After 6 months of piecing together the tail cone, the big day has arrived...to take the whole thing apart. All those holes that Mike has drilled have created about a billion metal shavings and chips that need to be cleaned away.
This is always a disheartening part of the build. You finally have something that looks like part of an airplane, then you disassemble the whole thing into a big pile of parts.
Six months to put it together, 90 minutes to take it apart. Also, you can see how filthy the pieces have gotten after six months.
With everything disassembled, Mike finally cut off that extra triangle at the front of the tail cone skin. I hovered nervously and snapped pictures like crazy.
I'm sure I've mentioned this before, but sometimes during the build you come across a single line of instructions that you know is going to take forever. This single sentence of instructions took us a month to complete.
Deburring is by far the most boring, time consuming part of the build. We use drills with special deburring bits as much as possible.
In some places, there's not enough room for the drill, so you remove the deburring bit and use it by hand. When I say by hand, I literally mean put the bit in place and twist it with your fingers. To make it even worse, you have to deburr both sides of every hole you drilled, so you deburr twice as many holes as you drill. I have no idea how many holes we deburred, but I did count while I was deburring one of the smallest bulkheads at the back of the tail cone and there were 68 holes in that piece alone. My conservative estimate is that we probably deburred 2,000 holes. Mike also deburred all the edges of the skins, which wasn't done earlier. In total, it took us 16 hours to finish that single step of the instructions.
The instructions for the tail cone seem to jump all over the place. You feel like you're making real progress and then you stop what you're doing to work on some small, unrelated task. Obviously, every step is important, but it feels like we are always getting sidetracked.
We still had a few of those small tasks to complete before we were able to move onto the next major stage of the build. We drilled some shockingly large holes in the side of the tail cone for something called a static port. The static ports are part of the system that measures the plane's airspeed and altitude (thanks Google). The rest of the system will get installed somewhere down the road, but this is the best time to put those ports in place.
To drill the holes for the ports, Mike used a step bit. It looks kind of like a pyramid where each step makes the hole a little bit larger.
The step bit also has a straight cutting edge (you can see it on the bottom side of the bit in the previous picture) and that's helpful when you're cutting through the really thin metal of the skin.
Next, we installed the small plates that cover up the last of the holes at the end of the tail cone.
Finally, in one of the most confusing and frightening instructions, we got ready to cut off part of the skin at the front of the tail cone. There are two small triangles that stick out of the front of the tail cone. Apparently, you only need one of them when you attach the tail cone to the fuselage. Mike marked the section that will be removed, but we won't actually cut it off until we can get better access later on.
Okay, this is getting embarrassing. I have been so bad about updating the blog lately. We've been making steady (if slow) progress on the plane over the past few months, I just never seem to sit down and write about it. Let's start getting caught up on what's been going on.
At the end of my last post, Mike was just beginning the daunting task of final drilling all the holes in the skin and underlying support structure. It took him about 9 hours to drill all the holes, with the holes in the longerons taking a particularly long time. The metal of the longerons is pretty thick and unlike most of the other parts, there were no prepunched holes. I mostly stayed out of the way during the drilling process since it's really a one person job.
Once all of those holes had been drilled, we were ready to put the top skins in place. Before we were able to do that, we had to separate a thin strip of aluminum from one of the skins. I think that Mike said we will use that aluminum strip when we attach the tail to the fuselage...so about 5 years from now. I sure hope we can keep track of that piece!
The top skins are flat, but obviously the top third of the tail cone is not, so getting the skins in place was a bit of a process. First, we had to flute some of the flanges where the curve is tightest. The fluting introduces a slight angle into the flange so you can get a smoother curve. Without the fluting, you end up putting tiny creases into the skin as the metal of the skin bends at the end of each of those flat flanges.
The top skin is really two separate parts, so we started with the rear portion. We secured the skin at the flattest point on the top of the tail cone and slowly worked out way down each side, fastening the skin in place with clecos as we went.
We did exactly the same thing with the front section, until it looked like this.
With the top skins in place, there were more holes for Mike to drill. Then we continued work on the very back of the tail cone, where the horizontal and vertical stabilizers will eventually attach. You can see in some of the previous pictures, that there are still C-clamps holding together the very rear portion of the tail cone. Mike was finally able to drill some holes back there so we could replace the clamps with clecos and add some additional structural stuff. There is so much going on in that last few feet of tail cone that "structural stuff" is about as detailed description as I can give. Keeping track of all those little brackets and angles and support whatevers is going to be a challenge.
