Monday, August 29, 2011

It's touch and go

I can't help feeling that this canopy is going to end up being a very slow motion train wreck. While part of me is sure that it will all work out, the part of me that writes checks to replace munged up parts is convinced that I am only one step away from ruining a very expensive piece of plexiglass.

On the plus side, I've won my last two Words with Friends games, so there is that. The last one was touch and go to the very end. I was behind by a dozen or so points with only the letters in my pile remaining to play. I scored fifteen points with a well-placed US, with the 'S' combining with QUADS to produce SQUADS. Up by three, but convinced that I would be overtaken in the stretch to lose by a nose. And nothing left in my quiver but a single, solitary N. Sure enough, my opponent's next play had me down by eight. But there it was, sitting there all ripe and ready for plucking: SEW. With the N to make it SEWN, I took a one point lead and ended the game!

Okay, back to the canopy. As we left the saga, the canopy was in place on the frame but needed to be trimmed for length. It was too long and the excess length was keeping the back edge from sitting flush against the rear window. Taking a hint from Don, soprano vocalist and 12 string lead guitar of The Jackson Two, I braved the maddening crowds at the Harbor Freight (Home of Low Performance Air Tools) sidewalk sale to pick up an air-driven mini belt sander. It's a cute little thing and offers nimble control and a very comfortable (read: "slow") cutting pace.

I shaved off just enough to get the canopy to sit flush. More will have to be removed later.

With the canopy back in place, we tried to mark the tangent line on the front cross bar to find the correct place to drill the rivet holes that the front of the canopy will attach to. The idea (according the the folks at Van's) is to press the canopy against a loosely attached piece of masking tape; they theorize that this will somehow show the correct line. Well, not so much. Admittedly, I was using tape that I bought at Harbor Freight, the Home of Non-sticking Except Where You Don't Want It To tape. Figuring that the tape could use a little help, I resorted to using some blue chalk rubbed on a piece of tape inside the canopy.

A great idea (that I stole from a web forum posting somewhere), and it would have worked, too, except for the inconvenient fact that the tape was also blue.

Still, enough of the chalk was discernible (if the light was just right, and if I viewed it at exactly the correct angle, and if the chicken that I sacrificed at the little altar that I keep in a deep, dark corner of the hangar actually was a virgin) to provide a just-good-enough path to trace with a Sharpie(tm).

With the line to follow, it was a simple matter to drill the #40 pilot holes.

The canopy still didn't fit precisely right, though, but I figured that I had pushed my luck far enough for one day.

I had considered going out for some more work on it again tonight but the weather was far too good. Rather than stress out about the canopy, I decided instead to go fly the RV-6 for a little while. My landings have been pretty shoddy so I decided that a few touch and goes would do me good. We had almost no wind, startlingly clear air, and moderate temperatures to go with the relatively high pressure. In other words, perfect weather for the airplane and pilot both to excel. The only fly in the ointment was the hot air balloon (aka 'hazard to aerial navigation') that insisted on parking just off the end of the runway. No problem for Papa, though: with an empty pattern, we could scream down the runway at ten feet of altitude until we reached 120 mph on the speedometer. A brisk turning pull-up before the end of the runway had us reaching pattern altitude at midfield downwind just as we rolled out of the 180 degree turn. A nice landing right on the numbers left us most of the runway to just do it again, and again, and again, and again.

Five touch and goes in .22 on the tach: that's pretty economical flying!

Sunday, August 28, 2011

A game of fractions

As our April in August continues apace, I vacillate between a visceral, slow-burning anger that I am still mowing the vast grounds of my palatial estate and the joy that I find in having some decent flying weather for what seems like the first time this year. Tempering the desire to go flying at whim, however, is the extraordinary cost of gas this year. In a nutshell, I am digging deep to find even the remotest excuse to fly in order to avoid being burdened by the guilt arising from the conspicuous consumption of carbon-based combustibles coincident to clearly casual usage.

