Prop Clocking Matters

Kyle Boatright wrote:

I can tell you that 80 knots indicated is the minimum sink speed on
my RV-6 with the prop stopped, and the sink rate is 700-750 fpm at
that speed.

Huh. That seems fast, for an RV-6 (sink rate seems reasonable,
though). Van's lists the stall speed as 49 mph (43 kts). I would have
expected min. sink speed to be somewhere around 1.2 Vs, or 51 kts. 80
kts (92 mph) seems really high. My COZY has a stall speed of about 70
mph (61 kts), give or take, and the min. sink speed is around 80 mph
(70 kts), with a max L/D around 95 mph (83 kts). Sink rate at min.
sink is around 550 fpm.

Do you have sink rates for speeds from Vs up to 120 kts or so? I'd be
interested in seeing the #'s.

Thanks.

--
Marc J. Zeitlin
http://www.cozybuilders.org/
Copyright (c) 2007