Working on the Rear Spar

Starting the rear spar. Not real difficult so far, just a lot of deburring. Deburring keeps scratches from growing into cracks due to vibration. It is convenient having two of the standard sized (5'x2') EAA 1000 work tables on wheels and bolted end-to-end as the spars are about 9' long. I built the standard tables but customized them with locking wheels, an inset back-rivet plate, two drawers, an electric plug strip, and long bolts that allow them to be bolted side-by-side or end-to-end.

Finished with Tie Downs

Here are the finished tie downs. Picture the threaded ring hanging down under the wing. That's where the rope or chain will attach. I had to tap (thread) the inside of the block where the ring screws. Austin and I have a lot of experience using the tap and dies from working on the Dart. It was much easier working with aluminum which gives me pause about the strength but there are over 6500 RV's flying and I've never heard about people having problems.

Speaking of RV's flying, I read yesterday that an organization that covers certified aircraft reported that 965 CERTIFIED piston aircraft were sold in 2009. Contrast that with 1032 EXPERIMENTAL piston aircraft that were given airworthiness certificates in 2009 in the U.S. alone. Of those 1032, well over half were RV's!

The tie down assembly also doubles as the attach point for the aileron pushrod brackets as seen below.

Working on Tie Downs

Tie downs are the metal rings that hang down under the wings where you attach ropes or chains to hold the aircraft firmly on the ground when it's parked. Small airplanes are surprisingly light. An average completed RV weighs around 1000 lbs. That's not much when you consider they have a wing span of 25 ft. A strong gust of wind can tip over most small airplanes if they're not tied down. The two large rectangles of metal get bolted to the main wing spar and the rings are screwed into the bottom. You can see how it works on the plans in the upper right corner of the photo below. These can also be used as jack points for lifting the airplane.

The shiny rectangles of aluminum with the holes in them (bottom right in picture) are spacers that go behind the tie down brackets against the spar. I fabricated them from scratch and put lightening holes in them. Lightening holes are just a way to make things lighter without affecting the strength of the item. I like to tease the gullible that lightning (without the "e") holes let the lightning out if you're struck by it.

Countersinks and Plate Nuts in Spar Flange

This is a wing spar with the attach points on the flange for the fuel tank. The fuel tank skin will be dimpled to fit into the shiny countersunk holes with screws holding to the plate nuts behind the holes. This is one of those steps that everyone worries about and tries to improve on Van's technique. I have to admit I was nervous drilling into that beautiful gold anodized spar. I followed Van's instructions exactly and they came out near perfect. I used the micrometer that Peggy and Stephen gave me to measure the outside diameter of the holes with the target being .365-.375 and they were .370! The more I build, the more I realize that Van's instructions work great and that I'll need a compelling reason to deviate from them.

This is a plate nut that's behind one of the countersunk holes you see in the picture above. A plate nut is simply a nut for screws or bolts that can be permanently attached to the underlying surface. This one has two wings on either side of the threaded nut with holes in them that are riveted to the flange. There are quite a few different flavors of plate nuts like ones with one long wing with both rivet holes on the same side or 90 degree corner ones but this is the most common style.

Wing Plans

Time to start diving into the wing plans. Here's one of the pages from the wings. Definitely more stuff but I haven't seen any new skills required. Just lots of drilling, deburring, dimpling and riveting.

Wing Inventory Complete

Shelby helped me finish the wing inventory and also helped me find a place for all the parts. None of the big pieces were missing or damaged in any way. Good job packing, Van's! There were a few rivets and bolts missing (out of thousands) but nothing serious. I called Van's about a bag of wrong size rivets and they said to call when I finished inventory and they would replace them and anything else missing at no charge.

Here's how we used the long skinny (16') box. I mounted storage brackes to the ceiling and Sheby and I just put the box sitting sideways on the brackets. Simple and provides plenty of storage for long items like the longerons (used in the fuselage) and it's up high and out of the way but easily accessible. It's a challenge building in a two car garage while keeping room open for Paula's car.

Paula Helps Inventory the Wings

We dove into inventorying the wing kit and made it through the long skinny box. It's not a great picture but here's Paula checking off items for me as I dig them out of the box.

Sorting Hardware

Wow, there are a lot of little parts that go into the wings. I spent about 5 or 6 hours inventorying and sorting all the rivets and bolts and bits into drawers. It was a lot of work but it will make it much easier to find what I need when I need it.

Wings Delivered

The wings are here! FedEx Freight did a great job. They arrived 10 minutes before their scheduled delivery time and the crates were in perfect condition. I had my camera ready to photograph any damage but there wasn't any. The boxes were even oriented with the arrows up. I've read about crates being delivered by other freight companies that were half destroyed. My neighbor, Tim, was nice enough to help me unload them. I was a little disappointed that he didn't accept my offer of a Shiner Bock. Here they are between the stands I'll mount and build them on. I have 30 days to inventory and report any discrepancies to Van's. I will certainly have plenty to keep me busy for quite a while. As my Dad said, "that will sure keep you off the streets".