Fortunately, I was able to scare up the semblance of a mission yesterday. Some of my long-time readers will remember that one of the project ideas that I kicked around during those empty, meaningless years before I embarked on the current RV-12 journey was to find an older RV-4 that would make a good platform for updating/upgrading. A soundly built, minimally equipped RV-4 with a medium time engine is selling in the mid to upper $30s these days, so the acquisition cost is reasonable. I would never undertake to actually build an RV-4 due to the order of magnitude more difficult nature of the build process as compared to the RV-12 (which is quite challenging enough, as we've often seen), but I would enjoy re-wiring and updating the electronics/avionics quite a bit. That's fun work!

Through the miracle of the internet, I learned of a guy that is doing exactly this, and he lives right here in town. I begged a visit to his work site in order to get a feel for the nature of the work involved.

Cadillac Pete and I flew up to Delaware Co. (KDLZ) airport early yesterday morning. As you will be able to see from the following photos, the job is nearly (and neatly!) done:

While the wiring and avionics work was interesting, I found the air-locs used to replace the frustrating cowl hinge pins absolutely fascinating. This is something that I wish I had done on the RV-6 and will almost certainly do on the RV-12 at some point.

Back at the Schmetterling shop, Pete and I laid the canopy in place for its first trial fit.

We immediately found a problem. The pre-drilled hole for the canopy latch handle didn't line up. This caused a notable degree of angst in the sensitive belly of your's truly - the idea of elongating that hole simply did not appeal to me for any number of reasons, and I frankly couldn't fathom how Van's could have misplaced the location of that hole so egregiously.

"No Panic" Pete, provider of prescriptive and prophylactic advice pertinent to any particular problem providentially perceived the providence of the problem: when I had moved the wooden spacer blocks and the clamps holding them to the bottom of the roll bar, I had allowed the blocks to settle to the lower portion of the roll bar, thus allowing upper portion of the roll bar to angle too close to the rear window. I moved the wooden spacers such that they provided support for the entire back edge of the roll bar.

Problem solved! As I said at the time, "I wish they could all be California girls, but I'll settle for all problems being solved this easily."

Working under the assumption that having the pivot tube for the canopy latch handle now centered into the pre-drilled hole in the canopy strongly indicated (I hesitate to say "proved" - I'm done with alliterative 'P' words) that we could move on to performing (drat!) the measurements provided (argh!) in the plans (I give up). One such measurement is the requirement for a 1/8" gap between the lower edges of the canopy sides and the edge of the canopy frame. I was at a loss as to how we could ensure that gap, but a search of the scrap bin came up with a 9" length of 1/8" angle aluminum. I cut it into 12 little segments to use as spacers.

We started taping down the sides of the canopy with the spacers in place.

Then we ran into a problem. The 1/8" gap on the left side of the canopy was mostly uniform for the entire length of the canopy, but the ride side had an area where the gap was far larger than 1/8". We tracked this asymmetry down to a difference in the two sides of the canopy: one had a 14" length from the back of the canopy to the spot where the edge changes direction, while the other had only a 13 3/4" length.

That difference throws everything out of whack. Looking ahead in the plans, it appears that the gap will be covered by a skirt piece made of aluminum, but I'm reluctant to accept this discrepancy as allowable without doing a little bit of research first. It's these little fractions of an inch that end up being bigger problems further down the road.

As it turns out, a closer reading of the plans shows that 1/8" is the nominal gap, but up to 1/4" is allowable. No harm, no foul as they say. We are clear to proceed.

Sunday, August 21, 2011

Swimming on dry land

I had to mow my lush, vibrant green lawn yesterday. That wouldn't be a startling fact if this was May or June, but in late August I'm used to a dry, burnt umber lawn as the grass takes a late Summer siesta. Not this year, though. We're something like seven inches over the normal year-to-date precipitation level and the result of this is a lawn that would be more appropriate to the traditionally wetter months earlier in the year.

This surfeit of moisture has also resulted in the kind of humidity that one would expect from a Brazilian rain forest. It's so muggy that you feel like you could swim though the heavy, cloying air. And as we all know, it's not the heat that makes late summer life unpleasant, it's the humidity. I thought I'd get an early start on the day and beat the worst of it and I imagine that I did just that, but it was still 80 over 80 (degrees over relative humidity) by 10:00 in the morning.

