Yaw String in a Spin

In another thread Ian Strachan wrote:

'The standard recovery procedure once a full spin has
developed that
works for most aircraft is,

1. Full rudder opposite to the spin direction (make
sure it really is
opposite to the rotation, I for one have applied the
wrong rudder in a
spinning jet when I was caught by a surprise departure).'
=======================================

I have long surmised that application of the wrong
rudder in a panic situation might be a cause of failure
to recover from a spin. If it can happen to a military
test pilot of Ian's calibre then it can certainly happen
to me.

The yaw string *always* points to the inside of a spin
(according the Reichmann and others) and modifying
the teaching to 'apply full rudder opposite to the
direction of the yaw string' would be a more certain
way of choosing the life rudder pedal rather than the
death one at low altitude

Slip balls do not, apparently, invariably point to
the outside of spins so they are not as certain a guide.

'Every saiplane should have a yaw string' - said Helmut
Reichmann for this reason.

John Galloway

John,

interesting thoughts. Even with strong visual cues, the more nose down
a spin, the more difficult it might be to surmise its direction. Thus,
a quick reference to the yaw string is in order. Isn't the Pooch known
for its nose down attitude while spinning?

Yet another reason to put the emphasis on stall avoidance and prompt
recovery from prestall conditions. A suprise stall and autorotation at
low altitude presents a great a risk, even for well trained, heads-up
pilots.

I agree that this is an interesting point. Even experienced, current pilots
can be caught off guard, and perhaps a better training/recognition method
might be in order. Maybe the yaw string can/should be a more integral
part of the program in terms of spin recovery training?

For what it's worth, I have had a couple of unintentional spin entries over
the last 20 years. One in particular sticks in my mind. A guy at the
local gliderport is an experienced aerobatics competitor; he owns a two
place Fox aerobatic glider. He asked me to go up with him one day, since
he was having some trouble getting the Fox to climb. He figured thermals
were a lot cheaper than 5,000 foot aerotows.

We got into a moderate thermal, and I took the controls to show him how we
"real" soaring pilots thermal. I cranked us over to 40 degrees of bank to
core the thermal. "Now, watch how I slow us up to really tighten the
circle..." I said. The owner mentioned that I ought to "be a little
careful [since] stall speed at this..." He never finished the sentence.

Departure was instantaneous. Rotation was spectacular. I recall at first
doing everything wrong. It took me at least one full revolution to realise
that the glider was spinning, and I think it was a couple of seconds more
before I figured out the direction. Fortunately, we were at least 4,000
AGL at the time, and the owner just sat back and let me figure things out.

This flight came on a day when I had been the duty instructor in the club.
I had probably done 4 or 5 incipient spin lessons earlier in the day, and I
probably had 40 hours flying in the preceeding 90 days. So, I was current
and reasonably on top of my game.

This experience just reinforced the fact that the ability to recognize a
spin, especially an unplanned one, is probably not an easy thing to teach.
The normal training mode is thoroughly unnatural, as the student is primed
and ready. The reality is a lot different, and I'm wondering if any of us
emphasize the recognition aspects of the immediate post-departure moments
enough?

Erik Mann (P3)

wrote in message
oups.com...
John,

interesting thoughts. Even with strong visual cues, the more nose down
a spin, the more difficult it might be to surmise its direction. Thus,
a quick reference to the yaw string is in order. Isn't the Pooch known
for its nose down attitude while spinning?

Yet another reason to put the emphasis on stall avoidance and prompt
recovery from prestall conditions. A suprise stall and autorotation at
low altitude presents a great a risk, even for well trained, heads-up
pilots.

Since my original post today I mentioned the subject
to 2 instructors round the table at our club. One
had himself applied the wrong rudder in a spin and
he had also experienced a pupil doing the same.

When I was first taught spinning (aged 17 in 1969)
it was not immediately intuitively obvious to me which
way I was rotating without thinking back to what direction
the glider had been circling before departure - or
which wing had dropped if the instructor had started
the spin from a level stall. I confess that during
spin training, as the instructor started the spin
entry procedure, I made sure that I mentally rehearsed
in advance which rudder to apply - which rather defeated
the point I guess.

John Galloway


At 16:30 16 January 2005, Papa3 wrote:
I agree that this is an interesting point. Even experienced,
current pilots
can be caught off guard, and perhaps a better training/recognition
method
might be in order. Maybe the yaw string can/should
be a more integral
part of the program in terms of spin recovery training?

For what it's worth, I have had a couple of unintentional
spin entries over
the last 20 years. One in particular sticks in my
mind. A guy at the
local gliderport is an experienced aerobatics competitor;
he owns a two
place Fox aerobatic glider. He asked me to go up
with him one day, since
he was having some trouble getting the Fox to climb.
He figured thermals
were a lot cheaper than 5,000 foot aerotows.

