How Low to Spin??

Thanks Steve, good feedback and I like the process evaluation you describe.
Tools like SeeYou are terrific for that.

For the record, 300 feet is way too low for me too!

-ted

"Steve Hill" wrote in message
...
Ted,
in my humble opinion you are doing one of the healthiest things you
can
do for yourself for your long term survival as a sailplane pilot. Expose
your mistakes and share them. As a cross over hang glider pilot, I have
made
all sorts of small mistakes, I like to think I learned from most of them.
What I am completely convinced of is the need to not evaluate your
successes
or failures at this early point in your soaring by the "how high, how far,
how fast" methodology, but instead, to evaluate your process...download
your
flights and determine how many of your decisions were ones that could have
had bad conclusions, and then use those as a means to improve your
decision
making with each subsequent flight...I generally don't say much here, it's
more fun to simply watch the banter, but on this front I do feel compelled
to suggest that ALL cross country soaring pilots should be trying to share
more of the information we use in our own process. To me, 300 feet is WAY
too low to be trying to climb back up...once in awhile you'll get away
with
it...but not every time. And the one time it kills you, the pundits here
will have more fodder for the tireless " Well anyone could see it was
gonna
happen sooner or later"'s...My two cents worth ain't worth what it used to
be, but keep sharing those flights...if you aren't sure if it was
dumb...ask
somebody.."Hey would YOU have done this..?" and then be prepared for the
outcome.

In this case you got away with something. We've probably ALL gotten away
with something ourselves...but if we share a bit more of what was going
through our head, we can hopefully relegate some of the future visits to
funerals...


Steve
DG-400
4-93

In the late '70s, Airlines began to examine why certain accidents occurred.
They came to the conclusion that Cockpit culture needed to change.
Thus were born courses like "Cockpit Leadership and Resource Management"
Or CLR. It is now often called CRM for "Cockpit Resource Management"

It changed the premise of Airline Cockpit management from "The Captain is
always
right" to " The Captain is responsible for the final decision but will
gratefully accept
any and all input from any source to help him/her arrive at the safest
decision".

It was a remarkable event and, in my view, is responsible for the avoidance
of many accidents.

To do this Airline Pilots had to learn and embrace the difference between
critique
and criticism. Criticism is personality based and can be perceived as a
personal
attack on an individual. Critique, on the other hand, is situation based
and can and
should be based on events as they happened and how to learn from them.

As Steve suggests, it is better to critique than to criticize.

In the instant case, the question is, could Ted have landed at his intended
Airport
on his intended runway without thermal intervention? If the answer is yes,
then
ergo, he was not too low. If the answer is no, then ergo, he should
reevaluate
his decision making process. In any case, sharing the event with us
benefits all
and no one here should forget the difference between critique and criticism.

It has been my experience here that most do know the difference and I, for
one,
am thankful for that.

Allan


"Steve Hill" wrote in message
...
Ted,
in my humble opinion you are doing one of the healthiest things you can
do for yourself for your long term survival as a sailplane pilot. Expose
your mistakes and share them. As a cross over hang glider pilot, I have
made
all sorts of small mistakes, I like to think I learned from most of them.
...Snip...

want to hear about the very experienced pilot.. who in his first season with
his NEW ASW27B, found a thermal on downwind, thought he had it hooked.. only
to get left low and dry and forced into a downwind landing.. and totaled it
when it ground looped..

that extra tow back to that "found thermal" is cheap insurance

Anyone found "thremaling out" from 300ft in the traffic pattern would not be
asked to return. How many pilots did he block in the pattern while he
climbed above pattern altitude.

BT

"Paul M. Cordell" wrote in message
...
How Low to Spin??

I was proudly shown a IGC file this weekend. This file show the aero tow
thru a thermal and a release into sink. Our proud pilot was unable to
find the thermal and started a downwind leg for a landing. As he turned
base leg, he flew into a 2-5 kt thermal. Instead of completing the
pattern and landing, he turned and climbed in this thermal. The IGC file
showed that his altitude at the time of encountering lift was 300 ft. I
asked him 1 question as he displayed this flight on See You. How Low do
you want to spin?

His response scared me silly&&..My glider does not spin and there was no
wind.

He then continued to display the same flight where he bragged of
spending a considerable amount of time in the mountains within 500 feet
of the terrain. I am doubtful as to his ability to reach a landable area
during this portion of the flight.

This pilot is in his first year of private ownership, cross county
soaring and may have almost 200 hours of total time. He has embraced
soaring completely. I left the gliderport feeling that my suggestions as
to his safety practices were just hollow words. I know that he reads RAS
and would hope that the response to this post may give him some food for
thought.

that extra tow back to that "found thermal" is cheap insurance

A good point, and not forgotten at the time. I haven't shied away from
relights in the past, but I wasn't out to volunteer for one either.

How many pilots did he block in the pattern while he
climbed above pattern altitude.

None. As I told GY and Paul (before his post), I was careful to note as I
entered the pattern that I was the only one near it.

I'd noted when I launched that the entire commercial fleet was on the
ground. In the air (when I entered the pattern) were one tow plane with
which I had visual and radio contact, a motorglider several thousand feet
higher, and another glider just off tow two miles to the west.

Also, I didn't thermal at 300 feet -- that was the low point of the
downwind leg (it was actually a little more than 300', but why split hairs).
I was more than 100 feet higher when I started my first turn, to base. When
the lift continued, I simply decided to continue the turn (over 400 feet
now), plenty of altitude, airspeed and yaw string straight. At no point was
it any more dangerous than a normal landing pattern, and if I'm wrong on
that evaluation, I'm the first person who wants to know where why and how,
because if it was a mistake for those particular circumstances, I care not
to repeat it.

