Trial Run

We had another one of those quirky Global Warming days today - 60+ degree days in January continue to make me wonder what precisely is wrong with a little bit warmer globe, although if asked in August I will probably be able to come up with a pretty good answer. It would have been foolish to waste the opportunity as the forecast for tomorrow takes us right back to the normal miserable wintry crud we usually have.  

Truth be told, it is tomorrow's weather that better reflects my current mood - three weeks into a six week audit and I have had enough of probing and repetitive questions. Don't get me wrong - there are very good reasons for these folks to be in here looking at my stuff - but it gets difficult when they demand evidence of something that happens invisibly. For example, the applications that I build determine who the user is and what that user should be able to do (or, more importantly, not do) by "asking" Windows who that user is and what groups he/she belongs to. This is great for me because it lets me trust Windows to manage their passwords - no more "Dave, I lost my password!!" interruptions to deal with. Corporate HQ also sets and enforces the password complexity rules, so I am automatically in compliance with their standards through no additional effort at all. It works wonderfully, right up until an auditor says "Prove it!"

Sigh.

Still, a little warmth in the late afternoon this time of year is a gift and it would be churlish not to appreciate it to its fullest, so Pete and I gratefully took the opportunity to button up the plane. That meant removing the spark plugs and re-torquing them with heat sink compound on the threads, putting on the cowls, and finishing up the installation of the fuel filler neck. With all of that done, the plane was ready for flight except for two outstanding tasks: the brake pads needed to be conditioned, and the fuel level part of the Dynon needs to be calibrated. I was able to do one of those.

We pulled out the plane and I managed to get it started. Five times. I'm still not very good at the transition from choke to throttle and it dies on me until I get it just right. I called Bolton ground for taxi permission, but there was no reply. That can mean one of two things: the day has been so slow and boring that the controller has nodded off, or that the volume is turned down on the radio. Because the first is so common, it took me a couple of seconds to test for the second. I did it just in time to hear an irritated "two eight four delta golf, how do you hear this radio?"  Oops. He must have thought that his primary radio was broken, which is also not uncommon at Bolton.

I replied back that I could hear him just fine, the fault was mine, and that I apologize. Not  accepted, it would seem, because he was surly for the remainder of our interaction. I asked to taxi down to the runway where I would need to perform "a high-speed taxi." I realized too late that from where he sits, 40mph was not going to look anything remotely like "high speed," but given his mood I just let it go.

The winds were fairly light at 8 knots, but I still had trouble taxiing in a straight line. That huge weather vane on the tail combined with a swiveling nose wheel had me punching at the brakes the whole way. I think this airplane is going to go through brake pads at a prodigious rate.

The taxi test/brake conditioning went fine. The idea is to accelerate to 40 mph, brake hard down to 5 mph, repeat three times. By the third time, I was able to get the tires to screech a little bit, so it would seem that full braking authority was attained. I also had time to monitor the airspeed indication on the Dynon and see that it's working fine.

While taxiing back in, I tried to engage the tower guy in a little chit-chat by saying that "next time out will be the first flight!"

He replied, "                                              ."

Sigh.

Final Steps

As most of you are no doubt aware, N284DG has been deemed to be a viable flying machine in the eyes of the law. That said, the fellows coming to inspect it wanted to see some of the moving parts normally hidden away by various panels and covers. Those all had to be replaced, so four or five hours working out in the cold environs of the hangar were required. Even then it still wasn't completely put back together, but it was far enough along to take some pictures of it in the most complete state it has been in for months.

So, you're probably wondering, what's left to do? Well, I'm glad you asked.  First of all, the fuel tank level needs to be calibrated. I had to remove the tank to replace the back bulkhead, which means that I had to drain out the two plus gallons of gas in it. The tank is now back in place, but it's empty. That's good, because the way the tank is calibrated with the Dynon is to put in two gallons at a time, pressing a button on the Dynon between each filling. It will take, therefore, ten repetitions of filling a little two gallon jug and carefully pouring it into the tank. If that doesn't sound like a whole lot of fun, it's because it isn't.

Then the cowls have to go back on, which is again no one's idea of a good time. In addition to which it will require some assistance - I'll need to schedule a session with Pete. On the plus side, it's supposed to get unseasonably warm again later this week.

Once it's all re-assembled, I'm going to fast taxi it down the runway a few times. That will double as my brake glazing operation. The primary function of it, though, is to make sure the wheels all roll nicely. Oh, and that none of them part ways with the rest of the airplane. That's important too.

After that it will be ready to fly, even if I am not. I've been thinking about the first flight quite a bit. Van's would have me get started on the flight test cards (which are intended to be used to gather information about the performance of the plane) on the first flight, but I'm thinking I won't. Van's tends to group-think quite a bit, and they are a group that seem to see nothing particularly special or difficult about a first flight. I think I will probably be a little too wrapped up in the intense experience of the even to be wanted to concern myself with measurements and writing stuff down.  

