Airworthiness Cert, Vortex Generators, Rigging Check, High speed taxi test

We finally received our airworthiness certificate on Aug 20, but had some work to do before first flight.  During our trip to Brasstown for transition training, our flight instructor (Vic) at Plane Fun Aircraft gave us many tips, and strongly recommended that we add vortex generators (VGs) before first flight.  These should lower stall speed a bit and they reportedly do not affect top speed.  We originally planned on adding them post flight to gauge their effectiveness, but changed our minds after talking to him.

The VGs that came with our kit had sharp corners and no adhesive (they recommended a form of super glue).  We elected to order some new ones (Stolspeed VGs) as these had a more rounded shape and came with 3M adhesive that is removable.  We installed them per instructions.  The VGs at the wing tips are installed with a closer spacing to ensure the wing tips stall after the root wing stalls.  We also installed VGs on the bottom of the horizontal stabilizers.

VGs on the wing

VGs on horizontal stabilizer

Also, even though our wings were rigged at the factory, we were advised to double check this   According to Vic, If the wing is leveled at the root, and measures something like -1 or -1.5 degree angle at the center (angle of incidence), then it should be about -2 to -3 degrees at the wing tip.  Having a little twist like helps ensure that the wing tips will stall after the main wing stalls. More important is to ensure that both wings are identical.  When we measured our wings, we found that the right wing was close to level across the whole span (no twist).  The left wing was a little better but had just -0.8 degrees at the tip.  We adjusted the right wing as far as allowed by loosening the jury strut and then rotating the main strut's clevis fork rod end, and were able to get it to -1.2 degrees at the tip (with about 0.6 degrees center).  The left wing was then adjusted to match this. 

We also ran another taxi test.  This time it was a higher speed taxi test down the runway.  Power was applied gradually while holding back the stick until the nose lifted off the ground, then reduced to hold the position.   The test went well, although we noted that the airspeed on our Garmin G3x never dropped under 23 MPH.  We contacted Garmin and found that this means we need to have our GSU25c (ADAHRS) replaced.  Luckily, this will be covered under warranty.  

We are also finding that our coolant temps still run a little high during taxi on hot days so we may need to adjust the cowling opening and/or radiator position sometime in the future to improve this.

Transition Training

 While waiting for our airworthiness inspection, we decided to get some transition training in a tri-gear Highlander.  We did this for 2 reasons... The primary reason was to get familiar with the airplane and stay safe, and the other was to appease the insurance gods that require some transition training before providing coverage.

We drove to Brasstown, NC to a build center for Just Highlanders called Plane Fun Aircraft.  Vic Payne was our flight instructor, who was outstanding.    The mornings were foggy, but it generally burned off somewhere between 10 or 11 am at which point we had beautiful flying weather.  We took turns flying and over the span of a couple days, we each received 5 hours of flight training.  Vic was not just a great flight instructor, but also a wealth of knowledge who gave us some excellent tips on rigging as well as suggestions on future potential plane modifications that might help with W&B, controls, or maintenance.  He also gave us some great tips on how to prepare for and fly initial test flights as he has done this on many many Highlanders.

Michael prepping for flight with Vic Payne

Ed starting his flight instruction with Vic

Airworthiness Inspection

We contacted our DAR, Lisa Burwell, early in the week to finish the airworthiness application and schedule the inspection.  A few days later, she called and said she had an opening on Fri, Aug 4, which we immediately agreed on.  The day before, we removed the cowling, turtledeck, footwell panels, and many inspection panels so that everything could be seen during the inspection.  

   She arrived with her husband, who is also an experienced A&P, and they both gave the plane a very thorough inspection.  Lisa also went over all the paperwork to ensure everything was in order.  They gave us a lot of great information and suggestions, and they did find a couple of nuts that were missing cotter pins, which was an easy fix.   Very happy with how the whole process worked and I can definitely recommend Lisa as a DAR.  We passed the inspection, and now have to wait for the FAA to process everything in order to get our airworthiness certification. 

Taxi test; coolant temp check, fuel system

Another taxi test was performed, this time watching the coolant temps closely since they were a bit high last time when running with the top cowl off.   This time, we kept the top cowl on to keep airflow as it would be during normal taxi, and the results were very good.  Coolant temps remained within the green. Outside temps were about 10 degrees cooler (87) than the last test, but coolant temps varied between 204 and 217 during taxi test which was over 35 degrees cooler than the last test. 

Michael checking coolant temps during taxi

Also, we double checked the fittings that were tightened last time (at bottom of left fuel tank, and at bottom of header tank).  No fuel seepage was detected so looks like these are now fixed.  

Lastly, we attached a small zippered plastic pouch to the left footwell panel which will hold our airplane registration and other documents that need to remain in the airplane.  Hours: 3