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Hello brains trust.

Are any of you using the E-Prob carbon fibre ground adjustable props?

I'm not sure how the performance would compare to the 2 blade fixed pitch WC props that are now being sold through Sonex but I would switch and enjoy the lighter weight and hopefully either gain a bit of performance or at least not lose any

Any performance figures would be appreciated especially if using with a Rotax.

I am thinking of switching to one of these instead of trimming my Sensenich WC64QR-82G wood composite fixed pitch (due to being way over propped).

I just replaced my three blade FITI propeller on my Bristell with the 1750mm three bladed E prop. Overall TopSpeed performance is similar, as you would expect, however, at 4.4 pounds total weight, including the hub, this thing is a featherweight, and almost all noise associated with propeller pulse is all but gone. It is by far better in every measurable metric and spot on with top speed. I suspect there’s another couple of knots if I push the prop all the way to 5500 at max RPM but currently, in level flight at full throttle I’m at 5650 RPM.

Highly recommend, particularly when you consider how little wear this propeller will put on a Rotax gear box

Thanks Chris,

I ordered the 3 blade 160cm (63") ground adjustable and hope to start testing it soon. I have enough performance Data to be able to compare it to the 2 blade Sensenich I had on the Waiex. I will also weigh the 2 and compare weights as this one seems light as a feather.

How is the Eprop project going Murray? - any erly data?

Skippydiesel wrote:How is the Eprop project going Murray? - any erly data?

I have only flown it once. I set the static to 5500 rpm and thought it would need more pitch but gave it a trial flight first. To my surprise, once I started rolling down the runway the engine loaded up more and bogged down to 5200 rpm. I was about to abort takeoff but I quickly became airborne, and the RPM dropped further to 5000 and climb performance was anemic. Full throttle WOT only saw 5200 rpm at 140 KTS.

E-Prop recommends 33 degrees pitch for the Sonex/Rotax combination, I did the first static test at 31 degrees and the engine went to max RPM (5800) so I went to the recommended 33 degrees and got 5500 RPM on that static run. I thought it would need more pitch than that so I went to 34 degrees and that static run still only went to 5500 RPM so I did the flight test at that setting.

I have removed 2 degrees of pitch (now 32 degrees) and will try again soon.