Sunday, November 30, 2014

Vertigo

Vertigo /ˈvɜrtɨɡoʊ/ (from the Latin vertō "a whirling or spinning movement") is a subtype of dizziness in which a patient inappropriately experiences the perception of motion (usually a spinning motion) due to dysfunction of the vestibular system It is often associated with nausea and vomiting as well as a balance disorder, causing difficulties with standing or walking.

Auto-rough /aw-tow ruhf/ referring to a humorous term used by pilots when flying over hostile terrain or water at night. Their perception or imagination is that the engine(s) sound like they're running a little rougher than when flying over more friendly terrain.

You may remember my recent incident with a rough running engine on a flight in which I was enduring less-than-optimal weather and terrain. In case you missed it, here is a video synopsis:



My first thought was that I may have been feeling the effects of a fouled spark plug. It didn't seem rough enough to be caused by the loss of an entire cylinder, but it also didn't feel like it was purely auto-rough either. In any event, it was enough to ground the airplane until I figured out what was going on.

The first step was to remove all four spark plugs from cylinders #1 and #3, which are the two that are located on the right hand side of the engine, Visual inspection showed no fouling problems at all.  In retrospect, an easier way to do this would have been to run the engine and turn off each of the two ignition systems individually. This would serve to isolate the fouled plug if, in fact, there was one.

Having ruled out an ignition problem, at least with regards to cheap, easy repairs, my thoughts turned to the carburetors. There are two of them on the Rotax 912, and each is responsible for the two cylinders on its respective side of the engine, So more specifically, I began to suspect a problem with the right hand carb. Lending some level of credence to this theory is the fact that there is a current Service Bulletin in effect on the 912 engine, and it has to do with defective carb floats absorbing fuel and becoming too heavy to effectively manage the fuel volume being fed into the engine.

The serial number of my engine is too low to have been caught by the SB, but not so low as to rule it out entirely, especially given the symptoms I was seeing. The nice thing about the SB text is that it includes directions for testing the floats for an overweight condition. You simply drop the float bowl and take the floats to a scale for weighing. If the sum weight of the two is less than 7 grams, you're good to go.

Now, when I say "simply drop the float bowl," I am ignoring the fact that the drip tray underneath the carb has to be removed. I'm not sure what that entails in airplanes other than the RV-12, but in the 12 it means removing the entire carburetor. On the right side of the engine, that is a little tricky in that it is a fairly cramped area. I managed to get it done, and the floats weighed in at a healthy 5 grams. This was good news because Rotax has yet to release a replacement float, and when they do they will be wildly in demand, It was bad news, though, because it had exhausted my troubleshooting expertise.

By now there will be readers shouting at their screens, "What about the carb balance? Have you checked that??!?!!?"

And just now, a whole bunch of other readers are saying, "Whhaaaattt???"
Many pilots are flying on the 912 series of four stroke Rotax aircraft engines. 
One of the areas that are critical for the proper performance of these engines is that the carburetors be properly set up and maintained. 
The 912 series of engines use an altitude compensating Bing carburetor. These are very reliable, and literally trouble free if properly set up and maintained.
The compensating nature of the two carbs is intended to keep them in sync with regards to the power being delivered to each side of the engine. Different power per side = rough engine. They are kept in sync by using a pair of vacuum gauges plugged in between the two carbs. We call this carb balancing.

This is a preview of a training video on the subject. Towards the end of the short video, you will see the adjustment being made. What you can't see, feel, or hear, is what it's like to do this behind the propeller of a running engine on a 27F degree morning trying to adjust those tiny nuts while they're vibrating up a storm and your eyes are watery from the frigid blast of air.

It is a distinctly onerous task.


So, why didn't I immediately consider the carbs being out of balance? Two reasons.

First, I was distracted by the Service Bulletin. It provided what seemed to be an obvious cause.

Second, the carbs had been balanced less than 50 hours ago, and carb balancing is done on a 100 hour cycle.

And, if I'm being entirely honest there was a third reason. What might that have been? Well, see above. It is a distinctly onerous task. Psychologists call this "denial" and/or "rationalization."

I called in a mechanic.

He listened to the engine for just a few seconds before determining that it was, in fact, a problem with the carbs and that the most obvious thing to do was to attempt to balance them. I was still in denial. I had always assumed that as long as I didn't diddle around with them, they would stay in tune. The mechanic squashed that idea like a flatworm under a steam roller: if that was the case, why would you need a periodic inspection?

Well, yeah, when you put it that way...

So.... more than a little embarrassment on my part, but I got the last laugh:

I made him stand behind the prop of a running engine on a 27F degree morning.

It obviously cost me more in dollars than if I had done it myself, but I figure I gained sufficient value: the peace of mind that comes from having a knowledgeable expert do the work while I watched from the sidelines comparing his professional technique to the way that I've been doing it, and the new found knowledge that if I ever get into more trouble with the engine I now know where I can get help.

Sunday, November 23, 2014

Business Travel

So, I had occasion recently to travel to San Francisco on business. There was a time in my professional life when I enjoyed trips like this, but over the years they have lost quite a bit of their appeal. Co-workers that don't travel are known to make statements pointing how much better it would be to travel than to be stuck at a desk, but they should ride a few miles in seat 37E before making such judgments. And there is no 1:1 match between travel hours and desk hours.  I'm not saying that there isn't great benefit to the changes of place and scenery, mind you; I'm saying that it is not a cost-less transaction.

