Cockpit Controls with Unknown Functions

docmirror said:
So, one of the guys wants to go take a leak, and he heads for the exit door and swipes his badge on the reader, but it doesn't release. So, he tries again, then I hear him cuss a bit, and the next thing he does is hit the EPO for the room. Oh spit. Payday friday, and he just took down three running mainframes with one flick of his finger. The company wanted to fire all of us, but I advised them that this would be a mistake as I taught them the first thing once in the comp room was to touch NOTHING without asking. The other guy backed me up, and the button pusher got fired instantly. FIB was pretty unhappy for a while.
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Lol, about 1995, I am working on a wire-guide next to an entrance door into a MRI suite. Someone walks up behind me and startles me causing my big head to hit the emergency power switch for the entire facility :eek:
 
So... That ACR button on the yoke...

I finally got to the point where I was comfortable enough with the plane to be confident in handling a self-induced emergency resulting from pressing the wrong button. I was on an IFR flight. I got an instruction from ATC. I read it back. A minute later, I pushed the button, and then I got the same instruction from ATC... I was about to read it back again, figuring they hadn't heard my read-back, when I heard my own voice reading it back!

So, I guess ACR stands for "Automatic Clearance Recorder" or somesuch. It plays back the last 2 things that were transmitted/received on the radios. Pretty sweet... And completely undocumented!
 
flyingcheesehead said:
So, I guess ACR stands for "Automatic Clearance Recorder" or somesuch. It plays back the last 2 things that were transmitted/received on the radios. Pretty sweet... And completely undocumented!
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What kind of audio panel did that plane have ?
 
flyingcheesehead said:
So... That ACR button on the yoke...

I finally got to the point where I was comfortable enough with the plane to be confident in handling a self-induced emergency resulting from pressing the wrong button. I was on an IFR flight. I got an instruction from ATC. I read it back. A minute later, I pushed the button, and then I got the same instruction from ATC... I was about to read it back again, figuring they hadn't heard my read-back, when I heard my own voice reading it back!

So, I guess ACR stands for "Automatic Clearance Recorder" or somesuch. It plays back the last 2 things that were transmitted/received on the radios. Pretty sweet... And completely undocumented!
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Try pushing it again (multiple times); some clearance recorders will hold several transmissions in their buffers (like the one on the G1000) and each press will play the subsequently previous transmission.
 
weilke said:
What kind of audio panel did that plane have ?
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Just the good ol' King KMA24, seen at the top of the radio stack. The intercom is a separate DRE Communications unit between the annunciator panel and the ELT controls. You can see the ACR button on the yoke next to the Ident button:

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Lots of "stuff" on the yoke too: The red button on the left is autopilot disconnect, the one under it is control wheel steering as previously described in this thread. Speed brakes are on the left side, PTT on the front of the left horn. On the right, you have Ident, ACR, and a switch for SEL or INFO on the Argus 7000 color moving map display (the vertically oriented screen just to the left of the radio stack). Lots of toys in this panel!
 

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Kent:

I know you know I would not lie to you; I was prepared to post the clearance recorder as the answer to your question before I read your confirmation thereof.

If I ever get around to installing my PS engineering audio panel, I will have that as well. If.
 
Sweet! I'd like that next time we need an audio panel.
 
Just below the analog clock and directly above the yoke. Sometimes the white needle will indicate the heading. The red needle can be moved to any position with the small knob in the center.

I've been asking what this gizmo is since I bought her over two years ago. If I ever got an answer, I don't remember it.
 

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flyingcheesehead said:
Just the good ol' King KMA24, seen at the top of the radio stack. The intercom is a separate DRE Communications unit between the annunciator panel and the ELT controls. You can see the ACR button on the yoke next to the Ident button:
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Can't say that I have ever encountered that particular intercom, I suspect the recording capability is in the intercom, if it was part of the KMA24, you would have noticed a scratchy sound ;)

ATC must have wondered why someone read back a 2 year old clearance to them.

