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Lowrider LSA

Low,
The trim tab will just be a small extension of the area of the aileron.
The drooped ailerons are only used during take off, initial climb and possibly landing. You will not be using the autopilot during these phases of flight.

Make sure that you have full down aileron travel when drooped. The drooped position is the new neutral. Full travel must be available from this new neutral. On the 185 when the drooping system was installed the hinge pivot point had to be moved aft a bit so the the full down position wasn't restricted. If the down angle is restricted the other aileron will not go up enough.
 
OK, I suppose my concern was that if the trim tab on the left aileron is in a up or down position what effect will that have since it will provide an imbalance since there will not be a like trim on the right aileron. Maybe the effect will be so small that it won't matter.

I've played with some ideas to allow the tab to "release" from the servo when drooped but as usual, I'm probably overthinking the whole issue.

How do you actuate the droops on your 185? Cable with a handle or motor with a screw to move up or down or what? The movement needs to be exactly the same on each wing.
 
When an aileron trim tab is displaced from neutral both ailerons will find a happy new balanced location. I would ignore the issue.

Since your tabs are small for autopilot purposes only, even one which is stuck "hard over" should be easily overpowered by the pilot. In fact you want to be sure that you can easily overpower an inadvertent "hard over" for safety purposes. You will only want small control surface movements anyway at cruise speeds.

My 185 has a 172 flap motor actuator unit mounted in the left wing. It moves a bellcrank/pulley. The bellcrank portion moves push rods to the aileron special bellcrank which does the drooping by moving the "neutral" point on the bellcrank. The pulley on the bellcrank/pulley is connected by cables to a similar system in the other wing. There are limit switches to control the travel. Also a limit switch which only allows it to operate when the flaps are not up. When the flaps are selected to the up position the switch raises the droop. The operating control is a toggle switch on the control wheel which activates relays to power the 172 flap actuator.
 
I'm in favor of a happy balance!!

I was thinking of using screw drives on each wing or maybe linear actuators with limiter switches so I can flick the switch and the droops will occur together and I can fiddle with the flap handle not having to be concerned with the ailerons. Does that sound... sound?

My thinking is the pitch change will occur together and I will only need to re-trim once until I further expend the flaps. I thought about having a tie between the ailerons and the flaps but that seemed to potentially complicate things if I want flaps and no droop.

I'm guessing there is a speed limit on the droops on your 185. Hard to tell until it flies but I believe flap to 20* would be about the same speed to use for droop.
 
Mine has a single screw drive in one wing tied to the other wing with cables so that there is no possibility of one drooping more than the other. IF one droops more they would still balance, the stick (or yoke) will offset showing the difference. I like the idea of the two ailerons being coupled to droop together. There is no mechanical connection (unlike the Robertson) to the flap handle so that the droop is totally separate from the flaps with the one exception that when the flaps are up the micro switch raises the droop automatically. I do have a switch to bypass this feature. After take off the 185 seems to climb better with the flaps up and the ailerons drooped. The drag from the flaps is gone. Your plane may be different, only testing will tell. The STC says that the droops are not to be used when the flaps are up or during landing. If I was landing with an aft loaded CG, I would use the droop. In the 185 it is usually loaded more forward than aft.

There is no speed limitation for using the droop.

The pitch change is nose down for flaps and droops and would be proportional to the total amount of surface deflection.

You will find that the aileron forces are a bit higher when drooped.
 
I like the happy balance thing where if there is an imbalance it will "self correct" . I know there is a potential for one side to deploy and not the other with both being electrical but then if you can let go of the stick and it will equalize by itself...then what's the risk?

It makes sense that the droops would give a better climb than the flaps. Any idea how much you reduce the stall speed with the droops down and flaps up?
 
The risk is that if the autopilot trim tabs are more powerful than need be. IF one gets stuck at full travel you still need to be able to fly the airplane safely. You may want to flight test for this scenario. Either limit the angle of travel or regulate the size of the tabs.

It's been a while since I tested it. As I recall the stall speed reduction due to the aileron droops is 3-5 mph. That doesn't sound like much until you do some math and find that it is really quite a high percentage of the no droop speed. My 185 is heavy on the amphibs. When low on fuel and solo it will leave the water indicating 37 knots. Without the droops it would be up in the 40s.
 
I was going to start out with a 2" x 8" tab but will be able to easily cut it down or even replace with a larger if needed. That's centered on an 8' aileron.

I've never flown a 185 on amphibs but stock 185 full of stuff on sand sure won't break ground at 37. My plane at 1/3 the weight and bit more than half the horsepower (at least 160) should do well with the droops. My is wing is 160 SF with 8' flaps and 8' ailerons...and of course 1320 gross.

HAPPY 4th to everyone!!!!
 
Got the Astro tester. This RC stuff makes me feel like I'm flying a Microsoft simulator...can't do it.