Their attitude is understandable, of course, since they live and breathe this stuff five days a week.  They're kind of like that with challenges to the build process too. They seem to forget that we aren't all working in large, temperature-controlled, well-lit facilities with every necessary tool right there for the asking, nor are we just a few steps away from the guy that can provide clarification for an ambiguously worded step in the plans. This manifest itself at times in the way they (well, some of them anyway) respond to questions and complaints.

Anyway, I see the first flight as an opportunity to get a feel for the plane and get used to the idea that it will actually fly. I'm planning on asking the tower to let me stay in the traffic pattern to the west of the airport (that's where all of the open fields are) as I climb to 3,000' or so. Once there, I'll fly a few orbits around the pattern before descending back down for my first landing. Then it's back to the hangar to open it all up again and make sure nothing worked its way loose.  I think I'll also drain out the full-synthetic oil that's in it now and replace it with semi-synthetic Aeroshell. That will allow me to burn avgas which, while more expensive, is better suited to my current need. That need being, as it turns out, a way to get gas into the plane without having to carry it home from the gas station and fill the tank by hand.

My flying area for the first five hours is limited to a radius of fifty miles around my home airport. That will be plenty. I probably won't get through the test cards in four and a half hours, though. There's quite a bit of data to be gathered.  We'll talk about that later, though.

The Inspection

It is done and, at least in the eyes of the Federal Aviation Administration, N284DG is an airworthy airplane.

Physics and aeronautics still get to weigh in, of course, and as potentially far harsher judges, but that hurdle has yet to be reached.

It's fitting, in a way, that the inspection should occur on a morning with temperatures hovering around the 10-15 degree range when you consider just how much of the work on the airplane was performed under similar conditions. Kyle, Chief Thermal Engineer for The Jackson Two, flew up in his own RV-12 to deliver a heater to aid in keeping the Feds happy, himself surely remembering the bitter cold January night a few years ago when he and his father riveted the skins on my tail cone before taking the leap into ordering their own kit.

Unfortunately, in this case the end result of his effort was to metaphorically bring a toothpick to a gunfight; the poor little thing didn't make a dent in the all-pervading deep freeze.

Still, it's the thought that counts and I appreciated the effort. The inspectors arrived a few minutes before the appointed time and got right to work. I wasn't sure what to expect with the conditions being as unfavorable as they were and found myself torn between wishing for something along the lines of "Yep, two wings and a tail - let's get inside for the paperwork" or a full-blown, find-anything-that-could-potentially-hurt-me inspection. It ended up being somewhere in the middle.

We started with the paperwork required for things that involve the actual operation and maintenance of the airplane. In my case, that meant showing them the Pilot's Operating Handbook (POH), the Equipment List, the Weight & Balance calculations, and the Maintenance Manual, all of which were provided by Van's as part of the kit. It's fantastic that these things are included with the kit because it would take hours and hours to do them from scratch.

For the weight and balance, I showed him the Empty Weight page where I had entered the weight and balance numbers I calculated back when we weighed the plane. I also had worked out two sample weight & balance sheets. I made one for minimum weight (just me), and one for gross weight. For each of those, I did the w&b calculation at both max and reserve fuel. The point of this was to demonstrate that the plane stayed within limits at the endpoints of the loading continuum which should address any concerns about how the plane is loaded.  It's important to know this because there are planes that can fall out of the CG range just by burning off fuel - you could take off just fine, but somewhere mid-trip you'd find yourself in trouble.

They then asked me something about the POH that somewhat confused me -- they wanted proof that the one I had was the correct version for my type of airplane. I wasn't sure how I would comply with that, but Kyle helped  by pointing out that my POH is labeled 'RV-12 Skyview' and to date, there are only two types. One of them was very interested in the Equipment List and asked me to identify what each item was. I only got stuck on the 'Odyssey PC3' (or something like that) for a moment until I realized that it's the battery.

The physical inspection of the airplane took fifteen to twenty minutes and resulted in them finding nothing more to comment on than a tie wrap that I should re-do in a slightly different way. They professed to be impressed with the quality of the build, but I think that's really more of a testimonial to the quality of the kit. The only thing I can honestly take credit for was the bundling of the wires behind the panel.

Once we got to the point where the presence of the airplane was no longer required, we moved indoors for the completion of the paperwork. Unfortunately, this was their first experience with E-LSA paperwork and they had listed me as the builder in a number of places where it should have listed "Van's Aircraft, Inc."  There were a few more issues as we got deeper in the pile of documents and it eventually got to the point where it seemed that the best course of action was to drive over to the FAA offices to have some of the forms re-done.  

