How Low to Spin??

Kirk Stant wrote:

(which probably takes a bit more than one second, I would think) will
corkscrew the nose down and around, but you are not flying backward!

I agree. I don't think I am flying backward. I think I am,
to some degree, flying backward. What I mean is that some of the momentum
carrying me into the spin will cause a reduction of airspeed
which is most pronounced at 180 degrees from the entry heading.

including Maverick's F-14 spinning out to sea after
departing over the desert - I would have loved to have seen that for
real!)

Art Scholl lost his life in a fatal inverted spin into the Pacific
Ocean with no parachute (while filming for Top Gun).
Some say the weight of the cameras on the wingtips made the
spin unrecoverable...

Still a bad analogy, in my opinion. Think of the snap roll example -
at what point do you stop "rolling" and start "frisbeeing"? You
don't, your flightpath just curves more downward as you initiate the
spin slower.

At the 180 snap-roll point from entry, the nose isn't pointing in the other
cardinal direction. It simply isn't comparable.

It sure would be fun to take up a nice spinning glider (a 2-32 for
example), instument it, then take turns trying to make each other
sick!

Hmmm...on a calm wind day with a cheap GPS with a time track
set to every 1 second, if the GPS is synchronised with a
stopwatch and observer, it may get interesting. A
logger might do the same...

But don't you ever wonder why the most nose down part of a positive
spin is at the 1/2 spin point? Lowest airspeed perhaps? And
why IS that...

Broken glass ships have the same problem with weight in the tail...
G-103s are notorious for it. Othewise, instruments, batteries,
cheeseburgers, and beer tend to move the CG forward.

You have a BBQ and beer cooler in the nose? How inventive...
I suppose your landouts are quite a party...

Again, the aft CG doesn't cause the spin, it just make it easier to
initiate, and maybe harder to recover.

NASA thought it sometimes made it easier, and sometimes
harder to recover, depending on the aircraft. Go figure.

You still have to exceed the
stalling AOA, regardless of CG location. Winch launching is probably
a lot safer overall than aerotowing (from my limited experience in
Germany), with fewer potential gotcha's - plus it's really hard to
kill the winch operator (unless you crash on the winch, of course).

I must say it's a LOT of fun teaching aerotow. Formation flight
where you don't have to worry about airspeed is a real thrill for
a lot of folks. But yep, aerotow might be more complicated...
But I wouldn't know, I've never done a wench launch...

are not really "max performance" turns, and are usually no more than
90 - 100 degrees (unless you prefer the 180 degree one turn to final
approach, which I do).

I do rectangular bases, so others know I'm landing instead of
thermalling at the end of the runway :PPP

Well, most glider landing accidents only break the glider, or maybe a
bush or two - and the reasons are usually pretty consistent.

Shoulder harnesses probably have brought the stats down a
huge amount, and the lower stall speed, and fuselage shape,
of gliders compared to, say a Cherokee. Trike landing gear and
rough fields do not mix...

Not necessarily - the key is the lack of outside references, coupled
with moving the head too much so as to confuse the inner ear.

In an aileron roll, the head is moved. In max dutch rolls
45 to 45, the head is moved. So again, I guess you are agreeing with
me that high roll rates and steep banks can induce vertigo.
If you don't agree. Take a pax at night cover all instruments.
Head perfectly straight ahead. Close eyes. Then max roll rate
left 45 bank, then 90 degrees of turn, slow roll right,
and tell them to open eyes while level and recover. Fun, huh?

And yes, lack of coherent outside reference is important too.
Pretty easy to get when looking at clouds and fog and mountainsides...
And sometimes tough to correct without...
wait for it...moving your head

I have had the leans in
formation in cloud - interesting when you pop out and your internal
gyros cage up!

I've had them almost uncontrollably on several occasions, night IMC,
and straight and level on a rollout to a heading.
Absolutely bloodcurdling...

I fly my pattern based on where I want to touch down, and adjust the
pattern accoding to my altitude and the wind. I prefer low, tight,
fast patterns, so I can see what I'm getting into during a landout!
It helps that my glider can get rid of a lot of energy fast when I
need to.

The only disadvantages I can find of very effective spoilers a

1) If they ain't locked for takeoff, a gnarly pio
2) If they don't have very fine controls, hard to be precise
about glide slope.
3) If at max out, landing flare is VERY fast, and stall speed
increased
--

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

(Mark James Boyd) wrote in message news:412eb379$1@darkstar...

You have a BBQ and beer cooler in the nose? How inventive...
I suppose your landouts are quite a party...

You bet!

In an aileron roll, the head is moved. In max dutch rolls
45 to 45, the head is moved. So again, I guess you are agreeing with
me that high roll rates and steep banks can induce vertigo.
If you don't agree. Take a pax at night cover all instruments.
Head perfectly straight ahead. Close eyes. Then max roll rate
left 45 bank, then 90 degrees of turn, slow roll right,
and tell them to open eyes while level and recover. Fun, huh?

