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Just a suggestion: If your flight testing w/ the reduced ballast
goes well, consider using something useful as ballast. Lead
certainly is compact, but if you've got the space a well stocked
tool kit including a small sledge hammer for tie down stakes and a
selection of spares that could save the day on a trip (cowl
screws, nuts, bolts, screw clamps,oil, tires, inner tubes, etc.)
might be nice to have along someday.?? Also, again depending on
space available, an otherwise unnecessarily large battery
(automotive sealed AGM for instance) or a back up battery - both
largely lead anyway - could act as ballast that has usefulness
beyond its mass.
On 7/19/2019 2:39 PM, 'Marcus Borom'
Thanks to Marc (at least he spells
his name the same way as mine). Keith and Jay for
This is a great support group.
Based on the advice I have
received, I am considering testing the aircraft with a
reduction in the current nose ballast of 24.7 lbs to
10.7 lbs., instead of adding 10 to 25 lbs of
My nose ballast is currently
divided into two castings of 10.7 and 12.7 lbs.??
Removal of the 10.7 lb ballast will be a simple task..
I am attaching a revised
spreadsheet showing the changes in the CG for various
loadings.?? I also show the CG position for a full load
of fuel with no occupants.?? The nose will be very
light.?? If there are any warning signs here, I would
appreciate an alert.
Note to Jay;?? My 2004 A/C weight
was 1021.0 lbs and the weight in 2019 is 1030.9.?? My
adjusted nose ballast will bring them together again.
BTW.?? The 15 hours I mentioned was
between weighings.?? I have been flying my bird for 33
years ??? one crash at Oshkosh (1988 ??? see http://marc-borom.com
for details) and one mid-air collision (2017 ??? the
other guy was at fault).?? I am now a member of UFO
(Union of Flying Octogenarians).?? Looks like I am
going to have to install ADS-B In/Out for 2020.
How much did the basic weight
change after 15 years? More a curiosity, as where I
work we redo WB after any major maintenance and often
times at time intervals as well. It???s was a bit
shocking the first time you realize an aircraft can
pick up several hundred pounds in dirt and grime over
24 months in all the nooks and crannies.??
??Do I want to favor the nose ballast that
places the CG in the first flight box?
Keith Spreuer wrote:
opinion is that it is best to fly at the aft
limit as much as possible. That of course is
assuming you did thorough after CG testing
to be sure you have a deep stall margin.
agree 100% with Keith here. And I'll expand
on this a bit.
I don't quite understand whether the 23.4
lb. of ballast is already included in the
calcs you show or not, but as long as YOU
know whether it's part of the CG calcs,
that's all that matters.
for EZ type aircraft that are not
considerably overpowered (VE's with O-320's,
Berkuts with O-540's, etc.) for the original
design of the airfoil combination, you
almost always want to operate at the aftmost
CG in the acceptable range, as this will
minimize trim drag, lower takeoff and
landing speeds, and maximize cruise speed,
while still protecting from deep stall and
you have an O-235 or O-320 Long-EZ, you will
want to operate it at the rearmost CG
position of 103" (NOT 104" - the rear limit
was changed in the CP's at some point). This
assumes, as Keith wrote, that you have
TESTED the airplane to that CG position for
stability and stall, per the Phase I
should ballast the plane (either with or
without the existing 23.4 lb, or part of it)
so that with YOU in the front seat and full
fuel (fuel's at 104", so full fuel will be
the rearmost CG as fuel burns) you're right
on the 103" limit. Anyone/anything in the
rear seat, at 103", will NOT move the CG aft