109" Hostetler Aeronca Champ build

[BlockerAviation]

A few months ago I embarked on this journey of building the biggest balsa kit I have ever built! This kit is the 109" Hostetler's Aeronca Champ that I got from a fellow club member a while back. The fuselage and tail are all framed up and I just started on the wing last week! I plan on making an update once a week for the thread doesn't get too boring. Anyways I'm really excited to get this thing flying, in fact I've already picked out the color scheme!

Here's the scheme I've chosen!

So today I'll start off by wrapping up the last couple of months of this build and start the weekly posts this weekend. Like I said before, I have the tail and fuse framed up and the wing started. The tail feathers are fairly simple, they build just like most of the ones I've done already. The plans call for using two servos on the elevator but I think that's overkill so I plan on using one servo inside the airplane to save weight and make the over all look of the airplane neater. I'll also be redesigning the rudder servo placement to also make the airframe neater as well. Although the fuselage looks done there is still a lot of work to do. The bottom formers need to be made and installed and the firewall needs to be drilled for my 20cc evolution and installed too. There is also the wing mounting plates that needs to be cut, but I have to finish the wing before I do that.

(Ignore the green on the tail, it was a test piece for another airplane).

Now on to the wing. I had a little trouble with the spar length so I had to do a bit of splicing to get the length I needed. There was also the issue with the servo placement again, namely, I can not stand having servos sticking out of my scale aircraft if I can help it. So I built a tray to mount the servo sideways like how they do in the arfs and other kits. I'm also changing the way the leading edge is done (more on this in next weeks post) and the way the sheer webbing is installed. Over all the way the wing is built is not very clear, so I've kind of had to make it up as I go (keep in mind there is no manual for this airplane) but this has allowed me to make changes to the airplane that really make it my own.

From this,

to this,


Let me wrap this first post up by saying, this airplane is challenging my ability's as a builder, and if you ever get a chance to build a balsa airplane, TAKE IT! You wont regret it! This is going to be my fourth (large) balsa kit I've built and it hasn't gotten old yet seeing an airplane go from a box of sticks to a flying masterpiece.

 

[whackflyer]

Looks super cool! Following for sure!

 

[The Hangar]

A few months ago I embarked on this journey of building the biggest balsa kit I have ever built! This kit is the 109" Hostetler's Aeronca Champ that I got from a fellow club member a while back. The fuselage and tail are all framed up and I just started on the wing last week! I plan on making an update once a week for the thread doesn't get too boring. Anyways I'm really excited to get this thing flying, in fact I've already picked out the color scheme!

Here's the scheme I've chosen! View attachment 192738

So today I'll start off by wrapping up the last couple of months of this build and start the weekly posts this weekend. Like I said before, I have the tail and fuse framed up and the wing started. The tail feathers are fairly simple, they build just like most of the ones I've done already. The plans call for using two servos on the elevator but I think that's overkill so I plan on using one servo inside the airplane to save weight and make the over all look of the airplane neater. I'll also be redesigning the rudder servo placement to also make the airframe neater as well. Although the fuselage looks done there is still a lot of work to do. The bottom formers need to be made and installed and the firewall needs to be drilled for my 20cc evolution and installed too. There is also the wing mounting plates that needs to be cut, but I have to finish the wing before I do that.

(Ignore the green on the tail, it was a test piece for another airplane).
View attachment 192739

Now on to the wing. I had a little trouble with the spar length so I had to do a bit of splicing to get the length I needed. There was also the issue with the servo placement again, namely, I can not stand having servos sticking out of my scale aircraft if I can help it. So I built a tray to mount the servo sideways like how they do in the arfs and other kits. I'm also changing the way the leading edge is done (more on this in next weeks post) and the way the sheer webbing is installed. Over all the way the wing is built is not very clear, so I've kind of had to make it up as I go (keep in mind there is no manual for this airplane) but this has allowed me to make changes to the airplane that really make it my own.
View attachment 192746
From this,
View attachment 192744
to this,
View attachment 192743

Let me wrap this first post up by saying, this airplane is challenging my ability's as a builder, and if you ever get a chance to build a balsa airplane, TAKE IT! You wont regret it! This is going to be my fourth (large) balsa kit I've built and it hasn't gotten old yet seeing an airplane go from a box of sticks to a flying masterpiece.

