Thursday, July 2, 2015

Automating the Autopilot

I love my SkyView.

I remember back in my RV-6 days ogling the demo units at Oshkosh, mentally adding up the costs that would be associated with retrofitting such a system into Papa Golf, and rapidly deciding that I was not likely to ever enjoy flying with modern avionics of that sort.

I say this because I don't want the following to be viewed as criticism of this wonderful piece of kit.

So here it is: the autopilot is something of a persnickety pain in the posterior to operate.

You have a choice between Simplified Controls or Complex Controls.

With the simplified controls, there are only two pertinent soft buttons: TRK+ALT and HSI+ALT. They both do the same thing, more or less, with the only salient difference being whether the directional control is to be based on the Nav source (typically GPS in an RV-12) or a magnetic heading as set with a little 'bug' configured through the use of a knob on the SkyView.

In typical operation, what happens with the SC ("simplified controls" in a simplified typing style) is that I already have a GPS course set in as I taxi to takeoff. After takeoff and with a 1,000' of air below me, I will press the HSI+ALT button. That will cause two things: first, the autopilot will enter a turn to capture the GPS ground track, and it will lock the altitude at my present height, regardless of what altitude I want to climb to.

Here's where the limitation of the stock SkyView comes in: it only has one knob for adjusting things like autopilot altitude, vertical speed, GPS track/mag heading, barometric altimeter setting, etc. To set the function that is to be changed, you press up on the knob (it acts as both a rotary setting knob and a little control joystick) to select the function, then press to the right to set that function, then rotate the knob to adjust the value.

It's somewhat burdensome.

I had gotten into the practice of setting the knob function to ALT just before takeoff - this would make it easier to press HSI+ALT and very quickly reset the target altitude to my desired cruise altitude, Later, if I wanted to set the directional control to TRK/HDG, I would have to go through the knob function setting again. This is not uncommon; I often use the TRK setting to offset my course when I see traffic heading right at me, or when I want to position my arrival at the destination airport to a more suitable spot in the sky for a pattern entry.

While enroute, the autopilot still needs a lot of attention if there is any vertical lift/drop component in the current weather (which is almost always the case) as it tries to maintain a constant altitude. If it detects that it's holding control pressure against a rise or drop for any appreciable period of time (just a few seconds), it will post an alert asking for TRIM UP or TRIM DOWN. It generally alternates between the two. A more sophisticated autopilot would know how to manage the trim setting by itself.

These are, of course, minor irritations when compared to having no autopilot at all, but still... if only there was a way....

There is.

Dynon doesn't consider the SkyView to be suitable only for little LSA airplanes like mine. In fact, if it wasn't for the cost/benefit ratio being to dominantly weighted towards benefit, it wouldn't make much sense to use such a capable device in a little bird like mine.  But when you consider, say, an RV-10, which is likely to be used for lengthy trips and in inclement weather, having more granular control over the autopilot is a must.

For this reason, the SkyView also provides a more complex set of menu items, but this complexity comes at the cost of requiring much more interaction with that single little knob. This would not do, so a set of optional panels was created.

These little panels provide the buttons and knobs required to have much easier access to the complex settings, and additionally interface with the trim system.


You can buy these from Dynon or any of a plethora of vendors, but what you will get is a box containing the panel and the pins and backshell for making the required connectors. You can also buy them from Van's for only a little bit more money (Van's is very, very fair in their markups) and get a complete cable harness that is already built to work with the big junction box and the two panels. You also get the required pieces/parts to install the panels in the, well, panel. Plus... instructions!!

Counter to my normal process, I actually read the instructions all the way through before starting. This was intended mostly to learn what tools and supplies I would need. On the tool front, I was going to need a Dremel-style rotary tool and a reinforced cutting disk.  The rotary tool was under $20 from Harbor Freight, but I went name brand for the cutting disks.

I've had bad experiences with these cutting disks - they are, in fact, the scariest tool I ever use. The disk is normally held onto the mandrel with a little screw. Don't tighten it enough and it can work loose and release the disk into flight.  That's not good. Get it too tight and you can crush the area of the disk under the head of the screw and cause it to fail. Again, a flying disk.

Dremel has a new way:

I left some of the mandrel exposed - the cutting disk is NOT a precise tool and the areas where I would be cutting don't offer a lot of room. Leaving the mandrel out a little bit would make it easier to get the cutting edge where I needed it.

DO NOT DO THIS!!  Get the mandrel all the way down into the chuck of the rotary tool.  You'll see why.

Here's everything I thought I would need, minus what Van's calls 'PVC Tape,' which no one at Lowes had ever heard of. I went with Gorilla Extra Tough Duct Tape as an alternative. The 'LIGHT' package is disposable plastic drop "cloth."

The instructions start with positioning the template for the two cut-outs that will have to be made in the panel.

Before doing that, I went ahead and removed the avionics cover.

I shouldn't have - the template needed two of the nutplates to hold it in place.

