R

R Eleew

Member
I am old school and like a manual trim wheel. Some folks swear by the electric trim, others say is overshoots very easily and you wind up flying the aircraft with the trim button.....

What are most of you all going with Manual or Electric?

Thanks for the great communication. The wealth of information on this site is incredible!

Rick Eleew
 
I put electric in my new 8 controlled by a cooly hat on the stick. It is nice to have control of both trims on the stick.
Chad H
 
I'm not "old school" because I've liked moving map GPS's since the early 90's! :)

I prefer electric trim, and preferred it on numerous other certified airplanes. You can always install a speed controller to slow the trim servos down.

The majority of all the RV's I've flown, have had electric. We must just like them around here.

I have a four way hat switch for elevator & aileron.

L.Adamson --- RV6A
 
Manual vs Electric

I have no idea what electric trim is all about - never had it in a plane. I ordered manual trims for both the elevators and ailerons. I believe the finite adjustments are better with manual trim and there's less expense, now and in the future, should something should go wrong. Then there's the possibility (however remote) of a runaway servo.

my $.02
 
Trim

Electric Trim controlled from a 4-way coolie hat on the stick. A little bump in any direction allows very small input changes. I have heard others talk about needing a speed controller to reduce the trim motor speed but I haven't found it necessary. The electric trim is also lighter and easier to install than the manual trim.

I installed trim and flap switches in the pilot stick. Nothing on the co-pilot side except a PTT. No secondary switch in the panel either. Lightweight super-simple installation.
Keith
RV9A
355RV
 
Trim

I have electric on mine, like Kieth said, a little bump and all is well. Better than sliced bread. And I am old school...
I just did a 5 hr cross-country last Thursday from Omaha to Atlanta and it is great to have.
 
I am going manual. I have never flown with an electric trim, so maybe I simply don't know what I am missing.
 
Manual

I went with manual trim in both places.

It is effective, simple, and reliable.

I have flown a few airplanes with defective electric trim and had to fall back to the trim wheel. The RV's electric trim doesn't have a manual backup, and for me this was another reason for the manual trim.

The manual trim is very effective and it doesn't take multiple twists of the pitch trim to trim it out.

And finally, try doing a search on the subject. This topic comes up about as often as the tail wheel - nose wheel discussion.
 
FWIW, I went with the manual because I have read where the electric can be touchy, plus I like the feel of manual stuff (would go with manual flaps if it were easy). Having said that, my installation is non-standard (I built a center console for throttle, mixture etc.) and the cable proved to be a bit of a pain to get routed properly (in my installation). It also uses up one set of holes in the tunnel that otherwise could be used for wiring.

greg
 
Good Article on Pitch Trim

Electric Pitch trim is nice, but runaway trim (however rare) can be really bad.

If you don't think so, go up, preferably WAY up, and do a test flight, and slowly trim to full up and down at various airspeeds, and see how she flies.

Also read: When Pitch Trim Systems Turn Ugly on Bob Nuckoll's web site.
 
I have a manual trim. Simple reliable and can't run-away. I'm not techno-phobic as the rest of the aeroplane is electric, I've just had trim run-aways on production aeroplanes and with the RV electric trim there is no manual reversion.

Only thing I found is if you have an RV7 or 9 with fuel injection get a RV8 cable so you can route around the fuel pump.

Peter
 
My .10

Whilst building my -6a, partner and myself acquired a flying -6a with electric trim.
This thing was so touchy, never being able to get it "just right" except by accident, not to mention the relays, curious wiring, etc., that I thought... "Let's go manual" on my project -6a. Did same, LUV it, never looked back... Much easier to get right. Methinks folks just like to have that "New, Modern" switch on the stick, like fighter jocks do...

Go manual on the trims, you will not be sorry.

MY dime's worth, thasall,

Jerry
 
Manual pitch and roll

trim on my -6 been working perfectly for over 15 years.
Of course I also have manual flaps too. And they have never failed me.
 
LifeofReiley said:
I sure would like manual flap in my 7... :)
Click to expand...
And I would like them in my -9 but Van's said there isn't enough leverage to lower the looooooong flaps I have. :(

My flap motor needs to be cleaned again as it is acting up for a 2nd time. I sure hope this doesn't happen every 75 hours!
 
I absolutely love my electric trim. I have Ray Allen servos on both the aileron & elevator and wouldn't want it any other way (tried both). The speed of the trim is perfect & quite easy to trim for hands off flight at any speed (no servo speed controller on my plane either).

For runaway servos, I tested my plane at full trim & found it to be controllable in any trim state. I do not have a trim power disconnect except for a fuse in my panel.

Still, it'll work either way & personal preference goes a long way. I say as many commonly used controls as possible should be on the stick though. Coolie hats & lots of buttons for all my friends!

Have fun!
 
QUOTE..
"I sure would like manual flap in my 7...
__________________
Darrell Reiley - VAF #671
RV 7A-QB Slider - Reiley Rocket II
N622DR Reserved - Finishing
Life is Good in Round Rock, TX"

Mel said:
with a little welding.
Click to expand...

And some parts from an RV12........??????????? Just might work.
 
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A couple of points rarely seeing the light of day in manual v. electric posts:

1. The Van's manual roll trim relies on friction to maintain set position. It can't accommodate much deflection, e.g., an imbalance of an hour's worth of fuel, without creeping back towards neutral. The servo locks the position you set. This problem is handled by fuel management.

2. Wiring! It's not just mechanical simplicity in favor of manuals. By the time you rig all the wires between servos, relays, indicators, switches, speed controllers, you don't need rivets to hold the fuselage together (sort of).

