Colyn,
You asked a legitimate question about “feel” at
weights above 3200 lbs. and haven’t had a direct answer. I think I
know why; it’s hard to answer. I’ve flown my 3200# IVP to
3300, 3400 and 3500 in controlled conditions, on purpose, so I would know my
airplane’s capabilities better, for the same reason I’ve practiced slow
flight in the burble and now know exactly when to unload to catch the snap roll
just as it starts (and yes, I’ve been late and had to recover from vertical,
and tried it again, and again. Now I believe.)
To me, it’s a progressive feeling of discomfort as I
exceed 3200#. My CG is always within limits, albeit moving aft as the
weight increases, but the airplane becomes progressively more “sensitive”
(unstable?) in pitch. It is mostly noticeable immediately after takeoff where
the pitch inputs needed become relatively exaggerated to correct a slight
tendency towards pitch porpoising. (I don’t have winglets and others may
have a different feel than mine.) Higher gross also (obviously) leads to
a longer T/O roll, slower acceleration to climb speed and a decreased climb
rate. The airplane can handle it, and has, but all the training and
experience that I have garnered in 50 years of challenging flying has sensitized
me to those first moments of flying after takeoff to initial climb speed with
the airplane cleaned up and able to maneuver to an off-airport parking place. Gross
weights that cut my margin make me squirm.
Let me help you rethink your needs. My aircraft has an
empty weight of 2235 lbs. Yours may be more or less. I have the
original 80 gallon fuel capacity and no winglets. Full fuel, two FAA occupants
and 100 lbs of baggage puts us at 3165 lbs. The airplane flies
great. It’s three easy legs to Santa Barbara
from eastern Ohio
and two legs back. Extended fuel became an option after I had closed my
wings and I would have added it but LOP operation, which I learned from George
B. in the Cayman Islands 5 or 6 years ago, made up for the gas that I now don’t
have to carry. My guess is that you will also become uncomfortable at the
higher gross weights or simply have no reason to operate there and, regardless
of what your DAR will “give” you, most of your flights will be like
mine.
Brent comes at this question from a hard-nosed engineering
perspective. Brent should be taken seriously, as should Charlie K.
I’m not an engineer, or a DAR, but I have had to fly
at the edge of the performance envelope, and test it, in the past. In
that context, I think that I would not have any fun flying the IVP at 3500 lbs
or above on a routine basis because it would make me squirm, adding stress
which reduces fun, etc.
Whatever weight you certify your plane for, Colyn, you have
now had serious input, as has Jeff L., the original questioner. Thanks
for asking; you are now less likely to affect our insurance rates.
Carl La Rue