On 6/16/2017 5:55 PM, wrote:
I have a secret.

Well, like secrets in a Congressional Intelligence subcommittee, this one
is probably known by several hundred people. But I haven’t written about
it. Until now.
Lucid write-up of two wing-drop-included takeoff runs snipped

But I was humbled. How could I have messed up so badly? One respected
colleague offered that I had failed to have a contingency plan. But that’s
not true. I had a plan; I just ignored it.ng runner, as another ground
crew member did a few days later as we chatted on the line. His
inexperience almost certainly triggered the i



I could have blamed the tailwind and young wincident. But the fault for the
damage was all mine. I could have prevented it by pulling the release. Why
didn’t I?

I think it came down to ego. I remembered thinking I had made a mistake in
dropping the wing, a mistake I wanted to--and was convinced I
could--correct. And I was sure, until I landed that night and even for a
few hours afterward, that I had acted reasonably, that the landing light
hidden in the high grass was just one of those things that can’t be
controlled and that my decision to try to recover from a takeoff gone bad
was justifiable. After all, I would have gotten away with it except for the
light.

I was wrong. The correct decision was to pull the release immediately, the
way I had several times in earlier years and the way I did two days ago.
Some decisions are easy: we make them before we fly and all we have to do
is execute. Are there times when we should modify our contingency plans due
to circumstances? Sure, but we need a better reason than trying not to look
stupid or saving a few minutes on the launch grid.

Chip Bearden “JB”

Thanks for sharing your experience (and experiences), Chip. I completely agree.

Sharing and discussing these sorts of things is - IMHO - the *other*
fundamental raison d'etre of RAS...as methinks is well-demonstrated by Jordan
Pollock's question (i.e. "How does extended spoilers improve aileron
response?") elsewhere in the thread. It's a question I think I first
encountered in print several decades ago in "Soaring" magazine, and which I'll
toss out for discussion my 2-cent's-worth response. Undoubtedly others will
contribute/elaborate/disagree...all good stuff in principle.

The way I think about raised spoilers enhancing roll response during takeoff
is this: by reducing the amount of total lift the wing is producing, the
"aerodynamic roll stiffness" is reduced, hence any aileron input will have
less roll inertia to overcome. Viola! Improved roll response. (Imagine a wing
infinitely stiff-in-roll at all speeds - there'll be zero aileron effect.)
Others have (and likely will) posit at least one (other/secondary?) effect
related to the changed spanwise flow-field over the wing positively
assisting/improving the ailerons' flow fields (hence improving their actual
"power"). If this is so, I'd expect short-spanned gliders to (painting with a
broad brush, here) to be more likely to benefit from use of the open-spoiler
technique than long-winged birds, because of short-spanners' lower,
mass-related, roll inertia.

FWIW, the same thinking "works" for camber-changing-flap-equipped birds, and
at least for the one in which I have all of my experience, it can be shown to
"work" in reality, as well. Next time you're ground-bound on a day with a more
or less steady 10-15-knot breeze, face your ship into the wind, snag a
wing-tip buddy for a few minutes of experimentation and fun. Have your buddy
level the wing and let go on your command while you attempt to keep wings
level. Odds are you'll find it's easier to do so with
spoilers-open/flaps-negative than not.

Bob W.

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