rcarsey
Well Known Member
I did a quick search and didn't see this topic come up yet. Rotax issued SI-912i-027 on 2021-May-28 (also attached here)
It is about ensuring the mass-moment of the propeller is within a certain range for the 912/912i engines. They have you suspend the propeller/hub assembly by two parallel wires. Give the assembly a 10 degree turn, and measure the time it takes for 30 back-forth motions. Then look some numbers up on a chart.
I will assume that the measurements for all of our -12/-12iS aircraft (with factory propellers) would be about the same.. so no need for every owner to test their setup.
But just wanted to start this topic in case anyone has additional information.. or in the off-chance that someone changed to a non-factory propeller/hub.
It is about ensuring the mass-moment of the propeller is within a certain range for the 912/912i engines. They have you suspend the propeller/hub assembly by two parallel wires. Give the assembly a 10 degree turn, and measure the time it takes for 30 back-forth motions. Then look some numbers up on a chart.
I will assume that the measurements for all of our -12/-12iS aircraft (with factory propellers) would be about the same.. so no need for every owner to test their setup.
But just wanted to start this topic in case anyone has additional information.. or in the off-chance that someone changed to a non-factory propeller/hub.