RV-9A Brake Upgrade

The stock brakes on my Van’s RV-9A are sized just large enough to handle an aborted take off at max gross weight. I have had a couple of occasions where hard braking on landings have resulted in the over heating of the brakes. The stock brake discs are rather thin. The amount of material on the brake discs acts as a thermal sink, so having thicker discs will have more thermal capacity and therefore allow harder and longer braking before the brakes overheat. So why have my stock brakes been inadequate? My RV-9A has a fuel injected engine and after landing on a hot day with a heat soaked engine, the fuel in the tiny distribution lines will start to boil and vaporize. This causes the engine to stumble and quit if the idle gets much below 1000 RPMs. Not being able to have the engine idle below 1000 RPM leads to taxiing speeds that need to be slowed by more brake application. When the brakes are already thermally soaked, you can get brake fade or failure.

Last year on July 4, my wife and I went on a quick flight to go fill up with some cheap gas at a nearby airport, and then to fly along some of the local San Diego beaches to see the holiday crowds. We landed just a bit long at our fuel stop and I tried to make the last turn off on the right side of the runway where the fuel tanks were located when my right brake pedal went soft. I wasn’t able to make the right turn. Thankfully, there was still plenty of runway left, and the last taxi turn off at the end was to the left. We let the brakes cool down, got our fuel, and our braking on the right side came back. My wife gave the go ahead right then and there to go get some better brakes. Having higher braking capacity is an easy choice for increased safety of landings or aborted take offs.

Later that month at Airventure Oshkosh I set out to see what options were available for getting better brake performance. One option was to completely change the stock Van’s brakes supplied by Matco Manufacturing over to brake systems made by either Grove or Beringer. The upgraded brakes from Grove provide dual piston calipers and larger pads. The downside would be that their upgrade kit requires new wheels, which added a lot to the price of this upgrade. I was also not sure if the dual piston calipers would fit inside of my existing wheel pants without trimming or enlarging the opening (and harming the nice new paint job). The Beringer option is also even more expensive and also requires that you update your wheels. The Beringer wheels require the use of more expensive and less common tubeless tires. My conversation with Matco about their upgrades turned out to be the best option. They do sell a thicker brake disc, a wider spacer and longer bolts that use the existing caliper assembly. This “high energy” option doubles the thermal capacity of the braking and allows you to retain the stock wheels and tires.

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Stock, thinner brake disc on the left. New high energy, thicker brake disc on the right.
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A thicker spacer and longer bolts (left side) are also required with the high energy brake upgrade.

At this year’s annual condition inspection I was ready to finally get the brake upgrade completed. My main gear tires were ready to be replaced. I had already updated the O-rings in the calipers to the higher temperature capable Viton material. These O-rings had been in place for the last year and have worked fine keeping the brake fluid in the system even when the brake temps have been high.

I started off getting everything disassembled. I jacked up the airplane and took the wheel pants and gear leg fairings completely off. The wheel nuts, spacers, bearings and wheels also get removed. The tires get deflated and then I removed the valve stem inside the tube. I used a bead breaker to get the tires off of the wheel rims. I thoroughly scrubbed down the wheels with soapy water, and got all of the brake dust off of the calipers. It is a very messy job. I took out the single Allen head bolt that secures the brake flange to the gear leg, and removed the entire bracket which holds the brake caliper and wheel pants.

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The brake flange with the caliper mount and wheel pant bracket.

There are 3 bolts on the wheel halves that hold the two sides of the wheels together along with the brake disc. Reassembly begins with getting the inside of the new tires and tubes coated in talc and inserted back into the tire. A little bit of compressed air will fill up the tube so that you can position it correctly with the valve stem lined up with the red dot on the new tire. The rims get bolted together with the new high energy discs. Be careful not to pinch the tube between the wheel halves.

The extra thickness of the upgraded discs changes some of the geometry with the wheel pant brackets. The stock brake discs run really close to the wheel pant brackets, and the new thicker disc requires some extra space here. The suggestion by Matco was to simply move the mounting of the brake caliper bracket from the outside face of the brake flange over to the inside face. This moves the wheel pant bracket an additional 1/8″ away from the original brake disc location. The brake flange location is set by the single Allen head bolt that secures it to the landing gear axle. Since that location doesn’t change, you don’t need to adjust any of the spacers, wheel nuts and cotter pin locations used to mount the wheels. The wheel pant bracket just sits in the same location and uses the same spacers/washers/nuts/bolts.

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The brake flange is the white powder coated weldment that slips over the main gear axle. It has the brake caliper mount attached on the outside (right side) face.

I removed the four bolts and three spacers that hold the wheel pant bracket to the brake flange. Then I moved the caliper bracket over to the other face of the brake flange, and remounted the bolts and spacers that hold the wheel pant bracket.

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The brake caliper mount is now moved over to the inner face of brake flange to make room for the thicker brake disc against the wheel pant bracket (bottom).

Reassembly is straight forward. You reattach the brake flange with the relocated brake caliper bracket and wheel pant bracket assembly to the main gear axle with the single Allen head bolt. Then on goes the wheel spacers, bearings (re-lubed with fresh grease), the wheel with new brake disc, and finally the wheel nut and cotter pin.

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Fully assembled and back on the gear. You can see the thicker brake disc alongside the relocated wheel pant bracket. The thicker spacer and bolts secure the brake pads to the caliper assembly.

 

I also put new brake pads on the calipers, so that required an initial break in and bedding of the fresh surfaces on both the pads and the new discs. This was done by taxiing at a brisk 30-40 mph and then a hard application of the brakes to quickly slow down, but not to fully stop the airplane. After the brakes have cooled off for 10-15 minutes, the same process is done again.

