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  • Re: In flight adjustable Ivoprop for 912UL?

    by » 2 years ago


    Jim Isaacs wrote:

    Down Roger! Bad Roger! Stop barking at the guests! 

    Not barking and I don't even grow if someone puts their hand near my food. LOL

    . Just asking questions to see what might be the best option and to see if his aircraft was legal with an in flight adjustable prop. Some aircraft in the US vs other countries can make or break a deal like the in flight adjustable prop. Sometimes you just need more of the story to help fellow pilots solve problems. There are better props out there than Warp and add in flight capability and his aircraft performance would be greatly improved. I think his idea about an IVO in flight adjustable prop is a fairly good idea. He would see a marked performance increase.


    Roger Lee
    LSRM-A & Rotax Instructor & Rotax IRC
    Tucson, AZ Ryan Airfield (KRYN)
    520-349-7056 Cell


  • Re: In flight adjustable Ivoprop for 912UL?

    by » 2 years ago


    I can recommend  Fiti - they just seem to be an excellent match for Rotax 9 engines.

    Very quite & smooth operation delivering all the thrust the Rotax can put out.

    Available in fixed, ground adjust, in flight adjust and 2-3 blade.

    Don't know if they can be purchased direct - I got mine from ATEC aircraft


  • Re: In flight adjustable Ivoprop for 912UL?

    by » 2 years ago


    The Fiti looks nice, but not much info on it.  The diameter is 62" for the 80 HP, which would be too big for me.  Likely I don't want to know the price. 

    I'm still a bit new with the 912 engine, and I see that it presents more of a challenge for fixed pitch props than Ly/Conts.  Max power is near the 5800 RPM limit, but since that limit is only allowed for 5 min, 5500 becomes the full time limit.  This creates an even larger range of pitch that you'd need for ideal operation.  Even with the Warp Drive pitched for optimum cruise, I'll still likely have plenty of climb, so I'm not sure it will be worth the added complexity, but I can't help considering it.

     


  • Re: In flight adjustable Ivoprop for 912UL?

    by » 2 years ago


    RUSSELL A DUFFY wrote:

    The Fiti looks nice, but not much info on it.  The diameter is 62" for the 80 HP, which would be too big for me.  Likely I don't want to know the price. 

    I'm still a bit new with the 912 engine, and I see that it presents more of a challenge for fixed pitch props than Ly/Conts.  Max power is near the 5800 RPM limit, but since that limit is only allowed for 5 min, 5500 becomes the full time limit.  This creates an even larger range of pitch that you'd need for ideal operation.  Even with the Warp Drive pitched for optimum cruise, I'll still likely have plenty of climb, so I'm not sure it will be worth the added complexity, but I can't help considering it.

    Yeah...Nah

    Not true the prop sees depending on gear ratio (2.27 or 2.43) 2555 or 2422 rpm at engine rpm of 5800 and 2386 or 2263 rpm at 5500 engine rpm.

    Soooo the difference between 5800 and 5500 is only 123-132 rpm at the Prop...

    My old Flight Instructor in the Tommy said max rpm 2700 max at climb 2400 rpm so a difference of 300 rpm

    !!!


  • Re: In flight adjustable Ivoprop for 912UL?

    by » 2 years ago


    RUSSELL A DUFFY wrote:

    The Fiti looks nice, but not much info on it.  The diameter is 62" for the 80 HP, which would be too big for me.  Likely I don't want to know the price. 

    I'm still a bit new with the 912 engine, and I see that it presents more of a challenge for fixed pitch props than Ly/Conts.  Max power is near the 5800 RPM limit, but since that limit is only allowed for 5 min, 5500 becomes the full time limit.  This creates an even larger range of pitch that you'd need for ideal operation.  Even with the Warp Drive pitched for optimum cruise, I'll still likely have plenty of climb, so I'm not sure it will be worth the added complexity, but I can't help considering it.

    Glen is on the right track - pilots trained/experienced on direct drive engines tend to think in engine = prop RPM.

    Rotax geared engines do not have the same easy engine speed:prop speed relationship.

    My ATEC Zephyr / Rotax 912 ULS, fitted with two blade Fiti (ground adjust), set to about 19 degrees pitch, gave 5200 static RPM. This gave the aircraft a sub 100m ground role on grass, easy 12000ft/min climb out (5800RPM). Under 13L/hr fuel burn at 100 knots  (5200 RPM) and about 18L/hr burn at 120 knots (5500 RPM sea level). Stooging aground, 60-80 knots, about 8 l/hr.

     

    The current ATEC price for the Fiti two blade, ground adjust, is 1,672 Euro (about $ 1,757US)


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