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Engine Controls: Push-Pull vs Quadrant

1001001

Well Known Member
For the longest time, I assumed I was going to build my RV-10 with a throttle quadrant. I learned to fly in a Warrior II that had a quadrant, and flew that airplane well over 300 hours and never got to really use push-pull controls until I bought my Mooney 201 a couple of years ago.

I really really liked the look and idea of the Aerosport tunnel-mounted-console quadrant, and planned to incorporate it into my airplane. However, since I have been flying the Mooney, I have come to like the push-pull controls. In that airplane I have a friction lock throttle and vernier style prop and mixture controls. I have gotten used to it, and think I actually prefer it to the quadrant now.

Now that I'm thinking about it, I feel like the push-pull controls will take up a lot less space and reduce complexity in the installation process. I still plan to use Aerosport's center console and panel (which one, I'm not certain of yet) and I think using the push-pull will be simpler and work just as well in the airplane as the quadrant would.

Any thoughts? I'm really not leaning one way or the other anymore, but think the smaller space requirements of the push-pull and reduced installation complexity are winners here.

What do you think?
 
I've flown both extensively and never ended up with a distinct preference. I do like the vernier capability that push-pull gives me for prop and mixture.
 
I should add that I have flown a friend's RV-10 (from the right seat) with a quadrant that is mounted up near the control panel, and it feels mostly like the Warrior did, which is fine. But the quadrant still takes up quite a bit of space in that area too.
 
I have flown a bit with quadrants, but much prefer the push pull. I am always tinkering with mixture to achieve efficiency and suspect that it is much easier to make precise adjustments with a vernier knob. No brainer decision for my style. Not having a quadrant allowed me to put a large fire extinguisher on top of the tunnel, where it is easy to reach in an emergency, yet mostly out of the way.

Larry
 
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I have flown a bit with quadrants, but much prefer the push pull. I am always tinkering with mixture to achieve efficiency and suspect that it is much easier to make precise adjustments with a vernier knob. No brainer decision for my style. Not having a quadrant allowed me to put a large fire extinguisher on top of the tunnel, where it is easy to reach in an emergency.

Larry

I agree with this!
 
Another question:

For those of you who have installed the Aerosport panels with push-pull controls, do you find that the panel is stiff enough or does it flex much when operating the controls? Do they get mounted directly to the carbon fiber panel or is there aluminum structure behind the panel that they have to be fastened to?
 
ever seen a fighter or airliner with push-pull controls? And why not?

Gotta get that popcorn popper out now 🍿
;)
 
ever seen a fighter or airliner with push-pull controls? And why not?

Gotta get that popcorn popper out now ��
;)

Not really relevant. Ever seen a fighter or airliner with a piston engine and constant speed prop? Assuming you mean more modern stuff from the last 60 years, of course.
 
I've got the levers in my RV-8, and if I were doing it again, I'd do it with one throttle lever, and vernier cables for the prop and mixture. You get much finer control with the vernier cables, and my AFP FM200 has about 6" of full travel on the lever, and I spend most of my time either full rich for takeoff, or in about 1/4" of the whole throw at a position of about 2.5".

The prop is very linear, and is easier to fine tune, but a vernier would make that easier too.

I read this advice from several builders on this site, but unfortunately didn't listen.
 
4000 hrs with quadrants. The 14 is the first plane I flew with push pull and I must say I love it. As mentioned previously the fine vernier control for the prop and mixture is really nice.
 
Another question:

For those of you who have installed the Aerosport panels with push-pull controls, do you find that the panel is stiff enough or does it flex much when operating the controls? Do they get mounted directly to the carbon fiber panel or is there aluminum structure behind the panel that they have to be fastened to?

The aerosport panel does not move a bit with the push pulls. It’s backed by an aluminum plate that is well supported in multiple places

Mine “mount” directly to the carbon fiber but there are adel clamps supporting the cables right behind the panel that hold things in place.
 
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I went for more leg room, simple system, and wanted to keep weight down. I did not go with the Aerosport set up for those reasons. If those are not factors and you want that sports car feel, the full Aerosport package will give you that. I’m more of a SUV type. If you go with push/pull I recommend the Vernier-Assist for the throttle, prop, and mixture control specifically from McFarlane aviation. They have ones already specifically made for the -10.
 
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I went for more leg room, simple system, and wanted to keep weight down. I did not go with the Aerosport set up for those reasons. If those are not factors and you want that sports car feel, the full Aerosport package will give you that. I’m more of a SUV type. If you go with push/pull I recommend the Vernier-Assist for the throttle, prop, and mixture control specifically from McFarlane aviation. They have ones already specifically made for the -10.

Not sure I want a vernier on the throttle--I'd prefer it to be as free-moving as possible. Or is that a different type of cable?

EDIT: Oh, I see, just looked them up. Interesting that they can make a vernier style that can be pushed/pulled without disengaging a lock.
 
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Not sure I want a vernier on the throttle--I'd prefer it to be as free-moving as possible. Or is that a different type of cable?

EDIT: Oh, I see, just looked them up. Interesting that they can make a vernier style that can be pushed/pulled without disengaging a lock.

If you ever plan to let someone else fly your plane, I strongly suggest a traditional throttle cable. If I need power in the flare, I need it now. Not a good time to be reminded that you must push a lock button first. Decades of habit will ensure that the new pilot will just push in a crisis. By the time he figures out the lock button, it could be too late.

