Saturday, June 18, 2016

Catching Up - Transport to Airport and More Issues (aka: fun)

After a nearly 4 month hiatus from documenting the project, it is way past time to catch up and let you know about the progress of N79AM.

She was transported to her new home, 27XS during the last week of March.  First shot below is load number one with one win, stabilator and rudder. Sufficiently padded, the trailer was pretty lightly loaded, but arrived without any injuries.


The loading of the fuselage was a challenge.  The main gear was too wide to fit on the trailer by about 3 inches, so I had to figure out a way to decrease the span.  The next few pictures show the convoluted process involved.  In the end, I started worrying about the rigidity of the assembly and the tendency to absorb road bumps.  We came up with some large foam pads from an old airbed that served to very nicely cushion the dollies on the mains.  The fuselage rode better than I could have hoped.  The thick foam worked beautifully.


A little detail of the main gear dolly.



Finally loaded and ready to depart from the home hangar to the real one, about 18 miles away.


One of the first tasks once in the hangar was to install the Warp Drive 3 blade prop. Initial layout and trial fitting reveals it is one fine piece of work.  It went together quickly and then was ready to attachment to the engine.




Below is a shot of the protractor-type device for setting a consistent pitch between each of the blades.


 Mounted the spinner and all is ready for more engine runs and eventually taxi testing prior to first flight.


I finally chose to install the fiberglass canopy trim piece and after much thought and debate, opted to use s structural silicone adhesive.  Eggenfellner had recommended the use of a very good Permatex product, The Right Stuff, but its cure time was way too short for the required task, so I found another competing product that cured in 2 hours, plus it had superior adhesive properties.  Pictures below show it drying under the pressure of painter's tape and a wratcheting strap.



One of the next issues to arise involved a fellow Viking-engined RV-12 whose newly flying craft experienced vapor lock on several occasions.  The builder had chosen to follow Eggenfellner's latest recommendations of mounting the fuel pumps on the engine side of the firewall.  (I have followed Mr. Eggenfellner's original recommendation of mounting the pumps in the tunnel between the pilot and passenger.)  After insulating the pumps in an aluminum box supplied with a blast tube, the vapor lock issue has been resolved for the other builder.

Knowing that the RV-12's tunnel absorbs a lot of heat from the engine, I took the precaution of installing a 200 CFM computer fan on the face panel of the tunnel to aid in pushing cool cabin air through the tunnel, in an attempt to keep those pumps nice and cool.  The poor quality of ethanol-based auto fuel results in a low boiling point, so vapor lock is a real possibility.

First picture below shows the installed fan in the face plate.

Another view of the backside of the installation.  The fan might be a bit of overkill for the intended task, as it pulls a hefty 2 amps.  I will monitor the fuel pumps temperature to see if I can downsize the fan.


The last installment of this blog will address a problem I experienced with my Dynon Skyview EFIS.  See the picture below.


This is a screen you don't really want to see.  It shows that the EFIS has self diagnosed a recurring problem, which it identifies as a System Event 5.  Apparently when the solid state hard drive inside the EFIS experiences a larger than usual (whatever that means) number of read/write errors, it is time to replace the unit.  To their credit, Dynon had me ship the unit (on my nickel) back to them for warranty repair at no cost.  I lost almost two weeks in the process, but I would hope that I have a newer, more reliable hard drive in the EFIS.

 Lastly, I'll toss in a few teaser shots of N79AM after final rigging and ready for some taxi tests.