Schweizer 1-35 and other flapped sailplanes

Do Piks HPs and 1-35 flaps create too much drag to leave out in the
flair?

Shawn

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~

As a PIK 20B driver:

It's not that they create too much drag, it's that it floats for quite a
long way even if your approach isn't fast, and in that float it is
_VERY_ pitch sensitive. The other problem is that once you are down on
the ground there is very little aeleron control and any brake will put
the aircraft on its nose, so it's much easier to complete the initial
part of the flare and then slowly wind in the flap so that the tail
comes down and it settles onto the ground, winding the flaps all the way
to negative allows use of the wheel brake and gives some aeleron
control.=20

Rgds,

Derrick Steed

Derrick Steed wrote:
Do Piks HPs and 1-35 flaps create too much drag to leave out in the
flair?
no
As a PIK 20B driver:
It's not that they create too much drag, it's that it floats for quite a
long way even if your approach isn't fast, and in that float it is
_VERY_ pitch sensitive. The other problem is that once you are down on
the ground there is very little aeleron control and any brake will put
the aircraft on its nose, so it's much easier to complete the initial
part of the flare and then slowly wind in the flap so that the tail
comes down and it settles onto the ground, winding the flaps all the way
to negative allows use of the wheel brake and gives some aeleron
control.=20

I'll second all of that on the PIK20b. First, I think the PIK, 1-35,
and the HP series are all different.

You will float too far in the PIKb using any reasonable speed over the
threshold. Since I learned CC soaring and outlandings in this ship,
precise touchdowns were required. The previous owner, an experienced
racing pilot, taught me the the "wind up the flaps as you flare"
technique after I had 'mastered the float'. I would almost always use
the full 90 deg position on final and wind it to neg 6 deg in the flare
- about 2.5 cranks as I recall. As you cranked, you pulled back and
landed 2 point. Very easy to hit any spot and very easy to do the flare
once you learned to coordinate cranking with one hand while pulling on
the other. You ended up being the afternoon's entertainment in the
meantime. That cranking motion invariably found it's way into your
right hand resulting in pitch PIOs.

If you don't touch the flaps, you would simply sit in ground effect and
wait for the energy to bleed off. Every gust or nudge of the stick
would cause excursions until the wait was over. Coming in on final with
minimum energy was unsafe. A unforseen drop in wind would leave you
without options....

....and that is the main problem with flaps. Once you have them out and
your energy is down, there's little recourse. With spoilers, you can
always slap them closed and return to high performance configuration.

Flaps are great but spoilers are better. Both is best.

Maule Driver wrote:

Flaps are great but spoilers are better. Both is best.

That's one of the reasons I prefer Schleicher gliders like the ASW 20,
and now a ASH 26 E.
--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA