Hi Josok
"It's the stall that i am interested in, and that has little to do with the
Angle
of Attack. But please correct me if this makes no sense!"
I am sure you understand the point it is that you are trying to make, but AOA
has
everything to do with the stall, so please elaborate as statement above makes
no sense to me.
I think perhaps point it is you are trying to make is Airspeed has little to do
with stall??
Dynon AOA will show you surplus of lift that is available before stall will
occur
at a given weight, and airspeed and angle of attack.
If all things are equal:
A low all up weight will be flying at less AOA than heavily loaded thus more
surplus
lift on lower weight
Holding altitude with steeper bank angle will rapidly eat into your excess lift
available
The greater the airspeed the more excess lift you will have available
In other words you can't use your airspeed to determine very easily when you
will
stall, AOA can easily tell you when you will stall.
I fly the same 48" flying wing model between all up weight of 8oz in pure glider
form, to a 3/4 horse power 100mph plus 80oz monster. It is the same wing and
the same airfoil. Guess what, they stall at the same AOA! True straight and
level
the 8 oz glider may stall at 4MPH, and the 80 oz monster in a 75 degree bank
angle holding altitude may stall at 50 mph, but it is the same angle of attack
that both will stall. Thus even if I had airspeed available, unless I did
complex calculations I would not know when stall would happen. All that said
if you fly plane with bottom of wing at less than about a 18 degree angle of
attack as compared to the horizon I will not stall.
Dynon AOA that is fully functional will tell you no matter what your airspeed
is,
what your all up weight is, what your bank angle is when you are getting close
to stalling. I know I can fly a plane without such information, butAOA can
be a useful tool.
Go ahead and overshoot base to final turn in a fully loaded Europa at a high
density
altitude with most aft allowable CG, and bank and crank low to the ground
with increasing tailwind the lower you go (bad since your ground speed will
be increasing and will increase your overshoot), get that plane to a 60 degree
bank, just keep plenty of surplus lift being shown on the AOA and you are good
to keep that wing flying. If you have plenty of surplus lift you could even
be flying sloppy and skidding and you will not snap upside down. That may mean
dropping the nose a lot lower than you are used to and having a much higher
groundspeed
than you are used to, but that's OK because you will not stall where
you don't have time to recover, just drop nose and add power and increase
groundspeed
till AOA is happy. If flying at a safe AOA will not work and allow a
landing just go around.
Lower powered jets some private owners fly use AOA extensively.
Ron Parigoris
Visit - www.EuropaOwners.org
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