Then the radio is removed. That's a very easy thing to do.

Then the SkyView screen is removed. I never did figure out why as it wasn't really in the way of anything.

The drop "cloth" is used to create a catch for all of the metal shavings and stuff that will be flung about during the cutting of the panel holes.

And then... the first cut (in a technical sense, I suppose)

Rats. I hope that doesn't turn out to be important.

Then you go through a convoluted process of using a scribe to mark the outer boundaries of the slots, followed by using a Sharpie to draw the outline. The same result could have been achieved more easily simply by drawing boundaries outside of eight of the twelve holes, although that could lead to disaster if you selected the wrong eight.

This is where the PVC tape has been replaced by the Gorilla tape. I don't know if it made any difference. I suspect the PVC tape might have protected better against accidental contact with the cutting disk than the duct tape did. The blue tape is to provide a color contrast when cutting.

Despite their power and convenience (or because of it!), these cutting disks are frightening to use. I would have much preferred using something more protective than just safety glasses. I've had enough of these disks come flying off that I have heartily distrustful of them.

It didn't take much cutting to figure out why the disk/mandrel should be fully pushed down into the chuck.

Luckily, the disk flew away from me, not towards me.  I went back to Lowes and bought another mandrel, and you can bet that I got that thing all the way down into the chuck this time.

Like I said, it is NOT a precision tool.

After dressing up the rough edges and cutting a little more off of the bottom, the first panel fit in.

The drop cloth did exactly what its name implies: it dropped all of the crud right into the seat.

Except for the stuff that attached itself to my arms.

Once both of the panels are in, more holes are drilled and nutplates are installed.  That was the worst part of the entire project.

I didn't use the screws provided by Dynon. The hex head in them is too small and, at least in the case of the SkyView display, trying to get them into nutplates (which are in essence lock nuts) can cause the hex edges to get rounded out. I decided to use the same size screw (6-32) with larger cap heads. These are typically used in R/C airplanes, so I just ran up to Hobby Town to get them.

A little rant here: as I was trying to find enough of the size I needed (they had only one pack of four in each size), I overheard the store owner griping to another customer about how online stores are killing his business. Well, yeah. I was willing to pay a little more for the convenience of getting them right away rather than having to wait for shipping, but he didn't have them in stock! I'll bet Tower Hobbies does...

For the wiring, the old autopilot plug gets disconnected. I could probably cut it out of the plane entirely, but as it weighs only a few ounces and would be hard to replace... I just tied it down and left it.

The SWITCHES connector has to be modified. The new autopilot panel becomes the King of Trim, so the three existing trim switch wires have to be removed.

I hate pulling pins. I hate it even more when I'm supposed to remove pins 15, 18, and 19, but remove 15, 17, and 18. By the time I realized my mistake, I had three unmarked wires dangling loose with no way of figuring out which one was in spot 17.  I had to go back home and consult the wiring chart to determine which pin at the other end of the wire should have continuity with pin 17.

It's pin 21 for those keeping score at home.

The three old wires just get covered in heat shrink and tied back out of the way.

The plugs are easy-peasy to install.

Then there are changes to be made to the WH-00007. This is the worst part of all of the wiring. It was problematic during the install (wiring mistake by Van's) and it came up again when working on someone else's plane. The problems come from being one of about 40 builders that got caught between the transition from the older Dynon D-180 to the newer Skyview. It's in a horrible location under the panel, and nothing good ever comes from touching it. This resulted in yet another trip home to consult the wiring diagram.

The Van's instructions for the configuration updates required are very precise. So precise, in fact, that I was lulled into thinking they would also be very complete.

They were not.

They skipped an essential step.

That caused no small amount of consternation and self-doubt as the panels didn't work. Naturally I suspected I had done something wrong in the always suspect WH-00007.

I could find nothing wrong, so after far too long I finally resorted to the what-should-have-been-obvious fallback of running the Network Detect function.

Ta-da!!  There they are at the bottom of the list.

I've only had a brief opportunity to try them in flight, and even that was from sitting in the right-side seat while letting another builder (who's only a couple months from his first flight) practice takeoffs and landings in my plane. They seem to do everything I want, although I wasn't able to tell of the auto-trim is actually working.

Tuesday, May 26, 2015


Yes, it has been awhile. It's not that I haven't been flying, for I have, but while the kind of flying I've been doing is great fun for me, it isn't the kind that generates an interesting story. 

I've been giving rides. It may seem odd, but one of the most gratifying things I do with the airplane is to share the experience with people that have never been in a small plane, much less having taken control of an airplane in flight and experienced the absolutely unique feeling of being able to control a thousand pounds of metal in three dimensions with no more effort than it takes to stir cream into coffee.  It never fails to elicit the type of uncontrollable smile they haven't felt since they first cuddled with a puppy. Seeing and hearing the utter joy and exuberance in their voices revitalizes my love of flying like nothing else.

Seriously, I challenge you to look at that face and tell me I am exaggerating! 

