Lowrider LSA
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cubdriver2
FRIEND
upstate NY
The British and the Pietenpol guys just use sheet steel and hammer or bend it into a dimensional shape and weld the edges together and weld in bushing. Lite, cheap, simple and strong.
Control horn
Glenn
Control horn
Glenn
skywagon8a
MEMBER
SE Mass MA6
One motor driving both sides. Two will be greater possibility for trouble. You don't want just one drooping. Mine has a 172 flap drive motor mounted in the left wing connected by cables to the right wing.
Is the upper left edge bent as well? Cut a big lightning hole in the middle. Either triangular with big radius corners or a big circle. All of the strength is around the outer edges. The middle of the plate is just dead weight.
Sky,
Bent and welded all the way around. A lightening hole is needed...WILCO.
I was thinking 2, one to drive each side. You're right about 2X the chance of failure but running wire is a lot easier and better I think than cable. How does your cable drive the other side...by wheel, chain and sprocket or what?
Glenn,
That really nice work. Is that yours? Is it a Pietenpol?
Bent and welded all the way around. A lightening hole is needed...WILCO.
I was thinking 2, one to drive each side. You're right about 2X the chance of failure but running wire is a lot easier and better I think than cable. How does your cable drive the other side...by wheel, chain and sprocket or what?
Glenn,
That really nice work. Is that yours? Is it a Pietenpol?
cubdriver2
FRIEND
upstate NY
3 of us met on Monday nights for about 10 years and built 80% of a Pietenpol. Then Ed who's shop we were using bought a Staggerwing project and the Piet went up in the rafters. One member has died and Ed got the Piet down last winter and finshed it by himself. The horn in that picture I posted is not ours but we built everyone on our Piet, landing gear, motor mounts, lift struts......
Ed got it flying this fall and has about 30 hrs on it.
Glenn
Larry G
Registered User
Minocqua WI
Is this what you where thinking of Jim
Attachments
Glenn,
That's gotta be lot of fun to fly! I take the doors off my Challenger in warm weather and it's almost like flying a helicopter with that "open air" flight feeling. Lets see...3 people once a week for ten years got to 80%...how much beer was involved or is this an Irish coffee crowd?
Larry,
Something like that would certainly work. I did some searching around and found there must be a trillion ways to make bell cranks out of every material you can think of. Thanks for the idea!
That's gotta be lot of fun to fly! I take the doors off my Challenger in warm weather and it's almost like flying a helicopter with that "open air" flight feeling. Lets see...3 people once a week for ten years got to 80%...how much beer was involved or is this an Irish coffee crowd?
Larry,
Something like that would certainly work. I did some searching around and found there must be a trillion ways to make bell cranks out of every material you can think of. Thanks for the idea!
Sky,
12-15* and not 30* makes it a lot easier...not sure where I got the 30*...maybe from some 2002 posts from the AK crowd. Full deflection up and down is only 3" on the bell crank so to get 15* down won't take much linear movement at all.
I pulled out the motor that several folks have used for the elevator trim screw and it looks like it would work just fine to get the droop. I believe it uses an 8 or 13 pitch screw so not many revolutions are needed to get the appropriate droop. It is a geared motor so it doesn't pull much power and should be OK with my battery plan since my guess is a couple times per flight would be all that's necessary.
Wish I could find some pictures to show how others have built their system.
12-15* and not 30* makes it a lot easier...not sure where I got the 30*...maybe from some 2002 posts from the AK crowd. Full deflection up and down is only 3" on the bell crank so to get 15* down won't take much linear movement at all.
I pulled out the motor that several folks have used for the elevator trim screw and it looks like it would work just fine to get the droop. I believe it uses an 8 or 13 pitch screw so not many revolutions are needed to get the appropriate droop. It is a geared motor so it doesn't pull much power and should be OK with my battery plan since my guess is a couple times per flight would be all that's necessary.
Wish I could find some pictures to show how others have built their system.
skywagon8a
MEMBER
SE Mass MA6
The 172 flap drive system is connected to a drive wheel which has 2 cables passing through the fuselage to the other wing to another drive wheel. Each drive wheel pushes and pulls push rods which connect to a complicated aileron bellcrank which moves the position of the aileron push rod. You could connect the two wings with one of your push/pull controls.