It says...if I have a BEC circuit...then...
if no BEC circuit then use receiver battery (what voltage is a receiver battery?)
Test your BEC circuit under the kinds of electrical loads expected in flight...what the hell is that?
BEC load is 500 milliamps and cycle time is 20 milliseconds...so what!

Will a 6 volt power supply work instead of a 5 volt?
 
4.8V is std receiver voltage, most servos have speed ratings for both 6 and 4.8 V, you won't hurt anything if you use 6v. Before you use any nominally 6v device, measure it. I'm thinking cheap wall blobs and lantern batteries could be over 7.2V.
 
Thanks Skywalker. I left my multi-meter at my other shop. At least I know what to look for voltage wise.

What BEC seems to mean is a circuit that will operate multiple items (receiver, motor, servo, etc.) from one battery. Am I close and how does that effect my servo testing?
 
Most RC aircraft these days have a huge battery to run the motor, but they are typically 11.4V and higher. To avoid a second 4.8 or 6.0V battery to run the rcv and servos, a BEC(battery eliminator circuit) is used to convert the voltage down. Size (amps) of the BEC increases with the size of the ship, you can buy what you need. So Astro wants you to make sure your BEC is up to your particular job. If you try to grab and limit the motion of the servo arm, does your BEC voltage sag? You'd ask the same question of a battery. So don't worry about BECs, you can find a way to get 4.8 to 6.0v some simpler way. (someone should make a USB to Futaba J connector, USB is a perfect 5.0V, and any laptop has a USB port. Most will give 2A)
 
Now that makes sense!!!

Maybe I can find a USB cable laying around and use that to make up a 5v source. I knew it was a 5v output but it never crossed my little mind to use that as a power source...THANKS!!
 
Correct...USB output on the red and black wires is 5.11volts off my desk top. Now I need to find out where I put the extra power cords. If I remember correctly, they have a red, black and yellow wire. I guess I go to match the red to red and black to black and ignore the yellow? House and auto wiring is a lot simpler.
 
This is probably one of those questions that is obvious to the world but escapes me.

Is there a standard location for nav lights on wing tips? I'm guessing centered on the wing tip vertically and in line with the front wing spar. That looks like a location where trailing or oncoming aircraft could see the lights easily. Is that about right???

Still looking for my power cord to the Astro but it seems to have fallen below the radar at the moment.

Visitors from East and West and maybe one (or the whole family) from our neighbors North of the 49th. Summer is a wonderful time but very very busy!! Also getting ready for a trip to St George, UT in late September. Went to grease the wheel bearings on my ATV trailer and the grease gun is empty...always something...
 
I believe the "rule of thumb" is to install them as far outboard as possible (for best visibility from both front and rear), aligned parallel to the fuselage centerline. Beyond that, you probably want to make sure that they do not glare in the pilot's eyes - sometimes a small "fence" is used on low-wing airplanes for this purpose.
 
Thanks Jim! I'm pretty much in line with your suggestion.

Sky,

Good...that's what I wanted. I couldn't remember where I found that info before. NOW...where's the exception for VFR DAY ONLY planes?

Actually, I believe the location I chose will provide close to the 110* and 70* requirements. I essentially copied the Whelan system in LED's so I think the coverage is adequate...not so sure about the required intensity. How many DAR's will actually test it anyway?
 
Thanks Jim! I'm pretty much in line with your suggestion.

Sky,

Good...that's what I wanted. I couldn't remember where I found that info before. NOW...where's the exception for VFR DAY ONLY planes?

Actually, I believe the location I chose will provide close to the 110* and 70* requirements. I essentially copied the Whelan system in LED's so I think the coverage is adequate...not so sure about the required intensity. How many DAR's will actually test it anyway? I'm also doing wing tip and tail strobe which are bright by my standard anyway.
 
Day VFR, Experimental, 91.205 does not apply. As soon as you go night and or IFR, your operating limitations will require instruments and equipment per 91.205. That said, if you want night on your op limits you need navy lights and anti collision lights that meet the field of view, intensity and color requirements outlined in Part 23, and there is also an advisory circular. While a DAR may not actually check, you will have to supply data to support that your lights meet the requirements.


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That's it!

I have the position lights with anti-collision and I want to put them on the plane in case someone wants to fly at night which of course, I can't do as a Sport Pilot. There is a reasonable chance one of my offspring might want to do night flight.


It looks to me that the lights I have will provide red and green for the full 180* depending upon where I put them on the wing tip. Looks like I need to put them out a couple inches from the edge of the wing tip to get the 110* forward and I think the rear will be OK since they tip tapers to the rear. I guess I can play with the position some and try to measure the angles...it's hard to do on a single wing sitting on a table inside the shop.
 
dga,

The angles, I believe, are fairly easy to measure for the DAR but intensity may not easily convert from "candles" to LED values. There are conversions but my experience with LED's have not lead me to believe they are accurate. My LED's are 3 watt...what ever that convert to in FAR lingo. I will say they are pretty bright by my standard...brighter than a dirt and bug covered Cessna light.
 