Awesome project, I’ll be following.

 

[speedbirdted]

This is the kind of build thread I like to see! I have a set of plans for the John Marquette designed 1/3 scale Champ at 141" span in my stash somewhere and it's second or third in line once I get my basement renovated and a new building space set up. I am guessing you are building from the National Balsa short kit? Their stuff is good quality from what I have found. So far your construction looks good!

I especially like Wendell's way of building, all on a square fuselage box with formers and things added onto it. Honestly if I ever get to tackle a Hostetler build it'll either be this one or the Fairchild 24R.

A word of advice on the aileron servos: using one for simplicity and scale reasons might sound appealing but trying to get it to work right without binding all the time is hell to deal with. I built a Great Planes Cub 40 with that system and it got changed to dual servos after one flight because the crappy pushrod system nearly caused a crash. I'm kind of convinced the only reason planes are even designed to have one aileron servo is a remnant from back in the day when servos were so ridiculously expensive that buying any more than was absolutely needed was out of the question.

About ways to deal with separate servos while not having to put up with a servo horn and pushrod sticking out of the bottom of the wing... normally in this situation I would say replicate the pull-pull system that the full scale uses but the Champ does not have the horns for the wires protruding from the wings, so that's out. I would even say using the central servo causes this same problem as the Champ has no aileron control horns whatsoever. The one that comes to mind most prominently is the RDS or Rotary Drive System. Basically, your aileron servos will not have horns but instead a piece of wire extending directly upwards fixed in a collet attached to the servo spline. The wire has a sharp bend in it at the point where the control surface would be hinged. It slots into the control surface. When you rotate the servo, it will deflect the control surface. This is a picture of a RDS drive installed to actuate the rudder of a Hostetler C195:

Here's a good page explaining the concept further.

How will you cover it? I would not bother with plastic films like Monokote. They're hell to get applied well to something this big, sag all the time, disgustingly expensive, plus you have to basically reshrink it every season to get all the wrinkles out. The shiny finish also just kinda looks wrong compared to what a rag and tube airplane is supposed to look like. I would use something like Oratex or Sig Koverall with a sealed and painted finish, so then you can get basically any color you want. Plus, you can use the same paint you used on the fuselage on components like the wheel pants and cowl, components that normally would have to be color-matched to the precolored finish (which is hard to do) and if you get it even a little wrong you'll never unsee it.

 

[BlockerAviation]

This is the kind of build thread I like to see! I have a set of plans for the John Marquette designed 1/3 scale Champ at 141" span in my stash somewhere and it's second or third in line once I get my basement renovated and a new building space set up. I am guessing you are building from the National Balsa short kit? Their stuff is good quality from what I have found. So far your construction looks good!

I especially like Wendell's way of building, all on a square fuselage box with formers and things added onto it. Honestly if I ever get to tackle a Hostetler build it'll either be this one or the Fairchild 24R.

A word of advice on the aileron servos: using one for simplicity and scale reasons might sound appealing but trying to get it to work right without binding all the time is hell to deal with. I built a Great Planes Cub 40 with that system and it got changed to dual servos after one flight because the crappy pushrod system nearly caused a crash. I'm kind of convinced the only reason planes are even designed to have one aileron servo is a remnant from back in the day when servos were so ridiculously expensive that buying any more than was absolutely needed was out of the question.

About ways to deal with separate servos while not having to put up with a servo horn and pushrod sticking out of the bottom of the wing... normally in this situation I would say replicate the pull-pull system that the full scale uses but the Champ does not have the horns for the wires protruding from the wings, so that's out. I would even say using the central servo causes this same problem as the Champ has no aileron control horns whatsoever. The one that comes to mind most prominently is the RDS or Rotary Drive System. Basically, your aileron servos will not have horns but instead a piece of wire extending directly upwards fixed in a collet attached to the servo spline. The wire has a sharp bend in it at the point where the control surface would be hinged. It slots into the control surface. When you rotate the servo, it will deflect the control surface. This is a picture of a RDS drive installed to actuate the rudder of a Hostetler C195:

View attachment 192753

Here's a good page explaining the concept further.