That structural stuff required using the angle drill in a couple of spots where the vertical stabilizer attachment bars get in the way of the regular drill. It was the first time I remember using the angle drill on such thick pieces of metal, and it was kind of a fiasco. The entire head of the angle drill swivels, so Mike struggled keeping it perpendicular while he drilled. At least one hole got a little mangled, but not enough to be a problem later on.
Then, we had to remove the top skins (of course we did) so we could install the seatbelt attachment brackets (technically they are called shoulder harnesses, not seat belts, but I don't really care). I still don't understand why we couldn't have done that step before we put the top skins in place. They don't look like much right now, but those seat belt brackets are the first real reminder that actual human beings will be riding in this plane.
I can't believe it's been 2 months since my last post! Time has flown by and I honestly haven't spent much time at the hangar lately. We moved into a new house in June (much bigger and closer to the airport!) and that took up most of our time and energy for several weekends. When Mike said he'd like to spend some time over the long weekend working at the hangar, my response was "oh yeah, I forgot that we're building a plane." I don't want to give the impression that no work was done on the plane in the past couple of months. My memory of some of these steps is a little rusty, but I'll do my best to catch you up on what's been done.
After we got the skins in place, Mike drilled holes into the stringers, using the line we drew down the center of each stringer to make sure that they were in the proper location. Then we had to level the tail cone so we wouldn't introduce a twist into the plane as we added some reinforcing structural pieces.
Next we added some pieces that will eventually be part of the rudder controls. They were pretty challenging to install since they narrow end of the tail cone is, well, narrow. Mike had to use the really long drill bit.
Then we were able to add the top half of the bulkhead at the very front of the tail cone and put the longerons in place. The longerons have to be lined up perfectly flush with the edge of the skin and it took some fiddling to get everything into place.
There's a cap (called the aft deck) that goes on top of the skinny end of the tail cone. It has lots of holes cut into it, I'm assuming to accommodate all of the mechanical elements needed for the tail. Sometimes it's hard to remember that the entire tail of the plane is going to attach to the narrow end of the tail cone. No wonder it has so many reinforcing parts! Before we could put in the aft deck, we had to create a spacer to fill in one gap. The instructions said to attach it using carpet tape, and it worked pretty well. I imagine we will be drilling holes in it at some point down the road.
We clamped the aft deck into place - good thing I have small hands because there's a lot of structural components in that small space.
At this point, we realized that the notches in some of the forward bulkheads were rubbing against the longerons. Mike took care of that with a little careful filing.
And then, Mike spent hours and hours and hours drilling holes. By my rough estimate, he probably drilled 1,000 holes in the skins, bulkheads, and longerons.
This past couple of weeks has reminded me of two important plane building lessons. 1) A task you expect to take one hour will actually take two or three. 2) Even if you're frustrated with some part of the build, you'll eventually figure it out. Honestly, what other option do you have but to figure it out. It's not like you're going to throw away the past year and a half of work and give up.
I was reminded of these lessons when we tried to fit the other side skin onto the tail cone. Theoretically, it should have been a piece of cake and taken about 30 minutes. In reality, it was one of the most frustrating experiences we've had so far and took more than a week to figure out.
Everything started smoothly, well except that we had to free up some work space before we could begin. Our EAA chapter holds a dinner every couple of months, which means the entire hangar gets rearranged to accommodate the crowd. Making enough free space for the tables is like a giant game of tetris. It's impressive how tightly things gets packed together and the space between our sawhorses and workbench was entirely filled...
So, before we could begin, Mike had to move another plane out of the way. Unfortunately, that task pretty much wrapped up the easy, successful past of our day.
We flipped the tail cone on it's side so we could more easily attach the other side skin.
In this picture it looks like we are building a canoe rather than an airplane. We were able to get the front bulkheads clecoed into place, but once we got toward the skinny end of the tail, there was a small but significant mismatch in the location of the holes on the skin and bulkheads. I would say that we were off by about half a hole, but there's absolutely no give to aluminum. If you can't get those two holes to line up, you're not getting a cleco in there.
This is what it's supposed to look like. Notice the row of clecos running vertically down the center of the picture. This is the side skin that we finished attaching last week.