Color is also an issue with LEDs. If you buy expensive TSO lights, they have already met the color requirement and intensity requirement. Cheap Chinese LEDs, who knows and it is the applicants responsibility to show compliance. Read AC 20-74 and AC 20-30B. That's the data I would be looking for in order to issue op limits with night. Just an aside, FAA just revised Order 8130.2, now version J to be effective the end of September. A lot of the boiler plate operating limits will change with the new Order.


Sent from my iPhone using Tapatalk
 
Oh yeah...color!

I think the single flashing white light on the vert stab will be the answer. I'll vacuum pack my nav lights and give them to the kids for Christmas.

Maybe one of these clamped to my helmet.
 
These have the wing tip, tail light and strobe all in a wing tip unit. They are working well on my Cub.
http://www.kestrobes.com/AllLED.htm

ledcombo-2.jpg


And this does a good job of controlling flashing LED landing lights for recognition purposes.

http://www.kestrobes.com/beacon.htm#LL1
wig-wag.jpg
 
I have the Kuntzleman strobe unit and the same wig wag to drive the wing tip strobes. I just built the frame to hold more powerful LED's instead of the glass covered unit you have. It's plenty powerful and will provide the nav lights at the angles needed. If I move them out 2" from the wingtip I get the angles just fine. If the DAR doesn't like them, 2 screws and unplug and we go with the tail strobe.
 
OK...everyone probably thinks I went West but actually I have pretty much finished my new shop at ID5 and have a successfully completed plumbing, electrical and structural final inspections. Got a waiver for my driveway since it doesn't meet the fire dept. standards since I still have to build a hanger and house and the existing road will be relocated rather than running thru the "great room" in the house and out the kitchen. FD inspector was very helpful and understanding.

I also am well on the way to completing my conversion of the rear PTO snow blower to fit my front end loader QD plate so I can blow looking forward and not backward anymore. I ordered a 9 tooth sprocket for the engine and a 45 tooth for the blower shaft to get a simple 5:1...2700 at the engine to give standard 540 rpm at the blower. Well. they sent me a 49 tooth so I'm in the process of getting the replacement sprocket in the ordered 45 tooth config. I'm adapting a cheap Harbor Freight 2500lb ATV winch motor to drive the snow chute so I can control it from the tractor cab...winch motor has a remote for in/out of the winch which will convert to right/left for the chute.

Further delayed by my wife's insistance that we take a 2 week vacation. She wouldn't buy the idea that working in the shop is just like a vacation...at least for me. So, we did a 3440 mile trip from North ID, thru MT, WY, UT, AZ, NV and return. Hit Vegas a week after the shooting so we just went to the casino, lost money and left promptly...could have lost money at home and bought airplane stuff or ammo or new tires for my DRZ 400.

Trip was nice and we hit the airshow at Gowan ANG Field in Boise to see the Canadian Snow Birds and the Thunder Birds. T Birds are great and the F-16's are impressive...haven't seen them since they were flying F-4's. The 9 ship formations by the Snow Birds were wonderfully coordinated and I was quite impressed with how they perfectly held wing overlap formations thru loops, rolls and changes of formation...hats off to their team and the maple bacon donuts were great too!

OK...back to Lowrider LSA...this weekend #2 son is coming over to help me hang up the almost completed left wing and I'm starting on the ribs and spars and getting that right wing underway with a goal of pretty much having it done by next Spring...we'll see how that goes...2nd wing goes faster than the first...right?!
 
I was cleaning and deburring the lighting holes in my rear spar and thought maybe someone can benefit from the process I was using to go from rough cut hole to nice smooth edges on the hole.

2017-10-21 10.49.15.jpg

These are the tools I use and I'm sure other folks do it differently. I cut the rough hole in this case with a fly cutter. This time I used my hand drill since my little table top drill press is at my Southern shop. It's much easier to use the drill press if you have one that you can use on an assembly table. Once cut, I use a chain saw file to clean up the really rough spots then put the rotary file on the die grinder to work. It works great but cuts very fast and one needs to go very very slow lest you end up with funny looking holes. I switch to 80 grit flap wheels, then to 120 grit. Together these get the hole pretty smooth and then I switch to the Scotch Bright wheel which brings the hole to a nice smooth polished finish without any scratches. If there are any really small burrs or scratches you can feel them or see them pretty easily and it usually only takes a little application of the Scotch Bright wheel to get rid of them.

That Scotch Bright wheel started out as a 6" wheel and is now about 2.5" so it's done a lot of smoothing over it's life.

Yeah...you need the ear muffs and safety glasses too.

I'm sure there are better ways to get there but I found this is the easiest for me...short of having someone else do it for me. Please feel free to educate me on your methods...I'd love to know a better way since I start on cleaning up ribs tomorrow!!

The cleco's jumped into the picture just as I snapped it...they aren't used in this effort.
 

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