I inspected the brakes after the bedding process and then I took off for a quick lap around the pattern. I did another hard application of the brakes on my landing to get a feel for the grip of the upgraded brakes. The braking with the new discs felt much stronger.

The last step in this upgrade was to get the wheel pants back on. This was the moment of truth as to whether or not the new location of the brake caliper and wheel pant brackets being moved over 1/8″ inch would affect the reassembly. I was able to line up the existing wheel pant screw locations to the new location of the wheel pant brackets without any problems. The wheel pants and brackets have enough flexibility to accommodate this very minor location change.

The quantity and part numbers from Matco for the upgrade are as follows:

  • Qty 2 – WHLD164-017HE – ROTOR, BRAKE DISC HIGH ENERGY
  • Qty 2 – WHLBSPE5L – SPACER, Long CALIPER E-SERIES
  • Qty 4 – MSCAN4-22A – BOLT
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Annual Condition Inspection 2019

It’s that time of the year again to do the annual condition inspection on the RV-9A! This year I didn’t fly quite as much as the prior years. It was down for a while back in the fall dealing with the stuck exhaust valve. This winter was particularly cold and rainy, so that affected my flying hours. Last year’s annual took a long time, since I had to send out my P-mags for new firmware and a checkup. I’m hoping this year I can get it done quickly. I made a trip up to Aircraft Spruce right before Memorial Day and picked up almost all of the supplies I needed, except I wasn’t able to get my usual case of oil. I only really needed 1 more quart beyond the 5 I still had in the hangar, but they were completely out. I guess that Shell is going through some sort of repackaging change and that is what has them completely out as they switch over. Rumor has it the new “case” size will be a six quart package. I bought the additional quart of oil from the FBO.

Day 1

I started on some of the checks on Saturday, June 8. I took time to really wash off all of the bugs on the wings and tail, then I applied some Rejex polymer coating. I took off the tail fairings and put a wrench on all of the nuts and bolts that hold the tail on the fueslage. I lubed up the bearings on the elevators and rudder, along with checking the trim tab operation. I also lubed up the controls for the ailerons and flaps. Then, I closed up the tail fairings.

Day 2

I went around the pattern twice just to heat up the oil and the Hobbs is now showing 661.1 hours. The oil was last changed back around the New Year, and usually it would be changed out at 40-50 hours or 3-4 months. The oil had only 30 hours and it had been over 5 months. Back in the hangar I took off the cowling and drained the oil. I took out the oil screen from the bottom of the sump and for the first time found just a few flakes of stuff in there. Looked like mostly bits of carbon. A sample of the oil will be sent out for analysis.

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With the help of some hangar neighbors we also did the compression test while the engine was warm. All of the cylinders were mid-70’s, so that means they are all in good shape. I went through all of the spark plug adapters and cleaned up the threads on them. I had already bought the replacement automotive spark plugs, so I gapped them and got them ready to go.  One of the squawks this year involves the fuel pressure sender. I’ve had it trigger a high fuel pressure alarm on a couple of occasions. From what I can gather searching the web, these old VDO style senders that were shipped by Dynon can fail in this manner. They never leaked, but having that bright red LED light up on the instrument panel sure gets your attention. The newer pressure senders are from Kavlico and they require a couple of additional wires (+5V power and ground) be connected. I connected up some appropriately colored wires to the ones provided on the sender and got them fished into the pass-through on the firewall so I can connect these up to the existing +5V power line used by the Manifold Pressure sender, and the ground block. At about 4pm, the temperature at the airport was hitting triple digits, so I called it a day.

Day 3

I was able to spend the entire day (Monday) in the hangar. I’m currently not working, so I’ve got my week days free (I’m still looking for a new Software Engineering Programmer or Manager position). Another hangar neighbor was back from a quick flight before it got too hot outside, and I was able to borrow his borescope to look inside my cylinders. Last year I did a similar borescope check, but I was using my work laptop to run the software and capture the photos of the valves. Since I no longer have that job (or laptop), I just used his to view the valves and didn’t snap any photos. They all looked fine. After that I went ahead and put the new spark plugs back into the cylinders.

I had also taken off my P-mags to inspect them, so they went back on. I’ve been having some lingering “Timing Divergence Alarm” issues on my Electronic Ignition Commander instrument. The TDA goes off if the timing positions are different between the Left and Right P-mags. The engine seems happy by all of the other measures (EGT/CHT/MAP/RPM/etc), but the alarm comes and goes randomly. Some flights it sits there at 2-3 degree difference, which is normal, and other flights it will just jump all around between 2-7 degrees, and the timing advance degree indicated by the P-mag will be slightly different. I decided to block off the Manifold Pressure lines on the last couple of flights and that prevents the timing advance from happening, and they looked OK on the EIC, but I would still randomly get the TDA alarms. The gears on both the engine and P-mags look fine and all of the connections (wires and tubes) were good. Anyway, I swapped the P-mag sides to see if the timing advance difference follows. I also checked all of the spark plug wires for resistance and they checked out. Other items today were getting the oil filter back on and filling up the engine with fresh oil, and cleaning out the air filter. I checked all of the other engine related items on the list, such as fuel/oil lines, exhaust, intakes, hoses, controls, and starter.

