Friday, August 19, 2022

8/19/2022 Update

 


I bought a new tube for the copilot main side since I'd put Dynabeads in it and was skeptical that they would function as intended with the butyl compound causing the beads to clump.  The date on the old tube was 2/14/13.   The bearing was loose enough, the seal was rotating with the wheel indicating the axle nut was not tight enough.   The pilot side was okay.  I reassembled the wheel with the new tube and tightened the axle nut enough to keep the seal from spinning with the wheel.

I posted a YouTube video of landing at MWL, 7 knot crosswind, deploying the landing brake in ground effect.  This is my 17th landing.  Almost 18 hours on the Cozy now.

https://youtu.be/zKuOIKjpXFA

Thursday, August 18, 2022

8/18/2022 Update - Nose gear preload and nose wheel bearing preload.

 I checked the nose gear preload and found it took 9 .lbs at the axle to swing the wheel.  I backed the nut off 30 degrees and it measured 4.5 .lbs which is what the POH specifies.

Spinning the nose wheel, the wheel bearing seal was rotating with the wheel indicating it's preload is inadequate.  It had been checked before first flight.  The axle nut is tight so will be necessary to shave off a few thousandths on the inside surface of one or both of the spacers.  Seems like maybe Loctite 680 (for assembly of circular components) applied to the spacer/bearing contact would be a good solution here too.

Tuesday, August 16, 2022

08/16/2022 Update

 Flew 2.5 hours today, just .2 shy of 18 hours total now.  First leg from T67 to MWL to get 10 gallons of fuel @ $5.40/gallon and to use the compass rose to ground calibrate the magnetometer after moving it to the nose.  I decided that the right roll isn't to bad and can be trimmed out.  I was high approaching MWL so did a descending 360 to enter the pattern for 13.  Wind was almost a direct crosswind at 7 knots.  I've tended to land to the left of the center line in crosswinds from the right.

Departed MWL towards XBP and flew at about 5500' to do the in air calibration of the compass.  The first 360, calibration made it over 40 on the quality number, then the next 360 in the opposite direction seemed to go down in quality.  Then I flew West for about a mile and the quality went over 100 and green.  Hit finish and save.  Exited back to the map display, accessed the Auto Pilot through the panel (it's in the basic mode and the panel buttons don't work in basic mode).  I selected Track and Altitude mode, dialed in 270 and the AP stabilized the altitude and heading.   Changed the heading to N, E, & S and the AP acquired each heading successfully.  There was a lot of traffic near XBP so I flew back to MWL and over to Possum Kingdom, Grayson.  Practiced some slow flight and approached Mineral Wells.  The ATIS was reporting almost constant wind changes.   As I approached most traffic was using 31 but the wind changed and a Baron announced they'd land on 13.  I announced I was going to do a 360 West of the field, join the downwind and got a radio call they couldn't see me on ADSB.  My transponder had been in STBY since I'd left T67.   Ooops.   I'd thought I'd gotten the settings correct to automatically switch the transponder on so will need to read the manual and explore the settings some more.  Also add "check transponder" to the pre-take off and in-flight check lists.  When I returned to T67 I followed a student and CFI in a C150, they flew a huge pattern and since I was following them, also had to fly a huge pattern.   I just can't help but think if either their engine or mine quits, we're landing at Walmart.   My wife informed me of her displeasure that I wasn't showing on the maps.  When I pulled the plane into the hangar and was doing post flight checks, found the copilot gas cap laying on the strake.  Now I think I know what made a "tink tink" sound a couple of times on the way back, it was the anchor in the tank.  At least the fuel cap tether works. 

I pulled the cowls off and had some drops of oil in the bottom cowl and oil around the alternator and starter.  Appears the sump leak isn't stopped yet.  I have a plan to apply an ample amount of Loctite 290 to the four suspected bolt holes by making some plugs for the holes that go up from the bottom and stop shy of where the sump and case meet.  A neighbor stopped by and thinks he has a spare sump gasket I can have.  I may replace it during the next oil change if the Loctite doesn't fix it.

I've heard a little shimmy when touching down and suspect it's an unbalanced wheel causing it.  - Update, I tried to install Dynabeads in a main tire and found there's a dark grease-like compound in it.   The Leak Guard tires say they have a butyl rubber compound in them so the beads would probably clump up in the tubes.  I did get some installed in the nose wheel which at this time is a Kenda.  I do have an older Aeroclassic but was leery of running it since it's probably more than 10 years old.  Update-The front wheel spacers needed to be milled down a few thousandths to increase the preload on the wheel bearings. I checked with Russ and he advised he had similar experience.






Saturday, August 13, 2022

Tire bead balancing

 I've used ceramic tire balancing beads for years on my motorcycle and other vehicles.  I think they may help reduce nose wheel shimmy on the Cozy too.  There's a chart here for different sized tires and ounces of beads required for balancing.  I recall seeing where someone  made a dynamic prop balancer using beads but am unable to find the post now.  A post on the Vans forum confirmed that others are using beads and specified they had only used 1/2 .oz per tire to stop a shimmy.

https://innovativebalancing.com/trailerchart.htm


Update. I tried to install beads, but the beads clogged up in the valve stem.  I tried to use small gauge safety wire to help free the beads up and when I pulled it out, it had what looked like molybdenum grease on the wire.   

