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Old February 12th 15, 08:04 PM posted to rec.aviation.soaring
Jonathon May[_2_]
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Posts: 88
Default Overspeed Recovery question

At 16:12 12 February 2015, Michael Corcoran wrote:
At 15:10 11 February 2015, Dan Marotta wrote:
How can you "inadvertently fly into the yellow range and kiss the red
range"? Sleeping at the helm? You have to have quite a nose down
attitude to get near the red line and it doesn't sneak up on you. It's
very noisy and pitch sensitive.

Don's advice below is excellent.


On 2/11/2015 3:20 AM, Don Johnstone wrote:
At 02:58 11 February 2015, wrote:
If you inadvertently fly into the yellow range and kiss the red

range,
and

you get into the high speed vibration, what is the best way to slow
before

the wings depart the glider. My sense is to reach for the spoiler

and
slo
wly extend to slow. Any opinions on that matter?

A very experienced test pilot once told me, and several others, that

if
you
were faced with exceeding VNE you should pull as hard as you can,

even
if
it means exceeding max G load, to reduce speed as soon as you can to

below
VNE. Catastrophic structural failures due to excess G are very rare

unless
there are other factors, catastrophic failures due to flutter ar

almost


inevitable.
There is no right answer, just a less wrong one and I would stress

have
not had the opportunity to test this.
One of the requirements on a Grob 103 post major inspection test

flight
was
to operate the spoilers at 70kts, having done this many times I woul

not
recommend the spoilers option.


--
Dan Marotta


Once, while practicing aerobatics in my Pilatus B4, and entirely due to m

own clumsiness, I found myself in a 45 degree inverted dive and rapidly
approaching Vne. Fortunately, I did what I was trained to do, which was t

push hard until the nose was above the horizon, then roll out. It was all


captured on my cockpit mounted Go-Pro. This shows the momentary
hesitation while I overcame the instinct to pull. The ASI shows 130knots
(Vne) was just touched, and the accelerometer, after initially bein
obscured
by my left arm rising to be firmly held against the canopy, showed -4g.

Had I pulled through, I would probably have exceeded Vne by 30knots.

On landing, the aircraft was thoroughly checked, and found to have

suffere

no ill effects.

I am thankful for the thoroughness of my training, and for the robustnes
of
the B4



I'm Genuinely relieved that the original poster is not a trained glider
pilot,because most people once trained are so used to speed control the
situation does not occur.
Which is why we have been talking about loosing control in clouds or
failing
to allow for the reduced VNE at altitude.
Presumably if you fly high enough you can get to a coffin corner where the

stall speed is higher than the hight adjusted VNE but we should be so lucky

as to get there.
I was impressed with the pushing to recover from an inverted dive ,not
something to try without proper training.
Fun thread ,hope the snow melts soon.