Replacing Vernier controls with friction

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rv8bldr
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Post by rv8bldr »

DeltaRomeo wrote:I believe the original poster is speaking of vernier throttle (but did't specifically say that).

I have flown Maules with vernier and friction throttles; I don't like the vernier for a throttle. Much prefer a friction for the throttle but vernier is necessary for prop and mixture. A vernier mixture control is hard to get into the tight panel location without interfering with flight controls.
The last owner of my M5-235C never moved the bowden cable based mixture control thus it was almost impossible to use. I was afraid the cable was going to break every time I tried to change the mixture.

I had a local maintenance shop replace the original mixture cable with a vernier from ACS. I hadn't considered the interference problem but they discovered it during installation. They just used a wedge washer arrangement that points the mixture control more towards the pilot side. Works great and no interference.

https://www.mcfarlaneaviation.com/produ ... duct/EC89/

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Mark
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'79 Maule M5-235C C-GJFK
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DeltaRomeo
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Post by DeltaRomeo »

"The last owner of my M5-235C never moved the bowden cable based mixture control thus it was almost impossible to use."

Another thing to consider here is the ground cable from the engine to the mount: if the cable crimps become loose, it makes for a questionable ground circuit for the starter. With that, the starter being a high amp draw accessory, other items will provide the return path to the battery, such as any control cable attached to the engine: Throttle, Mixture, etc. These cables will conduct the current the starter is unable to get from the ground cable and as such may "weld" themselves into a dysfunctional condition. Moral of this story is ensure your ground cable is in good condition.
M5

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LCDRLES
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Post by LCDRLES »

I’ve got vernier throttle on M5 and friction throttle on C180.
Never seemed liked too big a deal which one I use.
The difference in the elevator trim between the two is what causes me problems. My Maule trims easily without a lot of trim wheel movement. The C180 trim like steering a ship. Lots of wheel movement. The 180 can become a handful on a steep approach, short field go around trimmed for approach with full flaps.
The Maule is much easier to handle in the same situation.
1984 M5 180C, N5654B
1956 Cessna 180, N4971A
1977 7GCAA, N1165E

plowboy
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Post by plowboy »

LCDRLES wrote:I’ve got vernier throttle on M5 and friction throttle on C180.
Never seemed liked too big a deal which one I use.
The difference in the elevator trim between the two is what causes me problems. My Maule trims easily without a lot of trim wheel movement. The C180 trim like steering a ship. Lots of wheel movement. The 180 can become a handful on a steep approach, short field go around trimmed for approach with full flaps.
The Maule is much easier to handle in the same situation.
to keep all the elevator authority you can have, trimming on a Maule is something I do not do on the approach. I take Jeremey's advice and just muscle the elevator during the approach. But that is just me, the super cub with the flying tail does not have this issue.

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andy
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Post by andy »

Elevator trim on the Maule is the relatively small trim tab on the left elevator. It's not hard to do because there's not a lot of air pressure against the tab. The C185 that I fly for work moves the entire horizontal stabilizer for elevator trim so it's a bear to move, especially at high airspeed. I've found that pitching up or down in the opposite direction while you move the trim wheel takes some pressure off the horizontal stabilizer and allows much easier trimming.

I also use Jeremy's recommended procedure of applying no elevator trim during landing with the Maule. That gives you full elevator control during the entire approach. You can't do that with the C185 though. Pitch changes radically with the application of flaps and if you don't trim out the control pressure, fighting the elevator would tire you out quickly.
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zamfire
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Post by zamfire »

Mine has Vernier for throttle and friction for mixt; the exact opposite of what makes sense. I damn near kill the engine with my gritty , sticky mixture control, I hate it.


Just fit whatever you feel works best. And before you start asking for "approved" and STCs, please read 14 CFR Part 1.1. There is considerably more latitude in what you can alter or modify than most A&Ps will tell you.

I'm going to change mine out with a logbook entry, that is all. Because it does NOT:

"(1) ....appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness; or

(2) That is not done according to accepted practices or cannot be done by elementary operations.


It's as simple as that.


Warning - I will be quoting this all over the place and incur the wrath of many an A&P and IA, but the language and intent is clear. Mike Busch concurs.
1965 M-4 Jetason, O-300 Ser.no 089. Flabob CA.

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gbarrier
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Post by gbarrier »

Ours had vernier when we bought it. Hated it and replaced with friction which is just fine. Since have flown other Maules to find that our vernier was just worn out. Had no problem with verniers on other people’s airplanes. May go back to it. As far as installing the vernier mixture on airplanes which does not have one look at the drawings and move everything one hole to the left like you are suppose to. Also, use the wedges shown there so the cables tilt up and clear everything behind the panel. Also, think there is a backing plate involved. Do it right.

Maule has been good to us with the drawings on parts DCs. Things that happen on later models can usually be adapted to the early ones but you don’t always just stick it in there. Chances are there is a drawing for that.

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