Day 4

I started off this morning by removing the spinner and propeller. The prop was in good shape, so no issues there other than some very tiny blemishes on the back surfaces. I had planned on replacing the alternator belt since it had been on for almost 6 years. However, after looking at it carefully, I couldn’t see any difference from the new belt I bought. I’ll throw the new belt in the tool bag and revisit this next year. These automotive belts should last quite a while. While the belt was off the alternator I was able to check it and it was spinning smoothly. I cleaned up the spinner and put it back together and got everything torqued and safety wired on the nose of the airplane. Next up was cleaning off the wheel pants and gear leg fairings. The pants can take a beating being down next to the ground, but I didn’t find anything beyond some light scratches in the paint and lots of dirt and grime.

My next task was to work on the changes required to fit the upgraded and thicker high energy brake discs. I’ll eventually write up this whole upgrade to the brakes in another blog entry, but for now I test fitted the right side and it looks like it all fits fine once the brackets get moved over on the axle. I was mostly worried about having to move the wheel pant bracket over, and then whether or not this affected the existing screw holes alignment. Thankfully, there is a bit of slop and the bracket is only moving about 1/8″ to one side.

Day 5

I finished up the right side main gear with putting on the new brake disc on the wheel, along with a new Desser Monster retread tire. Cleaning up the wheels and brakes is a very dirty job. I spent the entire day doing the new brakes and tires on both main gear legs. I finished off with cleaning the wheel pants and applying some more Rejex coating on the paint. I have to say I really like this Rejex stuff. It goes on and off very easy and quickly and the coating it leaves really doesn’t allow anything to stick to the paint (like dead bugs and grime).

Day 6

The task for today was to get all of the access panels on the wings opened up. There is a service bulletin on the aileron bracket attachment rivets on the rear spar. I took some photos with the smart phone and was able to see that there are no cracks.

I lubed up the controls, and checked all of the fuel tank connections, checked under the wing tips, then moved on to the wiring of the new fuel pressure sender. Getting under the panel is quite an effort, but I was able to splice in the new power and ground lines after moving stuff around under the panel for access. Tip for future builders. Leave lots of slack on all of the wiring runs, and have big service loops so that you can drop all of the wiring down for easy access.

After the new wires were connected, I powered on the fuel pump and saw that the fuel pressures indicated were back where they should be with the new sender.

Lastly, I cleaned off the undersides of the wings and got them ready for some waxing with Rejex. I was too wiped out from my under the panel contortions to start on that. At least the temperature today in the hangar was much cooler.

I’m hoping that tomorrow it will be finished up.

Day 7

Well today I gave my cordless screwdriver a workout. I started out by taking off all of the access panels, bulkheads, seat pans and tunnel covers off. I worked my way from back to front. Nothing really to report except as you put a wrench on every nut and bolt you will find the occasional one that just isn’t as torqued as it should be. I cleaned out the fuel filter, but there was only a few little bits of stuff in there. I got out my shop vac and really took some time to get all of the grime out from under the seats and floor. I use some diluted Dawn ship soap in a spray bottle to get the dirt cleaned up. Once all of the controls were lubed up with some LPS2, I started the process of putting all of the screws back in place. I’m happy to report that I ended up without any extra or missing screws. After that I did the cleaning and waxing of the rest of the fuselage, and cleaned the canopy thoroughly.

At 5pm  about the only thing left to do was to clean up the tools and stuff in the hangar and pull her out to fire up the engine. I did all of the post maintenance pre-flighting and engine run ups, then got the cowling back on. With the new brakes, you have to do some taxi runs in order to bed them so that they have some grip. I did a taxi run, then came back and checked on the brakes and wheels. The bigger discs seem to work well, and they did get heated up on the taxi run. After they cooled off for 15 minutes, I taxied over to the runway, took off and did a lap in the pattern with a full stop landing. The brakes really worked well. I took off again and flew over to Gillespie (KSEE) to fill up the fuel tanks. Gas over there is almost a dollar a gallon cheaper than at Ramona ($4.25 vs. $5.19). Besides, it is a fun quick flight and the weather was still nice there before the June gloom heads in for the night. On the way back to Ramona, I called the tower at the San Vicente Lake reporting point and they cleared me to land from 8 miles out. Another nice smooth landing and some more hard braking to get those discs and pads bedded in, and back to the hangar. I completed all of the paperwork for the condition inspection and took a good look at the wheels and brakes, and then put the wheel pants back on. Now I’m good for another year of flying. This condition inspection was certainly my quickest so far and it still took a solid week of full time effort. If anyone out there claims they can do an annual in a day or two I would be very skeptical. I’m just glad I didn’t find anything unexpected (and I certainly tried), other than finding just one missing screw on one of the main gear wheel pants.

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Ready to go after the annual condition inspection.

Matco Manufacturing Tour

In March, I spent a couple of weeks in Salt Lake City with my daughter. She is living in our rental house there. We are doing some construction on the house, so I drove out there with a bunch of stuff I needed to take to work on. It was just too much to take in the airplane, and the weather that time of year is rather iffy. In fact, it snowed and rained most of the two weeks I was there. I posted a quick note on VAF asking if there was anything happening in the area related to RV’s and flying, and got word that the EAA Chapter 23 in Bountiful was going to get a tour of the Matco Manufacturing facility adjoining the field. I’ve flown into Skypark at Bountiful many times, but I didn’t know that Matco was located there. Matco manufactures the wheels and brakes for the Van’s RV line of aircraft.

At Oshkosh last summer I sought them (and some other wheel/brake manufacturers)  out looking for ways to improve my brake performance. I’ve had some overheating issues with the brakes and was looking for some thicker brake discs. At Oshkosh they did say that they had a “high-energy” (HE) option for the standard Van’s brakes. On my nosegear RV-9A, you have to steer with the rudder pedals and use differential braking as necessary to control your direction on the ground. With my fuel injected engine not liking to idle very low when it is hot, I have to keep the RPM’s up around 1000 or risk having the fuel boil in the injector lines and the engine will quit while taxiing. This means the airplane likes to taxi pretty fast and then you get to use the brakes a lot. I had looked on the Matco web site for these HE part numbers, but wasn’t able to find them to order.