You have a lot of buttons on that yoke. Is there a calculator somewhere in there ?
 
weilke said:
Can't say that I have ever encountered that particular intercom, I suspect the recording capability is in the intercom, if it was part of the KMA24, you would have noticed a scratchy sound ;)
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True! :D

The DRE intercom is noticeably better than the old stuff, it's every bit as good as the modern PS Engineering and Garmin units.

You have a lot of buttons on that yoke. Is there a calculator somewhere in there ?
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Probably! :D
 
Some switches on older aircraft you DO need to be careful with.

Some older "vintage" airplanes had flare dispensers. They can usually be spotted as three round holes with covers at the base of the fuselage.

These aren't your run of the mill road flares, but bright, white hot magnesium "star shells" with parachutes that were designed to illuminate un-lit strips (which most were back in the day) for several minutes.

Sooooo....the story goes that a guy takes his "new to him" vintage Bonanza in for it's first annual. He asks the IA about "this dusty switch" in the cockpit. "I was going to play around with it, but never had the time" he says.

The IA says "Well, that's the switch for the flare dispenser, but they've all been deactivated by now".

IA calls a week later to tell the owner that he's all done, and he adds "Ya know what? It turns out the flares were still in the tubes and wired up to that switch..."

Richman
 
flyingcheesehead said:
Nope, that's a CWS (Control Wheel Steering) button - It lets you push it down, fly around by hand for a bit (great for showing pax a better view of something they just saw) and then when you let it go you're back on autopilot with the same modes and such as before.
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Not what CWS does on my 55X. While the CWS is depressed the autopilot is disengaged, but when you release it, it doesn't revert to what it was doing before, it holds the same climb and turn rates that were in effect when you release the button.
 
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flyingron said:
Not what CWS does on my 55X. While the CWS is depressed the autopilot is engaged, but when you release it, it doesn't revert to what it was doing before, it holds the same climb and turn rates that were in effect when you release the button.
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Same on the KFC200.

While it doesn't have constant rate climbs or any of the other fancy modes, with CWS you just take it off 'Alt', set climb power, push the CWS until you have it set to the correct climb attitude and it maintains that attitude. If you left it on whatever lateral guidance (nav or hdg), it will return to that guidance the moment you release CWS. Same with turns.

It's not like the 'resume' button on the cruise control.
 
flyingron said:
Not what CWS does on my 55X. While the CWS is depressed the autopilot is engaged, but when you release it, it doesn't revert to what it was doing before, it holds the same climb and turn rates that were in effect when you release the button.
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It does depend on the mode too. For example, if you're in Nav mode it will return to the correct course, not "hold the same turn rate".
 
flyingcheesehead said:
It does depend on the mode too. For example, if you're in Nav mode it will return to the correct course, not "hold the same turn rate".
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NEGATIVE. The CWS doesn't care which mode you were in (though you need to be in some roll and pitch mode). When released it displays CWS and holds the roll rate and displays and holds the VS.

The only thing that it won't do is exceed 90% (or in some case 75%) of the standard rate turn while in CWS.
 
Richman67 said:
Some older "vintage" airplanes had flare dispensers. They can usually be spotted as three round holes with covers at the base of the fuselage.
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I thought the FAA mandated these be removed. I have a metal patch over the three holes where the flares were. The control panel for the flares was long gone when I got the plane. I actually saw a Navion that still had the control panel (was on the left sidewall of the aircraft) but the flare rack was long gone.
 
flyingron said:
I thought the FAA mandated these be removed. I have a metal patch over the three holes where the flares were. The control panel for the flares was long gone when I got the plane. I actually saw a Navion that still had the control panel (was on the left sidewall of the aircraft) but the flare rack was long gone.
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There is an AD requiring the removal of the flares but that doesn't guarantee compliance.
 
geneseib said:
Just move it and see what it does. ;)
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When we got our new panel I was learning how to use it and my wife asked me to explain what I was doing so she could learn. I told her I was just pushing buttons at random until I got it to do something. She didn't much care for that explanation.
 
I have a carb heat handle in a plane switched to Fuel Injection Turbo. I probably flew 10 hrs before I figured out what it was.

