Tuesday, July 6, 2021

16 hours into Phase 1

Well in the past couple of weeks I have managed to get about 16 hours of flight time in on N88DA.  Since the engine is new I have had to do most of those at high power to ensure seating of the piston rings.  High power means lots of heat during the hottest months of the year including a few days of record breaking VERY high temps.  

A few squawks (issues) have come up as expected but so far nothing major.  

  • A 'buz' during high power operations at certain yaw orientations.  Turned out to be one of the skin panels near the copilot knee panel was "oil canning".  I fixed that with a little j-channel and some pro-seal.
  • Lots of mixture issues as I learn to use my new SDS EFI system.  This is just a learning curve and I'm slowly getting comfortable with what is required to fly this airplane and keep the engine CHT's down.
  • Trim indication was backward.  Easily fixed with a setting in the G3X touch settings.
  • Autopilot pitch trim as backward.  This was an interesting one...I enabled the Autopilot in "heading" mode and "Altitude" modes and the airplane immediately started to descend when it was supposed to climb.  Ooops.  The roll AP servo was also controlling the roll trim backward...again an easy fix.
  • CWS button does not seem to work.  Still haven't dug into that one.
  • A couple of oil leaks (seeps is probably more appropriate of a description).  Still working on those.
  • Oil pressure was still too high.  Had to adjust it a couple of times to get it where I wanted it.
  • Throttle position sensor failed at one point.  Not particularly important to safe engine operation but it does help with throttle response.  This one turned out to be a crimp issue where the heat shrink connectors I used didn't fare well between the two hot exhaust pipes.  I re-did the connection and then surrounded it with a heat protective cloth sleeve.
  • G3X EFIS would not update to the latest databases.  My fault...I had entered it on the Garmin site as a non touch G3X.  An email to Garmin support resolved that issue.
  • Com 2 does not transmit.  Another one that I am holding off on for now.  When I tried to do a transmit test with my Com 2 I was not getting a satisfactory return.  In addition if the engine was running it caused some electrical interference with my SDS-EFI system.  I'm pretty sure this is just a routing of the coax problem.  SDS is very clear in the instructions that it's wiring harness should be insulated by about 1" of air from other power source wires.  A coax during transmission is definitely a violation of that rule...if it turns out to be the case.  For now I have been operating with just one comm radio.
  • Fuel flow indication was WAY off.  A couple of re-fueling's and I think I have that number dialed in now.
I also did a couple of stalls to set my baseline stall speeds.  With the flaps up she stalls at 62 knots indicated and with the flaps down that number is 51 knots indicated.  Pretty close to the published numbers from Vans.

I still don't have the gear leg fairings or the wheel pants installed yet so I don't know the true performance.  I did find that at full throttle and 2700 RPM I was getting about 160knots true.  If the numbers pan out I expecting the same configuration with the fairings on will be about 175 knots true.

Oh, I mentioned heat... well the biggest issue I am dealing with right now is keeping the CHT's down and keeping the under cowl temps down.  On a couple of my flights the backup battery (under the cowl) was reporting excessive temps.  When I pulled the cowl this past weekend to do another routine inspection I found that the primary alternator ANL fuse holder had melted due to heat from both the exhaust as well as the heat generated from the electrical load.  I am going to try a couple of things to fix this.  For now I plan on installing a heat shield over the exhaust pipe on the right side.  If that doesn't completely resolve the issue my next step will be to move the backup battery, it's solenoid, and the cross connect solenoid to the tail cone next to the primary battery.  I may do this regardless of the outcome of the shielding simply because this airplane has turned out to be very nose heavy.  I'll know more when I do the W&B after installing all the interior pieces.

Overall I am very happy with how things are progressing.

Finally, I am excited to announce that I have moved N88DA to the Fall City airport!  I needed the longer/wider runway for my initial testing but now that I am comfortable with how the airplane is flying I figured it was time to move a little closer to home.

Sorry, I don't have any pictures to post this time.