Designed by Scott Binder

I've always liked crop dusters, and having lived in Lowden, WA most of my life,  grew up with them screaming past my bedroom window nearly nightly in the late summers.    Usually Grumman Ag Cats, but later there were also Cessna Agwagons, Snows, and Air Tractors.  My favorite has always been the Air Tractor. 

Lowden was a big Alfalfa seed production area in the 60's through late 90's, and the spray planes were used for pesticide and herbicide application.  I used to watch the planes land in a field adjacent to our family's farm, and also fly from a narrow strip just up the road.

I've always wanted to design and build a sport version of a crop duster - something that resembled one, but built as lightly as possible so that it could be BIG - and a graceful flyer....

My first attempt at designing a model of a spray plane was never built.  The Feather Duster, as I called it, was supposed to be as light as possible, and SLOW.... so I could fly it in a realistic fashion.... It was just too ugly.  Never finished it.

I decided to start over.  By photographing a Snow crop duster just up the road from my house, I was able to get the right "shape", and still add my own touches to the plane... I wasn't interested in building an exact scale replica of a crop duster, I wanted a sport plane that would be super light, and look like the real thing in flight.  In my design program, I literally drew the plans over the photo, coming up with the outline I needed.

To keep it really simple, and use a proven airfoil, I went to some old plans I had for a Kadet Senior.  I used the airfoil to design a new wing that was longer and larger than a Senior wing, and would have a sheeted leading edge.  I scaled it up until I had a 9 foot wingspan.... Just sounded like a good size! :-)  So what I ended up with is essentially a low-wing Kadet Senior, scaled up to a 9 foot wingspan!

Later, I added a longer turbine nose to the existing drawing.... I liked it enough to decide to build the model with that nose.  Originally, I had planned on powering the large model with a gas engine, like a Zenoah G26 or similar.  Eventually, electrics started happening, and I've not flown a "gas" plane for over 2 years - even my larger planes like a H9 Cessna 182 are flown with electric power.  So the decision to go electric was easy.  My E-Flite 160 outrunner flew the 8 foot, 19 lb. Cessna with power to spare, so I figured the Duster could use a 110 outrunner with no trouble.  I eventually chose to use the 160 outrunner, since the price and size difference between it and the 110 are so minimal....

Off and on again over the next several years I tweaked the design until one day I felt I had enough to start building the plane.

In December 06, I started framing.....

The wing and tail were built first - using rib templates I printed out on my sign making equipment.  Using this method, I had accurate, self-adhesive templates to stick directly to the wood.  The ribs were hand cut using a scroll saw.  Wing construction was pretty straight-forward, although I was engineering such things as servo mounts on the fly....  Huge wing when finished!  Very light - about 4 lbs. covered.  My goal is to keep the entire plane under 15 lbs.  That's pretty light for a 9 foot wingspan plane!

The lancair fuselage in the background gives a little perspective to how large this wing is! :-)  'Glassed center section using medium cloth and CA.    Why did I decide on a 1-piece 9 FOOT wing?  Well, I have a runway in my back yard, and rarely fly anywhere else.... so transport is not really a concern..... although if I had it to do over, I'd probably draw it with a two piece wing.

Strangely enough, I decided to build the cowling first.... I don't know why - I just did.  Started framing the fuselage just like building a Senior....

Also, I built the Canopy frame early on.... just wanted to make sure these parts built properly scaled and would be strong enough....

Here you can see the canopy frame and the beginnings of one of the fuselage sides framed up over the printed out full-scale drawings I was able to do on my Roland signmaking equipment.

Several months pass.... Off and on, I work on the Duster... It's now June '07

Chad demonstrates the largeness of the Duster fuselage.....Hard to believe it's gonna be only 15 lbs and fly on a 160 outrunner!  The canopy frame was sealed and painted, and the tail is shown covered in Solartex fabric covering, which is what I decided to cover the majority of the plane with.

My trusty assistant Ralph applies micro-fill after the top of the fuse has been sheeted.....

