Kiev prop adjustment

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Kiev prop adjustment

Postby Chief » Sat Oct 24, 2015 2:22 pm

My Highlander has been flying for a couple of weeks now in the Phase I test flight process. I have 10 hours on it. Testing reveals I'm getting 80 mph at 5000rpm. At 5400rpm I'm getting about 90mph. I'm running the Kiev 293. For you guys who have done this before, what adhustments do I need to make to give me a little better speed at 5400 but still have good climb performance and not exceed 5800 max rpm?
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Re: Kiev prop adjustment

Postby barry767 » Sun Oct 25, 2015 12:15 pm

My Highlander has 29" Airstreaks, extreme gear and a Kiev prop. I've got about 120 hours on it now. I started with the prop set more torwards the high pitch/low rpm setting then made 3 incremental adjustments, each time deceasing the pitch and increasing the rpm. I did this after talking with Troy who convinced me not to worry about running the engine right up to the rpm limit, at least on takeoff. The downside of this is, of course, is slightly higher fuel consumption and the need to guard against exceeding 5800 inadvertantly during criuse and descent. Your numbers seem pretty close to mine. You might try increasing the prop pitch just slightly to produce a little more speed at the same rpm. From memory, I think I get about 88 to 90 mph or so at 5300. My advice is to bias your final prop setting toward power (rpm), not speed. This airplane is all about having fun which to me means great takeoff/climb performance. You'll degrade this aspect of the Highlander if you're more intestested in IAS.
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Re: Kiev prop adjustment

Postby jjacky » Sun Oct 25, 2015 3:20 pm

So what pitch angle are you guys using now? I'm going to fire up the Rotax 912/Kiev 293 for the first time next week and need a starting point...Thanks!
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Re: Kiev prop adjustment

Postby barry767 » Sun Oct 25, 2015 4:47 pm

Don't remember off hand. I'll check tomorrow and get back to you.
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Re: Kiev prop adjustment

Postby Gil T » Mon Oct 26, 2015 12:09 am

I have the same prop and I just re-pitched it to 9 degrees. I get 2150 WOT at take off and 84 knots at 5100. My old setting of 10 degrees was giving me 1900 WOT and 87 knots at 5100. With the 9 degree setting I think I could have went past 5800 in level flight but I eased off when I passed 5700. There was a noticeable increase in takeoff performance and with just a loss of 3 knots I'm satisfied with it. Total time engine-635 hrs.

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Re: Kiev prop adjustment

Postby barry767 » Mon Oct 26, 2015 1:23 pm

Just checked my pitch. Like Gil's, it's also at 9 degrees. Seems to be the sweet spot!
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Re: Kiev prop adjustment

Postby Chief » Mon Oct 26, 2015 8:59 pm

Thanks for the responses guys.

My prop pitch is at 10. I think I will try 9 to see how it works.
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Re: Kiev prop adjustment

Postby av8rps » Tue Nov 03, 2015 4:39 pm

I fly a 912uls Highlander with a different prop, as well as a Kitfox with a 912 ul on amphib floats, and have found the 912 engines can still provide great climb power even with a more moderate cruise type of a pitch setting.

So I like to set my prop for a 5700 to 5800 rpm setting when straight and level and wide open throttle. At that setting my Highlander will cruise at a verified 108 mph at 5450 (with an open tube main gear with 8.50 tires), and yet will climb solo on a 72 degree day at 1,800 fpm. So I like to think my setting is good.

Regardless of the prop type (my kitfox has a 3 blade IVO and it acts much the same as the 2 blade Sensenich on my Highlander), I would use that 5700-5800 rpm number as described above. The only exception to that would be if I absolutely had to have the best STOL performance out of my airplane. But even with my prop set as described, I have incredible STOL performance. So I personally can't imagine needing more STOL than I'm getting ( It is already better than my buddies' 150 hp Super Cub). But my Highlander is less than 700 lbs, so that certaily helps too I'm sure...
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