This is what the other side looked like. Notice there are no clecos in that bulkhead that runs down the middle of the picture.
I tried to get a picture of the misalignment between the skin and the bulkhead holes, but the small size of the holes and reflective skin surface made it impossible.
We made a valiant attempt and tried to get the holes to match up for nearly two hours. We tried everything...
So, the next weekend Mike got out the grinder and set to work. Here's what the bulkhead looked like when we started.
Notice how square all of the tabs are, particularly the tabs on the far left and right sides of the bulkhead. That's what was causing our problem. You can actually see the creases that they left in the skin.
Mike very carefully and delicately used a grinder to smooth out the tabs and give them a more rounded profile.
Well, I assume he was very careful and delicate. There was nothing for me to do while he was grinding so I took a series of photos where Zoey was increasingly pathetic as she begged for popcorn.
Once we had reshaped the bulkhead, everything fit together perfectly. In minutes, we had the whole side skin clecoed into place.
Next, Mike has to match drill all of the stringers on this side of the tail cone.
We are finally ready to begin putting the tail cone together. There are points in the build process when I realize "holy crap, we are building an airplane!" and this is definitely one of those points.
Our first step was to dig the tail cone skins out of storage and peel off the blue vinyl. Rather than just remove the vinyl along the rivet holes, like we did on the vertical and horizontal stabilizer skins, we decided to completely remove the vinyl on the tail cone. There are so many rivet holes in this part of the plane that we would be removing 75% of the vinyl anyway, so we might as well just take it all off. It also means that the tail cone is very shiny and reflective, which makes it harder to take good pictures of some parts of the build.
This is also a great time to admire the sawhorses that Mike built. He debated for a long time about whether or not to buy prebuilt sawhorses or make our own. Ultimately, he decided to build them because the plans suggest using sawhorses that are a couple of inches taller than the standard prebuilt version. These home built sawhorses also have some other benefits that we discovered later on.
This skin is the bottom of the tail cone and once it was ready, we flipped it over so we could start adding the bulkheads. The bulkheads are basically vertical walls that provide structural support. These walls just happen to have large holes in the middle.
There are small notches cut out of the edge of each bulkhead and this is where those J-channel stringers get installed.
There are also some shorter stringers that run inside that bottom skin, but they were really hard to photograph.
Once the stringers are in place, we peeled the vinyl off the side skin and put it into position.
If you want a good arm workout sometime, come help us peel vinyl off these skins! It's hard work and takes much longer than you would expect. You'll also notice that the side skins have a curve in one side. This curve forms that bottom edges of the tail cone. Here's a side view where you can see how the stringers run against the side skin.
This is also where we discovered an added benefit of our home built sawhorses. Once the side skin was in place, one side was much heavier than the other and we were worried that it would fall of the sawhorses. There's an additional structural component at the widest end of the tail cone called the "bellcrank ribs". I have no idea what a "bellcrank" is or why it needs ribs, but their inconvenient locations meant that the sawhorse had to sit about two feet from the end of the tail cone. Because our home built sawhorses are made of standard 2x4's we were able to do this.
Instead of a solid 2x4 across the top of the sawhorse, we used two smaller scrap chunks of lumber and were able to create a gap for those bellcrank ribs.
At this point, I left the hangar for several hours while Mike match drilled holes in all those stringers. I don't know that I've explained match drilling yet - it simply means that there are already holes in one part, in this case the skins, and you need to drill matching holes in some underlying piece, in this case the stringers. Remember those lines we drew down the stringers in my last post? Those lines help Mike make sure that the stringers are in the perfect location when he drills the holes. It took hours for Mike to drill all those holes and when I came back to pick him up, this is what it looked like.
Our final step of the day was to flip the whole thing over...
Next, we will add the other side skin.
We've spent the last three work sessions completing some very time consuming projects. There hasn't been a lot to show for the hours we've spent at the hangar, but I'll bring you up to speed on what's been happening.
After we finished with the stiffeners, we got to move onto the longerons. A longeron is just another structural component in the tail cone and fuselage. In this case, it's a long "L" shaped piece of aluminum that runs the entire length of the tail cone. Wikipedia tells me that there honestly isn't much difference between a longeron and a stringer (the long pieces of aluminum we worked on last week). They serve exactly the same function, but longerons tend to be a bit heftier than stringers. Also, the word "longeron" is much more fun to say.
