Glide Ratio Model IV

[Wheels]

IS there a published or approximate or wild guess as to the glide ratio of a model IV?
Its a parameter in the set up for Foreflight and while I don't expect to actually be that focused to my iPad, it might be nice to know.

Im thinking Best Glide as opposed to minimum sink. I guess I can stick it at 65 mph and read the handheld version of a Garmin GPS with that feature, but, if you know, ... do tell.

[Guy Buchanan]

From flight test, gross weight (1200#), temperature 60F, DA ~4500', engine idling (912s): glide ratio was about 8.6 at any speed over 60 mph. (Almost constant up to tested speed of 85 mph.) I did not test engine out. For reference minimum sink was 550 fpm at 45 mph. I did not test below 45 but looking at the curve I suspect it doesn't go much lower. (See attached.)

[Bud Davidson]

WOW! This is why I log in and read "New Posts" daily.

I have suspended work on my IV 1200 since hurricane Irma because of the cleanup and restoration workload. lost electric for 6 weeks, lost storage building where the Kitfox was stored but damage was to a wing and flaperon. electric restored temporarily and downed trees removed this week. Flood debris and crud left on items now pressure washed, and a replacement flaperon acquired due to the generosity of a kitfox builder. Replacing the storage barn will soak up any discretionary money so Kitfox priority slips downward. pre-formed windshield and prop were bought before storm so only paint and incidentals remain a cost, but any builder knows how those incidentals add up.

So, I will follow the forum and get back on the project in the coming weeks. The Forum keeps motivation high.

By the way, I have selected the two blade medium IVO ground adjust prop. Need a spinner. Any suggestions.

[Av8r3400]

Spinner: What look are you wanting? I really like the simplicity of my "skull cap" spinner.

IMG_1879.jpg

IMG_2952.jpg


It's the 5" version. My Prince will be a similar size at the hub to your IVO medium.

[Slyfox]

glide ratio of the 4. ha, I can tell you not much when the fan quits. now I had the experience of just that at 1000ft agl. I didn't fool too much with getting it started. I just located a nice field and went for it. sure it flew, yes it was quiet. I got down to the surface, maybe 5 off and noticed I was at 60mph. I went and pulled back for a nice landing and it dropped lock a rock. without the fan, any figures you may have for glide ratio, I say throw them out the window. these things drop below 60 was my experience. I held 90 all the way to the field I wanted to use. leveled and started to pull back at 60 and it dropped right out. so there you have it.

[jiott]

I know this thread is about the model 4, but FWIW the model 7 SLSA specifies about a 10:1 glide ratio with engine out and prop windmilling, and slightly better with prop stopped. This is from the SLSA POH, which I assume is a tested number since it is a certified aircraft.