I only intended to work for a short while anyway since I was planning on making my "zip code famous" ("World Famous" being as unprovable a claim as it is ubiquitous, to the degree of being a cliché) pot roast. The secret to my pot roast is in the liquid I use in the pressure cooker to cook the meat: Sam's Club cocktail sauce mixed with beef broth. The pressure cooker ensures a fall-apart tenderness, and the cocktail sauce infuses a subtle tang. Magnifique!

It was all o be one-man work on the plane (or so I thought), so I didn't bother to solicit any help from Pete. I figured I was just going to match drill the holes from the rear window into the roll bar and I could do that all by my lonesome. That went so easily, though, that I was done in no time.

There are only a couple of steps remaining before placing the canopy onto the frame for its first fitting and I will definitely need help with that, so since I was ahead of my fairly loose schedule I thought I'd go ahead and get them out of the way. All that remains to be done is to fit a few pieces of thin angle aluminium onto the canopy frame to provide something for the lower edge of the canopy to be screwed into.

I decided that I didn't want to do that without first replacing the spacing washers that we had installed to keep the front of the canopy from interfering with the forward fuselage cover. That turned out to be a little tricky to do alone. Every time I've done it before, I've had Pete there to hold the canopy frame up while I add the washers. Without his help, I had to find another way to secure the frame in the up position. It turned out to be as easy as tying a piece of string around the forward hoop and the upper engine mount.

Easy, but not frustration free. If you look closely at the roll of string, you will see that some of it has been re-wrapped on the spool. That's because I accidentally knocked the spool off of the firewall shelf and watched helplessly as it ran down the slope of the hangar floor and out into the taxiway.

How very amusing.

Pete usually holds the frame out away from the side of the fuselage while I get the washers in place. Without him there to do that, I had to dip into my collection of Harbor Fright surgical instruments (Harbor Freight: The Home of non-Sterile Surgical Tools and 4 Pound Hunter Orange Anesthetic Bludgeons) to find something with which to place the washers. This little gizmo did a great job:

Preparations out of the way, it was time to bend metal. The pieces of angle have to be fluted to introduce a curve into them that will match the radius of the canopy frame. They actually have to match the inner radius, but here you can see the matching outer radius:

It's been awhile since I've had to flute parts, but it turns out to be just like riding a bike: if you screw it up, you're going to be really in a world of hurt. I didn't, though. They turned out quite well.

From there it's clamp, match drill, and cleco.

I only got the right side done before I was too sweaty and miserable to continue, but the left side should go pretty quickly next time I get out there.

Saturday, August 20, 2011


There are some weeks that I leave with the same sense of relief that I feel every Spring when I can finally consider Winter to be well and truly done. This has been one of those weeks. Between an invasive and extraordinarily undignified medical procedure (which I cannot even remember much of thanks to modern IV-delivered pharmaceuticals) and the angst that surrounded my involvement in causing a million dollar hit to the annual bottom line at the paying job, the stress brought on from the difficulty encountered with an obstinate and recalcitrant part on the RV-12 was certainly not welcome. That said, I think stepping away from the problem for a couple of days was the right thing to do.

You may recall that the problem I'm talking about centered around the, well, center of the forward hoop on the canopy frame. The problem was that the hoop was not straight and it was therefore impossible to adjust its position to create a uniform 7/16" gap from the hoop to the instrument panel. After thinking about it for a day or two, by which I mean losing sleep over it, my theoretical solution was to remove the canopy frame and support the center of the hoop on an extended jack stand, the idea being that I would then be able to exert pressure on the outer halves of the hoop, thereby straightening it.

That worked magnificently. I really couldn't have done it without Pete, though. Without him standing there threatening to whack my wrists with that big metal straight edge, I wouldn't have had the nerve to really bear down on the hoop with the force required.

It turns out that brute force was to be the rule of the day. Even with the hoop straightened, it still wasn't at the requisite 7/16" gap from the panel. The rectification of that issue required the repeated application of blows from the mallet that I use for deer hunting. Well, I don't really, but how else to explain the vibrant orange color?? This is the same mallet that I bought from Harbor Freight (The Home of Wildly Inhumane Hunting Weaponry) when I was struggling with the longerons last year. I have nicknamed it 'Ole Last Resort'.