We got into a moderate thermal, and I took the controls
to show him how we
'real' soaring pilots thermal. I cranked us over
to 40 degrees of bank to
core the thermal. 'Now, watch how I slow us up to
really tighten the
circle...' I said. The owner mentioned that I ought
to 'be a little
careful [since] stall speed at this...' He never finished
the sentence.

Departure was instantaneous. Rotation was spectacular.
I recall at first
doing everything wrong. It took me at least one full
revolution to realise
that the glider was spinning, and I think it was a
couple of seconds more
before I figured out the direction. Fortunately,
we were at least 4,000
AGL at the time, and the owner just sat back and let
me figure things out.

This flight came on a day when I had been the duty
instructor in the club.
I had probably done 4 or 5 incipient spin lessons earlier
in the day, and I
probably had 40 hours flying in the preceeding 90 days.
So, I was current
and reasonably on top of my game.

This experience just reinforced the fact that the ability
to recognize a
spin, especially an unplanned one, is probably not
an easy thing to teach.
The normal training mode is thoroughly unnatural, as
the student is primed
and ready. The reality is a lot different, and I'm
wondering if any of us
emphasize the recognition aspects of the immediate
post-departure moments
enough?

Erik Mann (P3)

wrote in message
roups.com...
John,

interesting thoughts. Even with strong visual cues,
the more nose down
a spin, the more difficult it might be to surmise
its direction. Thus,
a quick reference to the yaw string is in order. Isn't
the Pooch known
for its nose down attitude while spinning?

Yet another reason to put the emphasis on stall avoidance
and prompt
recovery from prestall conditions. A suprise stall
and autorotation at
low altitude presents a great a risk, even for well
trained, heads-up
pilots.

Since several experienced pilots have said that they have had trouble
determining the direction of the spin, I accept that it happens - and
that it can happen to me. I do not understand why. Most glider spins
happen when turning and, in the hunderds of intentional spins that I've
done (I have only one unintentional spin), the glider spins in the
direction of the turn. What am I missing? I do like the yaw string idea.

Tony V.

The first time I went over-the-top into a spin...it
definitely took a minute to figure out the rotation...others
experience may vary.


I was thinking about this topic and came up with this
observation....

1.) Training spin fatalities seem to happen from a
distance above earth that involves several rotations
before impact...for whatever reason, the spin developed
and could not be stopped.

2.) Inadvertant spin fatalities seem to almost always
occur so low (base to final)...that once the spin has
started, proper recovery probably would not save the
pilot.

So IMHO...are we really training for what is occuring?



At 18:00 16 January 2005, Tony Verhulst wrote:

Since several experienced pilots have said that they
have had trouble
determining the direction of the spin, I accept that
it happens - and
that it can happen to me. I do not understand why.
Most glider spins
happen when turning and, in the hunderds of intentional
spins that I've
done (I have only one unintentional spin), the glider
spins in the
direction of the turn. What am I missing? I do like
the yaw string idea.

Tony V.

At 12:00 16 January 2005, John Galloway wrote:
In another thread Ian Strachan wrote:

'The standard recovery procedure once a full spin has
developed that
works for most aircraft is,

1. Full rudder opposite to the spin direction (make
sure it really is
opposite to the rotation, I for one have applied the
wrong rudder in a
spinning jet when I was caught by a surprise departure).'
=======================================

I have long surmised that application of the wrong
rudder in a panic situation might be a cause of failure
to recover from a spin. If it can happen to a military
test pilot of Ian's calibre then it can certainly happen
to me.

The yaw string *always* points to the inside of a spin
(according the Reichmann and others) and modifying
the teaching to 'apply full rudder opposite to the
direction of the yaw string' would be a more certain
way of choosing the life rudder pedal rather than the
death one at low altitude

Slip balls do not, apparently, invariably point to
the outside of spins so they are not as certain a guide.

'Every saiplane should have a yaw string' - said Helmut
Reichmann for this reason.

John Galloway



Good post, but I must point out a trap. I learned
from a student that it is easy to misunderstand which
end of the string is doing the pointing.

I always taught students to 'step on the head of the
snake.' One student could never get it right (never
been around snakes) and he was stepping on the tail
-- the aft, unattached end. I found that other students
had figured out their own way of bringing the string
into line and just ignored my comments.

We should have a conversation with students specifically
about which end of the yaw string is the pointer/tail/indicator,
etc. and which foot does what to that end of the string
under discussion.

On the other hand, perhaps my analogies are just weird.

I had a two turn spin in my 20 a couple of years ago at a Mifflin
contest. The ship was in a coordinated right 45 degree bank, nose on
the horizon, and I was making my third searching circle attempting to
center the strong core of a good thermal. I was stable and coordinated
in the turn when the tail pitched up violently and the ship rolled
inverted to the right. My first thought was that I got hit by another
glider ... but since my searching couldn't locate another ship, I then
thought something broke. (It's amazing how time slows down in these
situations...) Entering the second rotation, I figured I was high
enough (4000')to jump, but continued to scan outside and inside and I
happened to look at my hand ... which was holding the stick just aft of
center. What, could this be a stall/spin? Opposite rudder, stick
forward, flaps to negative ... yep, recovery ... and immediately
climbing in the thermal again. I hit the tail dump switch and made a
promise to see if I could duplicate the situation when I got home ...
which I did.