The day before the tour, I took a lunch time drive over to their location and talked with them about getting the upgraded HE discs, which also require some thicker spacers and longer bolts. I ended up buying the necessary parts and then came back the next evening to get the behind the scenes tour.

Here are the photos from the tour that I took.

I will be installing the new upgraded brakes at this year’s annual condition inspection, which is coming up in June.

Flying Stats for 2018

It’s that time of the year again to write up another blog entry to review the flying I did in 2018. This year I did not have as much flying time as the previous years. The total time this year was down to just 122.9 hours. The airplane ended the year with 634.1 hours total time on the Hobbs meter. In my last flight this year, I hit 1000 landings! My total Pilot-In-Command time stands at 775.6 hours, and I ended the year with 500.1 hours of Cross Country flying time.

This year we again did the long trip to Oshkosh. We also made it out to Salt Lake City four times to visit our daughter and to deal with some more home improvement and plumbing issues with the rental house there. I had some minor ignition issues that were bugging me, and the airplane had a lengthy annual this year. I also had to deal with a stuck exhaust valve, and the airplane was down for almost a month while I worked on that. I also updated my ADS-B unit, and I had to replace a failed autopilot servo. That downtime put a bit of a damper on the flying hours. I also spent a lot of my spare time this year dealing with a major project at our house involving landscaping our yard. We didn’t really have any free weekends to do some of the trips we had hoped to take this year.

Even the many local flights for breakfast/lunch were mostly to the same old places. We did start out the year going to Lake Havasu and Hangar 24 Brewing with the RV gang. I also was able to finally do a flight out to Aqua Caliente to soak in the hot springs there (highly recommended). I attended the Mojave Experimental Fly-In and was awarded the “Best Build” trophy!

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I also showed the airplane at the Ramona Air-Fair and Fly-In and got written up in the local newspaper.

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I did get to fly with 6 new people in the airplane for their first rides, and I hit 7 new airports. I ended up the year with a trip out to Yuma, AZ to meet up with some of my Dad’s cousins whom I hadn’t seen in 49 years. Here’s to more flying fun in 2019! Happy New Year.

Non-Annual Maintenance

After the big trip to Oshkosh we really haven’t been doing a whole lot of flying lately. We did fly out to Salt Lake City to visit Marissa over Labor Day weekend, and then I ended up back there in the beginning of October. Our rental house there had a water pipe burst and flood the basement with a foot of water. I was able to take off Monday afternoon and get out there in about 3:35 with a nice tailwind. After dealing with water damage companies, plumbers and insurance, I was able to find a weather window on Friday afternoon to head back home.

On the flight back, I had an anomaly with the autopilot Roll servo going offline, and then later getting a Skyview secondary network failure. All of this came and went by itself. After it cleared itself, I was able to use the Autopilot normally. About 30 minutes into the flight, my Primary Flight Display on the Skyview EFIS went blank. The engine and map pages were still up and running. The alert was an ADAHRS FAIL and another secondary network failure. After about 30 seconds, it all came back and was fine for the rest of the flight home.

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Not what you want to see as you are flying.

The weather during the week I was in Utah was rainy and the airplane was tied down outside. I wondered if it could be due to wetness, but I had the canopy covered and it wasn’t wet inside the fuselage.

The next day was the Ramona Air Fair. I was scheduled to fly Young Eagles for EAA Chapter 14. When I got to the airport Saturday morning it was very low IFR conditions and the weather report said that it might clear by 11am. I pulled the airplane out of the hangar and started it up to taxi over to the fuel island. I was low on fuel after the non-stop flight back from Utah. The engine fired right up, but then it really started running roughly. I played with the mixture, thinking it might be a fouled spark plug, and switched the P-Mags from Left to Right and back to Both which made no difference. The CHT/EGT gauge showed that cylinder 3 wasn’t coming up to temps. Then just as fast as it came on, it was back running smoothly and the temps came up. I taxied down to the ramp by the Tower where the Air Fair was going on. There were just a few planes there due to the weather, and I ended up hanging out at the airplane all day talking to people. The weather never really cleared up to more than Marginal VFR. I wasn’t going to fly any Young Eagles unless it was clear VFR weather. No fun to do scud running with other people’s children. Photos from the day are here.

The engine ran fine as I taxied back to the hangar. The next Monday I had to fly up to Fullerton, CA to pick up a friend of my daughter, who was visiting. I fired up the engine and it did just a bit of the same rough running with cylinder #3 showing coolness, then back to running smoothly and warming up. I have to admit a dilemma here on whether to scrub the flight or not. I let the engine warm up, and did a thorough preflight run up or two and everything was running fine. OK, let’s go. The flight up and back was uneventful, with no autopilot or engine issues.

Back home I got down to searching online to see what might be going on with the autopilot and the engine. The consensus on the engine was probably a sticky exhaust valve. Van’s Airforce Forums has plenty of information about how to cure this. There is an excellent writeup by Mike Bullock on how he went through this and was able to ream out the carbon buildup from the valve guide and get the engine running smoothly again.

In order to get access to the valve, you have to compress the valve springs. This requires a special tool, which isn’t cheap. Mike modified a couple of pry bars to make his own home-built valve spring compression tool. I went off to Home Depot and got my own pair of pry bars for less than $15, and went to grinding away various bits to make it work.