Yes, I was going to have to go to the FAA office! It didn't escape me that this is an occasion that is probably somewhat rare in these inspections, absent a blatantly felonious act. Still, I thought it would be nice to get this out of the way rather than make a bunch of after-work trips later in the week, so I agreed. Into the car and off to Port Columbus we went.

Kyle and I got to their office first and had to sign a guest log and receive a little paper badge to wear. We told the receptionist who we were there to see and she was just starting to reply by telling us that he was out of the office when we heard a voice of disbelief from someone just getting ready to come through the main door:

"And they didn't even have a heater??!?"

I turned to the receptionist and said, "There he is."

Sure enough, the door opened and there were my two inspectors and the temperature-sensitive co-worker.

They escorted us to a conference room and finished up the corrected paperwork.

With the final form finally signed, N284DG officially became an airplane.

Pre-inspection wrap-up

The inspection is scheduled for Wednesday morning and perhaps not surprisingly, this has provided a much-needed impetus to wrap up the loose ends that have accumulated over the course of the last few months.  Because the inspectors are going to want a lot of the panels and floorboards removed, I went ahead and tore everything back apart after the carb syncing operation. Having everything opened up again offered Pete and me the chance to take another close look for things in need of tightening up and/or things that may be rubbing inappropriately against other things.

You know, like high school dance chaperones.

For the most part everything was pretty well put together, but with this being the first time that the tail cone has been removed since the day it went on it wasn't too much of a surprise when Pete found a screw/net pair loose on the trim motor tray. It must have always been thus; given that the airplane has never flown, it was very unlikely to have been caused by vibration. It is far more likely to have never been tight, and the experience of trying to tighten pointed out why. The nut is one of the tiny little metal locknuts that have given me so much grief whenever I have to deal with one of them. I don't have a wrench small enough, and pliers aren't strong enough to hold them. I did find that I have a 1/4" drive socket that will fit, though, so we were able to get it snugged up.


This experience reaffirmed yet again the tremendous value of having a second (or third, fourth, fifth...) pair of eyes looking things over; they see things as they are, not as someone like me sees what he's used to seeing.

One of the other little to-dos was to put a tail number identifying tag on the panel as required by the set of FAA regulations designed to assist the guy that steals your plane. I will eventually get a nice engraved tag, but for now it is a printed piece of paper held in place with packing tape. I installed it with the same preternatural skill at getting things dead level that was so well demonstrated by the installation of a new mandated tag on the transponder that is required by the update of the Skyview firmware to version 5:

I'm also to the point where I really need a tow bar. Moving the airplane around without one is difficult and to some degree, risky. It doesn't always go where I want it to go, and the moment arm on the tail is such that it wouldn't take a great deal of untoward swing at the front to cause crushing amounts of damage in the rear.  I looked around (since I'm not keen on the $100 offering from Van's) and found a suitable candidate at Lane Aviation, right here in town. They're located at Port Columbus, though, and it's moderately hasslesome to go there, so I called ahead to make sure they had one. The warning hairs on the back of my neck prickled a bit when the answer was "The computer says we have one," but against my better judgement I went anyway.

Naturally, they didn't. They would have to order one. One the plus side, they will have it shipped to my house without charging me for the shipping. Also scoring high in the plus column was this terrific find:

Note that while I am using this as a much-needed pitot tube cover, that is not what it really is. When it is doing its intended job, it protects the static wicks on Cessna business jets. It was a bargain at $7.15 if it was even possible to find a cover specifically designed to fit the odd size of the RV-12 pitot tube.

I also took the opportunity to check the compression levels on all four cylinders. I was pleased to find all four to be exactly the same, although I was somewhat surprised at their low level as compared to a more traditional engine like a Lycoming. Note that I am testing at the lower value of the 80-87 psi range called out for the Rotax, but still - I've never had a cylinder lower than 78/80 on the RV-6 and the Rotax cylinders are all 74/80.

Carb Syncing

So, here we are right smack in the middle of January, suffering through the season of... wait, what? Sixty-plus degree days?? Well, that isn't so bad!  Sure, the day job is fraught with stress and peril, what with corporate office auditors in the house for the next month or so (and hey, when did audits go from being 100% shouldered by the finance folks to them only getting 20% of the attention and the poor IT Director getting 80%???), but the clement outside temperatures are sure coming in handy. This is their first day here and I'm kind of on call, but they've disappeared for lunch. I figured I'd fill the time waiting for them to come back by writing a little update.

The unexpectedly warm weather is very welcome as I had been mortally terrified of standing behind a propeller turning at 4,000 RPM and producing a wind chill of something like minus two hundred degrees while trying to make small adjustments to a throttle cable, but as it turns out I worried needlessly. First of all because of the temperate climate, and second of all because I was able to foist that job off onto someone else. Well, to be fair, he really knew how to do it, having done it once already, and I had no clue at all, so it made perfect sense. But still, there I was sitting in the warm dry cockpit while he stood out in the elements (exacerbated by a touch of rain) adjusting the throttle cable -- it's hard not to feel at least a little bit guilty about that. That said, I'm doing an admirable job of it.

