Schweizer 1-35 and other flapped sailplanes

I've seen several remarks lately in Soaring Magazine and on my home
club's internet forum about the characteristics of this particular
sailplane. Though not directly bashing this ship, comments made seem to
imply that it's a difficult or dangerous sailplane to fly. I think
that's wrong. Some of these comments imply that low-time pilots need to
shy away from this ship, and that takeoffs and landings are a problem.

I shouild tell you that 128 of my 220 hours in sailplanes are in a
1-35, with another 12 in my PIK-20B. It's as easy to fly as a 1-26, in
my opinion, and we regularly let solo students go in those. My first
flight in the 1-35 came when I had 27 total hours in my log book. I had
mentioned liking the looks of the ship and a desire to fly it. I had
also mentioned my fear of the ship, fostered by comments of some that
had flown it... and those FLAPS... egad!!! Those flaps!!!

Hearing my comments, a fellow TSAer and feminine ASW-20 pilot, told me
there was nothing to fear, that it was just another sailplane. She said
that it had some characteristics that were different from spoilered
ships that had to be respected, that's all. She did me such a great
favor with her comments.

I got an instructor that was familiar with that ship to check me out in
it. He had me memorize the speeds, familiarize myself with the
controls, etc... all pretty normal. Then they had me sit in the
sailplane and lifted the tail to show me the flight attitudes I would
encounter. For my first tow, he had me take off with full negative
flap, and wanted me to take it to thermal position when I had full
aileron control. The tow pilot was instructed not to daudle on initial
acceleration. When I pulled the flaps back to +8, she popped off the
ground and I had a better view of the tow plane than I had ever had
before. Per the instructor, I took a 4K' tow and made 3 mock patterns,
including full flap final approach, with the 4th one to be the first
real landing. I was initially uncomfortable with the nose-down
attitude, but after seeing that those flaps kept the airspeed down, it
became second nature pretty fast. I couldn't believe how well I could
see the airport on final. I was really pleased that by keeping the
airspeed at 60, I could let the flaps off and level the attitude and
clear obstacles... to the other end of the field if necessary.

My first landing in this ship hooked me. I flared by releasing some of
the forward pressure, and at full flap, the airspeed bled away so
quickly that I was amazed. When I heard the first grass touching the
ship I went to full negative flap and touched down on the main and tail
wheel at the same time, at about 35 mph. Where was my fear? Well, it
was where it should have been... gone.

I have heard others bash flapped ships for my whole soaring life. These
comments always seem to come from those that have very limited
experience in these ships, or had bad advise from those that checked
them out in these designs. I recently bought a PIK-20 and it's previous
owner told me a horror story about his first takeoff - with +45 degrees
flap cranked in on advise from an instructor. Was that the fault of the
flaps or the design? I can well imagine the resulting pitch up and
white-knuckled response.

So, my wish is... If you've had a bad experience in such a bird, that
you analyse this experience with someone that regularly flys one.
You'll probably find that you didn't get good instruction, or didn't
follow it. I'm living proof. If I can survive 140 hours in a flapped
ship and not just survive but love it... so can you. They're not
dangerous, just different. Not to be feared, but respected. Let's face
it, if you don't respect a 1-26, it'll kill you.

Stop kicking my old friends... the 1-35s.

Jack Womack

"Jack" wrote...

(selectively snipped
I've seen several remarks lately in Soaring Magazine and on my home
club's internet forum about the characteristics of [a 1-35]
sailplane. Though not directly bashing this ship, comments made seem to
imply that it's a difficult or dangerous sailplane to fly. I think
that's wrong.

"Roger that last sentence!"
- - - - - -

I have heard others bash flapped ships for my whole soaring life. These
comments always seem to come from those that have very limited
experience in these ships, or had bad advise from those that checked
them out in these designs.

Bingo!...
- - - - - -

I recently bought a PIK-20 and it's previous
owner told me a horror story about his first takeoff - with +45 degrees
flap cranked in on advise from an instructor. Was that the fault of the
flaps or the design?