How will you cover it? I would not bother with plastic films like Monokote. They're hell to get applied well to something this big, sag all the time, disgustingly expensive, plus you have to basically reshrink it every season to get all the wrinkles out. The shiny finish also just kinda looks wrong compared to what a rag and tube airplane is supposed to look like. I would use something like Oratex or Sig Koverall with a sealed and painted finish, so then you can get basically any color you want. Plus, you can use the same paint you used on the fuselage on components like the wheel pants and cowl, components that normally would have to be color-matched to the precolored finish (which is hard to do) and if you get it even a little wrong you'll never unsee it.

Thanks! I was definitely planning on using a fabric covering, I don't know if I'll be using pre colored or painting the scheme on yet, but with the gasoline engine, I won't have to use special paint. It'll probably come down to what is available at the time. As for the servos, I'll be using a push rod that splits into a Y for the elevator, a pull pull for the rudder, and in the ailerons I'm using one servo for each aileron but rotating them 90 degrees from what the plan indicates, then I'll put a cover on them and just have the arm sticking out, Witch I'm okay with.

 

[BlockerAviation]

Looks super cool! Following for sure!

Awesome project, I’ll be following.

Thanks guys!

 

[TooJung2Die]

Big build! I'll be watching.

 

[rockyboy]

Woohoo!! It wouldn't be cheap, but consider the Oratex fabric covering from Balsa USA for this - it would give a great finish

 

[BlockerAviation]

Woohoo!! It wouldn't be cheap, but consider the Oratex fabric covering from Balsa USA for this - it would give a great finish

That's the biggest drawback to the Oratex, although I do already have enough red and blue, but I'm also considering using sig Koverall too. Either way It'll have a nice fabric finish!

 

[nhk750]

Im thinking about Sig Koverall for my 1/4 scale cub build so I hope you use it here so I can watch. Nice job on the aileron servos.

 

[BlockerAviation]

On my last post I had just spliced the spars, added them to the wing and sheer webbed the rear. Since then a lot has happened, let me start of with sheer webbing. Since my last post I have added the sheer webbing to front spars, the sheer is made of 1/16 in balsa with the grain oriented up and down as opposed to the 1/8 in side ways balsa the kit called for. After I got finished with the sheer webbing I built the aileron. The aileron was quite simple, the only problem I had was fitting the cap strips to the top of the aileron without having unsightly gaps.

Here's a pic of the aileron before the top cap strips were added.

While I was building the aileron I noticed that because of my servo mod, I would have to move the control horn hard point. The original plans have you glue a balsa block to side of the center aileron rib but Instead I used a 1/4'' ply piece to move the hard point so that it is inline with the servo arm. Then, I sheeted It so it would blend in with the rest of the aileron. This mod will definitely Improve the strength of the control surface.

After I finished the aileron I came to a road block, I didn't have the right balsa to continue on the wing! I was going to start on the leading edge this weekend but I didn't have the 1/4" triangle stock to do It, so I skipped over to the wing tips. The wingtips are made from ten pieces of laser cut balsa or two sets of five. They are made by gluing together the first five pieces, letting them dry, then you build the next five on top to make a really thick piece of balsa. After they are on the wing I'll sand them into shape giving me a nice round edge.

Since, like is said before, I don't have the balsa to continue on the wing, (don't worry I have some on order) I also did some work on the fuselage. The fuselage had a few issues that need to be fixed. These issues had to do with how the stringers met up with the (soon to be sheeted) front of the airplane. Originally the stringers would have not met up flush with the sheeting so I had to add a filet to smoothly bring the stringers up so the met up flush with the sheeting, as seen in the next few pics.

Finally To day I spent a few hours adding in the final sticks to the bottom of the fuse. It took some time to figure out what the plans were saying but after I finally figured it out it went pretty well. Side note, since I wasn't using the provided front sheer webbing, I used it for the bottom to save on materials.

The sticks still have yet to be finish sanded so any bumps you may see will be straightened out then.

To wrap this post up, I'm really happy with how it turning out and am looking forward to its first flight! I'm hopeing to have it done by May but we'll see. I ordered the balsa from Balsa USA on Thursday but I don't Know when It will arrive so the wing will be on hold for a bit. This next week I hope to have the wingtips completed and installed and the spars glued in place. But this all depends on if my balsa arrives. Anyways, Im still stuck between koverall and Oratex for covering so let me know what you think I should do!