I am going to share an account of a recent trip as an example.

In any event, this time around it was going to be two solid days of travel to attend what was scheduled to be a six hour meeting. Time is on your side on the outbound trip, through, because there are early departures heading west and you gain another three hours as you traverse the time zones, so I figured I'd squeeze in a few time-filler meetings into the early afternoon, too.

It is, after all, corporate HQ, and I've worked with quite a few people out there for years and never met them in person. I figured I could get someone to tour me around to meet people.

I planned the trip with an outbound flight on Tuesday, since the important meeting was on Wednesday, and the return trip on Thursday rather than taking the red eye Wednesday night. Those are wicked bad if, like me, you can't sleep on an airplane.

The return trip would be the opposite of the outbound (well, duh!), by which I mean it would be a late morning departure and a very late evening arrival back at home. As you can infer from the above, I prefer an early morning departure when I have a choice. The reason for the later departure on the return leg is that I have far less control over my transportation to the airport than I do at home. In San Francisco, I would be dependent on BART, which is the acronym by which their subways/trains operate, and I have never learned how to predict how often the airport-bound trains run. Leaving a little later takes off some of the time pressure.

The nice thing about departing early from home is that the TSA line is often brutally short, so you don't have to budget in a lot of time. You would also think the parking garage would be empty early in the morning, but such was not the case this time around. The Monday travelers all got there before me.  I climbed the ramp all the way to the top floor which, being exposed to the weather, ought to come at a lower price.

The open spot that I was eventually able to find met me with bracingly cold wind chills. I didn't have a thermometer, but I estimate the temperature was hovering somewhere around five below Fairbanks, Alaska.

As predicted, though, the TSA line was in fact just about as short as could ever be hoped for, which is to say "non-existent." Seeing nothing but wide open lanes, I took the shortest, most expedient line, a decision for which I was soundly chastised. I was informed by the agent performing the ID check that I had used the "wrong line."

I turned and looked behind me, only to see absolutely no one there, and no other check gate that I could have arrived at through following a less efficient path. No, all lines led to her, and there was no one in any of the lines.  Apparently I was supposed to go through the empty mouse maze rather than take the shorter VIP line, even though I was the only one there.

You really have love the demeaning, lockstep mentality of federal agencies.

The fun had just begun, though. As I was getting ready to remove my belt before walking into the peep-show booth, one of the agents told that removing the belt would be unnecessary. Well, to be fair, his exact words were "you should be alright."

It was foolish of me to fall for such a squishy statement. Sure enough, the agent that greeted my after the peep-show asked whether I was wearing a belt. It was patently obvious what was about to happen.

Yep. The Grope.

Ick.

Once at the gate, I took a look at my boarding pass and was delighted to see that I would be boarding in Group 2. That was important because it drastically improved the odds that there would be room in an overhead bin for my luggage. Now that airlines charge at least $50 to check a bag, it is not surprising that no one checks a bag unless they absolutely have to. Because we would be flying in a small, old, creaky MD-80 (aka "Mad Dog") that was designed before the time when checking baggage was viewed as something akin to having a root canal, bin space would be at a premium.

Since I normally get stuffed into Group 4 or higher, it was welcome news indeed to find myself in a much better group. Note, however, that while one could be forgiven for mistakenly thinking that Group 2 would be the second group to board, airlines these days have more preferential boarding groups than Baskin-Robbins has ice cream flavors.

For some unknown reason, we boarded late. Figures - I had a pretty tight turn in Dallas and wouldn't be able to absorb too many delays.

All went well, though, as I scored both adequate bin space and a very pretty female companion in the seat next to me. Between the generous group assignment and the attractive travel companion, I should have known that things were most assuredly not going to continue to turn out as well.

Karma simply doesn't like me that much.

We pushed back from the gate ten minutes late, but I wasn't worried. They can usually make up some time in flight. Ah, here's the captain on the PA getting ready to tell us that the delay will ultimately not matter because they can just burn a little more fuel:

"Good morning, folks. Sorry for the late departure. We can usually make up the time enroute, but we're going to be flying into some strong headwinds today. We might be a few minutes late"

Sigh. The stress ratcheted up a notch.

At least we were away from the gate and taxiing, though, and with our close proximity to the runway, it shouldn't have taken long to get to the runway.

That's why I got quite suspicious when I noticed that we had been taxiing around in circles for twenty minutes, I've flown enough to know that isn't normal, and I was keenly aware of the time slipping away. Eventually the captain came back on the PA and explained that they were driving around trying to warm up the plane, which had been sitting out all night in temperatures as low as the North Pole of Pluto, which had presumably caused the flap position lights to not operate correctly. A few minutes later, they were.

Off we went.

I suppose it isn't all that surprising to have problems like this with the ancient equipment that they use for this route. Look at this thing, resplendent in its peeling paint and obvious corrosion:


I would NEVER leave the hinge of a flight control with corrosion like this:


Once at altitude, the slide into Karmic punishment continued with the coffee cart. As the service cart came down the aisle, my Pavlovian responses were triggered by the smell of hot coffee coming my way. I stared at that cart and measured its progress like a lion watching a gazelle stroll towards the water hole.