I spent all of the next weekend working on the sticky valve. It was definitely stuck. I won’t bore you here with the process, so if you are interested, read Mike’s post above in the link. I did go through all of the cylinders to see if any others were sticky, but they were all smooth. I had to drop the exhaust pipes for access inside the cylinder heads. It took a few days before I could put everything back together since I was short a few lock washers required on the exhaust nuts.

As the plane was just sitting in the hangar, the autopilot roll servo must have just locked itself up without any power on. I noticed this as I was walking around the airplane and I touched the aileron and found it completely stuck in position. I wiggled the aileron and it gave a quite a bit of resistance, until it “popped” and then it was smooth again. Again, back home and searching the internet I determined that it was probably the “shear screw” in the autopilot servo that “popped”. The shear screw is there to break in case the autopilot ever gets stuck. You can overwhelm the autopilot with the stick and shear this little brass screw to regain manual control if needed.

I powered up the Skyview system and went into the Setup and Systems menus to get to the autopilot hardware calibration screen. Moving the stick around showed the pitch servo coordinates moving around, but nothing for the roll servo coordinates. Time to extract the servo from the right wing.

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Autopilot Roll servo extracted from the wing.

The servo motor was completely locked up and the shear screw was definitely broken. Very strange to have the motor just lock up and I was very glad this didn’t happen while flying. I called up Dynon the next morning and got an RMA number to send the servo back for a rebuild. Since it was long out of warranty, they will rebuild it for a flat fee of $175. From looking online at the Dynon Forums, other people have had this happen, and it looks like the servo might have caused the issue with the secondary network and the previous ADAHRS FAIL issue. The Autopilot servos are also on the same network. The network has a redundant pair of network wires, so there is a primary and secondary path for the network.

The other thing going on with the airplane is an update to the ADS-B unit. Dynon originally provided an ADS-B unit SV-ADSB-470 which had just weather and traffic input from ground stations. They later came out with an updated unit SV-ADSB-472 which also can get traffic input from other ADS-B equipped aircraft without needing proximity to a ground station. The initial 470 units from Dynon had some limitations, and this was going to be fixed with the 472 units. Dynon announced back in early 2017 that they would have a trade in program for owners of the 470 units. However, the early 472 units had some hardware issues. Here we are a year and a half later and the updated 472 units are fixed now and back shipping. Dynon called me this week and asked if I still wanted to trade-in the old for the new unit. I said yes, so they are charging me $308 for the new unit (saving $500 for the cost of a new unit) and I have to mail them back the old unit within 30 days. Now I get to crawl back into the rear fuselage and swap out these units.

Lastly, since the airplane is grounded, I might as well also get my new tires mounted. The front nose wheel steering break out forces also seems to have gone up recently, so I need to take that all apart and get it re-lubed up and the force on the fork set correctly.

I also dropped off the Oxygen tank for a refill. We went through most of the O2 on the trips to and from Utah. The second trip out there I was up high at 15,500′ getting pushed along by some strong tailwinds. You can’t do that high flying without supplemental oxygen.

I’m hoping to be back flying again soon! I’ve got a few trips planned in the coming months.

EAA Airventure Oshkosh 2018

We made the pilgrimage again this year to the biggest aviation event in the world, EAA’s Airventure in Oshkosh, Wisconsin. This was my third time visiting, so I had a bit more knowledge about the event and what I wanted to do once I got there. My son Alex went along this year and we tent camped in HomeBuilt Camping.

Getting Ready

The week leading up to the trip was a bit stressful. I have been having some little issues with the ignition on the airplane. The P-mags were both just overhauled and updated at the annual condition inspection in June, but after putting them back on there were some little issues I had to work through. I have the Electronic Ignition Commander display, so I was able to cure the first issue pretty easily. The P-mags came back from the factory set to the most advanced timing settings of 40 degrees, which caused my cylinder temps to get very hot. I figured out that one and pushed them a different timing curve more suited to my engine. I thought it all was good after that, but I was still getting this ever so slight stutter occasionally. The EIC unit was also showing some timing divergence between the left and right P-mags. There is a nice bright red LED that blinks when that happens, so it definitely gets your attention. I flew on the Monday night before our departure to do an inflight Lean of Peak ignition stress test, Mag check and induction leak check. Everything seemed OK, except for cylinder #1’s EGT was quite a bit higher on one P-mag. This means I have a weak spark on that mag and plug. I wasn’t sure exactly why it is happening, but I did take off the P-mags to inspect them, and re-time them, and make sure all of the wires are in good shape. During this process I found one of the spark plug connectors was just a bit loose (on cylinder #1). Turns out one of the spark plug wire terminal clips was broken.

This was finally found on the Thursday night before we left on Saturday. I had bought a new plug for the one cylinder that was suspect (I love having all of the data from the EFIS display to point you directly to the problem cylinder), but it wasn’t the plug, but the connection to the plug wire. I had bought a spare spark plug terminal and boot during my annual inspection, so I was able to pop off the broken clip and get the spare one on. After that, the engine was back to running smoothly. However, I was still seeing a random bit of divergence when I did a ground run up of the engine. The timing advance on one P-mag will be different from the other P-mag and the divergence alarm can still pop up. On Friday, I flew over to Gillespie Field to fill up the fuel tanks, and to just see if the ignition was behaving. Thankfully, it was OK and I figured the problems were behind me. Also a big shout out and thank you to Bill Repucci of EIC who worked with me over the phone several nights in a row to troubleshoot all of the ignition issues.

Saturday – Departure Day

The plan was to depart Saturday morning at dawn and head to Ankeny, Iowa for the first night. The weather forecast looked like there might be some lingering thunderstorms over the Arizona desert, and there was. We loaded up the airplane with all of the camping gear and our bags. I had weighed everything beforehand and we ended up having to leave behind our two folding chairs (15 pounds too heavy).

