Schweizer 1-35 and other flapped sailplanes

Maule Driver wrote:

But I've landed in extremely gusty/wind shear conditions on several
occassions. That is, with T-storms over or on the airport (stupid?
Yes.) Flying with spoilers and flaps saved the day. Upon reflection if
given a choice between the 2, it would have to be spoilers. In those
admittedly extreme conditions, airspeed excursions are not entirely in
one's control and spoilers-only are better than flaps-only no matter the
level of pilot proficiency.

A couple HP owners told me that spoilers are preferable to flaps when
flying fast under clouds with strong lift:

* if the lift suddenly increases and threatens to suck you into the
cloud, spoilers can be quickly deployed keep you below the cloud.

* flaps will first increase the lift as you begin to lower them, and
take you into the cloud. Increasing speed to stay out of the cloud may
put you over the speed limit for the flap setting you need avoid the cloud.

Have other HP owners encountered this situation, and how do they cope
with it?

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Eric Greenwell
Washington State
USA

I've never flown an HP. Getting sucked into a cloud seems to primarily
be a strong conditions (e.g. Western US) problem. Happened to me in an
LS6... have no idea what I'd do with a flaps-only ship except exceed
redline. Deploying the spoilers at close to redline scared the stuff
out of me as it was, but it worked.

Eric Greenwell wrote:

A couple HP owners told me that spoilers are preferable to flaps when
flying fast under clouds with strong lift:

* if the lift suddenly increases and threatens to suck you into the
cloud, spoilers can be quickly deployed keep you below the cloud.

* flaps will first increase the lift as you begin to lower them, and
take you into the cloud. Increasing speed to stay out of the cloud may
put you over the speed limit for the flap setting you need avoid the cloud.

Have other HP owners encountered this situation, and how do they cope
with it?

"Maule Driver" wrote ...
I've never flown an HP. Getting sucked into a cloud seems to primarily
be a strong conditions (e.g. Western US) problem. Happened to me in an
LS6... have no idea what I'd do with a flaps-only ship except exceed
redline. Deploying the spoilers at close to redline scared the stuff
out of me as it was, but it worked.

Eric Greenwell wrote:

A couple HP owners told me that spoilers are preferable to flaps when
flying fast under clouds with strong lift:

* if the lift suddenly increases and threatens to suck you into the
cloud, spoilers can be quickly deployed keep you below the cloud.

* flaps will first increase the lift as you begin to lower them, and
take you into the cloud. Increasing speed to stay out of the cloud may
put you over the speed limit for the flap setting you need avoid the
cloud.

Have other HP owners encountered this situation, and how do they cope
with it?

Having flown an HP-14 for 195 hours and a much-weenier-flapped Zuni for
several thousand, all of it out west, and having in both been concerned
about getting sucked into strong cloud streets, here's what I did:

1) immediately slowed down (to some speed below which full flaps could
easily/safely be put down);
2) put down full flaps;
3) changed course to the nearest cloud edge.
4) gave thanks I was flying a flapped ship!

Low stress, structurally safe. Even if one was so
foolish/bold/situationally-unaware as to go into the cloud immediately upon
the pull-up to slow down, who among us canNOT simply provide a stick input
until the stall, prior to losing control in the cloud? If a pilot can do
that, s/he can put down the flaps after the speed bleeds down. (Individual
mileage may vary. Not approved by the Insurance Institute of America or the
American Bar Association.)

Short of having the magic fairy wave a magic wand, I've a hard time
imagining anything simpler and safer in glider/cloud-avoidance terms. If -
for the sake of limiting this discussion - we ignore *how* one comes to be
in the situation of realizing cloud avoidance is (thought to be) a
necessity, and consider only the (forced) choices of either a) opening
spoilers at high speed for the first time beneath a cloud AND successfully
staying out of said cloud (e.g. Maule Driver!), or b) pulling on full flaps
at low speed AND unsuccessfully NOT staying out of said cloud (not me!), the
coward in me opts for "b)" in a heartbeat. Even with the Zuni's wimpy
large-deflection flaps, there is ZERO risk of exceeding maneuvering speed
and pulling the wings off in a spiral dive, because one must *hold* forward
stick w. full flaps to maintain flying speed.

And, yes, the above was tested and incorporated in a plan long before
needing it in both ships...

Regards,
Bob - gliders can never have too much disposable drag - W.

That seems like a workable plan and well thought out.

But, the 6 allowed spoiler deployment up to redline as I recall so
pulling the spoilers was a perfectly legit operation and resulted in
immediate slowing and increased descent rate. Having the spoilers
sucked out and whistling at close to redline did get my attention along
with the hail coming at me from below.

The best solution is 'terminal velocity' spoilers that once deployed,
prevent acceleration to redline. 1-34 had 'em I think. Nice but not
required.

Flaps are workable, spoilers still seem just a bit better to this pilot.

Bob Whelan wrote:
"Maule Driver" wrote ...

I've never flown an HP. Getting sucked into a cloud seems to primarily
be a strong conditions (e.g. Western US) problem. Happened to me in an
LS6... have no idea what I'd do with a flaps-only ship except exceed
redline. Deploying the spoilers at close to redline scared the stuff
out of me as it was, but it worked.


Short of having the magic fairy wave a magic wand, I've a hard time
imagining anything simpler and safer in glider/cloud-avoidance terms. If -
for the sake of limiting this discussion - we ignore *how* one comes to be
in the situation of realizing cloud avoidance is (thought to be) a
necessity, and consider only the (forced) choices of either a) opening
spoilers at high speed for the first time beneath a cloud AND successfully
staying out of said cloud (e.g. Maule Driver!), or b) pulling on full flaps
at low speed AND unsuccessfully NOT staying out of said cloud (not me!), the
coward in me opts for "b)" in a heartbeat. Even with the Zuni's wimpy
large-deflection flaps, there is ZERO risk of exceeding maneuvering speed
and pulling the wings off in a spiral dive, because one must *hold* forward
stick w. full flaps to maintain flying speed.

The Glasflugel Mosquito flap/spoiler combo is terminal speed limiting. I
believe that was a requirement until right around 1980?
I've fully deployed the flaps+spoiler on mine and pointed the nose something
near vertical and didn't exceed manuvering speed. The POH says they can be
fully & abruptly deployed at up to redline, but be ready for the 2G
deceleration shock.


"Maule Driver" wrote in message
om...

The best solution is 'terminal velocity' spoilers that once deployed,
prevent acceleration to redline. 1-34 had 'em I think. Nice but not
required.

For Example John Smith wrote:

The Glasflugel Mosquito flap/spoiler combo is terminal speed limiting. I
believe that was a requirement until right around 1980?

It disappeared in the mid or late 60's, which is why the Std Cirrus and
other late 60's - early 70's gliders had relatively weak spoilers.

My ka-6E had terminal speed limiting spoilers, and I enjoyed their
ability.

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Eric Greenwell
Washington State
USA