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Lowrider LSA

Low, you need to take a few days off to think about this. You appear to be throwing darts at the board without thinking the process through.

Think about how this plane will be used.

Is it primarily a cruising airplane using just one speed with the same load (CG) on each flight? If so then find the correct location (it will need to be adjustable to do this) then lock the stab in that position and use a trim tab on the elevator or add my grass catcher (little more drag).

Is it going to fly continually at slow speeds, sometimes at higher speeds and sometimes in between with various CG loadings? Efficiently? Comfortably? Maybe on floats in the summer and skis in the winter? If this is the situation then consider a stabilator system like the Comanche, Aztec, Cherokee, Helio or a screw jack controlled stabilizer like a Super Cub, etc. (long list).

Go to Banff and think.
 
Hmmmm.....seems to me I'm over thinking.

I'm using the Riblett wing to get extra speed in cruise and I added flaps for short field off runway ops and the 0-320 to get the power for high DA ops and my project after I get this in the air is building a set of amphibs....I want it to do it ALL, which of course will ALL be a compromise in everything. This is the first major change I've made since I started...all the rest have been evolutionary or based upon suggestions from you folks.

Anyway, off I go to think, think, think and take pictures of the pretty mountains and dodge the tourists...oh yeah, I'll be one of those too!
 
Banff is beautiful and if you haven't been there it's worth the trip IMHO!!

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First shot is Bow River and second shot is Lake Louise.

Too busy to think much but it seems the right answer is the teleflex cable operated trim tab with a lever mounted under the throttle on the left side. We'll see how it works out.
 

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You're right Sky...Winter is on it's way but I'm still wearing shorts and tee shirt back home.

Just wanted to revisit covering tops of flaps and ailerons in 0.016 2024 and the bottom of the flaps with 0.020 rather than using fabric.

Any thoughts?
 
Was the structure designed to be covered with fabric or was the covering designed to be part of the structure? That is the question to ask yourself. Other than that it would be a personal preference. Aluminum covering would increase the torsional stiffness. Is that necessary? The use of aluminum covering would enable the use of fewer or redesigned internal parts, such as the elimination of ribs and trailing edge. Would you be able to use driven rivets or would "pop" rivets be required. "Pop" rivets tend to loosen in high vibration areas such as in the prop blast area. Thin metal skins tend to crack next to rivets in high vibration areas such as in the prop blast area. Personally, "pop" rivets are not allowed on my airplane. I know, there are some which use them extensively.

While I have no observed opinion, I believe that I've heard on these forums that those who have PA-18s with metal ailerons and flaps, prefer the fabric covered ones.
 
Original wing design is pretty much out the window. The LSA wing had no flaps so I've beefed the wings and added them and yes, they need torsional stiffness, especially in the prop blast area which is why I'm leaning to the alum cover. I can buck the rivets except maybe the last 3 on the top skin which will get Cherrys. The flaps are large and the ailerons are 8' long so, yes, I want stiffness there too...which leads me to think alum skin provides a better product than fabric. Also, this an alum wing and not fabric skinned like the SC.
 
Sounds like 2024 is the answer. If you have the last rib flanged outboard and install it last, you may be able to use all hard rivets without the cherries. I don't think that there will be an aerodynamic effect only a personal visual preference.
 
Now that that's settled, is it worthwhile to make covers for the aileron and flap hinge areas to cut the drag, especially the ailerons since the flaps will be up and the openings will be under the wing skin most of the time?
 
That depends on the cruise speed of the plane and whether you want to make airplane parts or go flying. The opening in the ailerons to clear the hinges will not provide noticeable drag. I think that Piper had some little flat plates on the PA-12 ailerons in addition to the strut cuffs in a drag reduction program? Though I believe that their biggest drag reduction for the -12 was the wide fuselage and lower angle of incidence on the wing with the fuselage being the primary reason.
 
A reasonable cruise speed I'm hoping will be around 120 - 125 mph. There are many other areas that will give me drag that I'm probably not going to address but I just thought the holes on the ailerons were an easy way to "slick-up" something without much effort...just a little piece of alum and a few countersunk nut plates.
 
Wiring question: 22 AWG Tefzel is rated at 7 amps in free air and 5 amps enclosed...is running the wire inside the leading edge of a wing thru PVC grommets and holes and a few clamps in the nose ribs considered in free air or enclosed????
 
I stumbled upon some old Cessna clearance lights that take incandescent bulbs and I plan to rewire them and replace the bulbs with LED's so the #22 wire will be fine load wise and won't be anywhere close to 5 amps and I'll run the landing light wires in the same holes and shrink tube them at the grommets in the nose ribs.

Next question...static grounding strap from the fuel tank goes to a CM tab welded to the fuse. Should the grounding for the wing go to the same tab? I'll use the wing spar for ground on the lights.
 
can You please tell us more about the pex tubing? Is Lowes Aviation type pex?
 
Gosh Monte, I'd love to tell you more about PEX but unfortunately all I know for sure is it's used in the hydronic systems in my house and shop. I think it's easier to use since the fittings don't need glue...just push them together. Maybe a Goggle search can give you further info. Sorry I can't be of more help.
 
