In wave, in blue hole at cloud level, hole closes, in IMC, then what?

So I'm flying in a blue hole in wave lift of 5 m/s, trimmed to 50 knots, in clear air with a cloud layer upwind and downwind, cloud top above and cloud base below. Suddenly I find myself in IMC. What are my options?

My glider is capable of benign spiral. I open the spoilers, (already trimmed to 50 knots) and let go of stick and rudder. Then I mentally rehearse my bail out procedure and expect to come out below the cloud (or possibly above). It seems like I should decisively and without hesitation initiate the spiral ASAP, while the glider is still relatively level and at cruising airspeed.

Suggestions?

On Wednesday, April 8, 2015 at 7:08:36 AM UTC-7, son_of_flubber wrote:

Suggestions?

Flaps 90, and grind out of the bottom of the cloud at 50 kts.

Hmmmmmm, The spiral dive is exactly what you don't want! Think about it, your in the soup, cranked over holding your spiral and the airspeed keeps building. What do you do? Pull back to slow it down, right? There is a name for that situation, its called a dead-man-spiral.
I'm for pulling the spoilers, trim for 65 and turn loose. Try it next time you have extra altitude. I once logged something like 30 minutes in my H-301 Libelle (spoilers closed), she never went over 45 degrees and I hadn't touched anything for 30 minutes.
JJ

No problem in my 2-32, with dive brakes that won't let me go over VNE, but it didn't work at all in my Jantar 2A.

Boggs

On Wednesday, April 8, 2015 at 9:55:15 AM UTC-5, Bob Kuykendall wrote:


Flaps 90, and grind out of the bottom of the cloud at 50 kts.

Love my 90 degree flaps! You have to push to keep it up at 50 knots!

In his original post he said "benign spiral"...

My Mosquito had terminal velocity limiting trailing edge brakes.
My ASW-19 did a lovely benign spiral.
My LS-6a was divergent in pitch and would quickly go out of control
without positive inputs.

Haven't tried it in my LAK-17a... Must remember to give it a try at the
end of my next flight!

On 4/8/2015 9:04 AM, JJ Sinclair wrote:
Hmmmmmm, The spiral dive is exactly what you don't want! Think about it, your in the soup, cranked over holding your spiral and the airspeed keeps building. What do you do? Pull back to slow it down, right? There is a name for that situation, its called a dead-man-spiral.
I'm for pulling the spoilers, trim for 65 and turn loose. Try it next time you have extra altitude. I once logged something like 30 minutes in my H-301 Libelle (spoilers closed), she never went over 45 degrees and I hadn't touched anything for 30 minutes.
JJ

--
Dan Marotta

On Wednesday, April 8, 2015 at 11:04:10 AM UTC-4, JJ Sinclair wrote:
Hmmmmmm, The spiral dive is exactly what you don't want! Think about it, your in the soup, cranked over holding your spiral and the airspeed keeps building. What do you do? Pull back to slow it down, right? There is a name for that situation, its called a dead-man-spiral.
I'm for pulling the spoilers, trim for 65 and turn loose. Try it next time you have extra altitude. I once logged something like 30 minutes in my H-301 Libelle (spoilers closed), she never went over 45 degrees and I hadn't touched anything for 30 minutes.
JJ

HOLY CRAP!

On Wed, 08 Apr 2015 07:08:34 -0700, son_of_flubber wrote:

My glider is capable of benign spiral. I open the spoilers, (already
trimmed to 50 knots) and let go of stick and rudder.

I started a cloud-flying course last year and one of the first things we
were told was that, if you loose it in cloud, leave the trim where it
was, fully open the brakes and use feet and hand(s) to keep all controls
central, i.e. DON'T let go of the stick or take your feed off the pedals.

This takes advantage of the fact that most gliders are stable with brakes
open and controls centralised and not flapping about. Don't forget that
if the glider is pulling any G the stick can flop over and move elevator
and/or ailerons away from neutral if you're not holding it central.

Something similar might also occur in strong turbulence. If the stick is
raked or Z-shaped like a Libelle's, then its CG is behind the pivot, so
if you're pulling either positive or negative G than the offset stick
weight will tend to increase that if you're not holding the stick to stop
that happening.

A bit later in the season I did indeed loose it when LK8000 sounded an
airspace warning during a cloud climb and I manoeuvred too fast when
trying to avoid breaking into the bottom of the airspace. So, I did as
I'd been told and opened the brakes and then held the stick central and
the rudder straight. The glider, my Standard Libelle so fitted with weak
brakes, zoomed around a bit but didn't pull noticeable G or exceed Vne.
In fact I didn't notice it even exceeding Va. It came out the bottom of
the cloud more or less upright, so returning to straight and level was
perfectly straight-forward and didn't cost me more than 100 feet of
height.

Suggestions?

Do as I did if you don't pop out of the cloud fairly soon: this assumes
you were cruising in a straight line when the cloud got you and trimmed
more or less at Vbestglide. Open the brakes and centralise controls
immediately if you see the airspeed changing because that means you've
been upset by turbulence.

You'll have time to think about bail-out procedures later when you're
sitting, holding the controls centralised and waiting to exit the cloud.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Wednesday, April 8, 2015 at 11:22:24 AM UTC-4, Dan Marotta wrote:
In his original post he said "benign spiral"...

Right. Benign. The thing that is somewhat new to me is the possible desirability of initiating the benign spiral promptly, before the glider departs from a normal attitude.

My old Grob Speed Astir II (G104) had a benign spiral mode that was actually outlined in the flight manual. It worked.

My LS-8 will not hold a benign spiral. It begins a series of pitch downs and pitch ups that just keep gaining in amplitude and airspeed. I have not tried holding centralized controls but I can easily see where the plane would start banking due to turbulance and then you enter the death spiral.

Because of this, my new instruments have an artificial horizon (S80).