After a few dozen sharp whacks, it appeared that the hoop had actually moved closer to the panel, but I was becoming increasingly concerned that 'Ole Last Resort' was soon going to earn the new sobriquet 'Ole Aww Crap' if I kept pounding away at the hoop. I made a decision and shared it with Pete:

"I'm going to hit this thing fifteen more times and call it quits."

He replied, "Fifteen? That's a somewhat capricious number, is it not?"

Yeah, he really talks like that. It had only been a few minutes since I had shared an anecdote about having recently seen a horizon-to-horizon double rainbow, with his ensuing question being "whether I had seen Mobius' Dark Band."

I may be remembering it incorrectly since a later Google session on the topic of double rainbows and dark bands retrieves only references to "Alexander's Dark Band", but in either case I was dumbstruck, having never heard of either of them. After a stunned pause, my only retort was a flaccid "I don't know why I even talk to you."

In any event, there was nothing capricious at all about my selection of the number 15. That number is, after all, my lucky number.

"What," you ask, "makes 15 such a lucky number?" Well, Pete asked that too. You see, many, many years ago when I was no more than eight or nine years old, I was at a church carnival kind of thing. There was a woman walking around who would tell you your fortune for a mere nickle. Upon receipt of my nickle, I was allowed to pull my fortune from a pile of paper slips that I now know as the innards of fortune cookies. For the princely sum of five cents, I learned that my lucky number is fifteen. It wasn't much of a fortune, really, but it was the only time I ever learned any Latin from the Catholic church. Too bad it had to be caveat emptor.

So you see, there was nothing capricious about it at all. It was fated, lo those many years ago. And, since fifteen strokes on each side left the hoop exactly where it needed to be, it was five cents ($.2248 when adjusted to 2010 dollars using the CPI metric) well spent.

Having the hoop problem solved was a pretty big deal, and it relieved some of the frustration we had endured in getting the turtle deck skins and back window clecoed into place. The back window needs to be installed in order to correctly position the canopy. I've put off installing the turtle deck skins for a long time because they don't fit very well and it's a pretty big undertaking to get them on. But that was nothing to the fun of trying to get the window in place. We got it done, though.

It's just too bad that one of the fundamental truths about building an airplane is that what has been done, is soon to be undone. After match drilling the screw holes in the roll bar, all of that stuff gets removed.

Thursday, August 18, 2011

Some thought required

It seems like I've been doing a lot more thinking lately. Deep thought is pretty much the norm at the paying job, but I like to spend my off-work hours avoiding cerebral activity as much as possible. This week, though, I've been faced with a virtual cordilleran of mental hurdles.

First came a new internet game that I've been playing. It's called Words with Friends, but it's really an almost direct rip-off of Scrabble. The big differences are that it's far more asynchronous and the other player can be anywhere on the planet. Given that my opponent and I both have other responsibilities, it is often the case that our moves are separated by hours.

It's really quite fun, but I'm getting pretty frustrated. I spend 15 or 20 minutes trying to come up with pithy, insightful words but usually end up with things like 'huff', 'tern', 'geek', 'hog', and 'opine'. Some of those are pretty clever, but mostly I end up sound like a first grade reading primer. My opponent, on the other hand, was clearly a Scrabble prodigy; he plays for the most ruthless score he can manage. 'Opine', a word I was inordinately proud of, scored nine points. My opponent plops down "lat" (that's a word???) but has it sitting right next to the 'ote' of one of my words, 'quote'. This apparently also spells such useful words as 'lo' and 'at' and scores an astonishing 68 points.

I'm clearly going to have to up my game.

Anxious to get away from the ignominious defeat that I will inevitably suffer in the word game, I decided to give Pete a call and see if he wanted to do some more work on the canopy frame. It seemed easy enough, although we would be working in a new medium: cardboard.

All we had to do was cut out some cardboard to put a 1/8" gap between the canopy frame and the fuselage sides. Easy enough.

It turned out pretty well, even though I was using some freebie scissors that I got at Harbor Freight, the Home of Plastic-Based Scissors and Low-Lumen Flashlights.

