Feasible and practical to fit vernier throttle to an M20J?

[jtager]

I know that a version of this question has been posted before, but there wasn’t a definitive, usable response at the time.  My inquiry is as follows: is it feasible and practical to fit a vernier throttle to an M20J, and if so, how?  I discussed this with the engineer that looks after my (South Africa-based) J, and I understand from his response that simple fitment would not be a problem, but that given the J uses the existing throttle cable / mechanism to activate the gear warning system (as opposed to on the Ovation and its vernier throttle for example, where the gear warning activation mechanism is triggered elsewhere on the Continental motor), one would need a workaround of sorts to create the warning mechanism on the J. I’d rather avoid a custom field modification, so if there’s a McFarlane (or other) product that would legally do the job ‘off-the-shelf’ and unmodified, I’m keen to know about it.  This is something I’d asked about and given up on a while back, but the impetus for my question is that I found a photograph online of a new panel in a ‘79 J (N3774H), boasting a G500TXi display and clearly sporting a vernier throttle. If the owner or operator (or someone else in the know) of the aforementioned J sees this post, I’d be delighted to hear from you.  Any other usable advice would also be greatly appreciated.  

Edited May 2, 2021 by jtager
Improved clarity of wording.

[ArtVandelay]

Yes, I have one on my J, I replaced all control cables when I overhauled the engine:



I sent them my old cable to use as template.

[jtager]

Thanks so much for the prompt response.  So, I infer that you sent your old cable to McFarlane and they returned a version of their product that still provides you with the requisite gear warning activation?  Am I correct?  If so, what sort of paperwork is involved?  What model year is your J?

[ArtVandelay]

Thanks so much for the prompt response.  So, I infer that you sent your old cable to McFarlane and they returned a version of their product that still provides you with the requisite gear warning activation?  Am I correct?  If so, what sort of paperwork is involved?  What model year is your J?

Yes, no special paperwork that I recall. My AP handled the shipping/communicate with them, I did the pulling and installation of the cables. 78J

[jtager]

Thanks again.  I’ll be in touch with McFarlane to see if they can do the same for me.

[Guest]

I don’t know why anyone would want a vernier cable for the throttle?  At most altitudes your not adjusting the throttle, it’s wide open.  Save your money and turn it into more flying.

Clarence

[N201MKTurbo]

I personally hate vernier throttles.

[ArtVandelay]

I personally hate vernier throttles.

Why? Just because you have it, doesn’t mean you can’t use it like non vernier. Best of both worlds.

[N201MKTurbo]

1 hour ago, ArtVandelay said:

Why? Just because you have it, doesn’t mean you can’t use it like non vernier. Best of both worlds.

I noticed yours doesn't have a button. I assume you can move it in and out at any time. That wouldn't be bad.

I have flown planes with a Vernier throttle that had a button. that's the problem.

I normally operate a push pull throttle by grabbing the knob and using one or two fingers on the panel to steady my hand and push the knob in and out. When you have to push the button, you cannot steady the knob with your fingers, which makes it particularly difficult in turbulence.

Besides, I can easily set the throttle to 1/2 in increments without the Vernier, why do you need more precision than that. I find Vernier's indispensable on the mixture, but prop and throttle, not so much. 

[A64Pilot]

Maule has a vernier throttle, the one with a button. I came to love it, if you need throttle all of the sudden simply push with the heel of your hand and that pushes the button in and the throttle advances, butI used my thumb. I really liked the vernier function for fine adjustability and especially because it stays where you left it without having to crank in friction.

‘Why do you think they are on the prop and mixture? Ever flown an aircraft with a mixture without a vernier cable? I have and it’s annoying, tough to make fine adjustments

I found it nice when I was flying down low and didn’t need or want full throttle, I’m not always up at altitude flying long distances, sometimes like this morning it’s a 20 min trip to eat breakfast and then I’m down low and running 22 squared and 7 GPH, no need for fangs out, hair on fire.

They are also nice when letting down, I try to reduce throttle 1 inch a minute in the descent, and the vernier makes that easy, you learn how much turning is 1 inch and don’t even have to look, with a normal throttle your often over adjusting, then adding back.

‘It’s really just a matter of what you get used to, when I first got the Maule, I had planned on getting rid of that silly vernier throttle, but quickly came to like it.

