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Old Oct 21, 2012, 10:47 PM
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Here's the plan for the Maiden flight...

The whole idea behind this plane is to build it for my Dad and ship it to him. At first, I thought I could flight test it here in Florida, but then it won't fit in the original box. I need to leave the Stab and Rudder and nosecone off the airplane to fit in the box. I will ship it to his house in Pennsylvania maybe this Tuesday, then follow myself the weekend of Nov 3rd / 4th for the Maiden flight. The final assembly should only take a few hours.

I have several video cameras including a lightweight wingcam, so we should get some good videos.

Derek
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Old Oct 21, 2012, 11:16 PM
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Quote:
Originally Posted by aspeed View Post
I would just leave the throttle trigger as is, and use the push part of the trigger for shutoff on nitro motors. I know this one is electric though. We used to have the push for brakes, as there was no reverse for nitro motors. Even the indoor electrics, push was brakes. Cars are different than planes though. I'll be waiting for the videos.
I was really not able to leave the throttle trigger alone.

For the stock transmitter used for a car throttle, I'm pretty sure they have the potentiometer set so that full reverse trigger is one endpoint of the channel and full forward trigger is the other endpoint of the channel. If you think of the full range of throw of the trigger / potentiomter as making the channel go from 0 to 100, then full reverse is at 0 and full forward is 100. Neutral (ie, zero car throttle) is around 33 or so. Thus, the speed controller for the car is designed to read 33% as zero throttle. Then anything less than 33% is reverse. Anything more than 33% is forward. (I'm just guessing at 33%, it could be 30% or 35%, it really does not matter, the concept is still the same).

With the stock trigger on the transmitter at the neutral position, when I first tried to arm my ducted fan motor with the airplane ESC, and the trigger at the stock neutral position, the throttle channel was at 33%, thus the ESC saw the throttle at 33% and would not arm the motor. I had to push the trigger to full reverse, to get 0% on the channel, then the motor would arm.

This car transmitter does not have an LCD screen and menu system to be able to see each channel in action like the better airplane transmitters I have. But I know from experience that's what's happening. Each channel has a range from 0% to 100%. Then it's up to whatever electronic device that's plugged into that channel to interpret the setting and do something. For example on the flaps for my 737 airliner, I have a 3 position switch on the Flaps channel. At position 1 the channel reads 0% and the flaps are up. At position 2 it reads 50% and the flaps go to 15 degrees for takeoff and at position 3 the channel reads 100% and the flaps go to 40 degrees for landing.

I took a break today from finishing the handle / transmitter and the leadouts. I will finish up tomorrow.

Derek
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Old Oct 22, 2012, 07:37 PM
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I forgot about the arming thing. We used servos on the cars, and pushing the trigger would push on an actual brake with the nitro ones. The rheostat would give brake, and the ESC would give brake too. I guess the planes are different. The cars are too.
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Old Oct 23, 2012, 12:36 AM
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Cape Coral, FL
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Launch Ramp

This is totally an experiment. It is a launch ramp made of foam rollers. The foam is from a floaty noodle for the swimming pool. It has a 3/4" hole in the middle. The foam is super light and spins freely on 1/2" water pipe. I did a little test by goosing the throttle while still holding onto the top of the fuselage and let the airplane accelerate along the ramp. I only goosed about 1/4 throttle. It will go!! It has better than 1:1 thrust to weight and will literally jump vertically out of my hand. I have good confidence it will launch from this ramp.

Just a few more things and I'll be ready to box it up for shipping to Dad in Pennsylvania. Nothing is glued together yet so the airplane and the ramp can still fit in the box for shipping, that's why I am still using some blue tape here and there, which will go away of course.

Also, I have the ailerons locked down with dummy pushrods. They still have an adjustable clevis, so it's easy to get them aligned neutral. I will wait to see how it flies before making them into flaps and coupled with the elevator. I'm thinking it won't be needed since the tail moment arm is so short.

Derek
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Old Oct 23, 2012, 11:27 PM
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Leadout guides and handle

I am soooo close.

I got the leadout guide done. I wanted to make it as lightweight as possible and still have some adjustability, since I have no idea how much sweep will be needed. It's just a guess at this point. I will glue 2 short pieces of teflon tube into the "chosen" holes for maiden. I made it pseudo adjustable as in, try it and fly it. Then cut the leadouts and re-tie then into another set of holes. The centerline of the leadouts can sweep anywhere from 1/2" to about 3" behind the bellcrank. The bellcrank itself is 3/4" behind the CG. The fat ruler in the photo is 2" wide and the front edge is aligned with the center of the bellcrank. The bellcrank is just sitting on the wing for photo purposes - it resides inside the fuselage as shown before.

The "handle" or whatever it might be called, is done on the transmitter. I did a 25 lb pull test, no problemo - can go lots more. The airplane all up weight is 2 lbs.