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The dreaded “patchy fog” didn’t show up this morning.

We took off around 6:15am and once in the air we could see on the ADS-B weather display that it looked clearer to the north of Arizona, so we headed towards Lake Havasu then turned east. We got just a touch of rain on us at Havasu. Somewhere west of Flagstaff on the emergency guard frequency 121.5 (always good to monitor that) we heard an Emergency Locator Transponder going off. I contacted Prescott Flight Service and let them know. We were able to fly directly over Meteor Crater, then we landed in Holbrook, Arizona for our first fuel stop.

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Meteor Crater in Arizona.

Our next leg took us across New Mexico between Santa Fe and Albuquerque. We landed in Dumas, Texas where it was 101 degrees. We filled up our bellies with some good BBQ from the restaurant on the airport, and gassed up for the next leg. On both of these long legs the airplane was purring just fine and no timing issues at all. We cut across the panhandle of Oklahoma and then Kansas towards Iowa. We did our third fuel stop at Clarinda, Iowa. All the way the skies were clear and we got to Ankeny in the early evening. The hotel is just a short walk from the airport, and we went over to the nearby Outback Steakhouse restaurant for some good food and drinks.

To Oshkosh, or not to Oshkosh?

The forecast for Sunday in Iowa was clear, but to the east in Wisconsin it was low overcast and Oshkosh was probably going to be IFR until noon. We walked over to a nearby IHOP in the morning, had breakfast, and did a late checkout from the hotel at noon. We headed back to the airport and took off for Wisconsin around 1pm, figuring we would be in Oshkosh by 3pm and the weather would be clear there. It was, but I think everyone else flying in had the same idea. As we flew east the cloud layers started showing up and we descended underneath them. We landed at Boscobel, Wisconsin to top off the fuel for our last leg into Oshkosh. About 40 miles out we could just start to pick up the Oshkosh ATIS and arrival information, along with the Approach controller frequency for Ripon and Fisk, which are the waypoints for the VFR arrivals.

As we got closer we started seeing lots and lots of airplanes all heading to Ripon. The controllers were overwhelmed and they really were only letting a trickle of airplanes into the field for some reason. We could see on the EFIS traffic display literally hundreds of airplanes all circling the approach area. Not Good. We could hear the controllers just telling every to line up a mile (or two) in trail. Within 2 miles of us, there were probably over a dozen airplanes! That’s not going to work well. We decided to stay away from this mess and we ended up circling the Green Lake hold 3 times. At this point we had been up for well over an hour of circling and by doing the math we could see that the mess was just getting worse and worse. It would just be dumb luck to get through Ripon to Fisk to Oshkosh for landing. I punched in the nearest airports on the GPS and we diverted to Wautoma. Better to be on the ground and safe than to have a mid-air collision. We definitely came way too close to other airplanes circling in the Green Lake hold. It looked worse on the screen farther ahead. Lots of tempers were flaring on the radio with people getting cut off and other stupid pilot tricks like going the wrong way in the holds.

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Maybe we should rethink this arrival to Oshkosh. Notice that there are two lakes on the map. The top one is Rush Lake and there should be a ring of airplanes going around it. The bottom one is Green Lake and it also should have a ring of airplanes circling it (according to the FAA NOTAM). The FAA controllers dropped the ball on this big time by just telling everyone between Ripon and Fisk to “turn left” and try again.

The Wautoma airport had about 30 airplanes already down on the ramp, so we landed, taxied over and parked on the grass area by the fuel station. There were about 6 planes already in line for gas. We ended up just tying down, pitching the tent and spending the night there. We were able to get into the nearby town for some dinner, and we got to sit around and visit with all of the other refugees from Oshkosh. By 8pm there were at least 70 planes on the ground for the night. We could listen to the Fisk approach on liveatc.net, and watch the conga line of traffic on flightradar24.com safely from our smart phones. Landing away from Oshkosh meant we missed the HomeBuilt Camping Beer bash, but I was very glad to NOT be stressed about trying to get there. We were also able to eventually top off the fuel tanks later that evening, so in the morning we would have plenty of loiter time if needed. I figured it would probably be just as bad the next morning (it was).

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Waiting it out at Wautoma.

To Oshkosh, Take Two

We got up early, broke camp, packed up and were in the air before the 7am arrival opening at Oshkosh. This time we only got turned away once. We headed to Ripon, then over the railroad tracks to Fisk and the controllers again were overloaded and told everyone to “turn left” and go back to Ripon. Our second attempt again had us right over the train tracks, but there were airplanes both right and left of us. Some high, some low. You are supposed to be directly over the railroad tracks at 1800′ and going 90 knots. I stuck to this track and ended up getting past a trio of slower and lower Cubs that were too low and off to the left side of us, then we pulled away from a slow going low-wing airplane that was high and to the right of us. Next thing I know, we are over Fisk and we have good spacing back from the airplane directly out in front of us. Rock the wings and welcome to Oshkosh for landing on Runway 27’s green dot. We made it finally!

Alex made a YouTube video of our arrival attempts.

Opening Day

The next several hours on Monday were spent tying down the airplane, unloading everything, setting up camp, and getting registered. We ended up at the very south end of the HomeBuilt Camping area, where we were at least closer to the show center. We got some lunch and wandered around various exhibit halls looking for some good swag. We were just checking out the Boeing Plaza area when we ran into my niece’s husband, (actor/comedian Johnny Pemberton) and his brother and Dad. Amazing that with tens of thousands of people over acres and acres that we would accidentally bump into them.

