How your electric flaps work

Never understood why if going electric, they wouldn't do it like a lot of other planes and you dial in a degree and let it go.
The Grumman and also the TB9 I flew, you are counting / staring at the flap on base aiming for half-ish

In the cirrus, just turn it to 50% and get back to your regularly scheduled magenta line
 
cowman said:
So what was the purpose in putting electric flaps on light singles? I assume there had to be some advantage to it besides “oooh it’s electric”
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Some smaller people had difficulty pulling the flap lever. And the manufacturers were also trying to make little airplane cockpits look like airliners. Lots of switches and knobs and dials. It was the pushbutton age. Levers looked like farm tractor technology.
 
cowman said:
So what was the purpose in putting electric flaps on light singles? I assume there had to be some advantage to it besides “oooh it’s electric”
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To make money on selling parts and service?
 
cowman said:
So what was the purpose in putting electric flaps on light singles? I assume there had to be some advantage to it besides “oooh it’s electric”
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Why do all cars have power windows now when a crank handle used to work just fine?
 
Am I the only one that thought this was the beginning of a porno?
 
FormerHangie said:
Compared to the flaps on the AA1s, they are quite effective. I once took off with the flaps down, neither I nor the instructor noticed until we were at cruise and were a few mph slow. For all they did on that airplane, they could have just installed the switch and indicator, and not bothered with the actual flaps.
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True. It's all relative. Compared to the barn doors on 172 they don't make much difference. I think the difference in stall speed is 3 kts.
 
Bill Jennings said:
Why do all cars have power windows now when a crank handle used to work just fine?
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I assume because, especially in a 4 door car it's difficult to roll all the windows up/down from the driver's seat with cranks. It solves a problem. I'm not seeing what problem switching from johnson bar to a more complex electrical control solved.
 
cowman said:
I assume because, especially in a 4 door car it's difficult to roll all the windows up/down from the driver's seat with cranks. It solves a problem. I'm not seeing what problem switching from johnson bar to a more complex electrical control solved.
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It's easy. For a long time the Detroit car manufacturers all competed to bring easier to the driving public. Power steering, power brakes, automatic transmissions, air conditioning, then other power accessories. People like easy. Case in point, most people would love self driving cars.
 
Br-Y-an, I think I know now why your Loran is INOP!! :D

Also, did you notice the steel cable that is moved by the flap assy? You know what it's for? ;)
 
SixPapaCharlie said:
True. But I don't have a set it and forget it switch. I have to count potatoes.
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It's about 3 potatoes per 1/3 deployment of flaps on my Grumman AA5B. They really only create drag and no lift to speak of.
If you are concerned check/clean all connections and look at the brushes on the motor.
 
cowman said:
I assume because, especially in a 4 door car it's difficult to roll all the windows up/down from the driver's seat with cranks. It solves a problem. I'm not seeing what problem switching from johnson bar to a more complex electrical control solved.
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I suppose it could have saved cockpit space. A small electrical switch takes up less space than a Johnson bar. Same goes for many of the current auto-makers resorting to rotary dial-shift selectors in their cars instead of the column- or console-mounted shifter. Fewer moving parts, less space used.
 
Bill Jennings said:
It's easy. For a long time the Detroit car manufacturers all competed to bring easier to the driving public. Power steering, power brakes, automatic transmissions, air conditioning, then other power accessories. People like easy. Case in point, most people would love self driving cars.
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I agree with all of those easy things but the last. I do not want a self driving car.
 
BigBadLou said:
Br-Y-an, I think I know now why your Loran is INOP!! :D

Also, did you notice the steel cable that is moved by the flap assy? You know what it's for? ;)
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I believe that's a switch that turns the motor off since my flap has a full of position where I can set it and forget it. I believe that turns the motor off when the switch is in that full-forward position to keep from burning it up.
 
I "believe" the cable goes to the position indicator next to the trim wheel, but I didn't pay attention to the video.
 
I had a problem in the Cessna where the micro switch casing was cracked, and the flaps would occasionally not retract. It wasn't until the casing crack turned into a full break and a chunk fell out of the plastic casing that the flap retraction failed consistently.
 
cowman said:
I'm not seeing what problem switching from johnson bar to a more complex electrical control solved.
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The Johnson bar occupies space, which could otherwise be used productively, if only for comfort. It's also one less thing to impale you in a crash.
In addition, there may be special circumstances. When Mooney moved from hydraulic flaps to electric flaps, the flap extension speed grew from 100 mph to 120 mph.
 