Finally it was my turn. As the male flight attendant took my order, one of those eerily prescient moments that I suffer from now and then flashed through my mind:given my visceral need for my morning shot, they surely will be out.

They were. No more than five drops poured into my cup.

They eventually were able make another pot, and were actually so apologetic about my brief wait that they even gave me a refill after I gulped down the first one. Hmm, maybe things were going to be okay after all, even though an on-time arrival was out of the question.

The dice were rolling across the felt at this point - I would either make my connection or not.

The flight crew made up as much time enroute as they could, and tried to make up even more with a slam-down arrival at DFW followed by very energetic braking to make the earliest possible taxiway.

Looking at my watch, it looked like I had 20 minutes to get to my gate for the next flight which would be just as they were starting to board. I might still make it in time to board with Group 2. Again, that was important. When it comes to getting on the plane, it doesn't matter what group you're in if you're late. A good boarding group is like a door prize: you must be present to win.

But there we were, taxiing in with plenty of time and everything looking good until...... we stopped.

We stopped!

I knew exactly what was coming next.

"Well, folks, we did all we could to get you here quickly, but there is no gate open for us."

We sat there for twenty minutes.

On the plus side, connecting flight gate assignments were made over the PA as we waited for the gate. We would be deplaning at gate A33, and my next flight was departing from gate A37.

That couldn't be any better! I'm always reluctant to connect through Dallas because the place is notorious for gate changes. And because they have at least four terminals, your connecting flight can be miles away. Having to only go four gates in the same terminal, well, that's a lottery winning level piece of luck. When paired with Group 2, it should have been a cakewalk.

I was pretty far back in the plane, though, and those two cups of coffee had run my mood though its normal course. My caffeine-fueled mood starts at exhilaration and inexorably works its way to crankiness, which is where it was when I had to wait patiently (or at least give the appearance of such) for the people who did NOT have connecting flights to lackadaisically grab there stuff and amble up the aisle as if they were listening to Mendelssohn's wedding march or a funeral dirge.

I had already missed the beginning of boarding time by the time I got off the jet, but with only four gates to go, at least I wouldn't be in danger of missing the flight entirely.

As I came out of the jet way and quickly got my bearings, I couldn't help but notice that I was already at the desired gate, A37.

Whaaaaaattttt? What happened to arriving at A33 and ambling on over to A37? And where was my plane??

The San Francisco flight had been moved to gate C11, and I had about four minutes to get there.

That was not good news. I would have to get to the end of Terminal A, go up an incredibly long escalator, catch the monorail to ride over to Terminal C, and find gate C11.

I arrived at the gate out of breath from my exertions (no running, though, as that really isn't seemly when dragging a suitcase) and rushed down the jetway only to some to a screeching stop at the end of a line of people that were still waiting to embark.

I stood there for another twenty minutes as the line did not budge an inch.

That gave me plenty of time to stew about the inevitably having to gate check my bag and deal with baggage claim in San Francisco, when I was wondering just how it can take so damn long for people to sit down.

That last part was the caffeine talking.

Maybe. The adrenaline released during the hectic arrival may have contributed.

As I finally got on board (they delay was for a mechanic to fix a 'seat problem', whatever that means), one of the flight attendants took pity on me. There was no more open bin space to be had back in coach (not surprisingly), but she would let me use some space in first class.

Well, at least one of us was having a good trip!

Hey, speaking of stress, did I mention that I lost my cell phone the day before the trip? Yep. A three day trip with no texting, no email, no internet, etc.

It can be done, of course. People used to do it all the time. And you can go can swim with your left arm tied behind your back:  it's possible, but it's not a great deal of fun.

Monday, the day I lost the phone, had not been a great day. It was to be the only day that I would have to drive to work for two solid weeks due to the business trip and a week of vacation next week, so naturally it snowed, thus ensuring I wouldn't have to miss out on a lengthy winter commute.

I leave early enough in the morning to blaze the trail for the salt trucks and plows in order to avoid the inevitable traffic snarls as thousands of people that seemingly just learned how to drive the day before hit the roads (and each other), but it's still a pretty stressful drive. I would have preferred not to have to do it.

I ended up doing it twice.

I hadn't realized that I couldn't find my phone until after I had already gotten home from the office. A number of increasingly thorough house searches hadn't found it, so the only thing left to do was to return to the office to look there.

It was not there.

As frustrating as Monday had been, at least I was able to console myself with the thought that I would have a relaxing Tuesday - all I had to do all day was sit in an airline seat - how bad could that be?

As we've seen, it hadn't been completely distress free. Fortunately the flight to San Francisco was okay. I had only been able to score a middle seat, but it was towards the front of the plane and had the few inches of extra leg room that they try to sell to the people crammed in between more densely packed seats in the back. It's a cynical business practice, but they're struggling to make ends meet now that everyone has started avoiding the expense of checking their baggage. Just watch: it's just a matter of time before they start charging for carry-on bags too.

