The pilot of a light sport aircraft that crashed on Kauai in Polihale had problems with its fuel system, according to a preliminary report issued by the National Transportation Safety Board on Monday.

Pilot Gerry Charlebois, 54, and Mark McKenzie, 53, of Ontario, Canada, were killed on March 11  when a special light sport Revo Evolution Trikes weight-shift crashed and burned in Kekaha, Kauai. Charlebois was the owner of Birds in Paradise.

The NTSB said the trike departed from Port Allen Airport in Hanapepe about 8:50 a.m. and the introductory flight was intended to take 60 minutes before returning to the airport.

Charlebois recently had problems with the fuel system suctioning the fuel supply out of the main vent line, the preliminary report said.

The final NTSB report will be released in 12 to 18 months.

The incident was the first light-sport-aircraft crash on Kauai since 2011, when two separate crashes resulted in four fatalities. Two people were killed in a crash off Kauai’s south shore in February of that year. Then in May, a pilot and passenger died when a light sport aircraft crashed in waters off Kauai’s north shore.