I suppose I ought to explain this whole carb syncing thing. As you may or may not know, there are two carburetors on the Rotax 912 engine. And, as I've always said, "My dad always told me to stay away from two things: blondes and carburetors."  He never actually said that, but that inconvenient little fact has never dissuaded me from sharing that little tidbit of parental wisdom. After all, it has been my life-long experience that he should have said it, even if he didn't.

The thing about having two carburetors is that they have to be very closely aligned with each other lest a dangerous vibration occur as a result of two cylinders receiving more or less fuel than the other two. This synchronization is achieved by inserting a pair of pressure sensors between the two carbs. That feat is performed by plugging a device containing the requisite pressure sensor/displays into the crossover tube that normally connects the two carbs. The answer to the now begged question of just why a crossover tube is needed to connect the two carbs is an exercise left for the reader, which is academia's way of saying, "Beats me."

And so it transpired that The Jackson Two, them having already performed this operation on their airplane in addition to having purchased a more expensive and more sophisticated electronic tool for the job than the mechanical version I bought, made the trek up north to assist in the synchronization effort. In the rain, as it so happens. Unfortunate, that, but probably more desirable than in the bitter cold. The view of it was terrific from my seat inside the airplane, and the wind was no bother at all.

This job quite naturally entailed the operation of the engine, a fact that forced me to get back out to the hangar and finish up a few outstanding jobs before getting the fuel tank back in and replacing some removed panels. I also finished up a few of the remaining items on the to-do list, chief amongst them being the torquing of the nosewheel nut. This nut is what holds the nosewheel fork to the nosewheel gear leg, but it also serves the purpose of putting a little resistance in the directional turning of the nosewheel itself. Without any such resistance,

[pause] The phone just rang.

"Dave Gamble" (my standard gruff greeting, used to discourage cold-calls)
"Hi, this is (mumble) calling. Have you had a chance to read through my emails yet?"

Now, this is a standard cold-caller tactic in IT. They send my emails trying to interest me in buying stuff that I have no use for. I just ignore them, hoping that they will get the hint, but sometimes that's not enough and they actually call.

"Well, which of the many people that send me emails are you?" I asked.

"I'm calling about your RV-10. Aren't you the guy with an RV-10?"

Ah, I see. It's someone calling about buying the RV-6! Yay!!!

"Well, no, I have an RV-6 for sale."

"No, I thought you wanted to have an RV-10 inspected," he replied.

"Ooooohhhh! You mean the RV-12!  Is this John W.?"

And it went on from there. So, the inspection is scheduled for Jan. 23rd, 9:30 am.

I originally had asked for Monday the 21st, but he informed me that the 21st is Martin Luther King day.  And as I've always said, if you find yourself in a hole, keep digging:

"Oh, you get that day off? I gotta get me a government job!"

I have that day off too, so I was just joking around. We had a nice chat and I'm now pretty clear on what I need to do to get ready for the inspection.

[end pause]

Without any such resistance, the nosewheel would shake and shimmy uncontrollably during takeoff and landing.  The nut gets tightened until it takes 26 lbs. of force to get it to swivel. That's pretty easily accomplished with this handy little scale I bought at Walmart.

I also updated my Skyview firmware to version 5.0. I had been putting that off out of fear that it would break something in the avionics, but I figured the plane is just sitting there anyway... it went without a hitch. Worth it, too. The moving map graphics are much, much nicer with version 5. As long as I was at it, I updated the aviation databases, something that we're supposed to do every 28 days. I never did with my Garmin because it was far too expensive, but the Dynon pricing is far better: $0.00.

With the carbs synced, there's nothing left to do but take all of the panels off again to give the inspectors something to look at. I'm pretty confident that there won't be any big issues, and I attribute that to the quality of the kit.  There really isn't much to do wrong enough to render it non-airworthy. I anticipate things more along the lines of "You ought to secure this little wire" and the like. All easily repaired.

I was worried that I would need to get the transponder checked before they could sign the plane off as airworthy so I asked about it, but he doesn't think it's necessary. I think avionics are pretty much out of his realm.

Bleeding while Freezing

It's not always a good idea to look at the thermometer whilst on the way to the hangar to do some airplane work. Sure, you'll find out soon enough that it is way too hot or way too cold to be out there crawling around on the floor, but why rush into it? Enjoy the drive!

So, yeah, it was bitter, bitter cold when Pete and I arrived at the hangar hoping to perform the most procrastinated task yet: the replacement of the brake fluid lost from the system as a result of removing the landing gear and taking that opportunity to also re-route a brake line that was poorly positioned and was rubbing against a neighboring line is a most disconcertingly intimate way. No good was ever going to come from that!