It all went downhill when the next step directed us to ensure a 7/16" gap between the frame hoop and the instrument panel. The trouble arose when we found that the hoop wasn't consistently straight. It seems to have a bend in it at the center weld that causes the outer parts of the hoop to be further away from the panel than the center part. Try as we might, we couldn't come up with a way to bend the hoop straight.

Having thought about it for awhile, I now think we can do it by removing the frame and placing the center weld area on the top cradle of an extended jack stand. That will provide support at the center of the hoop while we press on the other portions.

It means undoing this fancy clamping work that we did, though.

When I got home from the paying job today, I had an email from a guy asking about the RV-6. I normally wouldn't share it here, but it was easily the most interesting and thought-provoking inquiry that I've received:
Dave, good afternoon.

I'm constantly browsing through barnstormers and for a RV-6 that catches my eye. I keep coming back to yours yet it lacks the 360 C/S that I've been holding out for. I'm hoping to use it for local gentleman's aerobatics and some x-country legs on occasion. I don't need the most efficient cruising bird out there so I've been leaning towards acceleration performance.

I love the old warbird look you have going on and the instrument configuration. My only hold back seems to be what's up front. What has been you experience with it compared to some other RV's you've been in? I know the benefits of the FP prop are simplicity and cost but what am I realistically giving up performance wise?

Also, do you have any adjustments to the oil system for inverted flight or vertical maneuvers? I've read where some lean the oil resevior 15 degrees back so it has constant flow while going vertical. I'm not looking for a G monster airplane, but just something I know I can safely have fun in with two people on board. I look forward to hearing back.

I found this interesting because I myself have wrestled with questions like these. Should I add IFR capability? Should I get a bigger engine? Is it really worth the cost? I spent some time on my reply:
I'm going to have to set aside the fact that I'm trying to sell an airplane
put on my consultant's hat for a few minutes.

I've always said that when it comes to airplanes, you need at least two but
no more than five to do everything that you want to do. Since few of us can
afford a Harrison Ford lifestyle, we have to make do with one. Everything
about the design of an airplane is a compromise and it is rare to find a
design that does everything that you want, but the RVs come closer than
anything else I know about. Even with the RVs, though, there are compromises
between the different models. In fact, given the level of builder
customization that goes on, there are compromises to be made within each

If you had said that your primary purpose was cross country or day trips, I
would say that any of the RVs would do, but an RV-6 or RV-7 would be
preferred for the side-by-side seating, even when flying alone. And unless
you live in a high altitude area, I would have said that your best choice is
an O-320 with a fixed pitch prop. At higher elevations you would want the
better takeoff efficiency of the constant speed prop, so the trade off in
increased weight and complexity would be worth it. At really high altitudes
you would want the even better climb performance of the O-360. But down
below 4,000' or so, I'd say stick with the lower weight and lower fuel burn
of the O-320 and a fixed prop.

When you start talking about aerobatics (or formation flight, for that
matter) as taking primacy over travel, I would recommend an RV-4 or RV-8.
When it comes to aerobatics or formation work, it is much better to be
sitting on the centerline. With the RV-4, you'd be fine with the O-320, but
for an RV-8 I'd look for an O-360. Depending on the type of aerobatics you
want to do, the constant speed prop is optional. I just pull back the
throttle at the top of the loop to keep from overspeeding the engine. Since
everything I do ends up at the same altitude and energy level as when I
started, I don't need the extra climb performance from the bigger engine.

For formation flying the CS prop it's pretty much mandatory because of the
more rapid acceleration and decelleration it provides.

This is not to say that you can't to aerobatics in an RV-6 or RV-7. You can,
and I do. Without inverted oil, I limit myself to positive G maneuvers only.
I don't figure I'm giving anything up - I've tried negative Gs and I don't
like them. At all. So if by "gentleman's aerobatics" you're talking about
some loops and rolls now and then, just about any RV will do. If you're
talking about being able to fly inverted for even a few seconds, you need an
external oil tank and plumbing for inverted flight. Just be aware that the
queasiness factor is increased a lot by sitting off center.

