| czechsix |
04-16-2017 02:11 PM |
Quote:
Originally Posted by TimO
(Post 1165359)
I always find it interesting when people talk about wanting to get less weight on the nose. The RV-14 isn't nose heavy at all, and I actually was even glad to have changed out my starter knowing the new one was 1 lbs heavier. The aerobatic CG range isn't really all that wide, and I find that I have to think about my loadings a bit to ensure I stay forward enough CG for things like that. If anything, I've been thinking that maybe it would have been nice to have the ELT not mounted in the tail but mounted right behind the baggage area just to move more weight forward.
So I personally think trying to adjust the plane by making the engine or prop lighter is likely to be a mistake. There's not much you can play with in the back end to make lighter as well, to keep your CG as far forward as possible.
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Tim,
Good points about CG. My desire to use a composite prop isn't to reduce weight on the nose per se, but an overall lighter airframe improves performance, and there are other benefits of the composite prop (namely smoother operation and the Whirlwinds don't seem to have the problems with slinging grease that Hartzells do...been there, done that, don't want to do it again). I've done the math using several W&B samples and have a couple posts in the sticky thread on CG/W&B. If you move the ELT to the baggage compartment, get rid of the aft ADS-B antenna (using a Garmin GTX345 give you both transponder and ADS-B In/Out functions with one antenna & coax run), and keep primer/paint/fiberglass application light in the empennage I think you offset the CG shift due to the lighter prop almost completely (and save a few additional pounds in the process).
It would be great to have real numbers from a -14A with composite prop, maybe Carl and Rafael can post theirs sometime (although I think their Hartzell composite prop may be a bit heavier than Whirlwind's).
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