I had been dreading the re-bleeding of the brakes based mostly on the frustrating experience we had with it the first time. But, as with many (but by no means all!) of these things, it went far more easily the second time around.  For the most part I was pretty well thermally protected by my Walmartts and glittens, but exposed fingers and anything else than came into contact with cold-soaked tools and airframe strenuously objected to the frigid conditions.

The brake bleeding went so well that we had a little spare time before our core temperatures reached the level of mild hypothermia, so we took the opportunity to do few more of the ever-dwindling list of to-do items. Probably the most gratifying was the final riveting job: the installation of the data plate.

To top it all off, we put the wings back on. 

I have a few more placard decals to put on in order to satisfy the labeling requirements of the FAA, and then it is simply a matter of paperwork.

SB 12-11-09, Part 2

It took awhile, but eventually the impediments to continuing work on the service bulletin all melted away.

Christmas is over and done with, and departing with it are the stress and distractions incumbent in maintaining at least a patina of the societal demands of perpetual good cheer. I can easily and honestly maintain the Spirit of Christmas Past, it's the non-stop, full immersion Spirit of Christmas Present, which as we all know now runs from late September to sometime in early January, that taxes my patience. Fortunately my lad Cabot is easily pressed into service as my proxy.

I'm also completely over the shame and personal disappointment arising from my muddle-headed mis-drilling of a 3/8" hole as a 3/4" hole. Having now used the holes, I have to say it: had I not accidentally made these holes 3/4", I would have done it deliberately. Look how well they work! A 3/8" hole would have been far more difficult to use.

And as we can see in the upper right hand corner of this picture, perfectly sized caps were available to close the holes up when they're not in use. Oh, and the 6" long 1/4" bit was perfect for drilling through the center section. Any other bit would have been either painfully too short or too long.

It turned out that it was possible to use the countersink bit without removing it from its cage, but I wasn't really keen on having to hold it still while using it.

The replacement of the landing gear itself was a three hour ordeal performed with the able assistance of Pete and his son Warthog. It wasn't a great deal of fun. In fact, it was quite cold. I'd say the job took a good hour longer than it should have simply because our fingers were numb from the cold!

The brake lines still need to be reattached and bled, which is another job I'm not really looking forward to. But once that's done, I just have some paperwork to do in preparation for my inspection by the Feds.

"What's it like?"

You get a lot of questions from people that find out that you are building an airplane.

Some become routine.

Some test your ability to suppress an eye roll.

Examples of those are "When will it be done?" and "A real airplane? And you're going to actually fly in it??"

After awhile you build up a library of ready answers for the most common ones, along with the ability to spit out a wordy non-answer when the real answer would require too much time and effort. You know, much like a politician.

The hardest question of all, though, is, "What's it like? What is building an airplane like?"

It's hard to answer because there is no simple, concise response that can truly convey what the experience is like. Most people have never tackled a project that requires the level of commitment, persistence, tenacity, frustration, elation, perspiration, dedication, and time that comes with the job of building an airplane.  There are parallels that can help people to understand, of course, but few of those example projects eventually  result in a day when you are going to trust your very life to the end product.  It is that aspect, I believe, that erects an insurmountable communication barrier between those that have and those that haven't.  It is also why one of the more routine questions, albeit almost always a rhetorical one, is "Are you crazy??"

In some ways, the answer is "Yes, I  must be."

It is important to understand that building an airplane is not something you do. It becomes, to a very large degree, what you are. A project of this magnitude has an effect on your life. At work, at home, in the middle of the night when an anxiety attack resulting from an issue with the plane is keeping you awake - the project is always somewhere in your mind. A bad day at work will often result in a bad day working on the airplane. A bad day working on the airplane can easily cause a bad day at home. It becomes intertwined in personal relationships.

That goes both ways, though. The first time you step back from having placed the final rivet in something that actually looks like part of an airplane. The first time you move the control stick and parts of the airplane move in response. The first time you sit in it. The day you start the engine for the first time. The sense of accomplishment and the pride of having actually created a part of something that hundreds, thousands of previous generations could only dream about - people will be questioning what kind of wonderful drugs you're on. And with each of those moments comes the understanding, the visceral knowledge that someday, someday, it will fly! Which is, of course, tempered by the immutable fact that you will be in it.

That little demon is always in the back of your head, gnawing away at your elation.

That little demon has its purpose, though. There will be days of abject frustration. There will be parts of the project that are just plain hard. There will be temptation. "Screw it, this is good enough," the temptress will say. "Let's just get on to the next thing."  The little demon will have none of that. These are the times when that little bastard is going to insist that you take a step back, maybe even take some time off, and come back refreshed and ready to do that task right. He's there to remind you that someday you will be betting your life on the quality of this work. And if that doesn't do the trick, he is not above reminding you that the airplane has a second seat which will someday be occupied by an innocent whose life is riding on the same bet.

