Aldo Cernezzi wrote:
any excess in speed
will be transfered to the water instantly: a big energy loss!
(a student has calculated the amount of energy needed to accelerate
100 grams of water from 0 to 60kts in a few seconds: it's about 3
times as much as the energy that would keep you flying level at the
same speed).


I'm puzzled by the apparent assumptions here,

Dear Derrick,
clearly there are assumptions. But I have deliberately flown my 400
into rain, and kept watching the canopy and the wings, trying to
investigate the behaviour of water droplets.
A wing can get very little or a lot of water per time unit, depending
on many variables. Anyway, 100grams of water (= 0,1 liters) is just
half a drinking glass. Not that much, over 10,xx m2 of wing surface,
plus fuselage and tail. It definitely looked possible, from my
perspective in the cockpit, in anything more than light drizzle.

I have then tried to use my method (extremely slow flying, and parking
in dry, zero lift, before leaving for a glide) in competitions, and
could notice a very big advantage against those who raced to escape
from the rain. No matter if they were flying an 800!

all the above, is IMVHO.

Aldo Cernezzi
now dg600 flyier

I can assure you that although it maybe doesn't come across that way the are
lots of "V"'s in my "IMHO". I'm just curious about other the experience
other people have, to get the full story it's sometimes necessary to
challenge assumptions.

My reasoning was based on one not being able to "parking in the dry", but
instead having to get out of the wet, it's not clear what is the best option
for this. I am only too well aware of the bad effect the rain has, and I
have tried the wing both polished and unpolished (interestingly, the form of
the water droplets was different in the two instances - unpolished, they
stood like little spikes). The real worry I would have is taking off or
landing with the wings very wet - once when visiting a hill site I called
off the launch on a winch three times before giving up and calling it a day
because of passing rain shower wetting the wings (another pilot stole the
only dry launch possibility I had that day - I'll never forgive him for
that).
I hope to hear more experiences, it all goes into the melting pot.

Rgds,
Derrick.