Jigs on the Table

Today I started by gluing the foam to the jigs with small dabs of flox (epoxy mixed with flocked cotton).

You can see the small dabs of flox here.

 While it was curing, I levelled the jig table with a laser level. Then, with strategic hammer taps and chisel nicks, I freed the vertical jigs from their Bondo chains. With the help of my beautiful bride I put the wing assembly on the jig table, bottom side up. After ensuring everything was die straight with the help of my laser level, I used blobs of Bondo to hold the jigs in place. Then I took the top (bottom) of the jigs off.

The wing in all its glory.

 Up next... the spar caps.

Bonding forward core

I bonded the front part of the wing core to the shear web today. Nothing really noteworthy about it, just mix some slurry/micro and go. ...and make extra sure it's all lined up perfectly!

The wing core with various pieces of wood to help weigh it down.

Spar Check

Pulled the aft wing out of its protective box and checked the spar for the correct installed hardpoints. This I did by carefully tapping the shear web with metallic pieces of various sizes, listening for changes in tone and pitch. On this individual Defiant, the plywood hardpoints are done with built-up fiberglass layups.

Doing the "Tap Test" up and down the shear web.

The Defiant Project Day 0

Project Overview

History

This particular Defiant project was started in the late 80's by a well-known and reputable builder (I don't use names unless I have explicit permission). He used a lot of vacuum-bagging and some novel techniques (for back then) to make a very light fuselage. He sold it in 2009 to a couple who worked on it for awhile, but jumped on a flying example, making this project superfluous. I bought it in December of 2012 and it has been sitting in storage for the past 6 months as I dig out from a cross-country move. I anticipate that it will take several more years at the very least to finish it, as my job in the Navy involves lots of long deployments.

What it has

The fuselage is mostly complete, primed, and on the gear. The nosegear is fully functional. Some of the control lines have been run. The center spar has been fabricated and mounted to the fuselage. Most of the interior is finished. A fixed windscreen has been installed, and a large gull-wing door is partially installed. Most of the foam cores for the wing and canard have been cut. The winglets have been fabricated. A generous portion of the metal bit pieces have been created, such as control horns and hardpoints. Vacuum-formed strakes and cowls, in primer, were included. The project came with two LIO-360's, although I regard them as cores at most. A lot of older avionics were included as well, although I will probably sell them and mount a modern EFIS and EMS, as one of the last things to complete.

What it needs

I need to build the wings and canard, including control surfaces, and rig the controls. The strakes need to be mounted. Wings, canard, strakes, and winglets need to be surface finished and primed, and the whole plane painted. Engines need to be rebuilt or reprocured, mounted, and the cowls built around them. The entire instrument panel needs to be planned and installed. 

My boys, Andy and Alex, examine the interior very carefully. Note the protective tarp on the gear; the whole plane is covered as the garage is filled with wing-building implements.

A look under the pilot's side lower instrument panel. From the left, the control stick, rudder pedals (with brake masters installed), pedal adjustment link, nose gear actuator, landing brake actuator, and throttle sextant.

The aft bay (beneath the luggage area). Note aileron cables coiled up, and fuel lines going aft (they currently terminate on the other end of the firewall). At right is one of the header tanks, at present still free floating.

A look at the front side of the instrument panel, behind the front firewall. The pilot's side pedals are at the bottom, the pax pedals at the top. Nosewheel steering and nosegear actuator dominate the lower 1/3 of the photo.

View from port side aft passenger seat. This is going to be a big plane!

Aligning Wing Jigs

Spent a couple of hours sanding the jigs (which had lumps of epoxy from previous jobs), and lining things up horizontally with a laser level. I will still have to level them vertically when I put the cores in.

Rough layout of how the jigs will line up. Of course, they will be standing on end.

Using a laser to align the marks.

What are the Varieze and the Defiant?

In the Beginning

A long time ago, in a galaxy not too far away, Burt Rutan was a young flight test engineer for the Air Force out at Edwards AFB. For reasons that he has never disclosed to me (aside from the fact that he does not know me), Burt moved on. He had been working on a pretty neat canard aircraft called the VariViggen, which he intended as a personal fighter aircraft. It was a nice first design (he had built lots of subscale aircraft but this was his first full-size design). He left his job working for Jim Bede and founded his own company.

