On Aug 31, 9:44*pm, wrote:
On Friday, August 31, 2012 6:11:41 PM UTC-4, kirk.stant wrote:
There seems to be some confusion in this thread about spins. *A spin is a stable autorotation with the wings stalled and fairly constant airspeed. A departure is when the your glider starts to do something that you didn't tell it to do or want it to do, either because you got too slow and stalled it, or a gust upset it, whatever. *A spin entry, in a glider that will actually spin (not all will), is a controlled departure held long enough to stabilize into a spin.

But a departure doesn't have to result in a spin. *If corrective action is done promptly and correctly (almost always involving unloading the wing by reducing AOA), the glider will resume flying and will never get to the autorotation state. *Many (most?) glass ships, unless the CG is way aft or flaps are in landing configuration, are reluctant to spin, probably due to limited elevator authority. *They may depart, and if you sit there like a bump on a log and don't apply corrective action, may progress to a spin, or a spiral dive, or just recover on their own.

But if you experiment (at safe altitude) with the glider you fly, trying all it's configurations and finding out how it reacts to a departure, you will be prepared (like Bruno) to safely recover from a departure with minimum loss of altitude (or danger to your gaggle mates).

This is BASIC stuff, guys. *If I'm just telling all of you what you already know, I apologize. But if you really don't understand this (and some of the discussions on RAS about AOA makes me think many don't) then please get with an acro/spin instructor and brush up.

Cheers,

Kirk

66

Maybe its not so basic, but then what do I know. If both wings are stalled, then you just have a stall, the nose drops and recovery is easily accomplished. If you stall in turning flight or uncoordinated use of controls, then the slower wing will stall and an autorotation will commence. The outer wing is not stalled. Correct me if I'm wrong.

Tom- Hide quoted text -

- Show quoted text -http://www.youtube.com/watch?v=PpJA53LjarM

Yes and no. I was repeatedly taught the same spin theory (i.e., one
stalled; one not), but in a spin both wings are apparently stalled but
with one wing deeper than the other. During the incipient phase in a
controlled turn, I have read where both wings stall simulaneously,
while if uncoordinated the inboard wing stalls first before the
outboard. Back on topic, from what I read in the flaps-out landing
configuration the ASW-20's interconnecting flap/aileron system moves
the ailerons to -8deg, a design intended to reduce the chance of a tip-
stall at low altitude. Where I disagree with "66" in the ASW-20 video
is that the pilot applied the POH-recommended spin recovery at high
altitude (according to the pilot's own words). He's in a tight turn,
near or below the slowest part of the ASI white-arc range when he
encounters a gust (increasing AOA). As the incipient phase begins and
the wing drops hard, he first rapidly moves the stick further towards
the outboard wing (opposite aileron) with no opposite rudder input.
His reflexive move is to reduce flaps to full negative (per the POH)
while still holding opp aileron.. The resulting decrease in AOA is
what presumably unstalls the wings. I think this is right. When low,
the POH recommends not reduceing flaps, but rather to carry extra
speed. Good lesson.