Mixture Prop Throttle Color & Position

midlifeflyer

midlifeflyer

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Got asked this question and didn't have a good answer. Is the modern right to left red mixture, blue prop, black throttle combination based on regulation or official guidance or unofficial convention or manufacturer consensus (like the GAMA POH)? When did it come about?

Sources for answers are always appreciated.
 
midlifeflyer said:
Got asked this question and didn't have a good answer. Is the modern right to left red mixture, blue prop, black throttle combination based on regulation or official guidance or unofficial convention or manufacturer consensus (like the GAMA POH)? When did it come about?

Sources for answers are always appreciated.
Click to expand...
https://apps.dtic.mil/dtic/tr/fulltext/u2/a052803.pdf

See page 44* and chart at appendix C-11.

*RECOMMENDATION.

It is recommended that consideration be given to regulatory action to standardize the arrangement, location, actuation, and shape of powerplant controls as proposed by the GAMA (appendix C). It is further recommended that the mixture control be color-coded red.​
 
dtuuri said:
https://apps.dtic.mil/dtic/tr/fulltext/u2/a052803.pdf

See page 44* and chart at appendix C-11.

*RECOMMENDATION.

It is recommended that consideration be given to regulatory action to standardize the arrangement, location, actuation, and shape of powerplant controls as proposed by the GAMA (appendix C). It is further recommended that the mixture control be color-coded red.​
Click to expand...

Link doesn’t work for me.
 
Thanks Dave. I think I've seen the study before but was wondering whether it had ever been acted on, either under the FAR or GAMA.
Tspin said:
Link doesn’t work for me.
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Are you sure? It's a pdf. You might have downloaded it rather than opened it in your browser.
 
Multi-engines seem to be the closest to standardization.
Except multi engine amphibs. Some of those have overhead throttles.
Single engine can be all over the place. Especially in Experimental and Light Sport.
 
My Cessna left to right is throttle, prop, mixture but my prop control is black. No matter, I never look at it in flight, I just know it by feel. Carb heat is the one that varies. Reach down to pull carb heat on fonal and pull mixture by accident one time and you pay better attention from then on.

My Cub uses a typical Cub throttle on the side wall, prop on the left panel in line with the throttle, and mixture over on the far right. Very different but no problem.
 
I got my ME in a Barron. Beech went their own way and re-aranged the quadrant. It ruined me for any other twin.
 
Around 1970, motorcycle manufacturers came to a consensus to put the shifter pedal on the left, with a recommended pattern of 1-N-2-3-4-5, going down from neutral into first. I've had many vintage bikes that didn't follow that format (especially Italian beasties.) Standardized controls are a good thing.
 
Kenny Phillips said:
Around 1970, motorcycle manufacturers came to a consensus to put the shifter pedal on the left, with a recommended pattern of 1-N-2-3-4-5, going down from neutral into first. I've had many vintage bikes that didn't follow that format (especially Italian beasties.) Standardized controls are a good thing.
Click to expand...

Even BMW finally capitulted and went with industry standard turn signal controls, I believe starting with the S1000RR. My GS has standard signal controls, my RT before it had the traditional BMW controls.
 
In my plane:

L -> R

Mixture (red) Throttle (black) Prop (black)
 
Mine were in the traditional orientation, but all three were round chrome knobs. I subsequently put the appropriate color and shape knobs on them.

Six pack instruments are another nice compatibility thing.

Another issue is flap vs. landing gear controls. Fortunately the Navion always had the big "wheel" for the gear and the flap shaped thing for flaps. Some Bonanzas had identical piano keys for both.
 
Maxnr said:
I got my ME in a Barron. Beech went their own way and re-aranged the quadrant. It ruined me for any other twin.
Click to expand...

DC-3s I believe had the same arrangement. Note that Beech went to the normal throttle/prop/mixture twin arrangement in 1984 when they got rid of the throwover yoke and went to a more conventional dual yoke setup.

This doesn't help the OP, but it seems that in the late 60s you found most twins standardizing the layout in terms of not only the mixture/prop/throttle layout, but also making sure mixture knobs were red and prop knobs were blue, with the distinctive shape for mixtures vs. props.

Cessna did a couple things unique in the Twin Cessna market. They kept the prop knobs black (I painted mine blue on the 310 and 414). They also put a detent on the props that you had to go past to get to feather. I never liked that at all. Additionally, they put "clickers" on the mixture levers, which made it impossible to easily set your mixture wherever you wanted it. I had thought about removing those clickers from both the 310 and 414 but never did.
 
