Well for those that are wondering if a pilot can contribute to an engine failure of this kind, the answer is yes. If a piston hits an exhaust valve this can usually only be caused by the valve ceasing as a result of perhaps lack of oil, overheating or some kind of lifter failure.
Jabs do have a tendency to overheat, particularly if flown at the documented maximum rate of climb, versus a faster climbout. If the aircraft was flown out fairly steeply for a prolonged period and temps were high a result like this could be expected, but not guaranteed. After a long taxi and slow climb this is conceivably possibly.
It is not uncommon for a J160 Jabiru to operate at redline CHT (with high oil temp) all day in 25 degree weather, particularly if heavily loaded due to pilot & pax weight and 130 litres of fuel on board. Most schools cruise around with 50-60 litres in the circuit for this reason. They are certainly not as robust as their larger GA counterparts and require specific operating knowledge.
Alternatively...
a. Valve Seat could have failed
b. Valve Spring could have failed
c. Fly-wheel bolts could have broken (and stuffed up the timing)
All of these could cause the valve to hit the piston.
There is a current Jab AD on the flywheel bolts, however I'd assume it was done, but then again if not done properly could have fallen off.
We shall wait and see the result...
Last edited by Squawk7700; 28th Jan 2007 at 06:21.