Is that an emotional burden that can be hard to carry? Hell yes it is! It is part of the reason that  building an airplane is not something you do, it is something you live. It is why even simple mistakes will plague your waking thoughts and disturb your sleep for days. And you will make mistakes. There are few things you can do in life that can be as humbling as a project like this. You will be furious with yourself. You will be astounded to learn how fallible you are. You will question whether you should even be doing this. "How could I have missed that?" will be a question you ask yourself every bit as often as a curious person will ask "When will it be done?"

You needn't be alone, though. At least in the case of my RV-12, there are other people that have gone before and are willing to share helpful tips and pieces of advice. Not all of it will be useful; you need to be the final judge as to whether you want to follow anyone else's lead. You will have visitors as you work. You may even be lucky enough to pick up ready and willing helpers along the way. Chances are that you will be blessed with new, lasting friendships.

Sure, there will be a few know-it-alls that think their way of doing any particular thing is the only way, but that's endemic to the breed of person that has the self-confidence to tackle a project of this magnitude. There are points of contention that actually bring out evangelistic fervor in some people. Emotions can run high.  It's not always easy to set that kind of thing aside and get back to focusing on your own work, but as with any of the plenitudinous other frustrations, it's best to just step back for a few days and get settled down before doing any work on the plane.

That is, in fact, one of the more important lessons to learn. There are days when you aren't working on the airplane because you want to, you're working on it out of some sense of obligation or pressure from external influences. It is at these times when you are more likely to make mistakes. Your mind isn't fully engaged. You can read directions that clearly state the need to drill a 3/8" hole and proceed to blithely drill a 3/4" hole. You will then spend a few days beating yourself up over it.

The lesson to be learned is to know when to not work on the plane.

An adjunct to that lesson is to know when not to put pressure on yourself. Unless there is a good reason to do so, deadlines for completion are best avoided.  Delays are inevitable. Parts may need to be replaced. Tools may need to be acquired. Midstream changes can come flying in from the factory at any time, often requiring the re-work of something you thought was finished and done. Knowing at an intellectual level that these things can and do happen helps, but it cannot prevent the immense frustration that comes from an unexpected delay. It's just one more thing to deal with.

So in light of all that emotion and complexity, what's my answer when someone asks me what it's like to build an airplane? How do I condense all of this down into an easy answer that at least partially conveys the depth and subtlety of it all?

Like this:

"It's a journey of self-discovery."
 

Extra Innings

This is my second try at this post, the first having been deleted because it was just a bit too frank. A bit raw, if you will.

I find myself in a strange and unfamiliar place all of a sudden. I'm sure this is something that will pass, and hopefully quickly. The thing is that I think I've hit a wall.  At this moment, I really just want this project to be done.

Maybe it's this service bulletin - it's a lot like getting to the bottom of the ninth and finding that the game is going into extra innings.  I'm just not in the mood for it and it is having a bad effect on my thinking. I just can't seem to get out of my own way. It feels like it has been one screw-up after another. It's like waking up to find you suddenly have two left hands, and you're right-handed.

It's odd to be hitting me this late in the game. I got past the longerons. The canopy is done.  In the grand scheme of the last three years, this work is relatively simple. I don't understand why it's suddenly all so frustrating. I don't understand where this mental haze has come from. Seriously, drilling 3/4" holes instead of 3/8"?? Who does that??? I ordered a countersink bit that's too small for the job. I ordered it in the first place so I wouldn't ruin one of the countersink bits that I've been using all along by having to chuck it into the drill press, completely forgetting that the cage itself is chucked into a drill all the damn time!! 

My brain has called it quits.

And to do it all so.... publicly!! As much as I enjoy the writing, this blog can at times cause quite a bit of additional stress. I decided from day one that I would share it all, warts included.  There are days, though....  I'm this close to just shutting it down.

Maybe it has nothing to do with the current work. In fact, I hope it doesn't. Maybe it's just carryover from the stress from the paying gig which is worthy of another blog in its own right. A lot going on there that has me well out of my comfort zone. At this point, should the Mayans prove to be correct, I'm not sure it wouldn't be an improvement.

I guess it doesn't matter where this is coming from - it's here, it's now, and it needs to be dealt with.  Writing about it here is a start - the act of putting things in words on a page has a way of getting the circling ideas out of my head. It's therapy, in a way.  Confession: it's good for the soul.

I'm going to just push this all aside and get through the last couple of days in the mines before my annual 13 day sabbatical.  Things will look better when I only have one thing to deal with. I'm sure of it.

Thank you for your patience.

