DG Differences...
Just to assuage everyone's concerns: I am very familiar with the
importance of a trailer and good rigging. This is why I'm especially
keen on automatic hookups and something like a Cobra trailer. I've
SEEN the difference a trailer makes when I help certain people at my
field rig (even just in the difference between bracing / tie-down
methods in similar trailers can have a big impact), and understand
this point very well.
As for flapped performance: The reason I talk about speed is because
if you look at things like Idaflieg test data, the polar of say a
DG-300 and an ASW-20 are nearly identical at similar wing-loadings, at
about 55 knots and below. Above that the ASW-20 starts winning out by
a small margin to around 75 knots, and then above that the negative
flap settings seem to make a pretty noticeable difference in the polar
and the ASW-20 is the clear winner.
As another example: Look at the Johnson review of the ASW-20. Check
out the composite polar diagrams. Looks like you have to get up over
75 knots before the negative flaps really start becoming superior to
the 0-degree flap position.
This is why I'm phrasing things in terms of speed or XC distance/
aggressiveness. The "climb" flaps of the ASW-20 are certainly
superior (in small but noticeable ways) to the standard-class ships of
the late-70's. But the 80's standard-class ships seem to be equal to
the ASW-20 in terms of minimum sink and low-speed polar curves. Newer
airfoils seem to have a smaller "knee" in the polar curve at middling
speeds, but its still there for any standard-class ship. However its
the upper end of the polar that really seems to be the difference
(ignoring the landing-flaps deal). Am I off-base here?
*shrug* My longest XC flight so far is ~130 miles total distance-over-
ground on a 4 hour flight that didn't actually get too far from home-
base (low clouds in the mountains kept me from going where I wanted).
I'd like to be able to push a little harder to get from cloud to cloud
and cover more ground - but I'm not eager to risk landouts like one or
two "aggressive" pilots in my club who get low a lot, and land out a
good 3 - 4 times every year.
My XC experience to date is in a Russia AC-4 so I'm not sure how huge
of a jump its going to be when I move up to a 40:1 ship; maybe that
increase in performance alone will be enough to make me feel better
about cloud-hopping at slightly higher than best-L/D speed, or
stretching out a bit further to find lift.
I just don't have the experience to know if I'm really going to be
jonesing for that flap handle after I fly a standard-class ship for a
year... I thrive on challenges and new experiences - being bored with
my ship would be a nightmare!
Take care,
--Noel
P.S. Brad - I already looked at an Apis kit. Price of the Euro has
killed that for me! :-P
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