Another test-fit.... everything's looking good so far, just really BIG!!!  Those are the biggest wheels sullivan makes, and they're still about 1/2" shy of scale!!!  You may or may not have noticed that the canopy frame mysteriously turned primer grey again.... This is because I was not paying attention when installing the landing gear on the fuse - and the whole mess fell off the bench and shattered.... had to completely rebuild the fuse top and canopy..... Oh well!

Although pretty cluttered, this photo shows the beginnings of the spray boom system I'm adding..... Don't plan on spraying anything for real... just want to simulate crop dusting eventually.  I'll get it flying first, then work on the dusting system.  I plan on using a dry system with compressed air..... We'll see.

Another few months go by.....

As of 1/11/08.  Just need to figure out where servos mount and all the internal stuff will go.... keep sanding and finish covering! 

Here's the spray bar booms and a little intake vent for the canopy I carved from balsa...  all primed and painted.

Wing mounted and belly covered.  Balsa belly pan has also been glued to the wing bottom using canpy glue.  Made some neat little turbine exhausts using plastic J bends for plumbing..... painted with brass spraypaint - worked out pretty good!  You can also see the canopy air intake attached to the side of the canopy.

Here's the bottom of the wing, with spray boom arms installed, and belly pan in place.

Starting to turn YELLOW! :-)

Here's the view from the cockpit - a great view of the dustpan, spray can selection, and pile 'o radios.... :-)  Big enough to put my digital camera in the cockpit - can you say "in-flight video"? :-)

This angle shows the cool turbine exhausts, and the canopy doors taped into position to check fit....

Work on installing wing servos continues....

As of 1/21/08, here's how it looks.... Got to finish mounting tail, cover and install ailerons, many many many other finishing touches to go....  A preliminary balance check looks great!  One problem, though - I'm already at 14 lbs. at this stage, so I think my goal of 15 lbs. may have been a bit optimistic..... :-)

Here's my solution to striping..... vinyl!  Just cut and stick.....  Sticks to the Solartex pretty well!

Using masking tape to figure out where the stripes should go, then Ralph cut most of 'em out on the table and we installed them one by one - by hand.

Ralph carefully lines up the stripes.....

There I am, actually working on the plane..... not many photos of me, and that's probably a good thing! :-)  Ralph got a hold of the camera.....

Here's where the advantage of having a sign shop comes in handy..... My printer/cutter prints whatever I've drawn on the computer.... in this case, it's the simulated fiberglass bulk tank and hatch for the top of the fuselage....

All striped up!

As of 1/24//08, here you can see the simulated fiberglass bulk tank and hatch.... canopy door, etc.....  Still gotta do those pesky ailerons.... why do I hate ailerons so much?!?!?!

OK, It's now 2/7/08 - although you can't see it in this photo,  I finally got the ailerons finished and installed.  In fact, the past couple of weeks have been very busy on the Duster.... It's pretty much ready for test flying.... as soon as the batteries come off backorder and show up.  Radio is installed and functioning, all that remains is to install the ESC and batteries.  Here's some more photos......

Here's the struts on the horizontal stab - streamlined K&S aluminum tubing painted Krylon sun yellow.....functional, too! :-)  This shot also shows the really cool old Sullivan tailwheel assembly that my friend Rocky came up with.....  he saw the project, saw the need, and made it his little contribution.  Thanks, Rock!  Did I mention it's functional, too?

Canopy doors glued on, handles made from soft K & S aluminum tubing installed on fuselage.....

Here's another shot of the canopy.... simulated windows on top printed on the printer/cutter.... Ralph's supposed to be working on a seat for me.... but I think he likes the one he's made so much, he's decided to keep it for his own project!!! :-( 

And blammo..... Here's how it looks today.... 2/7/08.   Waiting on some nice weather to go out and take some "real" photos of it in a nice setting.  For now, I'll wait for the backordered batteries and work on making something that resembles plumbing for the spray system....

Ralph prepping the Duster for photos - 2/28/08

Wow - a lot's happened with the Duster Project lately...... For one, it's been sold! :-)  Had an offer that I couldn't refuse - never even got to test fly the plane!  And much to my flying friend's dismay, it's going to a winery to hang from the ceiling... so it'll never fly..... It's OK, though - I've already started on a second one to fly, and I'm building a scale Air Tractor AT402, too!

MORE LATER!

All material © 2008 Scott Binder