SB 12-11-09, Part 1

The parts required to complete the landing gear fix finally arrived, and with them came unseasonably warm December weather. It couldn't have worked out any better! With a comfortable 50+ degrees on tap for the weekend, Pete and I decided to get as much done as possible before the inevitable cold weather returns.

I started out by marking the locations where I would be drilling 3/8" holes in the belly of the plane. These holes will provide access to four of the bolts that hold the landing gears legs onto the airplane. This access will allow for periodic inspection and re-tightening of the bolts as required.

As usual, I very precisely located the spots for the holes, knowing full well that the actually drilling of the holes will result in very imprecisely located openings. It won't matter much; there will be plenty of wiggle room for the socket extension.

With a few years of bitter experience telling me that drilling with the step bit generates lots of shavings and that gravity will ensure that mot of them fall into my eyes, I made sure to wear my safety glasses. As is typical when I do this, they only managed to block approximately ninety percent of the falling detritus. The rest will float out in tears over the next few nights.

There were eight (four per side) difficult to get at rivets to be removed down inside the center section. The only way to get at them was to climb into the plane, something I really don't like doing when it's supported only by sawhorses.

A big part of the problem that caused the release of the factory service bulletin was wrinkled side skin as a result of loose gear legs wobbling around. Unsurprisingly, a big part of the fix for the problem is hefty skin doublers. All of those circles are new holes that need to be drilled into the side skins. These doublers will improve the strength of the side skins by at least an order of magnitude, causing me to wonder just how weak this part of the design was in the first place.

Having two drills handy made it easy to get both sides done concurrently.

Also tagged for increased robustitude were the steel "wear plates" that formed half of the metal sandwich that held the gear legs in place. Looking at the replacement parts as compared to the original parts again made me wonder just how weak the original design was. The new parts are in the back - just look at how much thicker they are than the original parts!

As I was drilling old blind rivets out of the side of the fuselage, I couldn't help wondering what we would do to get the old rivet shop heads out of the sealed area of the fuselage. Van's suggestion was to use a 3/4" diameter piece of rubber hose attached to a shop-vac to suck the little buttons out of the enclosed areas. That worked poorly. In fact, I don't think I was able to remove a single piece of rivet. It was impossible to see inside the area in order to find the little bits. Leaving the operation to random chance by waving the tube blindly around inside the airplane didn't seem like a very good idea.

Pete came up with a better idea. He covered a finger in masking tape with the sticky side facing out and just poked around in there getting rivet bits to stick to the tape. He later improved on that plan by shaking the airplane around a little bit to encourage the rivet droppings to roll to the lower bulkhead where he could collect them in bunches.

Meanwhile, I riveted in some new, thicker side stiffeners. Access to the rivets was somewhat inconvenient.

This rivet location was particularly bothersome. The only way to reach that rivet with the puller was to follow Van's directive to tap the big brass spar bushing to push it back out of the hole in the spar. It's in there quite tightly, so I am not convinced that "tap" is the appropriate word. It took pounding to get it to move. I wasn't keen on the idea of pounding soft brass with a steel sledge hammer, though.

What we ended up doing for both moving the bushing out and pushing it back in was to use a small chunk of 2x4 to provide a soft(er) surface against the face of the bushing and a length of wood to use to pound on with the sledge. This work very, very well.  Below is a picture of the setup for pushing the bushing back in.

Even with the bushing out of the way, the rivet puller was at a slight angle when trying to pull the rivet. These are not the normal blind rivets used in the rest of the plane - these are special rivets known as "cherry rivets." They are much stronger than the regular rivets used just about everywhere else on the RV-12, and something about that makes them impossible to pull at an angle without the mandrel immediately breaking off. When this happened, it left the remainder of the rivet in the hole with no way to complete the pulling. I was at a loss as to what to do about this, but after thinking it over, I decided to treat is as if it was a solid rivet. In other words, I just drove it in with a rivet gun and a bucking bar. The little brass thingy is a little extension we made out of brass plumbing parts from the hardware store. The cherry rivet actually isn't a solid rivet, so I used very light sir pressure and only a few taps from the rivet gun to finish its set.  Looking at the shop head once I had finished tapping it, it was impossible to tell that it had been done any differently than they ones I set with the rivet puller.

NOTE: There are those that believe that it makes a difference from which direction the shop head of the rivet is formed, so use your own discretion.  I can't see what possible difference it could make and I am perfectly comfortable with my decision, especially when considering the relative weakness of Van's original design that used a normal LP4-3 rivet in this exact same hole, but seriously, do what you think is right. I'm just here to share my experiences, not to tell you how to build your airplane. It is becoming abundantly clear to me why Dan Checkoway deleted his entire RV-7 build blog, though.

