About

I'm Dean Scott, a 3D Animator and Graphic Designer and amateur weekend test pilot. This blog documents the construction and fabrication of my custom, NACA 43012 airfoil-based, USC 91 Part 103 ultralight.

In October, 2010 I experienced, let's call it, a very, very hard landing in my "Texas Modified Super Single" Weedhopper Model C ultralight that I had been flying for 9 years. It happened like this:

With its Rotax 503 engine at idle, I was gliding in for a landing at my municipal airport. I began applying up elevator to level out my descent about 50 ft above the ground and 100 ft from the edge of runway 03. As air speed decreased and sink rate increased, I increased up elevator as I neared the ground. At around 2 feet above the runway and with the main axle-mounted control stick pulled almost as far back as it could go, the elevator, at near full up position, began to stall and I knew I was going to hit hard on my main gear, so I jammed the throttle forward to max to quickly get out of the near-stall condition. I would simply land further down the runway.

However, the sudden change of momentum and air pressure on the flight surfaces at full power caused the awkwardly gripped control stick to pull out of my right hand. It flopped back even further, and, due to a badly designed set of control push rod pivot points, locked the elevator in the full up position. Full engine power, plus full up elevator, resulted in a brief, 3 second or so, 40' skyrocket climb, followed by the loss of forward momentum, lift, and the application of gravity.

This is otherwise known as a full-power stall. The nose high attitude quickly reversed into a nose down dive. I frantically tried to unlock the stick and push it forward to recover. However, I wasn't fast enough. THUD! Fortunately, the impact was at a very steep angle, not straight down. A bystander remarked how smart and quick I was to cut the engine to idle before hitting the ground, saving the engine from internal damage to the crank that would happen from such a sudden stop at full power. I did no such thing, so the best I can determine is the engine became starved of fuel at such a nose-high angle.

As you can see, the plane was heavily damaged. Nearly all the fuselage tubes, a pair of wing struts, and the main boom were bent. The seat support tubes, nose strut, and nose wheel fork were broken. The prop protested greatly about becoming a weed whacker, that or the ground didn't move out of the way and told it who was boss. So, overall not a happy landing.

The nose wheel hit first, with the plane at nearly a 45 degree angle. The pilot's seat is mounted to the main landing gear axle and so my tail bone took a sharp, non-fracturing blow when the main wheels were the next item to hit the ground when the plane fell backwards.

Due to the triangular design of the Weedhopper, the front fuselage brace tubes, nose strut, center fuselage brace tubes, and seat tubes absorbed the force of impact such that I only sustained minor bruises and abrasions. On the other hand, my tailbone area protested loudly for a good week after it's beating by the axle.

After unbuckling my four-point harness and climbing out of the crumpled craft, I gathered up the pieces and trailered the battered bird back home, parking her in my garage where I left her, untouched, for 1 year as punishment. Then I decided my car could use the spot during the upcoming winter, so I disassembled "BJ7" into her constituent bundles of tubes, fabric, bolts, and other sundry parts and let her sit for another 2-1/2 years, as I waited for finances to stabilize after the Great Recession and the marriages of the last two of my three daughters.

This blog is to document the reconstruction of my plane, but not back to its original "soft wing" Weedhopper design, but according to my own "hard wing" design, along with other improvements. The video below shows the 3D model I made of this new Weedhopper-based design...

So, Let's Begin!

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May 1, 2014:

I ordered a chromoly main axle from Aircraft Spruce April 29th. It arrived today! Talk about fast UPS standard ground service, sheesh! Maybe living only 2 hrs north of Atlanta helps.

I then ordered all the needed angle, channel, and plate aluminum from Online Metals, April 28th. It arrived today as well, on the same truck. UPS must have had a low volume schedule!

May 6, 2014:

Twelve 1" x .065" x 8' (wing bracing), two 2.5" x .065" x 8' (main boom), and four 1.5" x .065" x 8' (new wing TEs) 6061 T6 tubes from Metal Supermarket that I ordered on April 29th arrived today... a nice birthday "gift."

I salvaged ten 1" tubes from my spare parts collection. Five were old wing struts and two others, a pair of .095" wall front fuselage braces, were the only tubes that survived the nose-dive landing without bending. I also salvaged the 2" schedule 40 pipe inner stiffeners and splicing sleeves from the bent boom.


These blogs will have numerous photos, so to speed up page display and minimize data usage, they will be physically scaled down to low resolution. Simply click on a photo to view it in higher-resolution.