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-   -   Rocker switch action and conventions (https://vansairforce.net/community/showthread.php?t=157609)

az_gila 02-09-2018 11:32 PM

Quote:

Originally Posted by vernon smith (Post 1238376)
If I missed this two or three pages ago my apologies, I'm assuming these will meet all the relevant FAA placard requirements, even when not lit?

Good question even though we are Experimental.

This is the relevant text from the new Part 23 certification standards -

? 23.2605 Installation and operation.

(a) Each item of installed equipment related to the flightcrew interface must be labelled, if applicable, as to it identification, function, or operating limitations, or any combination of these factors.

(b) There must be a discernible means of providing system operating parameters required to operate the airplane, including warnings, cautions, and normal indications to the responsible crewmember.

(c) Information concerning an unsafe system operating condition must be provided in a timely manner to the crewmember responsible for taking corrective action. The information must be clear enough to avoid likely crewmember errors.


? 23.2610 Instrument markings, control markings, and placards.

(a) Each airplane must display in a conspicuous manner any placard and instrument marking necessary for operation.

(b) The design must clearly indicate the function of each cockpit control, other than primary flight controls.

(c) The applicant must include instrument marking and placard information in the Airplane Flight Manual.


I would say the above requirements are met with the proposed switch markings, even with no backlighting. Note each switch is either ON or OFF - no three position switches.

Updated version with back-lit indicator "ovals" like the Carling standards for active circuits.


CubedRoot 02-10-2018 12:15 AM

Quote:

Originally Posted by az_gila (Post 1238399)
Good question even though we are Experimental.

This is the relevant text from the new Part 23 certification standards -

? 23.2605 Installation and operation.

(a) Each item of installed equipment related to the flightcrew interface must be labelled, if applicable, as to it identification, function, or operating limitations, or any combination of these factors.

(b) There must be a discernible means of providing system operating parameters required to operate the airplane, including warnings, cautions, and normal indications to the responsible crewmember.

(c) Information concerning an unsafe system operating condition must be provided in a timely manner to the crewmember responsible for taking corrective action. The information must be clear enough to avoid likely crewmember errors.


? 23.2610 Instrument markings, control markings, and placards.

(a) Each airplane must display in a conspicuous manner any placard and instrument marking necessary for operation.

(b) The design must clearly indicate the function of each cockpit control, other than primary flight controls.

(c) The applicant must include instrument marking and placard information in the Airplane Flight Manual.


I would say the above requirements are met with the proposed switch markings, even with no backlighting. Note each switch is either ON or OFF - no three position switches.

Updated version with back-lit indicator "ovals" like the Carling standards for active circuits.


I like this version personally. Easily identifiable, markings re congruent with keeping light leakage to a minimum, and easy to tell when its on or off.

Bill Boyd 02-10-2018 06:53 AM

Re: light leakage
 
Is there anything that can be done to the back side of these switches to mitigate the light leakage? Can you opacify the leaking areas with black paint buildup, for instance?

Snowflake 02-10-2018 09:32 AM

Quote:

Originally Posted by az_gila (Post 1238060)
At a 10,000 hr projected lifetime for the little incandescent lamps I'm fine with non-LED. :)

Note that the 10000hr life is when continuously illuminated. Incandescent bulbs life goes down precipitously with increased on-off cycles. Maybe they've factored some of that in to the life, but it would be hard to know what duty cycle they had in mind for it.

There could be wide variation between a master switch that toggles once a flight, and a fuel pump, smoke system, flap switch, etc. that may actuate multiple times per flight.

Snowflake 02-10-2018 09:37 AM

Quote:

Originally Posted by az_gila (Post 1238128)
Getting closer. If I move the external light switches away, I have a row of 6 on the Aerosport panel pilot side -


This will be personal preference, I understand, but as an industrial designer I would say that a row of "Push On" text kind of looks messy. Simple oval spots as shown in one of the earlier photos could light up to show that the switch has been activated. I don't think anyone will need instructions how to use a rocker switch, so "push on" is also kind of redundant. Just my $0.02...

Oh, and I would move "Master Power" up to be in-line with the text on the other switches. Can leave the icon space blank, but it would look better if the text was all aligned.

az_gila 02-10-2018 10:26 AM

Quote:

Originally Posted by Snowflake (Post 1238475)
This will be personal preference, I understand, but as an industrial designer I would say that a row of "Push On" text kind of looks messy. Simple oval spots as shown in one of the earlier photos could light up to show that the switch has been activated. I don't think anyone will need instructions how to use a rocker switch, so "push on" is also kind of redundant. Just my $0.02...

Oh, and I would move "Master Power" up to be in-line with the text on the other switches. Can leave the icon space blank, but it would look better if the text was all aligned.

I agree it would look better, but my initial question was about which way is ON for a rocker switch - check the earlier posts - and the ON vs OFF labelling came into play. I checked with an AA pilot and he agreed with me on direction issues, but he was also born in Europe. :)

The Master Switch label locations were improved in the latest picture just above.

az_gila 02-10-2018 10:32 AM

Quote:

Originally Posted by Snowflake (Post 1238469)
Note that the 10000hr life is when continuously illuminated. Incandescent bulbs life goes down precipitously with increased on-off cycles. Maybe they've factored some of that in to the life, but it would be hard to know what duty cycle they had in mind for it.

There could be wide variation between a master switch that toggles once a flight, and a fuel pump, smoke system, flap switch, etc. that may actuate multiple times per flight.

This is what Carling says. The bulbs are 80 mA at 12 volts.

Incandescent lamps can accommodate the full range of lens colors, including blue and green. Incandescent lamps offer dispersed beam brightness whose intensity is measured in mean squared candlepower (MSCP). They were once considered the brightest of lamp offerings, however current LED technology can now match incandescent brightness.

Typical incandescent bulb life is 10,000 - 25,000 hours, depending on voltage. Bulb life can also be adversely affected by shock and vibration, voltage swings, and temperature rise. Incandescent lamps can also be susceptible to DC notching, where current flow in one direction can cause a notch to form on the filament. This "cuts" or reduces the cross section of the filament, thus causing it to weaken and eventually cease to function.


The planned ones in the picture are typically used only once or twice per flight. If the lamp life is lowered by a factor of five I'll still be happy. If a boost pump is only used for 10-15 minutes per flight, it will still take a lot of flight hours to reach 500 hrs bulb on time.

Sam Staton 02-11-2018 06:24 AM

Carling switch position
 
All of my switches are Carling, and mine are set up to push the top in to energize. The LEDs in the top part also illuminate then.

az_gila 02-11-2018 08:14 AM

Labels
 
Quote:

Originally Posted by Sam Staton (Post 1238652)
All of my switches are Carling, and mine are set up to push the top in to energize. The LEDs in the top part also illuminate then.

Did you label the ON position in any way?

az_gila 02-11-2018 08:33 AM

One more
 
Quote:

Originally Posted by Snowflake (Post 1238475)
This will be personal preference, I understand, but as an industrial designer I would say that a row of "Push On" text kind of looks messy. Simple oval spots as shown in one of the earlier photos could light up to show that the switch has been activated. I don't think anyone will need instructions how to use a rocker switch, so "push on" is also kind of redundant. Just my $0.02...

Oh, and I would move "Master Power" up to be in-line with the text on the other switches. Can leave the icon space blank, but it would look better if the text was all aligned.

One more variation based on Rob's comments. Add a "label for dummies" as a separate strip above the switches. It does make the switches look neater. The oval icon would illuminate to give a quick visual indication of ON -



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