**Another update....I bought a new tube and cut the old tube open that I'd put the beads in and found the inside is coated with powder.  Apparently the inside of the valve stem is coated with something to prevent corrosion.   So if you can get the beads through the valve stem, they should work fine.  There was minimal clumping of beads that I was able to get through the stem.  I dumped them into a bowl and will get a photo of them posted.   I ended up buying new tires and tubes since the date on the tube is 2013 (almost 10 years old).  


Thursday, August 11, 2022

Update 8/11/2022

 Blue dye from 100 LL was appearing on the top of the injector bosses where the 90 degree elbows screw in.  I took the side cylinder baffling loose and removed the allen head screws that holds the top part of the boss down over the injectors, then removed the elbows, cleaned up the parts and reassembled with Permatex 56521 (recommended by Ross).  Red Loctite is applied to the small screw threads.  I ran the fuel pump and verified no leaks.

The lower cowl 60 degree ramp that diverts air for the #2 cylinder was trimmed by 1/4" in attempt to get some more air to it.  I think #4 is getting more of it's air.  The delta temp is 20-30 degrees rather than 50.

The ADAHRS was moved into the nose above the pilot's feet in order to get better magnetic isolation.  Still need to secure the network cable and OAT wires so they don't get snagged by the pilot's feet.

Installed Dynon WiFi dongles, configured and tested connectivity with my iPhone.

Next flight, need to quantify the right roll (if any) needs further action.  Possibly a Gurney flap may be in order since it would be easy to tweak.

I'm considering doing another W&B with fuel, oil and pilot to ensure the actual numbers are matching the spreadsheet and Dynon W&B calculator.   Previously, the stations, weight and CG seemed pretty close to the prototype POH.  The exact weight of the fuel and oil may be hard to get within 10 .lbs.  The nose is slightly above level so I need to get it level for the W&B test.





Tuesday, August 9, 2022

8/9/2022 Update

 Installed the new P255-150G-E4A sensors to replace the old Kavlico fuel and oil pressure sensors.

Applied Loctite 290 to 4 sump bolt holes above the intake.  Replaced a substandard 1/4 x 20 bolt that looked like it was self tapping and bent.

Began moving the ADAHRS from in front of the pilot to the nose area to resolve compass calibration issues.

Monday, August 8, 2022

8/8/2022 Update

 Flight test to check CHT cooling.   Take off roll was longer with 26 gallons of fuel.  Delta's are much better.  4 is coolest, 2 is hottest.

The in air compass calibration failed.  It's appearing that the remote magnetometer may need to be installed.

At 105 knots there's a slight squeal coming from somewhere.

The OAT at 8000' was 63F.   There's plenty of air blowing on my legs, probably coming from the cracks around the canard.

Fuel pressure dropped to zero at 53 minutes into testing so aborted testing and returned to T67.  While returning, the pressure then began reading high after it read zero for a period.  Engine was still running fine, temps good.  As I neared Copeland 4T2,  I opened the throttle and the engine ran at 2700 RPM.

The factors before the fuel pressure dropping is I was trimming for 70 KIAS @ 8000'.    I wasn't getting a canard bob at DA 10000.

The GoPro fell to the back seat floor again when turning down wind.  It makes a loud bang.  The Velcro needs some help or maybe some composite structure to grip the base.

Less than spectacular landing at T67.  Did a low pass, touch and go and then landed a little fast.  There was a crosswind and it was hot.

Need to remove the cowls, inspect for oil leaks, inspect fuel pressure sensor & wires.  Clean fuel filter, check oil.  Been using 1 qt/4 hours.  

Saturday, August 6, 2022

8/5/2022 Update

 Joined Russ's Zoom call Frodau night to hear about the Airventure Cup Race and Oshkosh experience.  Mark Reiger and Andrew Anunson are progressing with Phase I testing.  

Rough River and Kanab and other fly ins are coming up.

Watched a Flutter testing video.

"back to work"

Thursday, August 4, 2022

Update 8/4/2022

 Flight test after replacing Bowlus tape on the spar/strake gaps with HPVC foam and micro.  Also after installing ramps for 3 & 4, removing the 60 degree ramp..

The AP still needs dialed in but seems to work better.  I'm starting to get used to the pilot work saving flow of Skyview better but still need more experience.

The VSI graph looks noisy, but it was hot and bumpy.

Heard a Mayday at Bridgeport XBP.  A Warrior calling the Mayday landed with the wind, blocked the runway for awhile.  No injuries as far as I know.  Another reason to go to Mineral Wells for fuel.   Chatted with some fire bomber crew members that were grilling at the FBO.

I redid flight test 4 again.  The TAS appears to be very close at higher air speeds and is further off at low air speeds.

CHT's with the new ramps has #3 hottest, #4 next, then 2 and 1.  Analyzing data, it's appearing the earlier 60 degree ramp was better in several regards than the radiused ramps that should be better at pressure recovery.  Looks like if I set the 60 degree ramp further aft on the #3 side, should get more air onto 3.  

There was about 1/2 dozen drops of oil in the aft part of the lower cowl.  Minor seeps  are from two of the top 1/4" case bolts that are holding Adel clamps.   I've retorqued these previously, but they're persisting to leak, so I removed one at a time, cleaned out the oil, put some Loctite 290 in the holes.  I also found I hadn't put a flat washer under one of the Adel clamps, so added one and retorqued each bolt.  There is a little oil gathering around the aft part of the cold air sump.   I cleaned the oil off and applied some Loctite 290 to the edge of the gasket.  If this doesn't work, I'll remove each bolt, clean and apply Loctite to the holes, then replace the bolts.   I follow the torque specs and pattern in the engine manual for these 20 bolts.