The Model 31/33 Varieze

One of the first things he investigated was the feasibility of using composite construction to build a high-aspect-ratio winged canard aircraft. The tiny creature that emerged was christened the Model 31 VariEze (because it was "very easy" to build). He intended it as a one-off research aircraft, but its popular reception at the Oshkosh Airshow encouraged him to sell the plans. This he did, after a redesign to accommodate a bigger engine, the Model 33. The name "Varieze" remained, however, and thousands of plans were sold.

Rutan Model 33 Varieze (from Wikipedia)

The Varieze's forte is speed with efficiency. A completely average example will fly 160 mph at 30 miles per gallon (mpg). A few top-notch examples have flown as fast as 250 mph in the Reno Air Races; others have set world records for distance and efficiency, notching nearly 70 mpg while flying 170 mph. One of the ways it achieves this is with a very small frontal section; the cockpit is pretty tiny!

The Model 40 Defiant

Over the next few years Rutan's inventions became bigger and bolder. In the late 1970's he designed a four/five seat twin-engine push-pull canard aircraft. He held a naming contest for it, and the winning entry was "Defiant," an apt name for an aircraft that defied convention. Supposedly the name "Defiant" actually came from the name for a heating stove. No matter- the aircraft performed magnificently. At one point it was nearly brought to production by Piper; however, Rutan and Piper never saw eye-to-eye and it never came to fruition. Rutan used his Defiant as his personal pickup truck for many years.

The Model 74 Defiant

Burt Rutan fended off requests to publish the plans for his Model 40 Defiant for several years. Eventually, in 1981 he agreed to let Fred Keller, who built an Oshkosh Champion Varieze, construct a Defiant and document the plans and process. The aircraft, the Model 74 Defiant, was built within a year, and the plans were available for sale by mid-1984. Several hundred plans were sold within a few months.

Rutan Model 74 Defiant (from 337skymaster.com)

The Defiant was designed with safety and utility in mind. The aircraft's systems are ingeniously simple, and the excellent performance adds a measure of safety. It is essentially an enlarged Varieze with an extra engine on the front. In contrast to the Varieze's almost complete lack of baggage space, the Defiant has tons of room in addition to the four seats.

Safety

The safety is built in two main ways. First, one of the major contributors to General Aviation accidents is loss of control due to stall and spin; these are most likely to happen at the worst time, when low and slow and approaching the airport on the turn to base or final. The Defiant's canard configuration makes it impossible to stall; specifically, the canard is set up with an incidence such that it stalls before the main wing. With nothing to hold the nose up anymore, the plane bobs down and quickly regains lift without the main wing ever having stalled.

The other big safety contributor is an obvious one: the presence of the second engine. Thanks to the Defiant's low-drag airframe, either engine is able to power the aircraft in a climb by itself. In addition, the inline configuration avoids the extremely dangerous critical engine loss-of-control scenario possible in other twins; briefly, the scenario involves a wing-mounted engine overpowering the tail authority at low speeds and forcing the plane into a wild and violent out-of-control maneuver. The engine-out scenario in the Defiant is ridiculously simple: advance the throttle levers and climb out of danger. No diagnosing which engine, no raising the gear, no accelerating in ground effect. Just climb out and go. I like that.

Epilogue

Burt Rutan's most famous homebuilt, the model 61 Long EZ, was designed after the original prototype Defiant, but before the modified 'production' version; the Long EZ is a modified and enlarged Varieze. Many lessons learned in the original Varieze were applied to the Long EZ and the second Defiant. In 1984, Burt and brother Dick Rutan (and Jeana Yeager) gained considerable fame for the Voyager round-the-world flight. In 1985, after the plans for the Defiant had only been available for a few months, Burt Rutan closed Rutan Aircraft Factory in pursuit of other projects; his company, Scaled Composites, has since built many exotic aircraft that embody his principle of simplicity and performance. The apogee of his career may have been the SpaceShipOne, the first civilian manned space flight in history. Rutan retired in 2011, but is rumored to be working on homebuilt designs in his retirement. 

Varieze serial 339 was completed in 1982, and bought by me in 2006.

Defiant serial 137 was bought in 1984, sold in 2009, and bought by me at the end of 2012.