Indeed...
- - - - - -

So, my wish is... If you've had a bad experience in such a bird, that
you analyse this experience with someone that regularly flys one.
You'll probably find that you didn't get good instruction, or didn't
follow it. I'm living proof. If I can survive 140 hours in a flapped
ship and not just survive but love it... so can you. They're not
dangerous, just different. Not to be feared, but respected. Let's face
it, if you don't respect a 1-26, it'll kill you.

Well said, spot on, and "Roger your wish and sentiments!"
- - - - - -

Stop kicking my old friends... the 1-35s.

IMHO inaccurate/misguided opinions seem to travel faster & wider than the
truth, but the good news is the truth seems to have more sticking power in
those determined to seek it out. Congratulations on being able to find &
apply it in this instance!

Regards,
Bob - no-sweat transition from 1-26 to large-deflection-flaps w. 125 hours -
W.

In article ,
"Bob Whelan" wrote:

"Jack" wrote...

(selectively snipped
I've seen several remarks lately in Soaring Magazine and on my home
club's internet forum about the characteristics of [a 1-35]
sailplane. Though not directly bashing this ship, comments made seem to
imply that it's a difficult or dangerous sailplane to fly.


Yep, the ol' "Flaps of Death" fallacy. Just imagine if the 1-35 were a
V-tail!

I have only flown one glider that uses flaps alone for glidepath
control: an HP-16 (Thanks again Dr. Jim). Clearly, I cheated death as
neither the flaps nor v-tail got me. Absolutely lovely ship and flies a
lot better than my 301 Libelle. Easy to pick a spot and land on it. I'd
be more at ease landing out in the HP-16 than my Libelle.

I think the key is to use enough flap. I've seen too many folks in the
1-35, PIK, or HP's timidly crank in only about half flap and then dive
at the runway. They end up too fast and do the funny looking glide down
the field with their tale way up in the air. Turn final high and crank
them flaps in at least 70 degrees and it's easy from there.

Actually, my favorite system is the trailing edge flap/divebrake combo
used on some of the Glasflugel and Schempp Hirth (and Caproni A-21 if I
rememember correctly). Best of both worlds, but difficult to seal up air
leaks. Not a concern on the older design ships they are found on, but
new ships have laminar flow so far back on the wing that sealing of the
flaps is critical.

I still don't really care for the 1-35 very much, but that is because
better gliders can be had for the same (or less) money.

--
Take out the airplane for reply

IMHO inaccurate/misguided opinions seem to travel faster
& wider than the
truth, but the good news is the truth seems to have
more sticking power in
those determined to seek it out. Congratulations on
being able to find &
apply it in this instance!

Regards,
Bob - no-sweat transition from 1-26 to large-deflection-flaps
w. 125 hours -
W.


On the other hand for us cheapskates...this keeps ships
such as the Ventus B affordable! R trailing edge devices
different? U bet. Should they reduce the value of
the ship? Personally I believe the opposite. Having
said that, the Ventus deserves it reputation for less
then sweet handling characteristics.

What sweet memories. As a low time glider pilot, my few flights in a a
1-35 hooked me on flaps. They are a bit different, not necessarily
better, but certainly not dangerous. And the 1-35 is a sweet example.

So my first owned sailplane was a PIK20b. Great ship too. Once one
learned to wind up the flaps while flaring, it could be landed on a
dime. But the path to learning that technique was paved with PIOs
(think rubbing you tummy while patting you head expressed in pitch).

Thanks for the memories...

Jack wrote:

I shouild tell you that 128 of my 220 hours in sailplanes are in a
1-35, with another 12 in my PIK-20B. It's as easy to fly as a 1-26, in
my opinion, and we regularly let solo students go in those. My first
flight in the 1-35 came when I had 27 total hours in my log book. I had
mentioned liking the looks of the ship and a desire to fly it. I had
also mentioned my fear of the ship, fostered by comments of some that
had flown it... and those FLAPS... egad!!! Those flaps!!!