I've continued to look. Here's what I found in Part 23:

§ 23.671 General.
(a) Each control must operate easily, smoothly, and positively enough to allow proper performance of its functions.
(b) Controls must be arranged and identified to provide for convenience in operation and to prevent the possibility of confusion and subsequent inadvertent operation.

§ 23.1147 Mixture controls.
(a) If there are mixture controls, each engine must have a separate control, and each mixture control must have guards or must be shaped or arranged to prevent confusion by feel with other controls.​

But nothing specifying what they need to be.

Same for GAMA. I found GAMA Publication No. 10, Recommended Practices and Guidelines for Part 23 Cockpit/Flight Deck Design. Echoes Part 23, but still nothing specifying a particular color or order. I have an email to GAMA to see if they can point me in the right direction.

To those who have a different configuration, definitely. With about 30 different singles under my belt, I've seen my share. I flew a Debonair which had a very different order, although there was probably a color-coded upgrade. But you get into the latter year 36s and you find what at least appears to have become standard.
upload_2019-1-28_12-4-26.png upload_2019-1-28_12-6-15.png
 
midlifeflyer said:
Is the modern right to left red mixture, blue prop, black throttle combination based on regulation or official guidance
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Regulation. At least with the old Part 23 for the control position/order (23.777). CAR 3.384 seems to be very general. The only color requirement I read was on "red" for emergency fuel shutoffs which could not be used for any other control color. Hence the red mixture control I would imagine. Where the pics above show black for the throttle I've seen yellow used in older aircraft and in helicopters. However, I don't think it's so much the color but the type of knob as there is a specific knob shape requirement per 23.781. There's also a deviation/exemption for newer aircraft that use a "single control" to control throttle/prop/mixture (AC23-17C). Most of the new Part 23 stuff was moved AC23-17C covering the cockpit controls. The AC uses most of the same paragraph numbers as the old Part 23.

midlifeflyer said:
Sources for answers are always appreciated.
Click to expand...
https://www.law.cornell.edu/cfr/text/14/23.781
https://www.law.cornell.edu/cfr/text/14/23.777
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_23-17C.pdf

upload_2019-1-28_14-6-14.png
 
Thank you @Bell206!

I wouldn't expect CAR 3 to have it.

Old §23.777 takes care of the order, and even includes carb heat/alternate air. Old §23.781 discusses the shape. As you said, nothing about color and your guess about red makes sense.

At the same time, new Part 23 gets rid of all that and the AC23-17C goes back to 2011 before the rewrite to "consensus standards."

So we're still left with the source of the common color scheme and what the future holds - I'm thinking we are going to see consensus standards adopting some of that.
 
I wish my prop knob was blue :( And I wish my mixture knob was a Vernier :( Can those be changed by the A&P?
 
There is something to be said about how manly, and important one feels when man handling a cockpit with 37 leavers, knobs, buttons, switches, clutches, cranks, hasps, palls, and adjusters to all the needles, engines, and dials of a real manly airplane like the Beech 18. Especially when said controls all look and feel the same. [/sarcasam] I'll have you know, I've only enough hours in an 18 to know how much I don't know about flying.

ibe18-16.jpg
 
Kenny Phillips said:
Around 1970, motorcycle manufacturers came to a consensus to put the shifter pedal on the left, with a recommended pattern of 1-N-2-3-4-5, going down from neutral into first. I've had many vintage bikes that didn't follow that format (especially Italian beasties.) Standardized controls are a good thing.
Click to expand...

It was 1976 if I remember right, and it was by federal law. If it wasn’t law I doubt Triumph would have ever switched on the late ‘70s bikes, as they were already on their way out. But I agree, control standardization is a good thing.