Looking back, I suspect my left outside wing went through the tight
strong thermal core, which pushed the wing up, I instinctively applied
left aileron, and of course, the inside wing stalled, and the
combination of forces kinda 'snap-rolled' the ship to the right. The
spin entry from level flight and relatively violent forces disguised
the situation and delayed my recovery ... which of course is deadly at
lower altitude. So, stall/spins don't happen the way you practice them
.... although the recovery inputs taught are correct ... you just have
to execute immediately.

I now have a rule ... or mindset ... to execute stall/spin recovery
first in any situation like this. It won't help if you do indeed have
a structural or control problem ... but it is imperative avoid an
intellectual exercise if you are really in a stall/spin. As soon as
you hear yourself saying, "What the F___" ... you should be executing
stall/spin recovery.

KK


Papa3 wrote:
I agree that this is an interesting point. Even experienced, current
pilots
can be caught off guard, and perhaps a better training/recognition
method
might be in order. Maybe the yaw string can/should be a more
integral
part of the program in terms of spin recovery training?

For what it's worth, I have had a couple of unintentional spin
entries over
the last 20 years. One in particular sticks in my mind. A guy at
the
local gliderport is an experienced aerobatics competitor; he owns a
two
place Fox aerobatic glider. He asked me to go up with him one day,
since
he was having some trouble getting the Fox to climb. He figured
thermals
were a lot cheaper than 5,000 foot aerotows.

We got into a moderate thermal, and I took the controls to show him
how we
"real" soaring pilots thermal. I cranked us over to 40 degrees of
bank to
core the thermal. "Now, watch how I slow us up to really tighten
the
circle..." I said. The owner mentioned that I ought to "be a little
careful [since] stall speed at this..." He never finished the
sentence.

Departure was instantaneous. Rotation was spectacular. I recall at
first
doing everything wrong. It took me at least one full revolution to
realise
that the glider was spinning, and I think it was a couple of seconds
more
before I figured out the direction. Fortunately, we were at least
4,000
AGL at the time, and the owner just sat back and let me figure things
out.

This flight came on a day when I had been the duty instructor in the
club.
I had probably done 4 or 5 incipient spin lessons earlier in the day,
and I
probably had 40 hours flying in the preceeding 90 days. So, I was
current
and reasonably on top of my game.

This experience just reinforced the fact that the ability to
recognize a
spin, especially an unplanned one, is probably not an easy thing to
teach.
The normal training mode is thoroughly unnatural, as the student is
primed
and ready. The reality is a lot different, and I'm wondering if any
of us
emphasize the recognition aspects of the immediate post-departure
moments
enough?

Erik Mann (P3)

wrote in message
oups.com...
John,

interesting thoughts. Even with strong visual cues, the more nose
down
a spin, the more difficult it might be to surmise its direction.
Thus,
a quick reference to the yaw string is in order. Isn't the Pooch
known
for its nose down attitude while spinning?

Yet another reason to put the emphasis on stall avoidance and
prompt
recovery from prestall conditions. A suprise stall and autorotation
at
low altitude presents a great a risk, even for well trained,
heads-up
pilots.

"Apply full rudder opposite to the direction of the yaw string" -- what
does that mean? What is the direction of the yaw string? If the loose
end of the yaw string is on the right side of the canopy, is the
direction of the yaw string to the right, or is it to the left?

I think you mean that if the loose end of the yaw string is on the right
side of canopy, you apply right rudder? Or the opposite of the normal rule?




The yaw string *always* points to the inside of a spin
(according the Reichmann and others) and modifying
the teaching to 'apply full rudder opposite to the
direction of the yaw string' would be a more certain
way of choosing the life rudder pedal rather than the
death one at low altitude

At 18:30 16 January 2005, Nyal Williams wrote:
Good post, but I must point out a trap. I learned
from a student that it is easy to misunderstand which
end of the string is doing the pointing.

I always taught students to 'step on the head of the
snake.' One student could never get it right (never
been around snakes) and he was stepping on the tail
-- the aft, unattached end. I found that other students
had figured out their own way of bringing the string
into line and just ignored my comments.

We should have a conversation with students specifically
about which end of the yaw string is the pointer/tail/indicator,
etc. and which foot does what to that end of the string
under discussion.

On the other hand, perhaps my analogies are just weird.


I don't think they are weird, mine were 'kick the ball'
and 'draw the string'. Of course these days I never
have to use them that is why I remember them so well.
Isn't stepping on snakes a bit dangerous? :-)