Maule Driver wrote:
What sweet memories. As a low time glider pilot, my few flights in a a
1-35 hooked me on flaps. They are a bit different, not necessarily
better, but certainly not dangerous. And the 1-35 is a sweet example.

So my first owned sailplane was a PIK20b. Great ship too. Once one
learned to wind up the flaps while flaring, it could be landed on a
dime. But the path to learning that technique was paved with PIOs
(think rubbing you tummy while patting you head expressed in pitch).

Thanks for the memories...

You would raise that flaps in the flair? In my Ventus, and now the
Mosquito I fly, that would be really difficult, and the opposite of what
a lot of people do-extending more flap in the flair. I favor the set
'em and forget 'em on short final method. Granted, not quite the same
system.
Do Piks HPs and 1-35 flaps create too much drag to leave out in the flair?

Shawn

Our local DE had a 1-35 on the line, which he mentioned to me when I
mentioned my plans to buy an HP-11. He gave me some advice then, and
in retrospect it was very good advice.

First off, flaps for glideslope control are not an issue. Really no
big deal at all. Sure, a little different, but not difficult.

The issue with my HP-11, and the HP-18 my friend had, and the 1-35 the
local DE had, was weak aileron control on takeoff. On a wide grass
field with a powerful tow plane and all tows into the wind, it's not
much of an issue - you rudder it around until the ailerons come alive,
and then all is well. On a narrow paved runway, with lights on posts
giving the wingtips just a few feet of clearance, a weak tow plane, and
a habit of towing slightly downwind to avoid the inconvenience of
moving, it's a much bigger deal.

Michael

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

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

I owned an HP-11 for over a dozen year, and I own an HP-18 now. I love
large-span flaps for glidepath control, and I dearly wish I could
market sailplanes with them. Unfortunately, there are few 2-seaters to
train pilots on them with, and much in the way of rumor and
disinformation about them.

Feed-forward is the key to using large-span flaps for glidepath
control. As you crank in the flaps, you have to simultaneously apply
nose-down pitch. You can refine the pitch input as you go, but you have
to start both the flap and pitch inputs at the same time. If you try to
do it reactively, that is add some flaps and then adjust the pitch when
you detect the airspeed change, you quickly end up way behind the
curve.

In the HP-11, I would often crank on the last bit of flap in the flare
in order to achieve touchdown at the lowest possible energy level. It
takes practice, but once you develop the techniques it becomes easy.

Bob K.
http://www.hpaircraft.com

There are several articles relevant to the use of large span flaps on the
"Schreder Sailplane Designs" web site. (http://www.soaridaho.com/Schreder)

See:
http://www.soaridaho.com/Schreder/St..._HP_flight.htm
http://www.soaridaho.com/Schreder/Large-span_flaps.html
http://www.soaridaho.com/Schreder/St...r_on_Flaps.htm

You can get a lot of sailplane for the dollar if you purchase a use
HP/RHJ/RS sailplane.
http://www.soaridaho.com/Schreder/Tr...ding_Post.html

Wayne
HP-14 N990 "6F"
http://www.soaridaho.com/

"Bob Kuykendall" wrote in message
oups.com...

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

I owned an HP-11 for over a dozen year, and I own an HP-18 now. I love
large-span flaps for glidepath control, and I dearly wish I could
market sailplanes with them. Unfortunately, there are few 2-seaters to
train pilots on them with, and much in the way of rumor and
disinformation about them.

Feed-forward is the key to using large-span flaps for glidepath
control. As you crank in the flaps, you have to simultaneously apply
nose-down pitch. You can refine the pitch input as you go, but you have
to start both the flap and pitch inputs at the same time. If you try to
do it reactively, that is add some flaps and then adjust the pitch when
you detect the airspeed change, you quickly end up way behind the
curve.

In the HP-11, I would often crank on the last bit of flap in the flare
in order to achieve touchdown at the lowest possible energy level. It
takes practice, but once you develop the techniques it becomes easy.

Bob K.
http://www.hpaircraft.com