We're pretty much left to our own devices when it comes to trip planning, from the selection of airline and hotel all the way down to strategies for getting from the airport to the city. This is how I found myself riding on the creaky old jets of the aging US Airmerican fleet versus the typically nicer 737s of Southwest, my personal airline of choice. It came down to price: $700+ for Southwest, $350 for US Airmerican. It's not my money, per se, and no one really gives a fig in the big picture, but travel expense comes from the business unit's annual expense fund and you wouldn't want to come up short towards the end of the fiscal year - there is definitely value in face-to-face meetings and they are a resource to be jealously guarded.

As such, I broke myself of the habit of taking a taxi (roughly $50) and taught myself how to use the subway. It's called BART in the Bay Area, and it only costs $10. I use it when time and baggage allow.

It's a healthy walk from the arrival gates to the BART station, but I got lucky and got there just as a train was pulling in. There's only one line that runs down as far as the airport, so it's impossible to get on the wrong train. You can see it in the lower left corner:


I would be going to Montgomery St., and I remembered it as being a roughly twenty minute ride. I also remembered that it was fairly important to emerge from the correct set of stairs lest you find yourself on the wrong side of a busy street.


Bingo, there it is!


It's a big place!


As part of my private tour, I got to visit the outside of my boss's boss's office. The view is substantially better than that of my own office, which overlooks a parking lot, but other than that it was somewhat less spacious/palatial than I would have imagined. Although, if you consider that my ranking in the hierarchy would have me sitting in a cubicle rather than in a closed door office if I was an inhabitant here rather than in low-rent Ohio, well... things are different when office space costs are measured in the hundreds of dollars per square foot.

I can do without the view, using that math.


My hotel room, on the other had, actually was palatial. As I said, we do have quite a bit of latitude on hotel selection, but the pickings are slim in San Francisco. It is a year 'round tourist attraction, in addition to being rife with other corporate offices, so rooms command a premium. It was hard to find open rooms at all, much less low cost digs. This one was the lowest I could find (they discount it on account of the not-very-comfortable Murphy bed) at $360 per night. That price is a strong inducement to return home on the red eye flight rather than spend an extra night, but because I am unable to sleep on an airplane, the Murphy bed seemed the better choice.






The slightly inferior bed was the price to pay for a large room with a decent view. This is Union Square:


I didn't see it at first - it was the infernal racket it made ALL NIGHT LONG that made me look for it: they are building a new subway line, and they are working 24/7 to do it. I don't know what the actual purposeful function of this gizmo is, but whatever it does involves making quite a bit of racket.



I am an early riser by nature, but remove three hours from my circadian Rolex and you will find up awake and ready to go at ungodly hours. Thankfully, hotel rooms come with free coffee service, of a sort.



At that time of night, there isn't much to do other than read and enjoy the mechanical rhythms of subway digging machines,


With plenty of time on my hands, I figured it would be easy enough to find alternatives to the hotel's $25 omelet for breakfast. I didn't have my phone with me, of course, but I was able to use my very limited data plan on my iPad to Yelp for a 24/7 diner. It wasn't hard to find one. In fact, I found two, and both were less than a block from the hotel. Of the two, I randomly picked the Pinecrest.



In my never-ending search for decent corned beef hash, I optimistically selected the Pinecrest's offering. It was.... disappointing.


Still having hours to go before my first meeting, I took the other direction around the block back to the hotel and checked out the second diner. They had their menu posted on the window, and I was gratified to see that their #1 specialty was "The Best Corned Beef Hash in The City."

Lucky me! I wasn't leaving on the red eye, so I could try it the next day!


While still not as good as what I make at home, it was far above the average offering, There were actual chunks of meat in there, and the green onions added a bit of zest.  This place will be my go-to for future breakfasts when I'm out that way.


The meetings all went very well, and there were no problems at the hotel other than the frustration of having no less than three room keycards crap out on me. It was especially frustrating when I first tried to get on the elevator to the 11th floor, only to be stymied by a new system in which you enter the number of the floor you want to go to, then insert your keycard to prove you have the right to go there. There are no buttons inside the elevator cab, a fact a learned when my keycard refused to work in gaining access to the floor I needed. I just jumped in with another group (thus proving the futility of this over complicated technology that seems to be searching for a problem to solve) and got as far as the sixth floor before being ignominiously returned to the lobby. This happened repeatedly during my two day stay, and each time I had to return to the front desk for a new card.

My hopes that the return flights would go better than the outbound legs were dashed almost immediately. The first flight was scheduled to provide a slightly longer gap than the one hour window I had in Dallas to change planes on the way out, so I opted to check my luggage through in order to not have to deal with it if things got tight on the turn. As I found out on the outbound leg, it is hard to run between gates while dragging a bag. The odds were on my side this time, I figured, as it would be unlikely to face delays yet again, but I opted to place it safe.

Past performance is not an indication of future performance, but it is also no guarantee against it.

The jet back to Dallas was a 767, which is a 2-3-2 wide body. I was way back in row 37 where I new it would be a wobbly ride, but it didn't seem all that bad for so long as the seat next to me remained vacant. As it got closer to the time when they close the main cabin door, I still had an empty seat next to me. That's a great boon as legroom back that far in the plane is very tight. With only me in the row of two seats, it a much easier to spread out. In situations like these, the last few moments before they close the door are fraught with stress as late arrivals trickle down the aisle, each and every one of them a potential wrecker. I dodged all of the bullets, though, and breathed a sigh of relief as we were pushed back from the gate.