So now I tell people it is the panic handle and if I pull it to start worrying.:)



flyingron said:
I thought the FAA mandated these be removed. I have a metal patch over the three holes where the flares were. The control panel for the flares was long gone when I got the plane. I actually saw a Navion that still had the control panel (was on the left sidewall of the aircraft) but the flare rack was long gone.
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flyingron said:
NEGATIVE. The CWS doesn't care which mode you were in (though you need to be in some roll and pitch mode). When released it displays CWS and holds the roll rate and displays and holds the VS.

The only thing that it won't do is exceed 90% (or in some case 75%) of the standard rate turn while in CWS.
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Huh. I've only used it once in the Mooney, and I was on Nav mode, and I'm pretty sure it went back to Nav mode when I let go...
 
I finally pulled my mystery switch. I was under there already, finding out why the Audio Amp CB stopped the alternator from charging and the Alt Field breaker did not.

It turns out someone ran a 12 ga. power wire from the battery solenoid to a switch mounted to console plastic (with uninsulated terminals) then back to the cargo area to probably power one of those cooler air conditioners. No circuit breaker protection whatsoever.

All the crapola undocumented lighting is going to come out too. I can't imagine why someone would stink up a nice airplane with that stuff.
 
kontiki said:
I finally pulled my mystery switch. I was under there already, finding out why the Audio Amp CB stopped the alternator from charging and the Alt Field breaker did not.

It turns out someone ran a 12 ga. power wire from the battery solenoid to a switch mounted to console plastic (with uninsulated terminals) then back to the cargo area to probably power one of those cooler air conditioners. No circuit breaker protection whatsoever.

All the crapola undocumented lighting is going to come out too. I can't imagine why someone would stink up a nice airplane with that stuff.
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What's amazing is how many times did it pass inspection by an AI over the years, and how many A&Ps saw it, and did nothing about the unprotected circuit?
 
MBDiagMan said:
Just below the analog clock and directly above the yoke. Sometimes the white needle will indicate the heading. The red needle can be moved to any position with the small knob in the center.

I've been asking what this gizmo is since I bought her over two years ago. If I ever got an answer, I don't remember it.
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Radio Compass? If it hasn't been removed it's probly connected to a rather large and heavy remote unit back on the rear radio rack.
 
dmspilot said:
There are some levers on the floor next to the flap handle in various PA28s which are neither labeled nor described in the POH. Somebody opined that they were for sending heat or not to the back seat.
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My Cherokee 140 had a couple of those on each side but they were much farther forward from the flap handle. They ended up being useful for steering the nosewheel while taxiing on the ground.
 
weilke said:
'If it has dust on it or it is painted red, don't touch it'
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This is so true. A lot of our switches are emergency or preflight function switches only. I would say 3/4 of the switches I never touch, thats because the flight engineer touches them :D. There is a lot I don't know about my airplane. Mainly because I am fairly new, but I try to have the flight engineer teach me stuff when we have down time on a trip. If you told me to go back and do some refueling with the boom. I would have no clue how to do it.
 
A friend of mine (who has the plane that was orginally Arthur Godfrey's Navion) has one of those push to test/turn to dim annunciators next to his DG. It lights up when you push it but otherwise the function was a mystery. It turns out the previous owner put it in as a joke, it was his "panic button."
 
Funniest question of the year. Now excuse me while I wipe the coffee off my computer display.
 
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I put some double sided foam tape on the back of a bomb release switch and put it on the panel of a 172M at the flight school.:D

It's amazing how many people admitted to pushing the button and saying "Bombs away!"
 
petrolero said:
Me too. I have no idea if it works or not. I always forget it's there.
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It works and comes in really handy if you have your hands full flying a departure in IMC and approach wants you to ident. Our transponder is one county over on the right hand side of the copilots panel and any head-movement that can be avoided is a good thing.

I believe some citations have to have this button to be eligible for a single pilot waiver, makes sense imho.

I have seen a button on the cyclic of some helicopters that allows you to either flip-flop or cycle through the frequency list on the com radio. Neat feature if you know how to set it up right.

I think we also have a map-light switch, but that one is maybe less important and simply put there to simplify wiring.
 
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Yeah... Like, I have a 430 and a slaved 496, and if asked me how to use them beyond basic functionality... No clue.
 
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