Prop Tape Performance (or not)
I saw mentioned in another thread that someone had removed the prop leading edge tape from their Catto prop and gained 3 mph. And someone else said they felt they gained more than that. OK, well I'm up for trying that.
Notes- I had installed the tape, not the factory. Tape was .008" thick, 2 inch wide, edges cut with pinking scissors to give a zig zag trailing edge as I'd read a study that that is better than a straight step. Install wasn't perfect - had a 1/8" bubble on the leading edge near the tip on both blades. Hard to get the tape to conform to the swept back Catto leading edge.
Did a simple test of True Airspeed as reported by the Dynon, all tests at around 8000' density altitude.
With tape, 2 weeks ago:
7970’ DA per D10A, WOT, not leaned out. Top speed 179 TAS 2760 rpm. Approx 30 Gal onboard. Thus 175 mph / 152 kt @redline, calculated.
Without tape - today:
8020 DA per D10A, WOT, not leaned out. TAS 179 mph – but at 2670 rpm. 90 rpm lower, same speed! No leaning last time as was already at 2760.
So – leaned out to ROP.
8040 DA --- 183 mph, 2710 rpm. Gained 4 mph. vs. with tape - at less RPM.
Recheck at 7510 DA --- 2710 rpm, 72% HP per JPI, 183 mph TAS. Approx 25 Gal onboard.
Thus 182 mph / 158 knots @redline calculated.
I'm astonished by the change. The only other change than removing tape is about 5 gallons less fuel on board.
I had this prop repitched (more pitch) and was fairly disappointed in the change. But I had installed tape before doing any testing. With the tape off it is entirely different.
RV6A in phase 2 as of April 2016
Donation made Oct 2020