My relief was short lived. Moments after being pushed back, we were pulled right back in. There are only two reasons that I can think of for this. The first, and least likely, being the late arrival of a seat mate, and the second being a maintenance problem. A maintenance problem would be virtually guaranteed to cause another late arrival into Dallas, so the idea of a row companion was actually the more attractive option, despite its innate abhorrence.

It was, in fact, a problem with the airplane, but it was cleared up in just a few minutes. What a relief! We even landed in Dallas a couple of minutes ahead of schedule. Care to guess what happened then?

Too easy, right?

Yep. We taxied off into a vast wilderness of concrete where we parked for 15-20 minutes waiting for our gate to be open. Which, given that there was still an hour to go before I needed to board the next flight, left plenty of time to cross over to another terminal (again). A delay would be a great inconvenience, although if it stretched out too long there may have been an increased risk of incontinence brought on by my failure to plan an airborne potty trip before landing - I got caught out by an early start to our landing approach that force the illumination of the "Stay In Your Damned Seat!" light. It would also eat into the time I had hoped to use to get a bite to eat, since I had had enough of the beef jerky I carry on long trips to keep the hunger panes at bay.

Ain't air travel grand? So much to worry about, so many eventualities to plan against. It could have been worse: the guy sitting behind me missed his connection while we were parked there waiting.

His own fault, really: even if we had gotten to the gate on time, he only had 15 minutes to get to his next flight and most of that would have been spent in the slow motion parade from the back of the plane to the exit. Who books connections that close together?

What a rookie. (Says the guy who was in the same situation slightly more than 48 hours ago.)

Then the shouting started. "Get moving! We're going to miss our flights! Hurry up - what's taking so long??!"

Self important jerks. (Says the guy who was thinking the exact same thing slightly more than 48 hours ago.)

So for me, it all worked out fine. I had plenty of time to choke down a hideous $9 pizza before we started boarding right on time and without a single gate change. Imagine that! The last (and most important) leg was going to be just fine.

Well, by "we started to board" I meant 1st class. They were no sooner heading down the jetway when the PA chirped up with the very last thing I wanted to here: "we're going to stop boarding, the crew has called for maintenance. There's a problem with the airplane."

That has never been good news. Even if all they do is reset a circuit breaker, the paperwork is a good half hour delay. Worst case? I didn't want to think about it. Overnighting in Dallas was the last thing I wanted to consider.

After a half hour of no news, we were informed that there was a brake problem, but they had no idea how long it would take to fix. At this point, there were only two things I was sure of: there would eventually be a gate change as they moved us to a spare airplane, and they would lose my luggage in the process.

Neither of those proved true, though. After an hour wait (they seem longer when you don't know if it's going to be one hour or twelve), we clambered in board and headed home.

The final score does not speak in favor of using the lower cost alternative for future trips. out of four flights, US Airmercan Airlines had four maintenance delays.

There's an old trope that's nearly as time-honored as air travel itself, and it still holds true today:

Time to spare? Go by air!

Saturday, November 15, 2014

Turning Back

The forecast wasn't great, but it wasn't all that bad either. The City Council wouldn't be out grabbing photos to update their tourism brochures with, but with a 4,000' ceiling and 5,000' between it and the next higher layer, it was certainly good enough to get to Jackson, OH.

In theory, anyway.

But it was cold, ever so cold. Twenty degrees in the shade, and with the cloud cover, shade was the rule rather than the exception. This wouldn't present too much of a problem since I would be flying alone, but I recently discovered that the passenger side is quite a bit breezier than my side, Temporary fixes can be put in place, but....


.... it's still not popular.  It doesn't help that the radiator, which doubles as the source of cabin heat, over-performs when it gets super cold. The cylinder heads work at a relatively cold 145 - 150 degrees, and the air that finally reaches the cockpit is an even chiller 50-something degrees.

Not everyone enjoys the brisk temps.

Not.

At.

All.


Things didn't look much like I expected them to - that ugly ceiling was overcast, not broken, but things looked okay further south,

Proceed.


Sure enough, it got a lot better.


There came a point, though, when I thought out would be a good idea to get below the 4,000' layer as the weather was getting noticeably worse. No sense getting stuck on top when 3,500' would be plenty enough, even when considering that I would be over hilly, wooded terrain when I got further south.

Off to the right, there was a great break in the clouds that I would be able to descend through in a straight line, which is slightly preferable to circling down through a hole.  As I throttled back to descend, the engine began running rough enough to show as a vibration in the instrument panel. The right side EGT value also starting jumping around in a most alarming way. You can see a 200 degree differential in the picture below, but it would commonly drop even lower than that.  My guess is a fouled plug - the roughness wasn't noticeable at higher RPMs and if the entire cylinder was gone the vibration would have been much worse and definitely noticeable at higher RPMs.




Not thrilled with the idea of a lower than forecast ceiling that would have me down to 1,500' to 1,000' above the hills combined with a rough running engine, I turned around and headed back, but not before accidentally plowing into a the wispy edge of the ceiling, I was only in the clouds for 10 - 15 seconds, which is not enough to be truly dangerous, but it's not supposed to happen at all. It was hard to see where the edge of the clouds was and I had simply not started the descent or turn soon enough.

