LEBANON — The Piper airplane crash last week near the Warren County Airport was caused by a door popping open, according to the preliminary report of the National Transportation Safety Board.

The plane crashed near Mulford and Greentree roads on Wednesday. The family of the pilot and the passengers told the Middletown Journal after the accident there were issues with the plane, pointing to a problem with the safety latch.

The pilot, Zeb Bowles, his two brothers, Wilson and Zachary Bowles, and Zachary’s wife, Kathrine Bowels, were injured. The brothers received minor injuries, according to the report, and were treated and released from Atrium Medical Center.

Kathrine Bowles, 30, was listed in critical condition on Tuesday afternoon in the intensive care unit at Miami Valley Hospital. The brothers are originally from California and Zeb and Wilson Bowles now live in Colorado; Zachary and Kathrine Bowles live in Lebanon.

The report indicates Zeb Bowles was piloting the plane when it returned to the airport after the door “popped open.”

“The pilot returned to the airport but decided to fly a go-around. The pilot reported that there was a loss of engine power when the airplane was on the base leg of the traffic pattern. The pilot attempted to land in a nearby field but the airplane struck trees and power lines,” according to the report.

Keith Holloway, an NTSB spokesman, said the agency does not issue any penalties or fines based off its investigation, but rather would make recommendations to the FAA. The NTSB will follow up with two additional reports, a factual report that could take up to six months and a final report that could take 12 to 18 months to complete.

Wilson Bowles told the Middletown Journal last week his brother, Zeb, had gotten his pilot’s license three months ago, but has been flying since he was 15.

The preliminary report indicated Zeb Bowles was flying using visual rules and did not file a flight plan. FAA spokeswoman Elizabeth Isham Cory said there are no requirements to file a flight plan “if they are flying by visual rules.”

Contact this reporter at (513) 820-2175 or Michael .Pitman@coxinc.com.