The longerons had to be notched so they wouldn't rub against some of the other structural components of the tail cone. The notches have to be cut in a very specific location, which required a bunch of careful measuring and remeasuring. Then we drilled some small pilot holes before drilling the final 1/4" holes.
I mostly stood around the took pictures during this process. As I saw the spirals of razor sharp metal that Mike was creating as he drilled the big holes, I realized I wasn't wearing my safety glasses. You definitely wouldn't want something like this to fly into your eye!
Once the holes were drilled, we marked out the additional area that needed to be removed. Mike removed most of it with a saw and we finished up with a file.
Everything went smoothly, but since we were very careful during this process it took us about an hour to finish two notches. Now we will just hope that they are in the right place. We won't really know until we put everything together.
The next task we had to complete was bending the longerons so they line up with the edges of the tail cone skins. There is a 2° angle in the skins that we had to try to match. You can just barely see the angle in this picture.
To bend the longerons, we used the old "preload" technique from my last post. Or, as I prefer to call it, push on the metal and whack it with a hammer.
This is quite a bit harder than it looks. The "L" shape of longerons means that they have a tendency to bend in two directions instead of just one. In this particular set of pictures, that means the longeron is bending away from Mike as he whacks it with a hammer, but is also bending down toward the floor. The whole thing is a process of trying to get the 2° bend in the direction you want and then remove the extra bend that you didn't want. We got it figured out eventually, as you can see in the bottom pictures. It took forever to bend the first longeron, and about five minutes to do the second one.
The final prep task we had to finish was draw a line down the length of the J-channel stringers we previously cut. This line has to be precisely 5/16" from the edge. The problem we had to solve is how to draw a line exactly 5/16" from the edge all the way down an 8 foot long piece of oddly shaped aluminum. Mike, of course, had a clever solution that I, of course, thought was ridiculous at first. I'm pretty sure when Mike described his idea I laughed, mostly because I didn't even remotely understand what we were trying to do.
Mike's idea was to create a jig with a hole drilled in it.
You put a marker through the hole and very carefully slide the jig down the length of the stringer.
It was pretty awkward to use because the only flat surface in the J-channel is where we need to draw the line. I eventually got the bright idea to rest the J-channel on the miter box Mike built to trim the ends off the stringers and that worked much better.
These lines will eventually be used to make sure the stringers are in the right place while Mike drills holes. By centering the line in the middle of the predrilled holes in the skins, you can make sure that your stringer is in the perfect location.
With these last pieces finished, we are ready to begin construction of the tail cone!
We've been prepping more parts for the tail cone and most of the work has been very tedious. There have been more hours of deburring than I care to think about. Occasionally we get to figure out some new skill, like how to remove the bow from some very thick pieces of aluminum.
There are two heavy aluminum bars that will eventually attach the horizontal stabilizer to the tail cone. At least, that's my educated guess based on the fact that the pieces are called "horizontal stabilizer attachment bars." They are pretty badly bowed from the manufacturing process and we had to straighten them out.
You can really see how much room there is between the left side of the piece and the workbench. It's not as noticeable on the right side, but the whole thing is curved like a dish at this point.
The instructions make the process sound much more technical than it really is. To remove the bow, we "pre load the free end of the attachment bar in the direction required to straighten it and, using a rubber mallet, firmly strike the bar one time near the vice." In laymen's terms, you put the bar in a vice, push against the end (that's what they mean by "preload") and whack it with a rubber hammer.
You do that over and over again, moving the bar as you go, until it is straight. Here is a comparison between the bar that has been straightened (on the right) and the one that hasn't (on the left).
Mike has also been cutting varying lengths of J-channel, which is a long stick of aluminum with a profile that's roughly shaped like the letter "j".
These pieces of J-channel will run the length of the tail cone and act as stiffeners. Mike cuts the 90° angles on the bandsaw and smoothes the edges with a bench grinder. Some of these stiffeners have be cut on a 45° angle. Because of the orientation of the 45° cut, the bandsaw won't work for these pieces. We don't have many saw blades that will cut aluminum and instead of buying a $50 saw blade, Mike came up with an inexpensive solution. (I know, I'm as shocked as you are! Mike actually resisted buying a new tool!) He built a mitre box out of some scrap lumber and bought some $10 metal blades for his hacksaw. He smoothed the ends of the shorter lengths using the bench grinder, but some pieces are nearly 8 feet long and he used a pneumatic hand grinder for those.