Heading back was the right thing to do - it was becoming obvious that the forecast (well, it was actually an observation, so it should have been more accurate) was wrong and that there would have been some question as to what would be going on a few hours later when I came back, had I continued on south,


The poor quality of the observation was explained by the ADSB: it was nearly an hour old.



The 7 miles of visibility was pretty close to accurate though, but 7 miles isn't as much as you might think it is. It doesn't matter in the world of GPS, but looking out the window showed very little that wasn't muted by the hazy air. If push had come to shove, though, I would have been able to find my way back in the same way the early airmail pilots did it: I could have just homed on the flame beacon.


These obviously aren't navigation beacons; these are the methane burns from the local landfill. We have a rather more indelicate name for them in my family: we call them "The Fart Flames."

Even three miles out from the runway, it was still somewhat difficult to see:


I had at least one maintenance issue to deal with when I got back to the airport, but that soon became two. I had a bit of a crosswind on landing and I botched the touchdown such that I landed with some side loads on the landing gear. 

That's not normally a problem, but I also let the nose wheel touchdown. I could tell right away from the rumbling and griping from the nose wheel that I had broken another of the notably weak wheel bearings.

Great.

They're not expensive, but you need a hydraulic arbor press to remove and replace them. I was able to have it done last time by virtue of finding someone that has one, but this seems as if it's going to be a regular task. Off to Harbor Freight for the 12-ton press they had on sale for $109.99 which, as is my luck, they were out of. Not that you could tell from the plentiful 'Take This Tag to the Register' slips, of which there were many.  

Irritating, that, but I won in the end. I was able to order one from their web site for $99.99 and $5.99 shipping.

Saturday, November 1, 2014

Weather or not?

It's a pun, but of course you won't get the joke without knowing what prompted it. As it happens, I had two decisions to make, both related to weather.  They were:

  - Whether or not to move the date of Delta Golf's FAA-mandated annual condition inspection forward, or to leave it where it was and suffer the tribulations of days spent in the cold, cold hangar, and
  - Whether or not to spend the not inconsequential $1,150 to upgrade my Skyview with the ADS-B module.

The first decision was easy.

The second, not so much, but not for the reason you may suspect.  It came down to cost/benefit decision, but not with regards to the lucre. It came down to the difficulty of the installation.

As you may not be aware of the benefits arguing in favor of taking on the challenge of installation, here's some dry, descriptive text:
Automatic dependent surveillance – broadcast (ADS–B) is a cooperative surveillance technology in which an aircraft determines its position via satellite navigation and periodically broadcasts it, enabling it to be tracked. The information can be received by air traffic control ground stations as a replacement for secondary radar. It can also be received by other aircraft to provide situational awareness and allow self separation.

ADS–B is "automatic" in that it requires no pilot or external input. It is "dependent" in that it depends on data from the aircraft's navigation system.
ADS–B is an element of the US Next Generation Air Transportation System (NextGen) and the Single European Sky ATM Research (SESAR). ADS–B equipment is currently mandatory in portions of Australian airspace, the United States requires some aircraft to be equipped by 2020 and the equipment will be mandatory for some aircraft in
Europe from 2017.

ADS-B, which consists of two different services, "ADS-B Out" and "ADS-B In", could be replacing radar as the primary surveillance method for controlling aircraft worldwide. In the United States, ADS-B is an integral component of the NextGen national airspace strategy for upgrading or enhancing aviation infrastructure and operations. The ADS-B system can also provide traffic and government generated graphical weather information through TIS-B and FIS-B applications. ADS-B enhances safety by making an aircraft visible, realtime, to air traffic control (ATC) and to other appropriately equipped ADS-B aircraft with position and velocity data transmitted every second. ADS-B data can be recorded and downloaded for post-flight analysis. ADS-B also provides the data infrastructure for inexpensive flight tracking, planning, and dispatch.

"ADS-B Out" periodically broadcasts information about each aircraft, such as identification, current position, altitude, and velocity, through an onboard transmitter. ADS-B Out provides air traffic controllers with real-time position information that is, in most cases, more accurate than the information available with current radar-based systems. With more accurate information, ATC will be able to position and separate aircraft with improved precision and timing.
So, yeah, dry as overcooked turkey, that. I did you the favor of highlighting the two most salient parts: with ADS-B, I will get weather information displayed on the Skyview, along with improved traffic detection.

The weather capability will provide 'big picture' information by displaying weather radar data directly onto the map screen, and more importantly will also have wind, visibility, and cloud ceiling data for every airport that has weather reporting capability. It looks something (well, "precisely" if you want to argue about word selection) like this:


In the picture above, consider the right side. Imagine this is me arriving in a area of unforecast bad weather, trying to figure out where to land. You might guess I would head for either KTCM or KGRF since they are unquestionably VFR (going in ascending order of desirability: IFR, LIFR, MVFR, VFR), but I probably wouldn't. My first choice would be KTIW because of the much higher winds at both KTCM and KGRF.  I saw 'probably' because other factors would enter into the decision making, particularly the topology of the area. If it was mountainous, for example, I might be more leery of the 2,200' ceiling at KTIW.

Let's hope I never get a forecast quite that erroneous, but.... it can and does happen. Best to be prepared.