No, I do not agree with you that high roll rates and steep banks
induce vertigo. It's the disconnect between what you see, and what
the inner ear feels, that causes vertigo. If you can see the horizon,
then as long as you don't make a sudden movement of your head in a
"wrong" direction (which depends on which way the plane is moving"),
you should not experience vertigo. But close your eyes, or fly into a
cloud, and even a small roll or pitch rate can induce vertigo. Unless
you are thermalling with your eyes closed (reminds me of some pilots I
know!) or in a cloud (not common in the US), vertigo should not be a
problem in a glider, no matter how fast you roll or steep you turn.
Now, I will caveat that statement with the observation that it is
possible to trigger vertigo in some individuals by a sudden (and I
mean unusually rapid) head movement at the same time as the plane is
rolling - and that should be taught to pilots, just like IFR pilots
are shown how lack of outside references can lead to vertigo. But you
shouldn't be jerking your head around while flying!

And yes, lack of coherent outside reference is important too.
Pretty easy to get when looking at clouds and fog and mountainsides...
And sometimes tough to correct without...
wait for it...moving your head

You don't need a lot of outside references to maintain your attitude -
but yes (as I say above), when you lose outside references, you are
vulnerable to vertigo. But to get a glider into a situation where
there are no useful outside references is a bad thing.

The only disadvantages I can find of very effective spoilers a

1) If they ain't locked for takeoff, a gnarly pio
2) If they don't have very fine controls, hard to be precise
about glide slope.
3) If at max out, landing flare is VERY fast, and stall speed
increased

1. Use a checklist. Oh, and why is the tow pilot fanning his rudder
at me?
2. G-103s are horrible in this respect. Most gliders are fine.
3. You don't have to land with them all the way out, but it's nice to
have the option.

Kirk

Kirk Stant wrote:

1) If they ain't locked for takeoff, a gnarly pio

1. Use a checklist. Oh, and why is the tow pilot fanning his rudder
at me?

LOL! "use a checklist."
Kind of covers everything, huh?

"Oh yeah? He had an accident? I bet he
didn't use the checklist!"

everyone nods solemnly in agreement, and the
speaker passes Leadership 101 for saying the most obvious,
non-controversial thing anyone can think of

ROFL! Man, I remember my MEI and his checklists.
We added so much stuff, I think there was
something about taking our pulse and blood pressure
in the runup to ensure we weren't overstressed
for the flight. Oh, and zipper check and
make sure we had chewing gum in case ATC gave us a
real fast descent. I think we had to taxi back for
fuel one time because we'd drained the tanks in
the runup area doing the checklist.

But hey, Kirk, I'm just teasin ya'. Just one of my
pet peeves, the checklist with the important
points buried.

How about just three critical safety items in the PW-5:

1. Airbrakes locked
2. Trim forward
3. Belts on tight

I'm a big fan of the prioritized checklist.
Do the three most important items first.
Do the nine most important items next.
Do the 27 most important items next.
Do the 81 most important items next.
And so on...

To figure out what the priority list should be, I
follow this advice:

You should learn from the mistakes of others, because you?ll
never have enough time to make all those mistakes yourself.
--- Ben Franklin

So I scour the accident reports, and see what killed
other pilots, and put that at the top three. Then I see
what caused non-fatal accidents, and put that in the
next 6-9. Then I add in the stuff from the
factory checklist. Then I add the piddly stuff that just
prevents a nuisance (vent closed to avoid dust, for example,
or towrope attached. It's hard for me to imagine why
an unattached towrope would be a safety hazard

Despite my best efforts, I've found myself getting sleepy
after the 45th item on the checklist. So this has worked
best for me.
--

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

That means that the NTSB can add to the accident report:
1. Failed to use proper check list.

Along with my favorite:
2. The aircraft had not filed a flight plan.

As in: A sharp wind blew up and destroyed the properly secured glider
while the operator was home in bed. The operator had NOT filed a flight
plan.

The NTSB finds the probable cause to be the Pilot's failure to use a proper
check list and file a flight plan. Contributing factors were the 100 knot
wind and the fact that the pilot was home in bed at the time of the
accident.

Allan

"Mark James Boyd" wrote in message
news:412fa9ba$1@darkstar...
Kirk Stant wrote:

1) If they ain't locked for takeoff, a gnarly pio

1. Use a checklist. Oh, and why is the tow pilot fanning his rudder
at me?

LOL! "use a checklist."
Kind of covers everything, huh?

... Snip ...

ADP wrote:
1. Failed to use proper check list.
2. The aircraft had not filed a flight plan.

3. Pilot failed to maintain proper terrain clearance.

everyone nods heads solemnly in agreement with
the wise sage who figured this one out too
--

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

We have a pilot/owner where I fly that has this tidbit as the first item on
his takeoff checklist:
1. Remove canopy cover
8)
-Bob

"Mark James Boyd" wrote in message
news:41310ed8$1@darkstar...
ADP wrote:
1. Failed to use proper check list.
2. The aircraft had not filed a flight plan.

