The National Transportation Safety Board has issued reports detailing facts of two nonfatal helicopter crashes in Kona that occurred during instructional flights in May 2012 and in January.

On May 2 a two-seat Robinson R-22 helicopter registered to Mauna Loa helicopters suffered a hard landing after an apparent loss of engine power near Kailua-Kona.

Certified flight instructor Cody Johnson, then 27, told NTSB investigators that he had taken student pilot Pichanaut Wortapnitinan of Switzerland to practice “off airport approach and landings.”

During the flight, while Wortapnitinan was on the controls, Johnson noticed a “roughness” in the engine noise and felt the helicopter sink. Johnson took over the controls but heard the engine “going quiet, silent” as he attempted to right the craft.

At Johnson’s direction, Wortapnitinan attempted to restart the engine three times without success. Recognizing the steep angle of descent, Johnson said he flared and attempted to cushion the landing.

THE helicopter landed in a grassy field. Neither Johnson nor Wortapnitinan was seriously injured.
A post-accident examination of the helicopter by NTSB and Federal Aviation Administration inspectors revealed no abnormalities. However, the NTSB reported noted that “a carburetor icing probability chart revealed that the ambient temperature and dew point at the time of the accident favored serious carburetor icing at glide power.”

In the Jan. 30 incident, another Robinson R-22 helicopter, this one owned and operated by Hawaii Pacific Aviation, crashed during a training flight in Kailua-Kona.

Certified flight instructor Cristoph Klueh, 30, told an NTSB investigator that student pilot Sean Hardesty, 29, was practicing autorotations when the main rotor revolutions-per-minute began to “decay.”

Klueh took control of the helicopter and unsuccessfully attempted to correct the problem.

The helicopter landed hard, but neither Klueh nor Hardesty was seriously injured.

Klueh told the NTSB that there were no pre-impact mechanical malfunctions or failures that would have precluded normal operation.

The NTSB reports are on the findings of post-accident investigations but do not include determinations on probable cause.