I was far more scared when my CFIG pulled the tow release at 200' without
warning in a heavily loaded trainer and I had to turn, line up on the same
runway we launched from, all while managing the airspeed, and land downwind.
(That's more than 180 degrees of turning, those of you who haven't enjoyed
this exercise before.) I had to perform that maneuver twice, once before 1st
solo and again just before my license exams. Was it safe? If so, then how is
what I did less safe, with twice the altitude and no surprises? I'm not
trying to be argumentive here -- I'm trying to understand what I should
consider next time that I did not consider this time, if there is anything.

Still I can't imagine "thermaling" at 300 feet unless there was terrain
underneath me I could imagine landing on even less. I hope that goes without
saying!

-ted

In article ,
Stewart Kissel wrote:
Part 2 of response-

Pushing limits safely is one of the appealing aspects
of our sport...once one can actually stay up, this
progression seems to be...

1.) How long(duration)
2.) How high
3.) How far
4.) How fast

An excellent list...how true...


(How low) seems to fit in there somewhere...but it
can bite harder then the others.

I saw an accident report that noted the cause:
"Pilot's inability to maintain terrain clearance."
Boy, that is SOME lazy investigator...I laughed a tiny bit,
and then was embarrassed at myself because it was a fatality...

I read a lot of reports about accidents caused not by
lack of lift, but presence of sink. In my close calls,
I was always glide ratio or better to an airport, but this
meant absolutely nothing. Sink is the killer.
--

------------+
Mark Boyd
Avenal, California, USA

In article ,
scurry wrote:
Paul M. Cordell wrote:

How Low to Spin??

When I flew my minature CA state record, at one point I had
picked a field and was on downwind for landing. The
stupid road on the field was 2000 ft long, but there
were trees 50-100ft+ on both ends, and a tree right in the
middle of the packed dirt road. I remember grumbling
to myself that this could very possibly suck.

I caught some lift on the downwind at about 500 ft AGL,
right over the field. I circled fast and with shallow bank
right over the field, in a wide arc. At every moment, I said
I wouldn't get slow and tight close to the ground, and if
I wasn't going up, I would go back to the downwind.

1 knot became 2, and soon I was at 1500AGL. I looked around a bit
more, and found that I had set up for a tailwind landing (about
5 knots). I hadn't seen any flags or such on the way in, and
the wind was 120 deg from what I expected.

I tightened up and took a breath, and eventually held the same thermal
up 10,000 ft, 4-6 knots.

So mediocre landing field vs. 500ft shallow circle at
higher speed? I'm gonna say that if I'm always in a position to make
a safe landing, I'm ok. The real question is if someone
flys slow and steep close to the ground. I do it high all the
time, but never below 1000 feet AGL...
--

------------+
Mark Boyd
Avenal, California, USA

Ted Wagner wrote:
yaw string straight.

We've had this discussion on RAS before. I'm still
gonna say that yaw string straight doesn't prevent a spin
entry. Spins are when you're stalled and one wing is more
stalled than the other.

One wing is more stalled than the other if one wing
has less AOA/more airspeed than the other. With the yawstring
straight, this is still true in a steep bank, especially
with long wings. It's also true if you're in a slip and
then with a punchy foot coarsely correct it to
center.

The steeper the bank, the higher the stall speed AND
the greater the difference in wing speeds, even with a straight
yaw string.

When I teach rope breaks, I do them at 300 ft and 30-45
degrees of bank, and best L/D for that bank angle.
http://www.stolaf.edu/people/hansonr/soaring/spd2fly/
is a start. I also caution against super rapid roll rates
and coarse use of rudder.

I'm open to thoughts on this. I didn't do the math to
see how MUCH the factor affects spins (somebody else did and
came up with 3 degrees diff or so for 50 deg and 18m wings),
but it sure surprised me.

Now when I do spins in the L-13, I do them from string centered
flight, and sure enough it always spins in the direction of the
steep bank, and in a hurry too...

P.S. Of course this assumes the rigging is right. If
flaps are lower on one side than the other, hey man, there's
yet another factor...
--

------------+
Mark Boyd
Avenal, California, USA

Ted,
I am pleased with the discussion that has occurred today.. As you
suggest, we must have experienced a failure to communicate. It
certainly is my intention to help you become a safer and better glider
pilot. As a side note, it has been a great pleasure to watch you
completely embrace this sport. I can only hope that we collectively
as a group will attract more people of your caliber. See ya @ the
gliderport!

Paul

scurry wrote:
Interesting thing about the flight; By following the ridge lines
keeping wind and sun in mind, I was able to run out of the hills at
300-400 feet over the ridges, maintaining my altitude until I had enough
altitude to circle comfortably (which, remember includes the thermals
spreading out enough to be useful).


Ridge flying is practised currently *much* closer to the ridge than that, in
fact so close than not touching some tree is the real problem.

--
Michel Talon

In article OrwWc.1538$4o.536@fed1read01,
"Ted Wagner" wrote:

Still I can't imagine "thermaling" at 300 feet unless there was terrain
underneath me I could imagine landing on even less. I hope that goes without
saying!

How about the opposite? I can't see much wrong with thermalling at 300
ft or lower if the ground underneath you is landable and unobstructed
such that you can roll level and land in any direction. Or on one of
those occasions where there is almost no lift about but no strong sink
either.

If conditions were at all boisterous then I wouldn't even consider it --
both because of the risk of a pin upset, and because of the risk of
hitting horrid 500+ fpm sink just as you're facing away from the field
-- but in the late evening when it's calm? Why not?

--
Bruce | 41.1670S | \ spoken | -+-
Hoult | 174.8263E | /\ here. | ----------O----------