Your Lowrider Speedbird is one of a kind. You have no idea whether it will need or have the advantage of the installation of any fence or VGs. Leave them off until you determine that you actually NEED them. These items are installed as "fixes" after flight testing is begun. After you get flying, talk to me.
What airplane which has droopers needs the VGs? And where are the VGs located for what purpose? My 185 runs out of rudder control before needing any more mods to the drooping system.
Sky,
I'm opposed to complexity if it's not necessary...less to build, less to fix and less to fail.
I'm still thinking electric motor is the simplest yet reliable way to move the droop. I'll certainly think the push/pull rod out and maybe there is a easy way to apply it to this requirement. Or, how about a power window motor on each side? Thinking...I understand the possibility of one motor failure and the other side retracting on a good motor and asymetrical lift issues. Not sure what the real effect of a 15* droop on one side and not the other...will the other control surfaces overcome the problem? Do you end up with an uncontrollable situation?
When I was doing some research on drooping most of the planes that were involved were Super Cubs with maybe a PA12 or two thrown in there. Some were using VG's and some did not. When a slat was on board they used them just behind there to help hold the air flow down on the ailerons at high AOA. I'm not sure there was popular consent that they were needed/worked however. I'm no where near ready to install the VG's or stall fence so there's time.
I'm opposed to complexity if it's not necessary...less to build, less to fix and less to fail.
I'm still thinking electric motor is the simplest yet reliable way to move the droop. I'll certainly think the push/pull rod out and maybe there is a easy way to apply it to this requirement. Or, how about a power window motor on each side? Thinking...I understand the possibility of one motor failure and the other side retracting on a good motor and asymetrical lift issues. Not sure what the real effect of a 15* droop on one side and not the other...will the other control surfaces overcome the problem? Do you end up with an uncontrollable situation?
When I was doing some research on drooping most of the planes that were involved were Super Cubs with maybe a PA12 or two thrown in there. Some were using VG's and some did not. When a slat was on board they used them just behind there to help hold the air flow down on the ailerons at high AOA. I'm not sure there was popular consent that they were needed/worked however. I'm no where near ready to install the VG's or stall fence so there's time.
skywagon8a
MEMBER
SE Mass MA6
IF, there is an electrical failure so that one aileron is drooped and the other is not, the control stick will be over to one side enough so that the ailerons are equal in deflection. They will both be down an equal amount. You will then be restricted in moving the ailerons in one direction and basically unlimited in the other. In a cross wind landing situation this could be an issue.
Since you are using a push/pull control to move the ailerons, you will need something to fix the end of the housing in order to get the proper motion. IF you mounted this fixed end on a small movable arm (bellcrank) with a separate push/pull control back to the cockpit to manually move it, you would have a simple droop system. Just thinking this through as I type, Hmm rather simple. You could even devise a control which is adjacent to the flap handle which you could grab or not as you wish when the flaps are operated. Sort of like a motorcycle clutch handle mounted on the flap handle with a catch to hold it. Hmmmm this is simpler than I thought.
Since you are using a push/pull control to move the ailerons, you will need something to fix the end of the housing in order to get the proper motion. IF you mounted this fixed end on a small movable arm (bellcrank) with a separate push/pull control back to the cockpit to manually move it, you would have a simple droop system. Just thinking this through as I type, Hmm rather simple. You could even devise a control which is adjacent to the flap handle which you could grab or not as you wish when the flaps are operated. Sort of like a motorcycle clutch handle mounted on the flap handle with a catch to hold it. Hmmmm this is simpler than I thought.
I got the motorcycle clutch part and that had merit too, but I need to get the sliding aileron bell crank out of my mind. I've been thinking the bell crank would slide to the rear from a neutral position to allow the droop to take place. That's why I was thinking a motor operated screw would be the simply way to do it.
So, you're talking about a "second" bell crank in each wing to mount the aileron bell crank on and connect together via a push/pull rod, then have another running to the cabin where it would provide droop to both ailerons at the same time...right?