Once that was done, it was a simple matter to rivet in the side doublers.  Well, it would have been simple if the cherry rivets didn't display a propensity to jam up the Harbor Freight pneumatic puller. The first time it happened, I took the puller over to the work bench to disassemble it in order to figure out why it had jammed.  That in itself wouldn't have been a problem, but I have somehow developed the bad habit of absent-mindedly carrying stuff with me and leaving it sit somewhere else, only to return to the work site to find something mysteriously missing. In this case it was the small plastic bag of cherry rivets. Nowhere to be seen. And quite the mystery it was, too. I retraced my steps, but they were nowhere to be found.

Having a far superior institutional memory than I do, Pete remembered the lesson that we learned after finding a dropped part in the most unlikely location (it had fallen into the open bottom of one of the control sticks), that lesson being that odds are that if we can't find something easily, it has found its way into the very last place you would expect it.

And so it was. We found the bag of rivets.

As usual, the actual riveting was really a bit of an anti-climatic event once we figured out how to easily un-jam the rivet puller.

The next steps involve the preparation of the new mounting plates. Unfortunately, one of the plates requires countersinking with a countersink bit that I don't own. We were unable to find one at any of the local hardware stores, so I had to order one on the internet. Here it is, for anyone that may need one:

Edit: I was just planning to use one of the standard 100 deg 1/2" piloted bits in the spindle portion of a disassembled countersink cage.

The bit I ordered is too narrow. I'm going to try the suggestion above if the bits I happen to have on hand are wide enough.

There are also four 1/4" holes to be drilled all the way down through the center section and those big mounting plates. As long as I was ordering the countersink, I ordered a nice 1/4" bit.

1/4" High Speed Steel Aircraft Extension Drill Bit - 6"

We're on hold until those arrive.  Hopefully they will end up being the right tools for the job.

"For awhile, they were asking how long it took to build."

"Now they're back to asking when it will be done."

One of the nice things about working in the hangar on a nice Saturday morning is the steady stream of visitors that are either stopping by for an update or those intrigued by the sight of an airplane being built. Both groups have been known to ask both of the questions above, but the latter group, the first-time visitors, had recently starting to ask only the latter question.

Not anymore.

The reason for that has to do with the number of things that have been undone as I prepare to receive the new landing gear reinforcement parts from Van's. As usual, that is a somewhat open-ended commitment from Van's - they do things at their own pace and aren't always particularly precise when it comes to telling us when to expect things. It's a lot like having the cable service department tell you on Monday morning that the repairman will be there sometime between 9:00 am and..... Thursday.

"They'll be there when they get there," if I may paraphrase.

No sense lying idle while waiting, though. The landing gear legs are off already, as you may recall, so this weekend I did the next couple of steps. Van's seems to have decided to address all issues with the landing gear installation big and small, and one of the smaller ones was a slight interference between the two big landing gear attachment brackets and the large end of a few rivets. Rather than have us remove the rivets (which wouldn't be easy or smart), Van's has us grind the edges off of the steel brackets.

That may be smart, but it's not necessarily easy. It involves the grinding wheel - one of my least favorite power tools. Parts being ground (grinded?) get very hot, there are a lot of sparks flying around, and I'm always a little nervous that something is going to break and get flung off of the wheel in the general direction of my head. And I don't need any more damage to my head, thank you very much!

As predicted, the bracket got pretty hot. I could feel it getting too hot to handle even with gloves on, so I had to set it down to let it cool off between grinding sessions. Luckily it was pretty chilly in the hangar and it cooled off relatively quickly. I filled the time by drilling out the rivets that will be replaced when the new doubler than Van's is sending to beef up that part of the side skin arrives. The gloves came in handy for that job too, but to protect them from the cold rather than the heat.

I made a special tool for drilling out the rivets based on a tool I had seen before. It was as simple as sacrificing a $5 Harbor "THE Place for Fine Sacrificial Tools and Furry Mammals"  Freight center punch by grinding down its point so that it would fit into the mandrel hole of an LP4-3 rivet.

Usually it only takes a punch or two to knock the remaining mandrel out.  Once that's done, slow drilling with a #30 bit will take the cap of the rivet off. Once that's done, another punch or two will knock the rest of the rivet out. In some cases a light spin of the drill is needed to add encouragement. Mostly, though, it's pretty easy.

Right up until it's not. In this case, the tab that the rivet went through just pushed away from the punch.

I tried grabbing the tab with a cleco clamp.

That still wasn't enough. I added the blade of a small screwdriver to the mix. That held the tab firmly enough to let the center punch do its thing.

There! One side done!

Between bouncing from grinding to rivet removing and back again, I mostly finished up the preparation for installation of the Service Bulletin parts.  The foresight and extra effort that went into getting ready for the parts before they get hear will surely be paid off with a nice, lengthy wait for the parts to get here. 

 Because that's the way these things go.