PA-28-161 Piper Warrior II, need help identifying switches

LongRoadBob

LongRoadBob

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Begining student, switching from a pretty new Aquila to a pretty old (but nice!) Piper Cherokee Warrior II.

Had my first flight in it two days ago, and had gone out a few days before to sit in it a little, take some photos to familiarize myself with it.

Problem is that the POH we have for it doesn't go into detail on a few points, AND much worse is that the legends on a few of the switches are worn off (one is covered by what looks like whiteout and I think they had tried to mark it for what it controls). I'm sure they are various light switches, but have gone out on the net finding photographs of the instrument panel, but every single one I found either had the same problem, or the sunlight bleached out the legend, or wasn't detailed enough to see.

On "my" aircraft the switch row has, from left to right

1) a "thumb wheel" switch/potentiometer labeled from the side "Nav Light" "Rad light"
I think turning it downward turns on Nav lights, with a click, then turning it even more is the radio background light, is that correct?

2) master power /alt power. Two red switches in a single switch "cutout"

3) Fuel pump

4) ?? No label

5) ?? No label

6) pitot heat

7) thumbwheel for panel lights.

Could I get confirmation on point 1, and what 4 & 5 switches control?

Thanks for any help!
 
Yes, #1 is right. #4 and #5 are the landing and taxi lights. I couldn't tell you which is which, as I always use both or neither.
 
eman1200 said:
this is from an ARROW, but I recall them being just about identical to the warrior I flew:

View attachment 46371
Click to expand...

Thanks to both of you!

That is what I recalled. It seemed even my CFI wasn't 100% sure but he did point to the ACL and name it, probably the same reason, that he uses both at the same time anyway.

I really appreciate the quick help! Thanks!
 
The thumb wheel operates an on-off switch that provides power in parallel to the Nav lights and to a rheostat. Continuing to turn it varies the brightness of the radio/panel lights using the rheostat for a 71 Cherokee 140.

As to the split switch, you are right that it is Master and the Alternator Field. I believe that it is good practice to first energize the alternator field after the engine is running. Others do not agree. The logic is that cranking pulls the battery voltage down and, if energized, the regulator pumps max current to the alternator field. Then when the engine starts, it is a race between regulator response and alternator output to get things stabilized at 14 volts. I've never had a scope on it but this could result in a voltage spike before that stabilization occurs. Leaving the field shut off until the engine is running and voltage is back to static battery voltage (12 volts) has no negative consequences and provides a smaller transient for the regulator/alternator. Others say that the electronics of the regulator will be so fast that there is no possibility of a voltage overshoot/spike.
 
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Do a search for your year and model POH and you can DL there. I've done it for a few planes.
 
Thanks again, got the exact info I was hoping to get.

I've been through the POH several times, and each time, it's probably been mentioned here before but, I get a laugh out of the description of the "Cigar lighter". That has to be a throwback to the seventies marketing doesn't it? I mean, I grew up in the USA, and in cars it was always called a cigarette lighter, but cigar sounds like some high fallutin' big shot (back then) and maybe more status than a lowly cigarette lighter? It's described as a cigar lighter several places in the POH.
 
Graueradler said:
The thumb wheel operates an on-off switch that provides power in parallel to the Nav lights and to a rheostat. Continuing to turn it varies the brightness of the radio/panel lights using the rheostat for a 71 Cherokee 140.

As to the split switch, you are right that it is Master and the Alternator Field. I believe that it is good practice to first energize the alternator field after the engine is running. Others do not agree. The logic is that cranking pulls the battery voltage down and, if energized, the regulator pumps max current to the alternator field. Then when the engine starts, it is a race between regulator response and alternator output to get things stabilized at 14 volts. I've never had a scope on it but this could result in a voltage spike before that stabilization occurs. Leaving the field shut off until the engine is running and voltage is back to static battery voltage (12 volts) has no negative consequences and provides a smaller transient for the regulator/alternator. Others say that the electronics of the regulator will be so fast that there is no possibility of a voltage overshoot/spike.
Click to expand...
You'll get much more "spike" from just turning the field on.

Cars have the same alternators -- literally in some cases -- and don't have the option of turning the field off. Some of the old ones have regulation "electronics" consisting of a bimetal switch -- they turn the field on and off every few seconds according to heat through a shunt, essentially a real slow current meter. And it operates during engine start.

The alternator output has a rectifier whose job it is to condition the power to a decent DC.
 
MAKG1 said:
Yes, #1 is right. #4 and #5 are the landing and taxi lights. I couldn't tell you which is which, as I always use both or neither.
Click to expand...

I only remember a single light in the nose of the Warrior.
 
HattyDamp said:
Hi...i am a new user here. As per my knowledge it will be good if you will first energize the alternator field after the engine is running. The logic is that cranking pulls the battery voltage down and, if energized, the regulator pumps max current to the alternator field. Then when the engine starts, it is a race between regulator response and alternator output to get things stabilized at 14 volts. I've never had a scope on it but this could result in a voltage spike before that stabilization occurs.
Click to expand...

I have the same concern. I don't know if it is valid or not but energizing the alternator after the engine is running eliminates that possibility with no negative side effects that I can think of. That was my practice.
 
BigBadLou said:
Bob, why didn't you simply turn the switches on to see what lights up? That would have given you an instant answer. :)
Click to expand...

First, I'd have to get out through the right (only) door, comb down, check, get back in, switch...it's a whole big thing. Then too, at this stage, I wouldn't be sure which is called which, and lastly I still have to memorize it so I wrote it up so I can recall...its just better.
 
LongRoadBob said:
First, I'd have to get out through the right (only) door, comb down, check, get back in, switch...it's a whole big thing. Then too, at this stage, I wouldn't be sure which is called which, and lastly I still have to memorize it so I wrote it up so I can recall...its just better.
Click to expand...
You need to do that in preflight anyway.

No need to get in. You can reach the switch bank kneeling on the right wing. And the flaps, too.
 
From left to right:
Nav lights - pinwheel
Battery (usually red)
Fuel pump
Landing light
Beacon (that thing on the top of the tail)
Pitot Heat (if you have it)
Panel lights (and overhead light, too) - pinwheel
 
Don't forget you can check lights in a dark hangar without ever leaving the cockpit. :)
You also have the same luxury at night on tie-downs.
 
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