I haven't set up the aileron to measure 15* and determine how much the bell crank needs to move to the rear to get that much deflection but I'm guessing +/- an inch. Using your idea, I could still use the sliding bell crank operated by a lever in each wing driven by a push pull/rod between the wings to get the same movement and run another rod to the cabin.
The reason I wanted to use a slide fore and aft is to keep the bell crank in straight line with the attachment point on the aileron, although, using a rod end that can swivel on another bell crank could work as well.
Off to do some thinking and measuring.
So, you're talking about a "second" bell crank in each wing to mount the aileron bell crank on and connect together via a push/pull rod, then have another running to the cabin where it would provide droop to both ailerons at the same time...right?
I haven't set up the aileron to measure 15* and determine how much the bell crank needs to move to the rear to get that much deflection but I'm guessing +/- an inch. Using your idea, I could still use the sliding bell crank operated by a lever in each wing driven by a push pull/rod between the wings to get the same movement and run another rod to the cabin.
The reason I wanted to use a slide fore and aft is to keep the bell crank in straight line with the attachment point on the aileron, although, using a rod end that can swivel on another bell crank could work as well.
Off to do some thinking and measuring.
As best I can tell using my little protractor, a level and holding the aileron by myself at the same time it takes 7/8" of movement of the bell crank from neutral to 15* droop...18* being the max down according to the plans. Does anyone see a reason why I can't go to 25* down on the aileron so when it is in 15* droop I would still have 10* of movement to give more aileron authority in the drooped position??
What if...I mounted the primary bell crank on a piece of 3/4" tube (lubed of course) that would slide on the 5/8" supporting tube and milled out a 7/8" long notch in each side of the 3/4" tube and then welded in a pin in the 5/8" that would allow the 3/4" tube to slide fore and aft which would allow 15* droop?
The 3/4" tube would then be controlled by a push/pull rod ending in the cockpit, maybe on the the flap handle or adjacent to the throttle which is on the left side. The other (right) aileron would be slaved to the primary (in this case the left) aileron by another push/pull rod giving it the same droop. Full forward of the bell crank would be neutral aileron and any amount from 0* to 15* droop could be selected and a friction knob at the lever would hold that amount of droop. Or maybe set notches would be better.
While I was figuring the amount of movement it popped into my little mind that I could also add some "up aileron" as well as the droop if it served any purpose.
Thoughts please!!
What if...I mounted the primary bell crank on a piece of 3/4" tube (lubed of course) that would slide on the 5/8" supporting tube and milled out a 7/8" long notch in each side of the 3/4" tube and then welded in a pin in the 5/8" that would allow the 3/4" tube to slide fore and aft which would allow 15* droop?
The 3/4" tube would then be controlled by a push/pull rod ending in the cockpit, maybe on the the flap handle or adjacent to the throttle which is on the left side. The other (right) aileron would be slaved to the primary (in this case the left) aileron by another push/pull rod giving it the same droop. Full forward of the bell crank would be neutral aileron and any amount from 0* to 15* droop could be selected and a friction knob at the lever would hold that amount of droop. Or maybe set notches would be better.
While I was figuring the amount of movement it popped into my little mind that I could also add some "up aileron" as well as the droop if it served any purpose.
Thoughts please!!
skywagon8a
MEMBER
SE Mass MA6
Before I say much more I need to see more. Do you have a picture of how your push rods connect to the ailerons in the wing? How is the end of the push/pull control fixed to the wing? That is where I'm thinking of placing the bellcrank.
I'm off this morning to look at some property but I started a sliding type movement last night so I'll put that together and shoot some pictures for analysis. I upgraded the tube size to 3/4" and 7/8" to make it more resistant to bending since there will be two operations taking place on the support tube. The push/pull will be in line with the tube now and not diagonal to it for the droop actions. Pics to follow.
Still not finished but should give an idea of what I'm doing. 10x32 screw is just in there to show how the pin will hold the sliding tube in proper alignment. Someone misplaced my 0.250" mill so I just cut the notch with a hand grinder. Notch will be re-enforced on sides and ends to only allow the 1.00" movement of the tube to give roughly 15* droop.