While Mike was manufacturing various parts, I deburred my little heart out. We are almost ready to get out some tail cone skins and start fitting things together. I can't believe how quickly things have gone so far...but that could be because I skipped several work sessions at the hangar while Mike either worked alone or got help from his buddy, Keith. It's always amazing how fast work gets done when you're not the one doing it. I've still put in about 6 hours of deburring but easily missed out on just as much. Here is a portion of the parts that have been assembled so far.
After a week of basking in the euphoria of finishing the horizontal stabilizer, it was time to move on to the next portion of the build - the tail cone.
But first, we had to move the horizontal stabilizer into storage. That task wasn't as easy as expected because 1) the hangar where we are working is packed full of stuff and 2) the horizontal stabilizer is nearly 12 feet long. It's not especially heavy, but it's very awkward to move. After moving a LOT of stuff out of the way, we made a clear path and got the horizontal stab all settled into storage.
With the horizontal stabilizer out of the way, we were confronted with a view that we haven't seen in a really long time.
That, my friends, is an empty workbench! Don't worry, it didn't stay empty for long. While we were stowing the horizontal stab, we grabbed the parts that we will need for the first stage of the tail cone.
It's been 10 months since we started a new section of the build and I had forgotten what the early stages are like...peeling vinyl, marking pieces, and deburring! Deburring is one of those tasks that just never seems to end and these tail cone pieces are full of lightening holes, nooks and crannies. It also seems like every piece is curved and has a million flanges. I did manage to get a pretty good picture of why we have to deburr every single edge. You can really see how rough the edges are on the flange.
While I spent hours deburring, Mike started work on the first pieces of the tail cone. The first few pages of the tail cone instructions also require us to fabricate quite a few pieces. Mostly, they instruct us to cut a short length off of a long piece of metal and drill some holes. Mike likes to cut the pieces a little bit long and then finish the ends using the bench grinder.
The holes always need to be drilled a very odd, very precise distance from the edges. I thought Mike used a very clever system to get the holes in the right spot. He laid down a solid layer of black sharpie and then used a scribe to make a line the appropriate distance from each edge. Where the scribed lines make an "x" is where he needed to drill.
The holes that go into this particular piece are absolutely enormous (compared to every other hole we've drilled so far). When Mike got out the drill bit I made him double check the size a couple of times before I would let him make a hole.
When we were done, we realized that the holes weren't in the right place. They were each off by about a quarter of an inch, so we started over and did the whole thing again. Even when building airplanes you should measure twice.
These big holes then needed two smaller holes drilled on each side. We will eventually rivet on a nut plate that does...something. I'm going to admit right now that I have absolutely no idea what any of this stuff is. When we worked on each of the stabilizers I got pretty comfortable with the types of pieces we were preparing and using. On the tail cone we seem to be prepping a whole bunch of parts that then get set aside. I honestly have no idea what's going on, which makes it very hard to explain. As this part of the build progresses, we will just have to figure out what is going on together. Anyway, here are some pictures of drilling the holes for the mysterious nut plate.
We have (finally) reached the point where we can attach the rear spar to the horizontal stabilizer. It's been a long, long, long, road to this point. If you had told me that we would spend 10 months working on this part of the plane, I would have never believed it.
We only have two steps left before we can officially declare this part of the build finished
...and we have to fix that terrible rivet I showed you last week.
We decided to wait awhile before we tackled our riveting mistake. We needed time to contemplate our options and maybe ask for a little advice from some more experienced builders.
In the meantime, we started attaching the rear spar to the ribs using pop rivets. Once the rear spar is in place you can only access it from one side, so pop rivets are the only option. The nice part about pop rivets is that they are pretty hard to mess up. Don't get me wrong, you can definitely mess them up, but there are fewer ways that they can go horribly wrong. The worst part of this step was that we had to ream almost every single hole before we could set the rivet.
The six rivets that are in the center of the horizontal stabilizer are accessible from both sides, so we used regular rivets in that location. When we squeezed the very first rivet, we didn't notice that the rib flange was pulled away from the spar. You could see the rivet bulge between the flange and the spar, so it had to come out. We went about that in the regular way - drilling out the head of the rivet and then using a punch and hammer to drive out the shaft.