SixPapaCharlie said:
Never understood why if going electric, they wouldn't do it like a lot of other planes and you dial in a degree and let it go.
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Because limit switches are more likely to require rigging and/or fail than my flap switch and I have many more increments available.

Nauga,
who would rather switch than fight
 
nauga said:
Because limit switches are more likely to require rigging and/or fail than my flap switch and I have many more increments available.

Nauga,
who would rather switch than fight
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Unless you have one of the earlier Cessna electric flaps that had a slip clutch on the jackscrew, you have limit switches on that jackscrew. And some mechanics spritz the jackscrew with LPS, lots of it, and it drips into the switches, gumming them up and interfering with contact conductivity. The right way to lube that screw is with a bit of non-parrafin #10 oil on a clean rag, and you wipe it on. A tiny bit. The slip-clutch screws used moly disulfide grease, and some guys gob that on as if a thick layer is going to lube any better than a film. They get into that habit and they will use the grease on the later jackscrews, really fouling them up because they are recirculating-ball screws. The grease dries out in the ball channels and the balls slip instead of roll and wear out the screw.

Instructions?? Who reads instructions?
 
Clicked on this thread thinking I was going to get to see another Bryan satire.

He let me down!!

Think I'll go light some Cirrus brakes on fire now.
 
Had the electric flaps on a C-150 stick halfway down. Turns out, the outboard wing panels had been replaced sometime in the distant past. Whoever did the repair wasn't very tidy, and a cut rivet left over from the repair work had eventually found it's way into the jackscrew assembly. Luckily no damage. We removed the rivet, and all was well. Scared me though, and was thankful it didn't lock up in the full flap position cause poor little 150's don't like to leave the ground with full flaps in summer heat.
 
Are the two hose clamps installed on the driven section original Grumman parts?

Looks kinda wacky.
 
Capt. Geoffrey Thorpe said:
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This reminded me of a friend's kids recital. She sang that song but pronounced potato and tomato the same way. (rather than po-tate-o, po-tah-toe, to-mate-o, to-mah-toe) Hopefully it's funny in text form. Else: Lets call the whole thing off.

SixPapaCharlie said:
Never understood why if going electric, they wouldn't do it like a lot of other planes and you dial in a degree and let it go.
The Grumman and also the TB9 I flew, you are counting / staring at the flap on base aiming for half-ish

In the cirrus, just turn it to 50% and get back to your regularly scheduled magenta line
Click to expand...

Flap positioning system is an option I've considered for the RV. I currently do the counting method. I count one-thousands. I like to travel light and one-thousands weigh less than potatoes.
 
1RTK1 said:
It's about 3 potatoes per 1/3 deployment of flaps on my Grumman AA5B. They really only create drag and no lift to speak of.
If you are concerned check/clean all connections and look at the brushes on the motor.
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Why did you think potatoes would create lift?
 
Omalley1537 said:
Why did you think potatoes would create lift?
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Enough power/thrust anything will fly!

siXqVfn.jpg
 
3393RP said:
Are the two hose clamps installed on the driven section original Grumman parts?

Looks kinda wacky.
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Looks like they hold the bracket that operates the indicator wire. They do the job and avoid welding to the jackscrew nut. You will find that sort of thing in almost any airplane. Low production numbers mean that specially-made or adapted parts cost much more, so the makers use industrial stuff to do the job. Cessna used an industrial rheostat and panel gauge for flap indication up until '77 or so; more complex and way more expensive to fix now. Those parts are scarce. Hose clamps and Bowden wire will be around for a long time yet for fixing Cirrus' flap indicators.

Cirrus used (at least in the SR20) a length of bungee cord for the rudder-aileron interconnect. I didn't like that. Bungee cord is just latex rubber bands in a fabric casing and it ages horribly. It's the same stuff you strap stuff on your bicycle with.
 
3393RP said:
Are the two hose clamps installed on the driven section original Grumman parts?

Looks kinda wacky.
Click to expand...

Hose clamps... Tubular spar... It makes up for the boxy lower fuselage.
 
First ever composit honeycomb GA plane made I believe
 
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