IVO InFlight Adjustable

[kmach]

If money was not a factor , I would select the Airmaster as first choice.

My personal story,
I had the 2 blade Sensenich ez pitch , a very nice prop.
I always read of a three blade prop being smoother and was intrigued by the three blade IVO GA and how it adjusted. A medium 3 blade ground adjustable came up for sale on barnstormers for a decent price so I bought it.

I liked how the GA IVO medium performed, but I knew there was the ability to make it an IFA, so it eventually was made into an IFA.
So far the best setup that I have had.
I would like to try the Airmaster with Whirlwind blades , but I can't justify the dollars to switch at this point.
Maybe one day ?

P.S. I put John McBean's advice very high and take it for being about the best there is.

[herman pahls]

I appreciate your responses regarding the IVO IFA props.
I will try to summarize what I have learned from several members on this forum by posts, PM's and phone calls.
I was searching for a new prop because I was getting the impression that I was prematurely damaging my 912ULS engine, gear box, starter and sprag clutch by using the 70" Warp Drive, taper tip with nickel leading edge.
So I called Warp and they told me my WD prop's MMoI was just over 5000 which is short of the Rotax suggested 6000.
I tried calling IVO to find out what the IVO Medium IFA props MMoI is but they are not open till the 1st of the year.
Warp claims my prop weighs 10#'s, IVO online says the medium weighs 17.2 #'s, the Airmaster weighs 26 #'s (and uses Warp or Whirl Wind blades) and the Whirl Wind 3 blade ground adjust weighs around 9 #'s from what I could find.
I talked to 2 Kitfox owners that use the Airmaster.
One was getting 130 + mph on 26" ABW's burning 4+ GPH with the smooth model 7 cowl. Your life would be on the line if you tried to take that prop away from him.
The other was getting much less cruise and higher fuel burn, also on 26" ABW's but with a round cowl model 5. This owner is considering a long Prince prop because he felt that from riding with Steve Henry in his Highlander that the take off and climb was significantly better than his Airmaster at 5800 RPM and the Prince was only turning 5300 RPM. Also, he felt the Prince prop fit his flying interests better even with a loss of cruise speed.
Since the Airmaster would add 16 pounds to the nose of my model 4 and hiding $8000. from my wife is not an option at this time, I will not be flying with a real constant speed prop in the near future.

My Conclusions regarding some of the props used for Kitfox's with 100 hp engines.

The Prince is right up there with being the best if not the best short field prop.
I do not know of any flying on a Kitfox to hear what cruise speed they get.
Larry will be telling us soon.
My concern is having to send the Prop back and forth to the factory to get the pitch right if needed.
This long prop really needs tall tires and extended gear to get the blades out of harms way.
This is probably the lightest prop and only takes 5 minutes to install and torque. That appeals to me.

If affordable, I would have an Airmaster. I love not chasing the RPM.
I feel they are a better fit for the Super Sports than the model 4's or possibly the 5's due to dealing with the extra weight and C.G..
All around performance and fuel burn would be hard to beat.

We possibly need to convert round cowls to smooth cowls for efficiency.

Warp Drives are probably the least damage prone prop, and in my Kitfox give good climb and cruise and could be used to chop wood when you replace it.

Warps and IVO ground adjust are probably the best bang for the buck from what I could find. Possibly the best seaplane prop option.

The Whirl Wind is probably the lightest, most efficient and vulnerable to damage and reasonably priced.

Since I want maximum RPM for gravel bar hopping and decent cruise when trying to get somewhere, the ease of making pitch changes would make the IVO my first choice from what I know now.If I go with Big Bore cylinders my current WD will need to be replaced.

If you know what the weight and MMoI is on the props you have used, please share that info..
If my information is not correct or you know of better options please let me know.
If you have an IVO medium prop for sale, I am interested.
Herman

[Geowitz]

IVO won't give you a MMOI. At least they wouldn't when I purchased from them. However, I did my own test and the results of a medium 72 inch 3 blade and 2 blade are posted in this thread...

http://www.teamkitfox.com/Forums/sho...geowitz&page=2

3 blade medium 72 inch with in flight adjust = ~ 7800 kg cm2
2 blade medium 72 inch with in flight adjust = ~ 5300kg cm2

The original link to the test procedure is bad, but this video is how I did it.

http://www.eaavideo.org/video.aspx?v=2010764613001

[herman pahls]

Geowitz
Valuable video showing how to test for MMoI.
I wonder how many are going to stop using the 3 blade IVO medium because it exceeds the Rotax recommended MMoI.
Now I am now curious how my Warp Drive will test even though WD told me it would be just over 5000.
Any suggestions of what wire to use? Diameter?
It seems like the initial angle the blades were rotated was vague.
Maybe it is not that important.

Any other confessions what the MMoI of the other brands of props is?
I am curious how the Airmaster would test with Whirl Wind and Warp blades.
Herman

[Geowitz]

Here's the service information from Rotax with written instructions.

http://www.ultralightnews.ca/cdrive/massweight.pdf

The wire is just described as "thin". I used .035 MIG wire since it was handy around the shop. The initial degrees of rotation is not exactly critical, but they say 5 to 10 degrees.

I don't think many (if any) would stop using the IVO... So far it doesn't seem to really be an issue at least with the medium on the 100hp.