Prop obsevations

[Corby202]

I thought I would share the differences between two props. I now have 36hrs on my plane, Jab 2200 ( 3300 rpm redline). Up until a couple of weeks ago I had been using a Sensenich
60X46 prop that I purchased from Jabiru. The prop was on special and advertised as a climb prop. The flight test paperwork that came with the prop showed that when being tested on a Jabiru J120, At 3350 rpm the aircraft was doing 112 knots.
I found the prop to be very good in climb usually seeing 1000-1100 FPM climb solo at 80 knots (700 with a passenger), 3100 rpm.S&L, 2900 = 105 knots, 3300 = 120 Knots, WOT I saw 125 at3350 but backed off although the engine would have revd more. Whilst flying I had to be careful of those revs as a powered descent would push the revs to high. Straight away you can see how slippery the Sonex is compared to the Jab which is not bad aircraft anyway.
A friend was selling a 20hrs old 56X48 Brent Thompson prop, a New Zealand manufacturer, the company has since changed hands a couple of times so I can not comment about the quality now.(This prop was too much for the Corby Starlet he had it on)
The numbers for the new prop (only a few tests so far), climb solo most certainly down, 700 fpm at 80 knots 2850 rpm. S&L 2900= 122 knots WOT 3150 =138 knots. With a 80kg passenger the climb is a pathetic 550 fpm but in cruise the numbers were only a few knots down to solo performance.
The other strange thing with the smaller diameter prop is the amount of extra yaw it creates on climb, I would have bet money the opposite would have been true.
These tests were done at YMIG, field elevation 2000' plus its cold here at the moment 10 deg C.