IVO medium inflight adjustable prop

[1avidflyer 1983]

Any one running an IVO medium?  2 or 3 blade?  How about with the constant speed governor?  Any one know how that governor works?   Inquiring minds want to know..... (or at least one does :-)   Any comments welcome.  JImChuk

[Allen Sutphin 705]

I've never dealt with the IVO CS, but the WD uses an electric system for pitch adjustment. But it was either cruise or take-off position. No infinite adjustment.  Most all IFA (constant speed) props are oil controlled by the governor thru the engine oil, by means of a hollow crankshaft. A few older ones had a separate oil tank for the governor but went away with the use of a hollow crankshaft. They can be a pain in cold climates. Some pilots don't cycle the prop enough times prior to take-off to circulate the oil to get it warm. I don't know what type the new 912 uses. I suspect the electric type due to the gearbox being in the way, unless they use a oil feed line and a return line from the pressure port. Unless one has a definite need for one, they are not worth the trouble and they are pricey. A quick ground adjustable is almost as good. If one gets into a spot where changing pitch can get him out of, then spending 5 minutes changing the quick change pitch might suffice. Unless the grizzlies are chewing on your tail then the prop pitch might be the least worry!

[1avidflyer 1983]

The IVO constant speed unit is an electronic device that apparently monitors the rpm and pitch to adjust the prop pitch with the electric motor.  I have no experience with it though, but am curious.  JImChuk

ivoprop.com/inflightmediummodel.htm
ivoprop.com/constant.htm
 

[SuberAvid 617]

I am running the IVO Medium 3 blade with IFA but not the constant speed controller.  I have been running it on my Subaru for at least 5 or 6 years (would have to check the logbook) and have it on the Rotax 912 now.  It has been a great prop. I had the first motor fail within about 23 hours and sent it back, they rebuilt it and it lasted 12 hours so sent it back and asked them for a new one which they sent (all free of charge).  That one lasted about 600 hours before I had to replace it at a cost of about $200 with shipping.

I like the prop and it was a big improvement on the Subaru over the ground adjustable Warp Drive to get the max performance out of it.  It seems to work great on the Rotax as well but I don't have enough time on the combination to know where the best cruise settings are for fast or slow cruise yet.