Now, back to my airplane. I have never missed the cost, complexity, and
weight of either the O-360 or the constant speed prop. I have on occasion
missed the performance aspects of them, though. I tried my hand at formation
flying and fortunately didn't develop a taste for it since it is really much
harder with the FP prop. I've also had hot summer days when I would have
appreciated the extra 30 hp from an O-360 just for getting off the runway,
or when trying to climb above 10,000'. That 30 hp doesn't buy you much in
cruise speed, but it sure helps in climb performance. That said, when flying
at gross weight on a hot day I still get around 500-600fpm at sea level.
Light on fuel and with just me in it, I often see 1,500 fpm. The RV is such
that there is a definite performance difference as weight and weather
change. I think the gross weight takeoff and climb performance is probably
where you would see the most gain from the bigger engine and more efficient
prop. Hard to say if it's worth the cost, though. It wasn't to me when I was
asking myself these very same questions, but then again I'm building an LSA
so I'm obviously more focused on lower costs and simplicity.

Regarding vertical flight, my vertical flight has been limited to climbing
into a loop, but I know guys that don't have inverted fuel/oil systems that
regularly do hammerhead stalls. I've personally never had the guts to try

I can provide you with a couple of resources if you're still interested.

There six years worth of the kind of flying you get from a O-320 RV-6 here:

There's a lot of "no holds barred" maintenance history in there too.

For more specific details, I set up a small FAQ page:

Whatever you decide on, I wish you luck and hope you end up with an RV. I
can honestly say that buying an RV was the best flying decision that I ever
I'm worn out. I need to rest up a bit before I get a response to my last move on the word game - there are only seven letters to play at a time so I don't think I'm going to be able to use 'cordilleran'.

More's the pity. It would probably be worth 12 points or so.

Sunday, August 14, 2011

I was framed!

I've been reading a series of short whodunnits written from the perspective of a defense attorney. And by "written" I mean fill-in-the-blanks-on-the-same-story-over-and-over. Every single one of the five that I have read have been the same story: his client is innocent but every piece of evidence points to an easy guilty verdict for the prosecution. And each time, the defendant has been framed. Oddly enough, they're still fairly entertaining stories.

More entertaining, I'm willing to bet, than my sharing that I read them. It's all in support of the work that we're doing on the airplane, though, so just be thankful that I kept it short. The work in question is the beginning of the dreaded canopy installation. The next month will likely see nothing but canopy work, although we might squeeze in some odd jobs now and then. The canopy starts with a frame (hence....)

The first thing to do is the deepest countersinking that I've ever [intentionally] done. This will hold a screw that will in turn hold one end of the gas struts that will lift the canopy.

Next comes a strange little job. The canopy is already welded together, but there are five holes to be match drilled and riveted. It seems odd that the rivets are required to support the welds, and it also seems odd that I was finally able to match drill holes and have them in alignment when it came time to rivet. Maybe I should have been welding the parts together all this time...

Speaking of welds, the next step is to grind off a portion of the weld in the center of the cross bow so the canopy won't rub against it.

I started out using a much larger file but it was hitting areas that I didn't want filed. I switched to a smaller file.

Then I test fit the canopy.

After attaching the struts to the screws....

I had to cut off all but two protruding threads.

At that point, the frame was ready to be attached to the airplane.

With the canopy frame, floor boards, seat backs, cushions, and seat belts installed, I thought it was time for another trial fit. Here I am, framed by the canopy frame.

This seemed a good stopping point, particularly since I won't be in the shop again until at least Wednesday. I did some research and found that the drilling of the canopy plexiglass is fraught with opportunities for cracking the area around the drilled holes. The best advice (as near as I can tell) seemed to be to use a manual drill to reduce the chance of a bit grabbing hold of the edge of a hole and creating a crack. I went out looking for one, but it seems that in these days of ubiquitous electricity a hand drill has become something of a specialty tool. I found one at but it will take a few days to get here.

That's not a problem since at least the next two days are going to be miserable as I prep for one of the most undignified and uncomfortable medical procedures known to man. And, things going the way they always do for me, the late week newspapers will be headlining stories about the medical breakthrough that has replaced colonoscopies with a five minute, hassle-free alternative that has been waiting in the wings for just the right time to emerge.

You're welcome.