This next picture (borrowed from an RV-12 builder who borrowed it from "Karl's picture of the Dynon SkyView installed in his RV-8 displaying ADSB weather and traffic on the right half of the screen"), also shows the traffic display. Note that the Skyview I have also displays traffic, but it does so based on signals received from ground ATC stations. There are places, such as the southeastern region of Ohio, that have radar blindspots and thus provide no traffic information.

That's how a Beech Bonanza ended up nose-to-nose with Kyle and me one day, but luckily a few hundred feet lower.


This next one is an official Dynon screen shot, demonstrating (unintentionally) precisely what not to do with ADS-B. This shows a pilot headed directly into a thunderstorm that appears to be northwest of the airport. The pilot is presumably going to "thread the needle" between the storm and the airport. This is ill-advised because 1) thunderstorms can move pretty fast, and 2) there is an inherent lag in the update rate of the radar information - the data is commonly 15 or so minutes out of date by the time it gets to the screen.  Still, it's representative of 'big picture' weather information which, if used properly, can be of tremendous benefit to someone flying a 700 lb. airplane.

You know, like me.


This is the level of data available if you dig down a little deeper:


So, with all of the glorious benefits, what kind of installation hurdle would give me pause?

Good question.

The problem is with Van's. In the directions provided with the retrofit kit, they detail an installation process that would require me to run a big, thick antenna cable from the top of the comm radio, where they have us mount the new box, all the way back down through the tunnel and into the tail cone, behind the aft baggage bulkhead.  

No one, and I mean NO ONE, wants to do this.

The reason for this lengthy wire run is to provide separation between the existing transponder antenna and the new ADS-B antenna. Let's stipulate for a minute that that distance is an absolute requirement. Others have looked at this and echoed my "No *!^#~} WAY!" sentiment. They have decided instead to mount the electronic box in the tail cone and buy a new wiring harness to carry the signals from the tail cone up to the front of the plane. 

The presumption here is that the wiring harness will be easier to push through the very crowded tunnel than the thicker antenna cable would have been. Even then, at least one or two people have decided against that as well and run the wires forward by routing them along the side of the interior fuselage skin.

Being a good little Van's citizen, I decided I would take the harder road and do it Van's way. As much as I hated the idea of dealing with those little plastic wire-retaining blocks on the fuselage floor, it seemed do-able. Having decided to lean in that direction, I did something I seldom do: I read through the entire process. That's how I came across "remove both flaperon torque tubes."

"No *!^#~} WAY!"

Let's leave it at that for a few moments.

I decided to do some of the routine maintenance first, while I thought about how to proceed on the ADS-B installation.

So, up on the jacks she went. The brake pads were worn just about to where the wear indication would indicate sufficient wear to be aware of the need to replace them, so off came the wheels, if case you're wondering where they are.


This is one of the outer pads compared to a brand new pad. They aren't completely worn away, but at $33 for the replacement set, why wouldn't I just do this every year?


It does require a special tool to de-rivet the old pads and rivet on the new ones, but since any airplane owner, whether the plane is certificated as Experimental or not, can replace brake pads, I've had this tool for years.

Even if I hadn't, it is a very reasonably priced tool at $36.50.

The first step is, of course, the removal of the old pads. This is done by leaving the outer/bottom part of the tool 'open', which gives the rivet head somewhere to go as it is pushed out by the pointy part of the inner/upper part of the tool.



I work on one piece at a time so I always have an assembled piece to use as a reference so I don't get the pad mounted on the wrong side. Here is a new pad laid into position.


The pointy part of the tool is replaced with the conical part, which will squeeze the new rivet into place, and the hole in the outer/bottom part of the tool is filled with what I call the anvil. This will press against the head of the rivet while it is being squeezed.


This is the first new rivet being squeezed into place. There is another rivet in place at the other end of the pad - it's function is to keep the pad from moving out of alignment while the first rivet is being squeezed.

I failed to do this once.

Once.

It's not a mistake that you make a second time.


Before and after: the new pads are in place on the mounting plate to the left. The mounting plate on the right makes me wonder if I've been leaking some brake fluid - it needed quite a bit of cleaning.



The inner mounts are done in pretty much the same way, although they use the larger size of the two rivet sizes included with the pads.



Another before and after:


The oil had been draining (sharp readers will have noticed from the sawhorse picture that the oil preheater was plugged in - this would be why) while I was working on the brakes, so by the time they were done the oil was gone and I could remove the magnetic plug for inspection. There was still oil to leak out once the plug was removed, but it was less, I guess, than it would have been.

The magnetic plug is intended to catch ferrous metals as they swim by in the oil stream to provide early warning of an engine that has decided to self-cannibalize.

Looks okay to me.


There's also a recurring inspection to make - this little probe is intended to show if the PTO journal has cracked.

And no, I really don't know what function a PTO journal is intended to provide for, but my guess is that it provides rotational force for engine attachments like a second alternator.  The RV-12 doesn't come with this second alternator, but planes with heavier electrical load requirements do.  In any event, it can apparently crack without showing any visible distress, so we test for it.


