The Civil Aviation Safety Authority (CASA) has extended the operating restrictions for those flying Jabiru-powered aircraft.
The regulator said those precautionary measures would be maintained until the cause of some power-related problems associated with the Jabiru engines were identified and rectified.
“Collaborative efforts involving Jabiru, Recreational Aviation Australia and the Sport Aircraft Association of Australia have been ongoing and productive, and it is hoped that an effective response to the problems will soon be identified,” CASA said.
Although the limitations that were imposed in December 2014 have been kept in place, CASA has eased one of the regulations regarding carrying passengers.
From July 1, CASA said a passenger may not travel in a Jabiru-powered aircraft unless they have signed a statement acknowledging the risk not more than three months before the flight.
Previously, the rule required a passenger sign a statement not more than 28 days before a flight.
“This change will reduce an administrative burden inherent in the current arrangements, without diminishing the precautionary safety benefits provided by the continuing operational limitations,” CASA said.
“For the time being, the other terms and conditions of the direction will remain the same.”
In December, CASA issued limitations on operators of Jabiru-powered aircraft, including restricting the flights to daylight hours and away from populated areas.
CASA also required trainee pilots to have successfully completed engine failure exercises before attempting solo flights.
The regulator said in November there had been about 40 identified incidents of Jabiru engine problems in 2014, ranging “from full and partial power loss and inflight engine shutdowns to rough running and oil leaks”.
Bundaberg-based Jabiru makes four-cylinder 2200cc and six-cylinder 3300cc aircraft engines. Figures from CASA indicated about 1,100 aircraft in Australia were fitted with Jabiru engines.