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  #1  
Old 05-28-2012, 03:55 PM
Flyin4Fun Flyin4Fun is offline
 
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Default Advantage of electric trim

Are there any advantages to electric elevator trim that justify the added cost and added aft CG weight?
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  #2  
Old 05-28-2012, 04:23 PM
hayabusa hayabusa is offline
 
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I thought the electric trim was lighter than the manual cable assembly?
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Old 05-28-2012, 05:02 PM
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ChiefPilot ChiefPilot is offline
 
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Quote:
Originally Posted by Flyin4Fun View Post
Are there any advantages to electric elevator trim that justify the added cost and added aft CG weight?
Aside from being lighter as previously mentioned, the electric trim also preserves pass through space in the spar box - the manual trim cable is thick; the 22g wires for the electric trim are tiny in comparison. Depending on how you equip your plane, space to pass wires through the spar box may be very valuable.
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Old 05-28-2012, 05:04 PM
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Vlad Vlad is offline
 
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Quote:
Originally Posted by Flyin4Fun View Post
Are there any advantages to electric elevator trim that justify the added cost and added aft CG weight?

Right question. Take monetary difference between the two and divide it by $5.80 then figure out how far your RV can reach for that difference. As you see there is no advantage.
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Old 05-28-2012, 05:06 PM
pilottangocharlie pilottangocharlie is offline
 
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There could definitely be an advantage to the resale value of your airplane.

I hear it can add 5 knots to your cruise speeds and 100fpm in sea level climb speed at Vx.
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  #6  
Old 05-28-2012, 05:19 PM
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Jamie Jamie is offline
 
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Practical benefit of electric trim is HOTAS ergonomics. Downside is more parts count. If I had to do it again I would probably just put electric trim on the pilot's side. Wiring trim to one set of switches eliminates the need for relays (if your switches are rated for the draw of the motors which I believe most are).
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  #7  
Old 05-28-2012, 06:59 PM
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Vern Vern is offline
 
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Default Electric Trim

In formation and Instruments, an electric trim is very handy. Note that most military jets had the electric trim actuated on the stick, typically via a 'coolie hat switch.'
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  #8  
Old 05-28-2012, 08:50 PM
Charles in SC Charles in SC is offline
 
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I went with manual because in the planes that I have flown with electric trim (more than 10) I always wound up needing to use the manual wheel in cruise flight. I found it to be more able to fine tune the trim. On an rv you do not have a manual wheel at the same time as an electric thing.
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Old 05-28-2012, 10:09 PM
RV7ator RV7ator is offline
 
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The manual pitch trim cable is a loopy thing that just takes up more foot room. How you'd snake it past a typical FI pump in the same area I don't know since I've always had carbs. The mounting tab is one more edge to dent your lower leg. It does work well, though.

Consider splitting the difference and use electric pitch and manual roll trims. Mount the switch/annunciator on the panel close to the throttle and perhaps the flap switch. You can still keep a hand on the throttle and work trim/flaps with your thumb - just like texting! - and you save the cost and complication of relays and wiring to the stick. It's also accessible for the FO.

John Siebold
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  #10  
Old 05-28-2012, 11:19 PM
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MauiLvrs MauiLvrs is offline
 
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Quote:
Originally Posted by RV7ator View Post
Mount the switch/annunciator on the panel close to the throttle and perhaps the flap switch.
Or on the stick....
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