Flights #27 through #32
Conducted 4/27/2013 -
The Big Push. On a day forecasted to be perfectly clear, with just 8 hours
of testing to finish, we decided we would try our best to complete Phase one
testing that day. Fitting 8 hours of flying into 14 hours of daylight
might not seem like a tough task, but when those 8 hours are in ~1.5 hour chunks
with reballasting and refueling in between, the task gets tougher. To
accomplish this each of us had a significant part to play. John, as test
pilot, was responsible for ensuring that each flight was conducted safely, and
in accordance with the flight test plan. Christine was to coordinate the
ground operations so that as soon as the plane landed any additional ballast
needed for next flight was ready, and the line guys were ready to refuel the
plane. Ella, was to take the responsibility of maintaining radio
communication with John when Christine was not able to. Ella would then
relay messages if needed. For the most part, the day went like clockwork,
and it ended in celebration.
John's flight report to the Cozy list is below:
"The weather held perfect for all day Saturday, and we were back at the airport
at 6:30am. We had already re-ballasted the plane for the next test before
leaving the night before, so it was just a matter of pushing the plane out,
preflighting, and getting right back to work with climb/descent testing. After
each test, I would land, re-ballast (which sometimes required more fuel), then
head back up for another round. I figured if I didn’t waste time, I might be
able to make it through the rest of the tests by the time the sun set.
As it turned out, Summer fell on a Saturday here in Minnesota. We went from
30-40s all April to a high of 74 on Saturday. While, it was very nice to finally
be flying without a parka again, it brought back one other little issue…Ground
cooling. As the temps warmed up in the afternoon, the 30 minutes between landing
and the next take off were not enough to allow the oil temps to drop
sufficiently. My last flight before stopping for lunch, the oil temp was 179F at
start up and 200F at take off. I only climbed to 4K’ MSL (3K’ AGL) on the
initial climb, but the oil temp rose to 235F in that short 2 minutes. As I
conducted the next climb tests I did learn a bit of useful information without
even looking at the EFIS logs. My normal climb out is 120Kts, but the oil temps
don’t seem to rise a whole lot faster if I climb at 85kts. The plane climbs much
faster at 85Kts though, so I’m able to get to a given altitude with lower oil
temps. The downside is that I can’t see anything ahead of me. The CHTs didn’t
seem to differ much on the climb speed either. They were only slightly higher at
increased climb angles. My hottest cylinder (#2) never exceeded 420F at any
point in the testing, the others never exceeded 380F. In cruise #2 runs about
365F compared to the 280-290F of the others, so I apparently have a little
airflow balancing to do yet.
After completing the climb and descent testing at the various weight and CG
locations, The last test to conduct was flutter testing. Initially that test
didn’t scare me. I knew my control surfaces were balanced. I checked them only a
few dozen times during the build. I also knew there was no slop in the controls.
If anything my controls were a little stiff in pitch due to the pitch trim
system. But in discussion with various other folks I became more and more
worried about it. My DAR offered to lend me his parachute, and I decided that
would make me feel better. At least if I wore a chute, I would likely not need
it, so the superstitious side of me said to wear one.
When I went through the flutter testing in the sim, the realization of what it
would feel like was clearly not present. I conducted the tests between 7500’ and
8500’ MSL, all the way to 200Kts IAS. Smacking the stick or jabbing the rudder
at those speeds unsettles both the plane AND my stomach. Pitch was probably the
worst. I usually LOVE roller coasters, but having my stomach jump to my throat
or my butt is NOT a feeling I enjoyed, however brief, while flying my plane.
The good news is that there was no flutter at any speed. Once the flutter
testing was complete I looked at the flight timer, I was less than .2 hours from
the 40 hour mark. I flipped on some music, and just cruised around bit letting
the realization set in that when I landed the plane I would be one log book
entry away from the adventure of building an airplane giving birth to many, many
more adventures."