Derek
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Old Oct 24, 2012, 11:21 AM
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"I don't fly control line"
Suggest you fly/try a trainer/disposable model First.
Easy as CL may look to the uninitiated, it Does require some practice and skill.
Doing a figure 9 immediately after launch is a v common first time stunt.
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Old Oct 24, 2012, 11:46 AM
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Derek
You really have a nice project going. You build has been very informative and there isalot of useful info
I am thinking of doing the same thing to my handle for lighter planes.
John
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Old Oct 24, 2012, 07:24 PM
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Quote:
Originally Posted by DerekB View Post
I am soooo close.

I got the leadout guide done. I wanted to make it as lightweight as possible and still have some adjustability, since I have no idea how much sweep will be needed. It's just a guess at this point. I will glue 2 short pieces of teflon tube into the "chosen" holes for maiden. I made it pseudo adjustable as in, try it and fly it. Then cut the leadouts and re-tie then into another set of holes. The centerline of the leadouts can sweep anywhere from 1/2" to about 3" behind the bellcrank. The bellcrank itself is 3/4" behind the CG. The fat ruler in the photo is 2" wide and the front edge is aligned with the center of the bellcrank. The bellcrank is just sitting on the wing for photo purposes - it resides inside the fuselage as shown before.

The "handle" or whatever it might be called, is done on the transmitter. I did a 25 lb pull test, no problemo - can go lots more. The airplane all up weight is 2 lbs.

Derek
This is some REAL clever stuff here. I am curious though as to why you didn't just put an adjustable leadout guide on the plane?
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Old Oct 24, 2012, 08:40 PM
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Quote:
Originally Posted by Bare View Post
"I don't fly control line"
Suggest you fly/try a trainer/disposable model First.
Easy as CL may look to the uninitiated, it Does require some practice and skill.
Doing a figure 9 immediately after launch is a v common first time stunt.

Easy? It is quite difficult, on several levels. It is all done "close in" with little (or no) time to react to an adverse situation. Fast reflexes, the ability to instantly make a snap judgement as to what to do and carry it out (usually without thinking about it) and a "stick to it" attitude are among the parameters for success here.
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Old Oct 24, 2012, 08:49 PM
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Cape Coral, FL
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Quote:
Originally Posted by Bare View Post
"I don't fly control line"
Suggest you fly/try a trainer/disposable model First.
Easy as CL may look to the uninitiated, it Does require some practice and skill.
Doing a figure 9 immediately after launch is a v common first time stunt.
I hear what you're saying! Actually I have flown C/L some, but what I mean is I don't have any C/L airplanes myself, only RC, so I don't know all the ins and outs of building a C/L correctly. I will certainly be cautious. When I get up to Pennsylvania, I intend to fly one of my Dad's trainer-like airplanes first to "loosen up". On the BAE Hawk maiden, I intend to set the elevator throw very tame, and double check the balance and such. I've done enough scratch builds and maidens on my R/C airplanes that they fly straight and smooth on maiden with almost no trim adjustments. So, I'm knocking on wood (err, should I say foam ) that I have this Hawk balanced and trimmed good enough that I can just hold her straight and level for the first few battery packs.

We shall see!! It will all be on video .

Quote:
Originally Posted by flyelectcl View Post
Derek
You really have a nice project going. You build has been very informative and there isalot of useful info
I am thinking of doing the same thing to my handle for lighter planes.
John
Thanks for the kind words. I'm excited about seeing this bird fly. My Dad is currently flying 3rd line throttle with the U/Tronics inside the airplane. This transmitter will be new for him too!

Quote:
Originally Posted by JKinTX View Post
This is some REAL clever stuff here. I am curious though as to why you didn't just put an adjustable leadout guide on the plane?
Here's my line of thinking. For an adjustable leadout guide, I had a few considerations. First, I have never seen one, so I don't know what others are doing. Second, anything I thought of myself that's truly adjustable would weigh more than what I came up with. Mine is still "adjustable" in a sense, just not in real time. I want to keep weight to an absolute minimum, so I look at every item. I have learned on my other electric R/C airplanes, if I pay attention to saving weight on every single component, it really adds up. I have other airplanes around this size on RC, and one in particular is 20% heavier than the other (say 2.4 lbs compared to 2.0 lbs). The performance of the 2.0 lb airplane is superior.

So my thought was, every bit of extra weight I add to the leadout guide, I have to compensate with same weight on the outboard wingtip. In the end, once I figure out the best location for the guides, I will probably cut off my guide and just install 2 small tubes.

Anyway, that's my line of thinking. I'm all open for ideas.

Derek
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Old Oct 24, 2012, 09:01 PM
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"Here's my line of thinking. For an adjustable leadout guide, I had a few considerations. First, I have never seen one, so I don't know what others are doing. Second, anything I thought of myself that's truly adjustable would weigh more than what I came up with. Mine is still "adjustable" in a sense, just not in real time. I want to keep weight to an absolute minimum, so I look at every item. I have learned on my other electric R/C airplanes, if I pay attention to saving weight on every single component, it really adds up. I have other airplanes around this size on RC, and one in particular is 20% heavier than the other (say 2.4 lbs compared to 2.0 lbs). The performance of the 2.0 lb airplane is superior.