The electric pitch speed thing can be adjusted to your liking. I recommend making it easy to trim in cruise since a little goes a very, very long ways. Trim changes to slow in the pattern are really gross by comparison. Imperfect trim for maneuvering will not be missed. Lean on the button long enough to get you close.

John Siebold
Boise, ID
 
RV7ator said:
A couple of points rarely seeing the light of day in manual v. electric posts:

1. The Van's manual roll trim relies on friction to maintain set position. It can't accommodate much deflection, e.g., an imbalance of an hour's worth of fuel, without creeping back towards neutral. The servo locks the position you set. This problem is handled by fuel management.
Click to expand...
I have to respectfully disagree with this. I just completed some testing with full fuel in one tank ant the other empty and my manual roll trim holds fine.
 
Manual or Electric trim

R Eleew said:
I am old school and like a manual trim wheel. Some folks swear by the electric trim, others say is overshoots very easily and you wind up flying the aircraft with the trim button.....

What are most of you all going with Manual or Electric?

Thanks for the great communication. The wealth of information on this site is incredible!

Rick Eleew
Click to expand...

I have flown in RV's with both types of trim. Surprisingly, I liked the manual pitch trim more than the electric, but I like the electric aileron trim over the manual aileron trim.

The thing that impressed me about the manual trim was how incredibly easy it was to hit the "sweet spot" on the first try, IE, no chasing of altitude.

Just my two cents. Both systems are satisfactory. Having the trim on the stick is a nice convenience as well.

YMMV,
JP
 
Please provide a more detailed explanation...

Mel said:
with a little welding.
Click to expand...

of how to convert a -7 back to manual flaps. I know many think that there isn't enough room between the occupants. Has anyone considered a compound system that could reduce operating force and move the flap lever forward?

I own a Cherokee w/ manual flaps, which I like much better than the electric flaps in all the Cessnas I flew before that. I was surprised and disappointed when I inventoried my -7 kit and found out electric flaps were standard, period.

Larry
 
LarryT said:
of how to convert a -7 back to manual flaps. I know many think that there isn't enough room between the occupants. Has anyone considered a compound system that could reduce operating force and move the flap lever forward?
Click to expand...
Find someone who has a set of -6 plans and follow the installation. The lever will have to be cut and re-welded at a different angle. The -6, -7 and -9 all have the same distance between the seats.
 
LarryT said:
I own a Cherokee w/ manual flaps, which I like much better than the electric flaps in all the Cessnas I flew before that. I was surprised and disappointed when I inventoried my -7 kit and found out electric flaps were standard, period.
Click to expand...

Manual flaps are going to be the easy part. I definitely want to see pictures if you go with a Cherokee style overhead crank for pitch trim in your 7 :D
 
The manual flaps are great. No need for making a lever with a mechanical advantage. If you can't pull them on then your airspeed is too high.
 
I would love to have manual flaps in a -9. Wasn't there some discussion a while back that the actuation force might be impractical with the 9's larger flaps?
 
Electric vs manual trim

I am going with manual trim. I like the KISS theory. Electric trim has buttos,wires,wire terminals,brushes,fuses all of which can fail. Im an electrical engineer so that is what I look at.
 
groucho said:
For runaway servos, I tested my plane at full trim & found it to be controllable in any trim state. I do not have a trim power disconnect except for a fuse in my panel.


!
Click to expand...
All of us should test our aircraft at full trim positions during that 40 hours of testing we all do. What you'll find is that full trim either direction is controllable, and even more so if you reduce power a little. The electric trim setup works fine and has a long service history.
 
RV-7 manual flaps

Mel said:
Find someone who has a set of -6 plans and follow the installation. The lever will have to be cut and re-welded at a different angle. The -6, -7 and -9 all have the same distance between the seats.
Click to expand...

Mel, are you referring to the "torque tube." If so, could one possibly purchase an RV-6 torque tube as a service part, i.e., would it mount in the pillow blocks and connect to the flaps exactly as the -7 kit supplied part.

If the above is the case, I would do that and offer the flap kit and torque tube for sale to a -6 builder who does want electric flaps.

Larry
 
Electric or manual elevator trim

I have used both and I have manual in my present aircraft, but I am installing the electric in my 9A. I will go w/manual on the ailerons. I also prefer manual flaps, but that choice is not there.
 
I've actually got a slightly different take on this.

I plan to go electric, but, I do plan to use the "split" style controller that the cessnas use (if you haven't seen this, its a "split" switch and you need to slide both halves to activate the flaps), where you need to press both buttons coupled to a controller for the servo. In the case that the motor is running and both buttons are not pressed, then the system controller cuts power to the servo.

Obviously, this is not foolproof (both switched could simultaneously fail), but it does add a watchdog to trim runaway.

As for the mechanical crank -- I loved the ceiling mounted crank in the old cherokees. If I could figure out a way to mount one in the -9 I'd do it. You could actually have a mechanical wheel on electric trim. Simply use an decent encoder (grayhill, etc) coupled to the physical wheel. Then build a simple motor controller out of a PIC, PICAXE, ATMEGA, Parallax (you could even use a "propeller" chip), etc and you have "fly by wire" trim control.
 
The dimensions are different.

LarryT said:
Mel, are you referring to the "torque tube." If so, could one possibly purchase an RV-6 torque tube as a service part, i.e., would it mount in the pillow blocks and connect to the flaps exactly as the -7 kit supplied part.
If the above is the case, I would do that and offer the flap kit and torque tube for sale to a -6 builder who does want electric flaps.
Larry
Click to expand...
If you use the -6 torque tube, the pillow blocks will mount in "front" of the bulkhead instead of behind it.
 
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