Edited May 2, 2021 by A64Pilot

[ArtVandelay]

I use it on descents as well, continually adjusting to maintain a constant manifold pressure. I certainly could live without it, but it’s only an extra $100 or so...when you’re doing a overhaul , it becomes lost in the bills.

[gsxrpilot]

I love my vernier throttle in my 252. Even though it's a hassle when flying formation. I wouldn't want to be with out it.

The McFarlane vernier throttles are a modified vernier in that they don't have the button. I'd really like one of those and should have done it during the last annual/engine overhaul... but it was just one more thing.

[Mooneymite]

Makes one wonder why big airplanes don't have vernier controls....

I guess those pilots don't have to do anything precisely.  

[carusoam]

+1 for vernier throttle...

Used on every start-up... for repeated throttle position...  two or four half turns... depending on OAT, warm or cold... controlling FF during the operation...

Used on nearly every landing... three half turns... during short final...  enough to give some float.  And remove all float when the runway is made...

 

Kind of like adding an inch of MP without having to look if the adjustment gave what you wanted...  not quite like flying with the trim knob... but close.

 

when pressing the throttle in... the button is there on the end of the knob... it gets pressed as the palm pushes the knob forwards...

 

So... more precision than needed...  but not too much to get in the way...

+1 for owner supplied parts, and macfarlane....

 

Observation....  the best Mooney mechanics in the world don’t use vernier throttle knobs...  

PP thoughts only, further away from being a mechanic than I was yesterday...

Best regards,

-a-

[ArtVandelay]

Makes one wonder why big airplanes don't have vernier controls....<_> I guess those pilots don't have to do anything precisely.  

Do big airplanes have push/pull controls?

[Hank]

3 hours ago, ArtVandelay said:

Do big airplanes have push/pull controls?

Big plane-style controls, in a small plane . . . .

I love my C!

[Mooneymite]

16 minutes ago, Hank said:

Big plane-style controls, in a small plane . . . .

I love my C!

@Hank, is that a B-747 cockpit picture?

Definitely a big airplane quadrant.  

Edited May 2, 2021 by Mooneymite

[Hank]

6 minutes ago, Mooneymite said:

@Hank, is that a B-747 cockpit picture?

Definitely a big airplane quadrant.  

No, it's an Airbus making a hard left turn while taxiing!  

[Mooneymite]

Just now, Hank said:

No, it's an Airbus making a hard left turn while taxiing!  

Probably an A-380, then?

And a precise hard left turn, I bet!  

[Guest]

Three levers, it must be an L1011.

Clarence

[carusoam]

Hmmmmm....

If the fancy levers are so desirable....

When I get my Ultra Acclaim... with the spare door.

is the keyboard going to get in the way?

Dreaming of having first world challenges...   

Best regards,

-a-

[dlthig]

15 hours ago, Mooneymite said:

Makes one wonder why big airplanes don't have vernier controls....

I guess those pilots don't have to do anything precisely.  

Auto throttles are a wonderful thing...

[jtager]

By way of a further update:

Yesterday, I spoke with someone at McFarlane Aviation Products, and I understand that they’re expecting imminent PMA approval for a retrofit vernier cable for the ‘J’, applicable to aircraft serial numbers 24-0378 through 24-3431 (presumably, excluding only the early models with the pedestal / lever arrangement rather than plunger controls).  In fitting the replacement, I gather that the existing microswitch that triggers the low-throttle gear warning mechanism must be transferred to a cutout designed to accommodate it, in the new product.

As Art Vandelay pointed out above, it genuinely seems to be a best-of-both-worlds solution, since there’s no button.  Thanks again for all the feedback, above.  

Edited May 4, 2021 by jtager

[laytonl]

On 5/2/2021 at 6:48 AM, M20Doc said:

I don’t know why anyone would want a vernier cable for the throttle?  At most altitudes your not adjusting the throttle, it’s wide open.  Save your money and turn it into more flying.

Clarence

I was thinking the same thing.  Mine is either wide open or throttled back for landing.  Lee

[birdofjoy]

@jtager did you end up installing MCFarlane's vernier throttles in your J? How do you like it? I want to do that on mine but my serial number is below 24-0378. I'll give them a call to see what the exclusions are about. My aircraft has a push/pull so maybe I could be covered but let's see what they tell me.