#14 shows droop with slide to the rear and #15 is retracted to normal aileron operation.
#14 shows droop with slide to the rear and #15 is retracted to normal aileron operation.
Attachments
skywagon8a
MEMBER
SE Mass MA6
Where does this mechanism mount? In the fuselage or the wing? How is the telescoping tube controlled? Where does that plate attach? Is that push rod connected to the aileron or to the control stick? It looks heavy and complicated.
I thought that you said that the push control was to connect to the aileron directly?
I thought that you said that the push control was to connect to the aileron directly?
It mounts between the front and rear wing spars in line with the aileron control rod which is on the short end of the triangle. It's less than an pound more than the original aileron drive...a 9" piece of 7/8 tube and 18" of 3/4 tube instead of 5/8". The additional push/pull rod will add weight as will the cabin control...the cost of drooping ailerons.
I don't have the whole thing competed which I'll try to get done today. That will make it easier to envision than thru words.
I don't have the whole thing competed which I'll try to get done today. That will make it easier to envision than thru words.
Still not done but here's a couple shots. The first one show the ailerons in droop position and the the other in retracted normal positon.
The rod on the left controls the droop and the one in the center attached to the bell crank does the aileron. I gave the droop a 1.0" travel and as best I can calculate it'll result in about 16* total droop. With the sliding bell crank you get an infinite amount of travel in droop and the other aileron control will be attached at the same spot as the rod in the picture, hopefully giving an equal about of droop to both ailerons. No way to know until I get the other wing done but it looks promising. The other control is a mirror of this one.
The rod on the left controls the droop and the one in the center attached to the bell crank does the aileron. I gave the droop a 1.0" travel and as best I can calculate it'll result in about 16* total droop. With the sliding bell crank you get an infinite amount of travel in droop and the other aileron control will be attached at the same spot as the rod in the picture, hopefully giving an equal about of droop to both ailerons. No way to know until I get the other wing done but it looks promising. The other control is a mirror of this one.
Attachments
skywagon8a
MEMBER
SE Mass MA6
I see where you are going. I think that you can eliminate most all of those parts. I wish that I could draw you a picture. Consider this: Mount a straight movable arm on the rear of the rear spar, parallel to the spar, which is pivoted on one end hinged to the spar. At or near the other end mount the fixed end of your push control with the movable arm connected to the aileron for the aileron control. Then run the droop push control so that the fixed end is mounted forward of the rear spar. The movable end then is connected to the straight arm next to the other cable's fixed end. The distance between where the two are attached to the straight arm will determine how far the droop moves. The droop push control will then move the fixed end of the aileron control the droop amount.
An access hole near the center of the spar web will not likely become a structural problem. If there is a concern then place a reinforcement plate on the web.
Do I make sense?
An access hole near the center of the spar web will not likely become a structural problem. If there is a concern then place a reinforcement plate on the web.
Do I make sense?
Sky,
Of course you make sense! I spent an hour trying to draw that picture in my mind and thus far have failed. I think you are using the rear spar as the anchor point for everything...I just can't picture exactly what you propose.
Mean while, I've finished the parts for both wings and I'm ready to install them in the wing as shown above. Maybe my pea brain is contaminated by the way I designed it but I'm trying to figure out a way to use your ideas and save some weight. These added parts to make the ailerons droop weigh 7 oz per side so I was close with a guess at a pound. I feel comfortable with the extra bracing in the wing and the span between the front and rear wing spars even though it does add weight.
I gotta tell you the way it works now that I have everything together is good and the sliding bell crank works well with the other wing pieces attached. Of course I can't tell how it will work with 60 kts of air moving over the surfaces. Maybe the best answer at least at first is to follow your lead with the placard for "take-off only". I've made so many changes in this craft that it's best to experience them individually when possible.
I discussed this yesterday with a 40K hour ag pilot who said he'd changed so many things in airplanes over the years that he couldn't remember them all but there's nothing wrong with trying new stuff just do it slowly. He said there is a 150 hp C-150 tail dragger with drooping ailerons somewhere but he didn't know how they were done.
