Wendell Folks RV-8 Project - Page 80.
January 27, 2008: This Sunday afternoon had
wonderful weather considering how it has been for the past few weeks. We pulled the
RV-8 out in the sunshine to calibrate the magnetic sensors on the Dynon unit and calibrate
the wet compass on top of the instrument panel. The airplane had to be aligned on
the four cardinal points of the compass, 0/360, 90, 180, and 270 degrees. I walked
the concrete ramp to be sure my trusty oil-filled, hand-held compass would remain aligned
with the seams of the concrete pad in front of the shop where the airplane was built.
Wendell assured me there was no steel rebar or mesh in the slabs to distort the
magnetic field. He was right. We also leveled the airplane in both directions
before running each of the four calibration routines in the Dynon software. This is
the first alignment with magnetic north, which was about 10 degrees off from the alignment
of the seams and edges of the concrete slab in front of the hangar and shop/garage you see
in this picture.
Wendell as I got so busy doing each of the moves to the next heading, I forgot
to take the picture with the nose pointing to the East. This shot has the nose of
the airplane pointed South. Just in case you missed it in the first picture, take
note of the 3/4-inch board under the tire on this side and the wooden wheel chock.
The board leveled the airplane laterally. The steel drum with boards on it leveled
the longerons to represent level flight.
Wendell's friend "Cool" is helping with the oil drum and spacer
boards to get the longerons level at each of the four magnetic alignment positions.
My old Caddy and Cool's pickup are parked well away from the airplane to avoid any
magnetic disturbance near the airplane.
The upper set of spark plugs were removed to spin up the engine using only the
starter. The purpose was to get the oil circulating before the first engine start.
I made a check of the prop governor and a few other key oil locations to find no
leaks. After that was done, we put two gallons of 100LL AVGAS in each tank, then
tested the electric fuel pump and primer valve for fuel leaks. None were found there
Then it was time to push the fuel mixture to rich and go for the first engine
start. The engine came to life just after 4:30 PM. A quick check of the engine
monitor at 1000 RPM to see that all the EGT and CHT sensors were climbing to temps well
above ambient and then it was time to shut things down for one more cautionary check
around the engine. The oil pressure got above 65 PSI at 1000 RPM, and still no oil
After a successful first engine run, I told Wendell to crank it up again and
taxi over to the ramp in front of the hangar door.
And there it sits ready to go back into the hangar after the first engine test
and fuel system tests. By the way, the Dynon unit calibrated to within 1 degree of
the four cardinal magnetic bearings, but ONLY with the airplane leveled. Since the
only way a compass is reliable in flight is in straight and level conditions, we are
satisfied. We checked the Dynon and the wet compass with the tail wheel on the deck
and there was a variance from the "longerons level" positions that represent
level flight conditions.
This was a GOOD DAY for RV-building. The end is now in sight. The DAR told us he would be coming to see Wendell this week.
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