Bay. Investigators discovered what they believed to be the impact point of the plane marked by a broken treetop, located in an area with 100-foot tall trees at the end of the airstrip.

According to the report, the plane caught fire after the crash and most of the wreckage was incinerated in the blaze. There was no flight plan filed, and weather conditions in the area were reported as clear with visibility of 10 miles.

Some wreckage was recovered and is now being examined and processed by responding agencies. The cause of the crash remains unknown.

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