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Alex, Bruce, and Johnny Pemberton (my niece’s husband) who drove into Oshkosh for the day with his brother and Dad.

They just were there for the day and they wanted to come see my airplane later. That afternoon we hopped on the trams and went all the way to the South 40, then all the way back to the home built area. We met up again at our camp and they got to take a look at the purple RV. Monday night is the RV beer bash, so we spent some hours there talking to all of the RV folks.

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The RV Beer Bash was packed with people.

At 8pm we left the beer bash and walked back up to Boeing Plaza where the opening night concert was just finishing. We walked over to the Balloon glow and took some pictures of the show planes along the flight line.

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Balloons getting fired up.

Tuesday

We hit some more exhibit halls and wandered around more of the show. We decided to take the Warbird Tram tour, which was great. They drive you out and about in the Warbirds area and talk about all of the different types of airplanes there. From there we hit the Homebuilt area and Alex got to sit in the RV-14A. Yes, it has more leg room and shoulder space than the RV-9A, but I’m not going to start building one any time soon.

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The Warbirds ramp.

Tuesday evening was the RivetBangers.com dinner event at the Black Otter Supper Club where the 32oz Prime Rib is the small cut. Always a good time, and we took back plenty of leftovers.

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Epic Prime Rib. This is the smallest cut at 2 pounds.

Wednesday

We walked around in the NASA pavilion and also hit up the Innovations area. After that we again walked around the Boeing Plaza and decided to spend some time in the Vintage area. We lined up for the Vintage Tram tour and were first in line waiting in the shade when the tram arrived, by the time we walked the 10 feet to the tram it was completely full! We ended up just walking around the area looking at all of the cool Biplanes. Where else would you see a dozen Staggerwing Beechcrafts lined up in a row?

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One of the prettiest airplanes ever made, the Beech Staggerwing.

They also had a nice selection of WWI aircraft to celebrate the 100 years since the war. We also walked the flight line and saw all of the aerobatic planes at the IAC headquarters. There were just so many airplanes to look at, it was hard to not be overloaded with aviation. We ended up back at our airplane for the afternoon airshow and took some shade under the wing and watched. Alex had a headache, so he decided he didn’t want to go to the Young Eagles awards ceremony and dinner event at the Museum. I ended up going over there by myself (free meal!). I sat down at a table with some other YE volunteers and got to see Jeff Skiles, Sean D. Tucker and Jack Pelton give out some awards. I left there after the ceremonies and headed back to the flight line for the evening airshow. The weather was looking like it was going to rain and it did right as the show started. There was a big thunderstorm headed to Oshkosh, so they canceled the night airshow. We ended up back at the HBC pavilion and did some beer drinking while the rain really came down. Thankfully, it let up a bit and we were able to get back to the tent before the next cell hit the area. It got really windy and then the rain really started coming down. The tent held up fine and we stayed dry.

Thursday

The weather the next morning was clear, but everything outside was drenched. I had put the travel cover on the airplane to keep the rain from getting inside. It held up and kept the electronics dry. Alex and I decided to head out to the Museum and Pioneer Airport where they have the helicopter rides. We got in line, paid our $49 and got to go up in a Bell 47 helicopter. They take a route over the grounds that lasts maybe 8 minutes, but it is well worth it to look down and see everything. The campgrounds are just huge where all of the non-fly-in campers stay during the week.

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Camp Scholler at Airventure.

After the helicopter ride, we did a quick pass through the EAA Museum. We hit some of the last remaining exhibit areas that we hadn’t been to yet. I went over to the FAA display and was able to get them to pull up my ADS-B compliance report (which was acceptable). I’m now good for the 2020 deadline to be in compliance. We did some last minute shopping for souvenirs and also did another pass of the One Week Wonder RV-12 build. We got there just a bit too late to pull a rivet on the wings. On the way back to the campsite, we took a look at the Bally Bomber. This is a 1/3 scale B-17 that can be piloted by a single person. Scratch built, it took the builder decades to complete.

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The Bally Bomber had to be the most unique airplane on the entire field.

The UCAP podcast tie down party was over by the North 40, so we got on the bus to take us over there. We had some beers and talked with some other folks and Dave Higdon, who is one of the podcasters. We were hungry so we walked across the street from the airport and found a Mexican restaurant for dinner.

Friday

Time to pack up and head home!

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We got the camping gear all packed up, and checked out from the HBC. The weather was looking VFR, but there were some lingering low clouds over Wisconsin until we got more to the west. We got in the conga line to depart and took off on Runway 36 without too much delay. Our first gas stop was Mauston – New Lisbon, Wisconsin. After that we were able to get above the scattered clouds and we made it all the way across Minnesota and landed in Yankton, South Dakota. The EAA chapter in Yankton had a nice lunch spread for pilots, so we donated some dollars and filled up on hot dogs, chips, soda and desert.

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Getting fueled up and having some lunch in Yankton, SD.

The next leg was a long one. We left Yankton as the thunderstorms were starting to pop up over South Dakota and Nebraska. We diverted just a bit to the north and went around the main cells that were between us and Wyoming. The skies became much clearer as we headed west. We crossed the Rockies in Wyoming and we headed towards Casper with a nice tailwind (the only time we had one). From Casper we turned towards Rock Springs and it got pretty bumpy on this leg. We got tossed about for an hour or so. Anytime the autopilot can’t handle the airplane, you know it is pretty rough. We landed at Rock Springs and filled up again with gas. The winds were better on the next leg as we headed towards Salt Lake City for our overnight stop. We landed in Bountiful, Utah and Marissa came over to pick us up. We had a nice dinner and spent the night at her house.