I'll think some more about what you described, maybe it'll make more sense in the AM...Thanks for the thoughts!!
Of course you make sense! I spent an hour trying to draw that picture in my mind and thus far have failed. I think you are using the rear spar as the anchor point for everything...I just can't picture exactly what you propose.
Mean while, I've finished the parts for both wings and I'm ready to install them in the wing as shown above. Maybe my pea brain is contaminated by the way I designed it but I'm trying to figure out a way to use your ideas and save some weight. These added parts to make the ailerons droop weigh 7 oz per side so I was close with a guess at a pound. I feel comfortable with the extra bracing in the wing and the span between the front and rear wing spars even though it does add weight.
I gotta tell you the way it works now that I have everything together is good and the sliding bell crank works well with the other wing pieces attached. Of course I can't tell how it will work with 60 kts of air moving over the surfaces. Maybe the best answer at least at first is to follow your lead with the placard for "take-off only". I've made so many changes in this craft that it's best to experience them individually when possible.
I discussed this yesterday with a 40K hour ag pilot who said he'd changed so many things in airplanes over the years that he couldn't remember them all but there's nothing wrong with trying new stuff just do it slowly. He said there is a 150 hp C-150 tail dragger with drooping ailerons somewhere but he didn't know how they were done.
I'll think some more about what you described, maybe it'll make more sense in the AM...Thanks for the thoughts!!
skywagon8a
MEMBER
SE Mass MA6
..............................................................................................................[]..........[]
.......................................................................................Aileron control....[]..........[]
..............................................................................................................[]..........[] Droop control
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XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Spar
.................................[........]...................................................................[]..........[]
.......Fixed to spar pivot [...0xx]xxxxxxxxxxxxxx movable arm xxxxxxxxxxx[x]xxxxx[0]
.................................[........]...................................................................[]
..................................----- .....................................................................[]
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............................................................................/---------------------Aileron ---------------\
Lets see if this helps. Ignore all of the dots they were the only way I could make the drawing work. The Red is the picture.
The housing of the droop control is fixed forward of the spar.
The housing of the aileron control is fixed to the movable arm here x. The amount of travel of this point is the amount of droop. Depending on the amount of travel this x probably should be able to pivot to prevent binding. For you to determine.
The 0 is the pivot bolt for the arm and where the center end of the droop control attaches to the other end.
Place fixed or adjustable stops at the movable end of the arm. One for droop up stop and the other for droop down stop.
The arm can be either aluminum or steel with a bent up or down flange for stiffness to prevent twisting. The highest loads will be between the two push control attach points to the arm. Less towards the pivot end.
You can safely place the aileron travel stops at the stick end of the system ignoring any travel stops at the ailerons. Just be sure to install gust locks on the surfaces if you leave the plane outside where the wind can blow from behind.
Depending on the amount of room available, this whole assembly could be placed forward of the spar with the same results if necessary.
.......................................................................................Aileron control....[]..........[]
..............................................................................................................[]..........[] Droop control
..............................................................................................................[]..........[]
..............................................................................................................[]..........[]
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Spar
.................................[........]...................................................................[]..........[]
.......Fixed to spar pivot [...0xx]xxxxxxxxxxxxxx movable arm xxxxxxxxxxx[x]xxxxx[0]
.................................[........]...................................................................[]
..................................----- .....................................................................[]
...............................................................................................................[]
............................................................................/---------------------Aileron ---------------\
Lets see if this helps. Ignore all of the dots they were the only way I could make the drawing work. The Red is the picture.
The housing of the droop control is fixed forward of the spar.
The housing of the aileron control is fixed to the movable arm here x. The amount of travel of this point is the amount of droop. Depending on the amount of travel this x probably should be able to pivot to prevent binding. For you to determine.
The 0 is the pivot bolt for the arm and where the center end of the droop control attaches to the other end.
Place fixed or adjustable stops at the movable end of the arm. One for droop up stop and the other for droop down stop.
The arm can be either aluminum or steel with a bent up or down flange for stiffness to prevent twisting. The highest loads will be between the two push control attach points to the arm. Less towards the pivot end.