-Pilot Blocker-

 

[speedbirdted]

Looking good. I don't know why Hostetler designs tend to have those weird wingtips with the stacked pieces. A simple lamination would more than suffice and would be a lot easier to build and get put together precisely..

 

[Tench745]

Looking good. I don't know why Hostetler designs tend to have those weird wingtips with the stacked pieces. A simple lamination would more than suffice and would be a lot easier to build and get put together precisely..

Because, you can't laser-cut a simple lamination! Seriously though, segmented wing-tips like this are pretty common from the printwood and die-cut kit days. Laminated curves are usually considered an upgrade.

Build looks great! Definitely going to be watching.

 

[BlockerAviation]

Last week the limiting factor for my progress was me waiting for the balsa to move forward with the wing. I finally got it this past Friday and have since been hard at work. To start, I have sheeted the leading edge. This may sound simple but, the plans were very unclear on how to do it and the way it wanted was going to be very difficult to do nicely. Because of this I had to redesign how I was going to build the leading edge, I winded up making a sub leading edge that the leading edge glues onto. After sheeting the leading, edge I cap stripped the top of the ribs, and then moved on to the wing tip.

On the original plans the wing tip is centered on the rib witch means, the top of the wing tapers down and the bottom tapers up to meet in the center. This is not scale at all. On the full scale the top of the wing tip is flat and the bottom comes up to meet it. To fix this I had to do a ton of modifying and fitting to get it to be scale to the full scale but now looking at it finished and ready for shaping, I think it was totally worth it!

There are still a few more things to be done on the first half of the wing though, Like installing and shaping the leading edge, shaping the wingtip, and installing a few more gussets but for now I'm going to get the second half of the wing done and do all the shaping together to try to keep both wings the same. Anyways the next few weeks are going to be a little repetitive but maybe I can include a few more details or even do a build time laps if any of you are interested.

 

[rockyboy]

Making the wing tips slope up from the bottom like that could also have a similar effect to having just a touch of dihedral for added stability too! Nice!

 

[BlockerAviation]

This will be a short post for this week seeing that I already explained the first half's construction. There are some differences that have been causing problems though. On the wing I'm building, the spar is a 1/4 back from where the spar on the is because of the way the wing attaches to the fuse. Because of this, the sheeting that I have is too thin so I'm now weighting for more balsa again. I have also been combating with the poor wood quality in the kit, on one of the sheets, the corners were almost a 1/4in proud of the center! Anyways I'm hopeing that by next week I'll be done with the wings and will be sheeting the fuselage and building the struts but we'll see.

 

[cyclone3350]

I like it. The only real plane I ever got close to buying, was a Champ. This was back quite a few years ago. It wasn't as fancy as the one you have pictured. It had the traditional yellow orange scheme. 6500.00 back then.13500.00 cheaper than a J-3 and just as much fun. The car I was driving finally gave out, so I used the money and bought a VW Golf.

 

[Taildragger]

I like it. The only real plane I ever got close to buying, was a Champ. This was back quite a few years ago. It wasn't as fancy as the one you have pictured. It had the traditional yellow orange scheme. 6500.00 back then.13500.00 cheaper than a J-3 and just as much fun. The car I was driving finally gave out, so I used the money and bought a VW Golf.

ooh now I want to buy one.

 

[cyclone3350]

Nice work so far. Looking forward to when U have it done. My first big build was last year, a Sig 1/4 Clipped Cub. I got it framed up quickly, but my little girl thought it was a cool to put her dolls. Meet Ginger and Cocomelon. Any way still not covered. When I saw SquirrelTail's Cub, it started to motivate me again.

 

[BlockerAviation]

I'm really exited to finally get this thing all framed up. This past week I finished both wing halfs, made the wing spar/braces, and fitted the fire wall. There is still a ton of work to be done though. I still have to sheet the fuselage, cut the wing spar slots, make the center section, make the servo mounts, shape the wingtip, shape the leading edge, and so on and so forth. If I keep building at the rate I'm going I should be able to get it to the field by early to mid summer. Also, from now on my posts should start to get more interesting as I start moving on to the more interesting parts of this build and finish the repetitive parts, so expect some longer and more in-depth posts in the future! I'm also looking into aluminum landing gear instead on the steel wire gear. The steel may look more scale but I'm not sure if Ill be able to bend the wire consistently though but, I'm still on the fence on that. Anyways, let me know what you think of it so far!