Saturday

I got up early on Saturday before it got too hot outside and did some yard work on the rental house by trimming some bushes and pulling all of the weeds. I guess this means I can write off this trip for tax purposes!

We had breakfast, then headed for the airport around 10:30am. The clouds were again starting to build up some thunderstorms, and we dodged a few of them in central Utah. Once we got over the Nevada desert the clouds disappeared, but we fought some strong headwinds the entire way home. It took us 4.4 hours on this leg from Bountiful to Ramona. We were back at the airport and in the hangar by 3pm.

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Back in Ramona after 28 hours of flying.

Another Oshkosh trip complete!

Hundreds of photos were taken by Alex and me and they are in this gallery.

 

 

 

 

Black Box Data

You’ve heard of the “black box” in all of the Commercial airliners. It is there to record all of the flight parameters so in the event of an accident or incident, the investigators can get a clear picture of what actually happened. Today’s modern electronic flight information systems (EFIS) do much of this same functionality. The EFIS records numerous data parameters during every flight. Then the recorded data can be downloaded from the EFIS and examined. It sounds complicated, but it is very simple and easy to do.

The Dynon Skyview EFIS in my airplane can be configured to record at different rates. The data rate determines how much data it can store at any given time. The data rate can be anywhere from 16 times per second (16Hz) to every six seconds (.1Hz). The faster the data recording frequency, the less time your recording will cover but the granularity is maximized. The EFIS will always record the most recent 15 minutes at the higher frequency. For most flights I leave the data rate at a lower rate, just so I don’t have to download the data after every flight. Most of the parameters being recorded do not change at a high enough rate to warrant the faster recording frequency. For example, your outside air temperature (OAT) isn’t going to be changing degrees multiple times per second. You might see the OAT change a few degrees in several minutes. For flight testing, you can increase the recording rate to get more data points per second.

So what sort of parameters are recorded? It depends on your EFIS, and what signals you pass to it. For example, the most common ones are the temperatures of the cylinder heads, exhaust gases, oil, outside air, pressures of the fuel and oil, rates of climb, altitude, voltage, amperage, heading, engine RPM, etc. Some of the parameters are less interesting, such as the canopy latch status and parking brake setting, but if there was an accident, something like this might be relevant.

The data rate (approximately once per second) I have set for N5771H gives me almost 8 hours of flight data, which takes up about 60Mb and includes 60+ flight data parameters. All I have to do is remember to download the data to a USB drive. On the Dynon Skyview, you hold down two buttons (the rightmost 2 buttons simultaneously) to get to the SETUP page, then select EXPORT USER DATA LOGS. It takes less than a minute. Unplug the USB stick and now you have your data ready to import on your PC.

Now that you have this data, what do you do with it? The raw data on the USB stick is all comma separated values (CSV format) lines of data, and is very hard to understand in that format. Here is where “Big Data” comes to the rescue. There is a terrific online site, savvyanalysis.com, that will let you upload and store your data for free. They provide a web page that allows you to select which parameters you want to examine and they draw this up in graphical format. The data that you add to the site adds to their database of flight data, and some of the insights that are derived from this large pool of data are fascinating. The proprietor of Savvy Analysis, Mike Busch, gave a seminar (part 1 and part 2 are on EAA’s webinar site) last year here in San Diego that I attended. He talked at length about the millions of flights they now store in their database, and what sort of information they can glean from it. For a particular airplane like the Cirrus SR-22, or a Cessna 172, they can see things like the average temperature spreads across the cylinders, or what fuel flows are for cruise, etc. He said that the CHT spread on the Cessna, which was designed before fancy computers could do airflow simulations was not as tight as the new Cirrus airplanes. For additional fees, they will grade your airplane’s operation and how you are managing these parameters compared to other similar aircraft. They also can diagnose problems remotely just from looking at the data you upload for your airplane. You might have a clogged fuel injector, or a bad spark plug and this data will pinpoint exactly what might be the cause of a rough running engine. They can even see from the data if you have a valve ready to fail!

The EFIS data is also something that the manufacturer of the unit might want to see to troubleshoot a product issue. I know that Dynon has in the past has had software issues that could be diagnosed by looking at the EFIS data that is recorded. They also save some “black-box” data that is only useful to the manufacturer.

In my early flights of N5771H before the engine rings were fully broken in, I did a mag-check and had a very rough engine on one mag. It was definitely a fouled plug, because I could see that a particular cylinder’s EGT was going hotter. I headed back to the hangar and knew exactly which spark plug to pull out and clean. I put it back in and was able to fly without issues.

If you want to see ALL of my flight data, its available here. Click on a flight, then you can see the EGT and CHT data by default. If you look on the right side of the graph, you will see a box with “None” next to both the top and bottom graphs. You can use the pull down menu in the box to select other parameters to graph. It will overlay another parameter from the data on to the EGT or CHT graph. You can overlay 4 parameters on a page. I usually look at PALT (Pressure Altitude) which show my climbs and descents, and FF (Fuel Flow). You can see when the PALT rises, that is my take-off, then the FF will go down as I lean the engine. Other interesting parameters to graph are the TAS (True Air Speed), VERT_SPEED (vertical speed) and Percent Power. You can do the same selection on the EGT and CHT pull down boxes on the left side of the graphs to compare any 4 data variables. For each flight, there is also a “Show Flight Map” link at the bottom and this brings up a map with the GPS latitude/longitude coordinates on a map showing exactly where I’ve flown.

It is always good to look over the data after a long cross country flight and see if anything was out of normal ranges. Welcome to the future of BIG DATA in aviation.