Larry
 
If you ever plan to let someone else fly your plane, I strongly suggest a traditional throttle cable. If I need power in the flare, I need it now. Not a good time to be reminded that you must push a lock button first. Decades of habit will ensure that the new pilot will just push in a crisis. By the time he figures out the lock button, it could be too late.

Larry

According to their marketing material on the web site:

McFarlane’s patented Vernier-Assist™ offers the pilot precision control of the engine, unlike anything else on the market! The Vernier-Assist assembly operates on friction alone by simply turning the knob, with no threads or locking balls/pins. It also allows for normal coarse movement by pushing in or out on the knob. Unlike standard threaded vernier controls, this design cannot be jammed. The friction control provides smoothness and precision when operating the throttle and a friction lock secures the control in position, but it can be easily overridden in the case of an emergency. It is SAFE!

What are others' experiences with the product?
 
Its great!

According to their marketing material on the web site:



What are others' experiences with the product?

I had this on my previous -9A and have installed one on my current -14A build. It works great - it function just like a traditional push pull throttle, with the added benefit of being able to fine tune the throttle to get the exact setting desired. I wouldn't go back!
 
This is the first I've heard of the vernier-assist cable. It sounds OK but I don't find fine tuning the throttle a real issue with a traditional cable since for most of the flight it's never moved from WOT. When I am ready to reduce power, I've never had a problem hitting the MP I want for the performance I'm trying to achieve. IMO it's kind of a solution in search of problem, especially if it costs more. YMMV....
 
This is the first I've heard of the vernier-assist cable. It sounds OK but I don't find fine tuning the throttle a real issue with a traditional cable since for most of the flight it's never moved from WOT. When I am ready to reduce power, I've never had a problem hitting the MP I want for the performance I'm trying to achieve. IMO it's kind of a solution in search of problem, especially if it costs more. YMMV....

That's kind of my thought. Flying the Mooney, the only time I'm not at WOT is if I'm practicing maneuvers or doing sightseeing, neither of which require precise setting--they are done by feel, checking the numbers. When I'm going cross country, its WOT-LOP.
 
Engine Controls: Push-Pull vs Quadrant

According to their marketing material on the web site:

What are others' experiences with the product?

I have the McFarlane lockable vernier throttle and like it a lot - works great, gives you the ability to do quick push-pull throttle changes as well as vernier adjustments.

One additional observation, regarding push pull controls and McFarlane. I originally had the very common ACS controls, such as available through Spruce and others. My throttle cable broke at the swivel point near the fuel servo, due to what I eventually determined to be a deficient design - work hardening of the cable where it is crimped into the swiveling piece. Resulted in an emergency landing with no throttle control. Replacement put me on the McFarlane path, who's cables are far more rugged and well designed. Ended up replacing all three of my cables with the McFarlane ones. And they do a nice job of getting you whatever length you need. A bit more expensive though.
 
I went for more leg room, simple system, and wanted to keep weight down. I did not go with the Aerosport set up for those reasons. If those are not factors and you want that sports car feel, the full Aerosport package will give you that. I’m more of a SUV type. If you go with push/pull I recommend the Vernier-Assist for the throttle, prop, and mixture control specifically from McFarlane aviation. They have ones already specifically made for the -10.

Just be aware that if you DO go for the Aerosport panels and the Mcfarlane cables, you will need to add some length to the cables as location of the attach point is different than the regular Vans panel.
 
The McFarlane throttle does not have a release button. It has a throttle friction adjustment only. You do not have a release button like on the prop and mixture control. You do have the ability to twist in and out on the throttle for adjustments just like the prop and mixture. I have a flat panel the Stein did for my panel. As mentioned in the above post (good catch) you will need slightly longer (I believe an inch or two) which McFarlane will make on request.
 
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One comment on the AeroSport quadrant mounted on the tunnel just forward of the arm rest. I installed this on my RV-10 and like the look and feel of it. But once a year at Condition Inspection time, I don't like it much. I find it makes it much harder to remove the tunnel cover and perform the required inspections in the tunnel.

Just another data point.
Happy Holidays
 
I like mine mounted just below the aeorsport fiberglass panel. A natural position for me, and my hand is close to the glass should I need to change a view on it.
 
I'm doing a combination. Quadrant for throttle/prop. Mixture will be Vernier (more likely EFI).

Reason is during a go-around or any need for power NOW, I can push the mixture forward then both throttle and prop levers go up at the same time. Vernier allows for fine tuning of mixture (EFI does too).
 
One comment on the AeroSport quadrant mounted on the tunnel just forward of the arm rest. I installed this on my RV-10 and like the look and feel of it. But once a year at Condition Inspection time, I don't like it much. I find it makes it much harder to remove the tunnel cover and perform the required inspections in the tunnel.

Just another data point.
Happy Holidays

That's my primary concern with that. I really liked the idea, but over time, have cooled on it based on the installation/inspection complexity and my positive impression of the push-pull controls in my Mooney.
 
RV-10 quadrant

I have flown RV-10 with and without the quadrant. The one with the quadrant is nice but does take up a lot of leg room. I noticed that I could not get full aileron deflection when moving the controls in the direction of the quadrant because the stick hits my leg which is against the quadrant. With a passenger in the right seat I could not get full deflection in either direction. I recommend sitting in an RV-10 with and without the center console/quadrant and try it before you decide.
 
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