3. Pilot failed to maintain proper terrain clearance.

everyone nods heads solemnly in agreement with
the wise sage who figured this one out too
--

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

On Fri, 27 Aug 2004 21:38:02 UTC, (Mark James
Boyd) wrote:

: "Oh yeah? He had an accident? I bet he
: didn't use the checklist!"

I once had someone try to persuade me to use a checklist for a winch
cable break. Yes, great, run through a list of actions which have to
be started within a second and completed within a few ... the idiot's
an instructor now, and feedback tells me that he's no less of an
idiot...


Ian


--

"Ian Johnston" wrote in message news:cCUlhtvFIYkV-pn2-8OXf57VN35wC@localhost...
On Fri, 27 Aug 2004 21:38:02 UTC, (Mark James
Boyd) wrote:

: "Oh yeah? He had an accident? I bet he
: didn't use the checklist!"

I once had someone try to persuade me to use a checklist for a winch
cable break. Yes, great, run through a list of actions which have to
be started within a second and completed within a few ... the idiot's
an instructor now, and feedback tells me that he's no less of an
idiot...

I recently read the accident report of the ASW20 crash (fatal) at
Williams, CA. Per the check list, they did a positive control check of
the elevator by having the assistant (co-owner) hold the elevator
while the pilot applied force on the stick. Resistance was felt, check
list passed. Only problem was the elevator was not hooked up and what
the pilot felt was the push rod hitting the bottom of the elevator.
Now, if the guy just LOOKED at the connection it would have been
obvious that it was not hooked up (it is in plain site).

Still, he had a second chance to save himself. When the glider decided
to launch itself he could have immediately released and delt with the
situation at a more survivable attitude (the tow pilot released him
instead).

Check lists are not substitutes for plain common sense. If you use
them, do another walk around the glider without the list, looking for
things you might have missed. Following a list may give you tunnel
vision. A DC-9 was landed gear up by two experienced pilots following
a check list (they missed one step). They were so certain that they
had done everything right that they ignored the lack of the sound and
thump of the gear lowering (common sense, again).

Tom

(Tom Seim) wrote in message . com...

I recently read the accident report of the ASW20 crash (fatal) at
Williams, CA. Per the check list, they did a positive control check of
the elevator by having the assistant (co-owner) hold the elevator
while the pilot applied force on the stick. Resistance was felt, check
list passed. Only problem was the elevator was not hooked up and what
the pilot felt was the push rod hitting the bottom of the elevator.
Now, if the guy just LOOKED at the connection it would have been
obvious that it was not hooked up (it is in plain site).

Tom and all,

Your report triggers my a "Pavlov's dog" reaction in me. Rather than
salivating like the dog I shake my head in sorrow that in the US we
are practicing placing the pilot in the cockpit for a positive control
check. If the pilot in your example had done the walk-around combined
with the PCC he would most likely have noticed the disconnected
elevator. In most other countries (input from Europe, Australia, S.
Africa etc. welcome) they put a helper at the controls (in the
cockpit) and the pilot asks for specific movements i.e. 'elevator full
up, elevator full down' with the helper repeating the words and
applying force to the controls. I have talked about this to many
pilots here in the US including instructors and the reaction was
always that most here think the pilot needs to "feel" the controls
from the cockpit to know what's going on. I think that's incorrect
mainly because different helpers will apply different forces to the
control surfaces leading to inconsistent feedback.
Another observation in the same vein: most US pilots fail to do the
walk-around check with the justification that they just taped wings
and tail and looked over the glider while doing so.
Another comment: poking fun at the use of check-lists in this thread
is very unfortunate.

Herb, J7

On Tue, 31 Aug 2004 14:08:05 UTC, (Herbert
Kilian) wrote:

: In most other countries (input from Europe, Australia, S.
: Africa etc. welcome) they put a helper at the controls (in the
: cockpit) and the pilot asks for specific movements i.e. 'elevator full
: up, elevator full down' with the helper repeating the words and
: applying force to the controls.

The general custom in the UK seems to be to do positive control checks
with the pilot in the cockpit at, or just before, the launch point. I
like this, myself, as the tow across the field gives loose things a
good chance to fall off. At least one club I have flown at - following
a fatal accident - requires the PCC to be noted in the flying log
before a launch is given. This seems a thoroughly sound idea to me.

In the unfortunate case described, the error seems to have been in
assuming that a connection which can push can also pull.

I am all against over dependence on check lists and, in particular,
against using them to replace airmanship. However, I can't see how the
accident in question can be blamed on check list use. It would seem to
be due to a mixture of a) rigging error b) poorly carried out control
check and c) poor training in rigging and carrying out control checks.

Ian