You can safely place the aileron travel stops at the stick end of the system ignoring any travel stops at the ailerons. Just be sure to install gust locks on the surfaces if you leave the plane outside where the wind can blow from behind.
Depending on the amount of room available, this whole assembly could be placed forward of the spar with the same results if necessary.
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OK, the control lines are the push/pull rods. How much stand-off would be needed forward of the rear spar...maybe 4"? How long would the movable arm need to be to get 1" droop movement? The entire mechanism is bolted to the rear spar and the rod from the arm to the aileron (I'll call it the control rod) goes to the attach point on the aileron.
I know the wing skin which will be 0.020 2024 will help stiffen the top and bottom of the rear spar and should reduce (stop) twisting potential but that worries me some. I think there is a lot of pressure/force from air flow on 18" x 8'-0" ailerons and adding in the droop which would probably be for much longer periods and throw in some gusts I end up with a lot of stress on the rear wing spar.
I like the CM tube with attach points on the front and rear wing spars that currently supports the aileron/droop stuff...it's VERY strong. I have a tendency to overbuild but it costs weight.
Let me do some layout on the wing with what I think you have drawn and think about it some. Thanks for the "drawing"...as they say, pictures are worth many words.
I know the wing skin which will be 0.020 2024 will help stiffen the top and bottom of the rear spar and should reduce (stop) twisting potential but that worries me some. I think there is a lot of pressure/force from air flow on 18" x 8'-0" ailerons and adding in the droop which would probably be for much longer periods and throw in some gusts I end up with a lot of stress on the rear wing spar.
I like the CM tube with attach points on the front and rear wing spars that currently supports the aileron/droop stuff...it's VERY strong. I have a tendency to overbuild but it costs weight.
Let me do some layout on the wing with what I think you have drawn and think about it some. Thanks for the "drawing"...as they say, pictures are worth many words.
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Sky,
I took the short piece that bolts to rear spar (without the support that bolts to the front wing spar) and connected both push/pull rods and the aileron control rod. The good news, everything works as it is supposed to, the bad news is the rear spar moves much more than I'm comfortable with. The angle of droop came out at 20* and varied 2* - 3* plus and minus as the aileron was moved up and down with the control rod from what would be the cabin. Using the normal aileron rod and that control which would be the control stick functions and I got just about the same movement of the rear spar as the aileron was raised and lowered.
I put the front support in place and bolted it to the front wing spar and the flexing of the rear spar stopped when the aileron was raised or lowered and drooped. I still have droop at 20* which can be adjusted back to 15* with no problem. Bottom line, it needs the front support in place to relieve the stress from the rear spar.
The pieces I used were probably heavier than the ones that would make up your design but I don't think that difference in weight would make a difference in how much the spar flexed. The wing skin would certainly make a difference. The movement and I guess added leverage of the aileron is what causes the flex in the spar. I think the front spar support is very necessary to stop the flex and while your idea would work it wouldn't be my choice for this application. I also added a "lock out" bolt to stop the droop and can easily be removed to make that feature function. I need to do initial flight testing without the droop active and add it in when I'm comfortable with the handling characteristics of the plane overall.
Thanks for your thoughts and design and maybe it would be applicable to another plane like the cub wing or similar.
I took the short piece that bolts to rear spar (without the support that bolts to the front wing spar) and connected both push/pull rods and the aileron control rod. The good news, everything works as it is supposed to, the bad news is the rear spar moves much more than I'm comfortable with. The angle of droop came out at 20* and varied 2* - 3* plus and minus as the aileron was moved up and down with the control rod from what would be the cabin. Using the normal aileron rod and that control which would be the control stick functions and I got just about the same movement of the rear spar as the aileron was raised and lowered.
I put the front support in place and bolted it to the front wing spar and the flexing of the rear spar stopped when the aileron was raised or lowered and drooped. I still have droop at 20* which can be adjusted back to 15* with no problem. Bottom line, it needs the front support in place to relieve the stress from the rear spar.