I'm not going to tell you her real name - we're going to have a little contest to see if you can figure it out for yourself. There are two clues that should lead you to the exact answer. For now, I'll say just that she is a business relationship from the day job that has not only never ridden in a small plane, but also had never visited the Island-Based Frat Party of Put-in-Bay.

She did a fairly decent job of flying us in the general direction of north, but her real value came after landing when she spared my aging back the effort of pushing the plane back into a parking spot.  I'm not kidding: she insisted on it!

I swear, if I couldn't have an airplane I would have to consider something like this boat.

Between it being a Friday and the last weekend before the summer crowds, it was a great day to be on the island if, like me, you don't enjoy the madding crowds. The restaurants were all open, but there were no long lines of hungry people waiting to be seated.  It was a pretty warm day and we had a long, hot, bumpy, and slow (22 knot headwind) ride back waiting for us at the other side of lunch, so we opted for light salads. Well, that and the fact that I'm starting to lose my boyish figure to the ravages of age and, in no small part, a potato chip addiction.

Her? She just likes salad.

If you weren't able to guess her name, just hit the 'Play' button:

The next flight was with a temporary contractor at work. Dave is one of those guys that, again much like me, has struggled to keep up with the not inconsiderable expenses of earning a pilot's license. He saw the pictures of airplanes in my office (in the area I call 'Keurig Corner' chased me down to introduce himself. Having heard his plight, I couldn't help but invite him out for a ride.

It was one of my more routine rides - Urbana for a meal and a quick tour of the B-17 restoration - but he sure did enjoy it. If nothing else, I sure know how to show a guy a good time!

Oh, wait.  Phrasing. Gotta be careful where I say things like that!

One of the coolest things about the B-17 hangar is that they'll let you climb up into the C-47 and pretend to be a real pilot.

The Norden bombsite and Sperry gyroscopic mount are irresistible to me:

Dave was intrigued by the old fella that flew in B-17s in the war. He was describing a unique feature of the B-17 that they're rebuilding. This particular plane was one of only a handful that was equipped with a belly camera - it was used to take back photos of the target to help assess the damage inflicted on the raid.

The machine guns look authentic, but they're actually reproductions built by the guys working on the restoration.

This is the 'before' tail.

It seemingly was deemed easier to just build a new one.

These are the drawings being used to build to replica guns:

There is a Life Flight helicopter based at Urbana too. They carelessly left the doors hanging open and unattended.  Fancy!!

We flew over this field on the way back - I've never seen this before. I have no idea what they're doing, but it sure looked great from the air!

In something of a change of pace, I actually took a ride myself!  I was invited by co-worker to ride over to Indiana to attend the Indianapolis 500, something I've never done before.  Why? Well, madding crowds, that's why. 

It wasn't too bad going in...

We parked in a neighborhood adjacent to the track where nearly all of the homeowners were charging $20 to park in their yard.  We got a bonus at the house we parked at, though: we got to autograph the back of their garage! My name is in there somewhere, as is that of one of my hostess's brothers-in-law.

There were three brothers-in-law in addition to her husband and, as brothers will, there was plenty of lighthearted back and forth. We were in a car following them to the track when the hubby started grousing that they had missed the 30th St. exit. They then proceeded right on past 38th St. too, which did not go without another comment. Finally recognizing their error, they exited at Lafayette St. to head back to 38th.

I mention it only because it set me up perfectly for something that happened later. We were up in our seat in the Turn 3 grandstands waiting for the race to start when the PA announcer called our attention to the approach of the Red Bull Flight Team, who were going to make a flyby. We all dutifully looked out past the short chute between turns 3 and 4, and sure enough, there they were.... turning around and heading back to whence they came, well before accomplishing anything remotely like a flyby.

I simply couldn't help myself: "THEY GOT OFF ON %&(#* LAFAYETTE!!"

Bwahahaha!  I'm still laughing at that one!

Jim Nabors no longer sings Back Home Again in Indiana," but they still release the balloons.

The race got off to a slow start, what with one of the female drivers rear-ending the eventual winner on the pace lap and another car falling victim to an oil fire. It was ten laps before they got down to real racing.

Racing is a lot more fun to watch if you have someone to root for. I had two. One was a rookie whose name I was given as part of a betting pool run by the people at whose house we parked, the other was my old racing buddy, Oriol Servia.

Sure, it was just a video game race, but still...

He seemed to enjoy it, even though he was only able to beat me by a few seconds!

Here he is racing a real car:

It didn't take long for my raffle driver to fall to the wayside.

You know you have good seats if you're sitting by the spotters!

Oriol let me down too. Why he couldn't have done that while I was racing him....

Remember that it was easy to get in? Yeah, not so much on the way out. This was only the start of a two hour trek during which we moved somewhere on the order of ten feet. Oh well, it was sure worth it!!

Here's a little snipped of what it looks like from the bleachers:

All in all, it's been a damn good May.