As it was, the transmission for the left hand shift triumphs was the same as the right shift ones. They just ran a shaft through the transmission and out the left side. In the process they created another point for them to leak.
 
midlifeflyer said:
new Part 23 gets rid of all that and the AC23-17C
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FYI: AC23-17C along with the ACs listed in the link below are inclusive to the new Part 23 so there not really gone from the certification equation just represented differently.
https://www.faa.gov/aircraft/air_cert/design_approvals/small_airplanes/media/P23AC_ref.pdf
midlifeflyer said:
what the future holds
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Single controls as discussed in the AC and/or electric potentiometers/servos without the benefit of a physical connection to the engine or prop. Just a matter of time.
 
midlifeflyer said:
So we're still left with the source of the common color scheme
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Red = as stated below is the only color indicated in the regs. One of the newer ACs provides examples of "emergency control" which includes a "mixture lever or condition lever." But I forgot to bookmark it.
23.1555(e)(2) Each emergency control must be red and must be marked as to method of operation. No control other than an emergency control, or a control that serves an emergency function in addition to its other functions, shall be this color.

Black throttle and Blue propeller appear to have no regulatory mention except these colors must contrast as stated in 25.777(g): Control knobs must be shaped in accordance with §25.781. In addition, the knobs must be of the same color, and this color must contrast with the color of control knobs for other purposes and the surrounding cockpit.

If I was a betting man, the black/blue color scheme is probably a recommendation adopted by the FAA (maybe around 1985-86) from another standard like SAE or MIL-SPEC. And I think if you could identify the original source for the "Figure 3" below used in the linked EAA article, you might just answer that question.
https://www.eaa.org/en/eaa/aircraft...avionics/cockpit-standardizing-for-homebuilts
33082520830e44de8acf6acc7e261499.ashx
 
Bell206 said:
FYI: AC23-17C along with the ACs listed in the link below are inclusive to the new Part 23 so there not really gone from the certification equation just represented differently.
https://www.faa.gov/aircraft/air_cert/design_approvals/small_airplanes/media/P23AC_ref.pdf
Click to expand...
True, but technically "non-regulatory" in the sense of the standard AC introduction,
1. Purpose. This advisory circular (AC) sets forth an acceptable means, but not the only means, of showing compliance with Title 14 of the Code of Federal Regulations (14 CFR), part 23​
and a more liberal regulatory definition of "acceptable means of compliance" in FAR 23.2010.
dtuuri said:
Looks a lot like the figure I linked to in Post #2. See Appendix C, page 11, from 1976.
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Looks like that to me too, Dave.

At this point, I'm just trying to find documents showing actual adoption of the color scheme by either the FAA or an organization like GAMA.
 
Sinistar said:
I wish my prop knob was blue :( And I wish my mixture knob was a Vernier :( Can those be changed by the A&P?
Click to expand...
Ask your A&P (or one of those here). I've definitely been in aircraft in which the colors (and shapes) were added. And if we're talking about push pull controls rather than levers, I'd be very surprised if to a vernier would be any kind of issue other than paperwork.
 
midlifeflyer said:
I'm just trying to find documents showing actual adoption of the color scheme by either the FAA or an organization like GAMA.
Click to expand...
Why not get it straight from the horses mouth? Drop them a line.
upload_2019-1-30_8-6-59.png
 
Bell206 said:
Why not get it straight from the horses mouth? Drop them a line.
View attachment 71177
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I might ask one of my contacts at the local FSDO once they are back up to speed. I already have an email into GAMA.

But really, if it was ever adopted by the FAA, it should be in at least one of the FAA guidance documents. not in someone's mouth ;). I've searched through my collection which contains most of them.
 
midlifeflyer said:
it should be in at least one of the FAA guidance documents.
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Maybe. But it could also be contained in a separate document listed in the "Related Publications" section of that FAA guidance. You'd be surprised how much industry documentation is used by the feds from external sources like the SAE or RTCA. Or even some guidance found off the beaten path like internal policy memos. Some of my research projects involved 99% industry documentation based on a single FAA guidance link. And I had to buy the industry report to get the info.
 
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Mtns2Skies said:
Yep, what @midlifeflyer said, I'm adding a verneir mixture to my plane at annual, it should be a very simple addition, and not even very pricey.
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If you do this please let me know how it goes. My first preference is for the Vernier mixture. I am guessing a blue prop knob would be much easier. Will it be all be that simple, very curious!
 
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I like the indication of direction on that key as well. The throttle on my boat looks just like the one on my airplane except that it works the opposite way. Pushed in is closed, pulled out is open. I've made a few rapid accellerations until I got the hang of that.
 
My travelair,was backwards,according to the majority,but then again it was a Beechcraft.
 
The very first time I ever got into a Cirrus, before I started my flight training, I looked down and thought, "It's missing a knob!"
 
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