With all of that done, the wheels went back on. I finally broke down and bought a sufficiently big socket for the axle nut. I had been doing this with a big adjustable metric crescent wrench (inside joke), but I couldn't get the nut tight enough to hold the bearing seals in place. As opposed to every other airplane that I have had, these Matco wheels have a rubber seal on the outside of the wheel bearings. This is intended, I think, to keep sand and grime from getting into the bearings. It seems to work; I took the bearings over to the airport mechanic shop to use their cleaning sink to clean out the old grease before repacking with new and the head mechanic there wondered why I was even bothering. The old grease still looked brand new.

Alas, the bearings get repacked every year whether they need it or not. It's really kind of a pain because the rubber seals make it much, much harder to push the grease into the bearings. I tried using the little needle valve that Matco sells, but I was only able to get a little grease in the tiny gap between the bearing and its race (if that's the right word) before having to push the rest in my hand.

So, why the big socket?

The Matco wheels, because of the integral rubber seal, are tightened differently than the older style wheels. With these wheels, you have to tighten the axle nut until the black rubber seal won't turn when the wheel is turned. It takes more torque to get them that tight than can be delivered by a wrench that can only achieve partial grip on the nut due to the nut being down inside the wheel.


Fooling around with all of that routine work gave me time to ponder the ADS-B job. It also gave me time to research why Van's put the antenna so far back in the airframe. Van's (correctly) has a tendency to expect the builder to use the instructions and procedures detailed in the manuals that come with things that Van's doesn't actually make, like the engine, wheels, brakes, and avionics. Oddly, they also have a tendency to provide directions that don't always reflect those provided by the manufacturer.

As such, I thought it might be instructive to consult the ADS-B installation instructions as provided by Dynon. This seemed particularly instructive:
- The SV-ADSB-470 antenna should not be installed within 2 feet (24 inches) of the
transponder antenna.
There's a heckuva lot of difference between 24" and 10'!!

I started looking for a more suitable (for installation, anyway) location for the antenna.

I found one.

Now, before I proceed, I want to say that anyone choosing to install a Dynon ADS-B with the antenna located where I put mine does so at their own risk! At the time of this writing, this antenna location has not been tested in flight.

Disclaimers out of the way, I found a spot over on the passenger side. This location on the pilot's side houses the autopilot pitch servo. Over on the passenger side, it just sits there empty.

I originally thought about putting the antenna doubler on the inner side of the bay, but later decided to move it to the outboard side to ensure that I was getting it as far away from the transponder antenna as possible. Also note that the doubler is turned 90 degrees from its proper orientation in this picture.


I was still a little reluctant to drill a big hole in the belly of the plane, so I procrastinated by installing the electronic unit first.

The radio is easy to remove from the tray, so I got it out of the way. The radio tray stays in because that's what the ADS-B box is going to mount to.

I went ahead and drilled a new hole for the antenna cable to go through.


The next step was to prepare the mounting brackets by installing nutplates. I haven't done nutplates for a year or so, but after doing literally hundreds during the build I figured it would come back to me easily enough.

Maybe not.

I missed capturing the nutplate 'ear' on the first rivet. Note the existence of the rivet but the stunning absence of anything else.

Duh.



It takes some studying of the picture in the installation instructions to realize that the mounts will offset the ADS-B box from the radio underneath it.  Note also that I have screwdrivers that are too long for the job, and screwdrivers that are too short for the job. I had to kludge together a "just right" screwdriver.

The downside of this solution was the reminder that my nice Craftsman 1/4" drive ratchet is slightly broken - it won't hold the socket on anymore. I must have dropped the screwdriver head off of it a dozen times, each occurrence eliciting a harsher or louder epithet than the previous, and in some notable occasions, both.

I'm tempted to test the Craftsman Lifetime Warranty on this thing, but I imagine I would be disappointed.


Here you can see the proper orientation of the mounts. Study it carefully - it's easy to get them backwards, and if you're struggling with a slightly broken tool, the last thing you want to have to do is re-do the installation.

Yes, yes, ask me how I know.



So, again about Van's. I sometimes wonder if they actually field test their instructions. Consider the wiring harness. Just so you can imagine what is to follow, here is the harness as it comes from Van's, albeit after I wrapped it with the plastic wrapper that I use to keep the individual wires getting tangled up like Christmas lights, or angel hair pasta, whichever analogy you prefer. Pay particular attention to the size of the connectors.


Now see if you think that cable is going to be routable as depicted in the instructions.


It wouldn't fit even if that hole wasn't already filled with wires!


I solve that problem in my usual way: I ignored their instructions.

Oh, and the antenna? Easy-peasy to mount, and the location exceeds the Dynon-specified distance requirement by a 10% margin.


Here's how you know it's working well enough to justify a test in the air (the antenna can't pick up the ADS-B signals while sitting on the ground in a hangar) - note here that Van's gave incorrect directions on how to get to this page. You use the System Settings menu, not the Local Display Settings menu. The TX and RX counters indicate that the ADS-B unit is in communication with the Skyview. To be fair, the communication setup was easily accomplished by importing a config file provided by Van's.

They usually get the big things right.


There's still work to do on the ADS-B - the antenna cable needs to be restrained from floating around loose under the floorboards and a new weight & balance needs to be computed. There's also more work to be done on the annual inspection.

Once all that is done, stay tuned for an in-air test of the ADS-B!

UPDATE:

It works just fine with the antenna location I selected: