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Question: Vernier vs. Quadrant vs. Combo?

1001001

Well Known Member
Here is a question I never thought I'd find it necessary to ask. I always assumed I was going to put in a quadrant engine control set in the RV-10. I was used to using the quadrant with my old Warrior, and never having flown a vernier-controlled airplane, just assumed I liked it best.

However, since I bought my Mooney 201, I have been very pleased with the fine control available with the verniers on propeller and mixture. My 201 has a non-vernier push-pull throttle with a concentric ring friction lock.

I'm not sure I'd be able to lean with the same precision with a quadrant mixture control that I'm able to with the vernier. Also, the vernier seems to offer better stability against drift due to vibrations, cable tension, etc. I never did any precision leaning with the Warrior, since it didn't have adequate engine instrumentation and was carbureted. I experienced some minor control drift with it, as the friction lock was well worn.

I really think I still prefer the quadrant for the throttle control (I plan on flying the RV like I fly the Mooney--wide open throttle pretty much all the time), but may consider vernier controls for the mixture, and possibly the prop. I could do this by using a two-lever quadrant control for throttle and prop, and installing a push-pull vernier in the panel for mixure.

I can think of some pros and cons to this approach:

Pros:
Finer control of the mixture and possibly engine speed.
Better resistance to control position drift in flight
?

Cons:
Not all engine controls consistent with each other
Not all engine controls in one place
Not standard to any other aircraft
Effect on resale value (hopefully not an issue for a long time, but still...)

What say you?
 
For the RV-10 I recommend not installing a quadrant (as in just stay with push/pull controls). A quadrant takes up too much room and provides no advantage - other than the look if that is what you are going for.

I also recommend vernier prop and mixture, but never vernier throttle. I flew one plane with vernier throttle and hated it. Add to that your point about tending to always be at WOT anyway. The RV-10 likes high and WOT/LOP - just balance the injectors.

Carl
 
For the RV-10 I recommend not installing a quadrant (as in just stay with push/pull controls). A quadrant takes up too much room and provides no advantage - other than the look if that is what you are going for.

I also recommend vernier prop and mixture, but never vernier throttle. I flew one plane with vernier throttle and hated it. Add to that your point about tending to always be at WOT anyway. The RV-10 likes high and WOT/LOP - just balance the injectors.

Carl

I am coming around to this way of thinking. For a long time I wanted to have the throttle control at my side, with it being easy to reach. I don't like having my arm hanging way out there just to keep it on the throttle at critical phases of flight. But now I'm not so sure that the trade-off for more space in the center console for something like a drink holder and pockets for pens/notebooks/etc. wouldn't be better.

Anyone have more thoughts on the mixing of push-pull and quadrant controls?
 
+1 for the McFarlane vernier throttle. It has a friction ring to adjust tension, push pull without having to press a central button, and fine adjustment by rotation.
 
Did my commercial rating in a Mooney with a vernier throttle and hated the throttle. When a go-around was needed, there was time delay getting full power. Never found a need for precise manifold pressure setting that a vernier throttle could provide.

WHY is a vernier throttle needed on an airplane?

Typically on a real Total Performance airplane with a constant speed prop, set manifold pressure with the friction lock throttle and use vernier on the prop plus mixture to fine tune power output.

I have seen an RV-8 with typical friction throttle and vernier mixture / prop. Thinking about doing the same for my RV-8 project but may go the way the majority of RV-8s are configured.
 
+2 for the McFarlane vernier throttle. As Keith mentions it has a friction ring not a locking knob. Also Have the McFarland prop and mixture control, these have the position locking knob. Stein Aviation has a nice vernier bracket That mounts under the bottom edge of the panel.
 
here's our 10 year experience, although not on a -10 but a -7A.

we modified/relabeled a 2-lever DJM mfg throttle/mixture quadrant to use it for throttle and prop in a custom center console.
for the mixture, used a locking vernier from aircraft spruce on a separate location in a subpanel, near the fuel selector (also in a custom raised location).
best of both worlds (fine control on mixture and great ergonomics on throttle/prop). would definitely do it again this way and the "uncommon" split of mixture from throttle and prop is zero problem, even for other pilots that transitioned to our plane...
now that i do lots of formation flying (may not matter much on a 10), being able to partly rest your throttle hand on the console and in a convenient position is worth gold!

ymmv.

i hope things improved (pdf spec sheets?), but at the time, all these various control cable products had poorly documented and very differing ends (throw length, distance of mounting thread from rod end, diameter of mounting thread etc...) which was a pain to come up with the right brackets and ordering the correct custom lengths. if you want least trouble and maximum build speed, sticking tightly to van's maybe at the cost of maximum ergonomy will pay off.
the only two downsides of the custom center console so far is a little bit of extra weight and some movement restrictions during maintenance below the panel / fwd fuselage.
 
here's our 10 year experience, although not on a -10 but a -7A.

we modified/relabeled a 2-lever DJM mfg throttle/mixture quadrant to use it for throttle and prop in a custom center console.
for the mixture, used a locking vernier from aircraft spruce on a separate location in a subpanel, near the fuel selector (also in a custom raised location).
best of both worlds (fine control on mixture and great ergonomics on throttle/prop). would definitely do it again this way and the "uncommon" split of mixture from throttle and prop is zero problem, even for other pilots that transitioned to our plane...
now that i do lots of formation flying (may not matter much on a 10), being able to partly rest your throttle hand on the console and in a convenient position is worth gold!

ymmv.

i hope things improved (pdf spec sheets?), but at the time, all these various control cable products had poorly documented and very differing ends (throw length, distance of mounting thread from rod end, diameter of mounting thread etc...) which was a pain to come up with the right brackets and ordering the correct custom lengths. if you want least trouble and maximum build speed, sticking tightly to van's maybe at the cost of maximum ergonomy will pay off.
the only two downsides of the custom center console so far is a little bit of extra weight and some movement restrictions during maintenance below the panel / fwd fuselage.

Any chance you could post some pictures of your setup? This sounds pretty much like what I'm thinking about mixed controls.
 
i only find two older pics right now,
will have two make more recent ones. there were a few changes in the radio stack, pc keyboard and such minor stuff.
p1040660.jpg

img_4302.jpg


as mentioned, ergonomics are top. and one can precisely lean the engine.
 
i only find two older pics right now,
will have two make more recent ones. there were a few changes in the radio stack, pc keyboard and such minor stuff.

as mentioned, ergonomics are top. and one can precisely lean the engine.

Thank you for the pictures!
 
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