So my thought was, every bit of extra weight I add to the leadout guide, I have to compensate with same weight on the outboard wingtip. In the end, once I figure out the best location for the guides, I will probably cut off my guide and just install 2 small tubes.

Anyway, that's my line of thinking. I'm all open for ideas".


They are pretty simple- light too. A basic design is a "traveling block" that holds both leadouts and slides back and forth in a slot in the leadout guide. A binding screw is used to fix the block in the desired position. You can buy them ready made from various C/L suppliers, I think Brodak has them in their catalog.

Here's one:

http://brodak.com/control-line-parts...-up-psp-3.html
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Old Oct 24, 2012, 09:05 PM
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Cape Coral, FL
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All boxed up and on it's way to PA!

I did a few final things this morning and packed it all back in the original box, including the new transmitter. That box made it all the way from China to Florida, so just one more leg of the journey to Pennsylvania. I put the launch ramp parts in a 2nd box.

When the airplane arrives in PA, the only thing to do is glue on the 2 stabs, the rudder and the nosecone.

I'm flying up to PA on Wed., Oct 31 and arrive at 10:48 am. There is a good chance, weather permitting, to get a flight in that afternoon. I return home on Monday Nov 5th. So we get about 4-1/2 days and hope the weather is good.

The sad news is I won't have anything new to post until then .

I will be taking a tiny video "wing cam" to mount on the airplane, along with 2 ground video cameras and a helmet video cam . I'll also have my laptop, so the intention is to post videos each night onto Youtube and link them here. That's the plan anyway.

Derek
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Old Oct 24, 2012, 09:33 PM
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Quote:
Originally Posted by JKinTX View Post
"Here's my line of thinking. For an adjustable leadout guide, I had a few considerations. First, I have never seen one, so I don't know what others are doing. Second, anything I thought of myself that's truly adjustable would weigh more than what I came up with. Mine is still "adjustable" in a sense, just not in real time. I want to keep weight to an absolute minimum, so I look at every item. I have learned on my other electric R/C airplanes, if I pay attention to saving weight on every single component, it really adds up. I have other airplanes around this size on RC, and one in particular is 20% heavier than the other (say 2.4 lbs compared to 2.0 lbs). The performance of the 2.0 lb airplane is superior.

So my thought was, every bit of extra weight I add to the leadout guide, I have to compensate with same weight on the outboard wingtip. In the end, once I figure out the best location for the guides, I will probably cut off my guide and just install 2 small tubes.

Anyway, that's my line of thinking. I'm all open for ideas".


They are pretty simple- light too. A basic design is a "traveling block" that holds both leadouts and slides back and forth in a slot in the leadout guide. A binding screw is used to fix the block in the desired position. You can buy them ready made from various C/L suppliers, I think Brodak has them in their catalog.

Here's one:

http://brodak.com/control-line-parts...-up-psp-3.html
Thanks!

I see another one here.

The disadvantage I have is very little C/L flying experience. So I probably don't appreciate how important this device can be. Brodak's description says:

"Adjustable leadouts are an inexpensive way to dramatically improve the performance and handling of your airplane. Nearly every airplane must be trimmed out for flying and to improve performance. In addition, adjustable leadouts enable you to adjust to varying flying conditions, resulting in better overall handling and response. Brodak control-line airplane kits include detailed step-by-step instructions on how to install adjustable leadouts during the construction process."

At least I will be able to do it manually.

Can you describe what I should be looking for during flight to know which way, if any, the guides should be adjusted? How do I know when it's right? What is a good safe "starting point"?

Also, is there a good way to do a pre-flight check for guide location, like hang the airplane from the lines and see how much the nose angles downward. What should I look for?

Also, Brodak says "adjust to varying flying conditions". I just presumed there was one "right" position for a given airplane (other than carrier). I presume they mainly refer to wind (what else varies?). How would you set the guides for calm versus windy? I would guess you move the guides back during higher wind to get more outward pull?

To me, this is the biggest unknown regarding setup.

Derek
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Old Oct 25, 2012, 01:31 PM
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I would like to sugest to install the landing gear. Jets do not have the thrust to get you out of trouble. You need to build up speed to get the bird in the air and that ramp to me is way too short to get the job done.
Put the gear on let it stay on the ground and build up speed and slowly give up elevator and slip it off the ground. Take your time.
And see if you can do it on a paved runway.
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Old Oct 25, 2012, 07:43 PM
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I would like to sugest to install the landing gear. Jets do not have the thrust to get you out of trouble. You need to build up speed to get the bird in the air and that ramp to me is way too short to get the job done.
Put the gear on let it stay on the ground and build up speed and slowly give up elevator and slip it off the ground. Take your time.
And see if you can do it on a paved runway.
Some of the EDF guys cataput the model off the ground like the glider guiders do with a bungee launch.
A very simple adjustable line guide is to make the series of holes as you did, with brass thimbles over the lines a press fit in them. A slot just big enough to allow the lines to pass is cut down the centerline of the series of holes.
To change the line rake, you just press the thimbles out and move the lines to whichever new set of holes you want to use, and press the thimbles back into that set of holes. It is an OLD system.
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