That's when things went wrong. As we (should) have learned many times, a small mistake can turn into a much bigger mistake very quickly. When we tried to hammer out the rivet shaft, this is what happened to the flange.
Oops! As we hammered out the shaft, the bulge in the rivet got stuck on the flange. As the rivet moved, it pulled the flange with it. At this point, our only option is to fix mistakes as best we can, so we tried to bend the flange back to it's original location. First, we put two flat dies in the squeezer and tried to flatten things out by squishing the flange back into place.
That helped a little bit, mostly to flatten the area right around the rivet hole. Next, we tried to use clamp to push things back together.
I may have mentioned once or twice (or a hundred times) that there isn't much room to work in this area, so we had to find a small enough clamp to fit. The clamp helped straighten things out, but it left quite a few scratches on the flange and spar. There was no way to bend the flange back to exactly where it should be, so we decided we would have to use the clamp to hold things in place while we replaced the rivet. We used some tiny pieces of scrap wood to protect the aluminum from the clamp.
This is the end result of all that work (after we installed the other two rivets).
Honestly, I'm not sure that it looks much better than it did originally. Mike says that the final product is better and after all the trouble we went through, I'm going not going to argue.
The final step was to attach the rear spar to the skin. It was probably the easiest thing we've done on the plane in months. Not a single thing went wrong and Mike actually finished half of the rivets on his own while I was at work last weekend. He could have easily finished all of the rivets but (wisely) waited for me so we could finish it together.
Normally, this would have been the point where we declare victory, but we still had that one rivet to replace. Remember, it looks like this...
We've spent the last two weeks debating how to remove this rivet. The manufactured head is so deformed that we couldn't tell where the center was. Mike posted this photo on a builder's forum that he frequents and asked for advice. People suggested that we drill though the shop head on the other side since it is in good shape. We considered that option, but decided against it because even if we removed the shop head, there's no room for a hammer and punch to remove the rest of the rivet.
Finally, we decided to very carefully perform airplane surgery and attempt to remove the mangled manufactured head. Mike wanted to get a better look at what we were working on, so we put the horizontal stabilizer back into the wooden cradles, upside down.
Mike used calipers to measure the distance between the center of two rivets (on the side we didn't mess up) and we used that measurement to try to determine where to find the center of the mangled rivet. Then, he used a tiny metal file to try to flatten out the head near the center.
While Mike worked, I hovered, took pictures, and tried to act as the voice of panic/reason. After a while, we laid the horizontal stabilizer on it's side again and Mike used a punch to make a divot where we thought the center of the rivet would be. We used the shortest, smallest drill bit we had (which only fits in the angle drill) and attempted to drill out the center of the head. Then he carefully used a hammer and punch to break off the least mangled half of the head.
After half an hour of work, this is what we removed.
And this is what was left.
We still couldn't tell where the center of the rivet was, so we had to keep working on it. I'm typically more patient that Mike when it comes to fiddly work, so I spent 20 minutes very carefully filing away at the remaining head.
The only evidence of progress I had was a slowly growing pile of tiny metal shavings. Eventually, I had removed enough metal that I was able to slide a razor blade behind the thinnest part of the remaining head, bend it forward and pull it off with pliers. We decided that we couldn't file away any more metal without damaging the flange, and while it was still impossible to tell where the center of the rivet was, we were able to make an educated guess.
Technically, you only have to remove the manufactured head before you can punch out the shaft and shop head. Since we didn't know where the center of the rivet was, we used a smaller punch than usual. The idea was that even if we weren't dead center, we would be less likely to punch a hole through the flange while we hammered out the rest of the rivet. Using a smaller punch didn't work out quite as we had planned.
The punch bent and the rivet didn't move at all. We decided that we would have to be brave and attempt to drill out some more of the rivet. Luckily, we actually managed to hit the center of the rivet and were finally able to get the rest of the rivet out. It didn't look to pretty by the time we were done.
After our previous attempt to remove a rivet from this part of the plane, we weren't too surprised when the flange bent as we removed the rivet. Just like last time, we used a clamp to straighten things out as much as possible. Then we used a small piece of rubber hose over the shaft of the rivet so I could keep the flange in place we installed the new rivet. It actually looked pretty good by the time we were finished. We are definitely getting better at fixing our mistakes.
After all that work, we triumphantly declared ourselves finished with the horizontal stabilizer! We now have 2/5 of an airplane tale!