Kaman has alerted K-MAX operators that the first fatal crash of the external lift helicopter, in Germany early in September, may have been caused by a fuel pump failure. The company is meeting engine manufacturer AlliedSignal to decide what action should be taken.
The single-seat, single-engined helicopter, operated by Helog of Switzerland, crashed 20km (12 miles) south of Kempten during a logging operation, killing the pilot. The K-MAX is powered by aT53-17A-1 turboshaft.
In a notice to operators, Kaman reports the preliminary finding of German accident inspectors, saying "...disassembly and inspection of the engine fuel control assembly has apparently revealed a failure of the primary and secondary fuel pump splines".
There have been two previous crashes involving the K-MAX, both non-fatal. One, at Kaman earlier this year, involved a US Federal Aviation Administration pilot who dug one wheel into the ground and flipped the helicopter over during familiarisation training. The cause of the other crash, also earlier this year and involving a K-MAX operated by Oregon-based Grizzly Mountain Aviation, has not been formally determined, but it is believed the pilot may have inadvertently shut down the engine.
Source: Flight International