Ok, question for you float plane drivers...when on floats and moored off shore, I believe it is necessary to have a solid white mooring light illuminated at night the same as you would on a boat and it must be visable 360*. Is it necessary to mount the light on the top of the rudder or can it be in the center o f the fuselage just aft of the skylight where I believe it would be high enough for 360* viewing?

I am putting a flashing strobe for recognition and wanted to do the solid white light in the same dome. Can that work? I have a zenon strobe and a white LED should fit inside the dome.
 
91.209 Aircraft lights.
(3) Anchor an aircraft unless the aircraft--
(i) Has lighted anchor lights; or
(ii) Is in an area where anchor lights are not required on vessels;

It is my understanding that (ii) is referring to "navigable waterways".

Navigable waters, as defined by the US Army Corps of Engineers as codified under 33 CFR 329, are those waters that are subject to the ebb and flow of the tide, and those inland waters that are presently used, or have been used in the past, or may be susceptible for use to transport interstate or foreign commerce while the waterway is in its ordinary condition.

The practice of installing "mooring lights" on amphibious aircraft seems to have stopped during the 1970s. Lake used to install these lights on the top of the fin. The later airplanes did not have "mooring lights". I have never seen these lights installed as part of a Cessna seaplane kit.

I have never moored my seaplane in an area that was not used as a seaplane mooring area, thus lighting was not required. Generally seaplanes are tied to the shore in some manner when away from home.

So, as I see it, the mooring light is optional. Your suggestion should be satisfactory, though I doubt that you will ever use it. If you do use one, separate the electrical source from the battery which starts your engine.
 
Thanks Sky!!

We have a lot of rivers and lakes that fall under COE control which is why I was concerned about compliance. There are many areas with a rocky shore where the plane would be better parked out in the water and not pulled up on the shore but also not too far out in the water.

I agree...a mooring light is probably not worth doing from a practical standpoint but I have seen lights on sailboats moored out in the water which is why I asked. I really don't want a blob on the top of my rudder. I'll proceed with a strobe on the top of the fuselage...thanks again.
 
Interesting discussion at tonight's EAA meeting. I mentioned that I was not using ground wires for wing lights, rather I'd ground to the wing spar instead.

WELL...it brought out a number of forcefully voiced comments saying if you use the wing for a ground your 1st born will get ebola and the plane will go down in flames. After 10 minutes or so I changed the subject but we never got agreement to use the plane structure as a ground...instead there must be a ground wire run to each item powered by electricity.

Any thoughts here????
 
Could anyone tell you why its bad?
Been using the chassis as a ground in automobiles since.... Well since there was automobiles.
Im really not sure what the right answer is, anyone else care to chime in?
 
Did you ask the group how Piper and Cessna wire their airplanes? Did anyone give an example of an airplane which had a separate ground wire? The only time that you would need a ground wire is when the structure is non conductive. Or, if there is a specific electronic device which requires its own separate ground for some reason.
 
The main argument was if a hot wire gets loose or has the conductor exposed it can start a fire. I mentioned the wire should be short protected that would fry the fuse or trip a breaker anyway. I mentioned Cessna and there were several comments about how corrosion at the ground point causes problems and you get better service from a separate ground wire and wire is cheap.

I agree that wire is pretty cheap and may provide better grounding than structure. I have had problems with grounding on trailers and cars/trucks due to corrosion but not that I can recall on a plane.

Any other thoughts or discussion??

I do still have the question above about using a common ground point on the fuselage tubing for electrical and fuel tank static. My guess is it doesn't matter but I thought I should get an "expert" opinion.
 
If a hot wire gets loose then thats potentially gonna happen anyway, because the entire aircraft is grounded. Thats a dumb argument. Piper originally used galvanised tabs for grounding to avoid the dissimilar metal corrosion that your people are talking about. But modern products like di-electric grease, No Alox or even just plain old copper coat (never seize?) do a great job of preventing corrosion due to potential differnce or dissimilar metals.
Automotive stores also sell a "battery paint" the you spray the terminals with after they are connected to the cables, which supposedly stops corrosion and the growth of those big white "sea sponges" on the terminals.
 
KITPLANES magazine had a great article (3 to 5 months ago) on the whys and the wherefors on aircraft electrical grounding, written by a guy whose resume made me a believer. One point that stuck in my mind:pROPER grounding, all ground wires back to a common point, NOT the airframe, was especially beneficial in this day of wazoo glass panels and other electronic goodies. Something about stray electrical currents, interference, and so on. He readily admits the old way works, as we all know, but he made a pretty convincing argument for separate ground wires, or at the very least separate ground busses (that are not grounded) until they then lead directly to that same central stud, firewall mounted, that ground the engine. Even better, leave off any electrical crap you can!

He did mention in passing, then any modern vehicle, uses this central grounding concept, again, because they have so much electronic stuff in them these days.
 
You guys would have fit right in last night.

I'm going to use my wing spar for a grounding point for my wing lights...landing and recognition lights. If I go down in flames you can all say "I told you so".
 
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