The pieces I used were probably heavier than the ones that would make up your design but I don't think that difference in weight would make a difference in how much the spar flexed. The wing skin would certainly make a difference. The movement and I guess added leverage of the aileron is what causes the flex in the spar. I think the front spar support is very necessary to stop the flex and while your idea would work it wouldn't be my choice for this application. I also added a "lock out" bolt to stop the droop and can easily be removed to make that feature function. I need to do initial flight testing without the droop active and add it in when I'm comfortable with the handling characteristics of the plane overall.
Thanks for your thoughts and design and maybe it would be applicable to another plane like the cub wing or similar.
skywagon8a
MEMBER
SE Mass MA6
The torque loads in the spar generated by aileron deflection indicate that you do need a rib or other such device in the location of the aileron push controls which transmits these loads to the front spar. Your sliding tube arrangement could bind when these loads are applied to it. In my opinion you still need a strong rib between the spars in this location to prevent any twisting possibilities.
My droop design is only intended for a system which uses push/pull controls such as yours. It would require further thoughts for another type of system.
My droop design is only intended for a system which uses push/pull controls such as yours. It would require further thoughts for another type of system.
Sky,
The tube that runs between the spars provides solid support to the aileron control and droop movements. There is a rib maybe 6" away but without the skin it does not do a credible job of supporting. The slide moves smoothly now and should work even better once I lube it. It is the load of the aileron in the air flow over and under the wing that worries me since it has leverage on the spars.
The sliding part is stable since the push/pull rod is in line with it's normal movement back and forth for an inch. I made the sliding part longer and larger in tube diameter than it needs to be so it would reduce the possibility of flexing that might cause binding. Dirt, dust and other things that might get in there could cause some issues with the droop system but the actual aileron control on the bell crank should not be a problem and it's also going to be greased thru the zerk. The under side of the wing will have an access panel so it will be easy to access as needed for cleaning, lube or whatever. I made the whole thing so it can be taken apart and cleaned or maintained.
I think it will work and thanks to you and Don for sorta talking me into the mod...can't wait to try it!!
The tube that runs between the spars provides solid support to the aileron control and droop movements. There is a rib maybe 6" away but without the skin it does not do a credible job of supporting. The slide moves smoothly now and should work even better once I lube it. It is the load of the aileron in the air flow over and under the wing that worries me since it has leverage on the spars.
The sliding part is stable since the push/pull rod is in line with it's normal movement back and forth for an inch. I made the sliding part longer and larger in tube diameter than it needs to be so it would reduce the possibility of flexing that might cause binding. Dirt, dust and other things that might get in there could cause some issues with the droop system but the actual aileron control on the bell crank should not be a problem and it's also going to be greased thru the zerk. The under side of the wing will have an access panel so it will be easy to access as needed for cleaning, lube or whatever. I made the whole thing so it can be taken apart and cleaned or maintained.
I think it will work and thanks to you and Don for sorta talking me into the mod...can't wait to try it!!
I'm setting up my trailing edges on the aileron and flap and both are perfectly straight length wise which is pretty easy to set up with an 8' straight edge. The aileron is straight to +/-1/4" in 8' or so vertically and I think that will be taken care of when the fabric goes on if I use the straight edge to keep it as straight as possible during shrinking of the fabric.
The flap on the other hand has about a 3/4" droop on the ends when the center where the control rod activates the flap is held in line with the aileron. I'm thinking that the fabric will also straighten the flap during shrinking as long as I use the straight edge to keep it in the proper alignment.
Is this problem common and will the fabric do the trick to hold the alum frame in line??
The flap on the other hand has about a 3/4" droop on the ends when the center where the control rod activates the flap is held in line with the aileron. I'm thinking that the fabric will also straighten the flap during shrinking as long as I use the straight edge to keep it in the proper alignment.
Is this problem common and will the fabric do the trick to hold the alum frame in line??
patrickh99
Registered User
Just curious: how do you plan to inspect the tele-flex cables for wear?
One of the failure modes is jammed solid; not what I would want on a primary control.
One of the failure modes is jammed solid; not what I would want on a primary control.
marcusofcotton
FRIEND
Cotton, MN
Low, this does not sound good. I've been concerned about flutter with the many points of movement/flex in your aileron control design. Now with this description, I'm getting more worried.
