Nelson Funston

On May 8, 7:59*am, "noel.wade" wrote:
On May 8, 7:38 am, wrote:

Any Idea what caused the accident?

There are lots of ideas - but blind rumor and speculation at this
point don't help anything.

The best thing to do is take this as a reminder to ALWAYS be safety-
conscious when involved with a glider operation.

Take care,

--Noel

Now this will help us all avoid the same mistakes...
Aviation is full of unexplained fatal accidents which we can only
speculate, but at least we can hope to learn from those who survived.
I hope we don't need to wait for the NTSB report, we all know what
they worth. Or Thelen's accident reports in Soaring Magazine, which
from some reason he can never get the details from those involved, and
have to speculate.
I wish Nelson speedy recovery.

Ramy

FAA initial report:

IDENTIFICATION
Regis#: 747JN Make/Model: 4M Description: SCHEMP-HIRTH
NIMBUS-4M
Date: 05/04/2008 Time: 2122

Event Type: Accident Highest Injury: Minor Mid Air: N
Missing: N
Damage: Substantial

LOCATION
City: EPHRATA State: WA Country: US

DESCRIPTION
AIRCRAFT ON TAKEOFF ROLL, WING STRUCK THE PAVEMENT AND THE AIRCRAFT
CARTWHEELED, EPHRATA, WA

In somewhat of a contradiction to the FAA report, newspaper and
eyewitness accounts state that the glider was on initial climb after
takeoff and was at 40 or 50 feet when it experienced an uncontrolled
roll. Extreme deflection of the wings on impact reportedly reduced
the damage and injuries.

Mike

On May 8, 6:34 pm, Mike the Strike wrote:
FAA initial report:

IDENTIFICATION
Regis#: 747JN Make/Model: 4M Description: SCHEMP-HIRTH
NIMBUS-4M
Date: 05/04/2008 Time: 2122

Event Type: Accident Highest Injury: Minor Mid Air: N
Missing: N
Damage: Substantial

LOCATION
City: EPHRATA State: WA Country: US

DESCRIPTION
AIRCRAFT ON TAKEOFF ROLL, WING STRUCK THE PAVEMENT AND THE AIRCRAFT
CARTWHEELED, EPHRATA, WA

In somewhat of a contradiction to the FAA report, newspaper and
eyewitness accounts state that the glider was on initial climb after
takeoff and was at 40 or 50 feet when it experienced an uncontrolled
roll. Extreme deflection of the wings on impact reportedly reduced
the damage and injuries.

I think that "uncommanded" roll might be more precise than
"uncontrolled", for technical reasons.

The newspaper account said, "He noted the airport changed its
operational procedure and added obstacles on the ramp. While not the
cause, Funston said, 'It was certainly a complicating factor'."

For mental exercise, let's forget about this particular accident for a
moment and review the possiblities based on these 2 scraps of
information: uncommanded roll and new obstacles.

Let's think about the range of possibilities:
First, we can assume that it's an accident, hence something
unpredicted happened.
Therefore, what caused the upset was either unpredictable or
considered unlikely.
A: Causes of aircraft flight accidents fall into just 3 categories:
1: Something about the a/c "broke" (in the broadest sense,
including linkages not sufficiently connected)
2: Something about the pilot "broke" (again, in the broadest sense,
including natural failures of perception, which we call 'illusion.')
3: Something about the air was "broken" (again, broadly, especially
including vortices = turbulence).

There is one component of this situation that is invisible: the air.
Its motions become apparent only when dust or smoke are swept along.
Then we're aware of remarkable turbulence, which must occur when it's
windy.

Any time there is a strong wind, complex vortices are shed by
obstacles, which persist for a long distance downwind relative to the
height of the obstacle. I was years ago taught a rule of thumb that
amounts to a 1:60 ratio of height to persistence. By this rule, a 15-
foot obstacle would cause turbulence that persisists 300 yards
downwind along a plateau.

Now, anytime the wings of an aircraft experience different winds, a
roll moment will be induced. This does not require either wing to be
stalled!

For example, a friend rolled his helicopter up into a ball a few years
ago. He was crop-dusting in nearly -still air, and flew head on into a
dust devil. His airfoils obviously experienced dramatic differences
in airflow, and a dramatic uncommanded roll occurred, and in a second,
he was surrounded by wreckage, forturnately unhurt.

For another example, a man was flying a single-engine a/c to landing
in a 20-kt crosswind last November. The instructor pilot watching on
the ground said that the airplane was level at 40 ft, when it abruptly
rolled almost to vertical, struck a tip, cartwheeled, crashed inverted
an burned. All 4 occupants died.

For another example, a friend, a commercial pilot, was landing his SEL
in gusty winds last year, and as he prepared to flare, it suddenly
felt as though his left wing had suddenly lost lift. He managed to
avoid a tip-strike and accident.

Why do our wings rock when we fly through gusty winds? because the
wings experience rapid local changes in airspeed and AOA in
dimensions smaller than the wingspan. Might sometimes this be
sufficient to cause a snap roll? Why not?

I write this not to analyze Mr. Funston's accident, but because the
concepts of "uncommanded roll" and "new obstacle" inspire me to remind
fellow soaring pilots that windy conditions are always accompanied by
significant turbulence close to the ground, exacerbated by nearby
obstacles. This turbulence is invisible, and can indeed roll our
aircraft enough to cause a tip strike or loss of control.

Dan Johnson
Menomonie, WI

Others have noted...

FAA initial report:

IDENTIFICATION
Regis#: 747JN Make/Model: 4M Description: SCHEMP-HIRTH
NIMBUS-4M
Date: 05/04/2008 Time: 2122

Event Type: Accident Highest Injury: Minor Mid Air: N
Missing: N
Damage: Substantial

LOCATION
City: EPHRATA State: WA Country: US

DESCRIPTION
AIRCRAFT ON TAKEOFF ROLL, WING STRUCK THE PAVEMENT AND THE AIRCRAFT
CARTWHEELED, EPHRATA, WA

In somewhat of a contradiction to the FAA report, newspaper and
eyewitness accounts state that the glider was on initial climb after
takeoff and was at 40 or 50 feet when it experienced an uncontrolled
roll. Extreme deflection of the wings on impact reportedly reduced
the damage and injuries.

I think that "uncommanded" roll might be more precise than
"uncontrolled", for technical reasons.

The newspaper account said, "He noted the airport changed its
operational procedure and added obstacles on the ramp. While not the
cause, Funston said, 'It was certainly a complicating factor'."

For mental exercise, let's forget about this particular accident for a
moment and review the possiblities based on these 2 scraps of
information: uncommanded roll and new obstacles.

Good, thoughtful stuff snipped...

Where this thread has gone is - to me - an excellent example of how
*thoughtful* speculation (perhaps it is better described as
"imagination") may wisely be used to enhance one's own safety when
soaring. No need to wait for the (too often, hopelessly homogenized)
NTSB reports...

Respectfully,
Bob - no fan of off-the-wall speculation -W.

On May 13, 12:44*pm, Bob Whelan
wrote:
DESCRIPTION
* AIRCRAFT ON TAKEOFF ROLL, WING STRUCK THE PAVEMENT AND THE AIRCRAFT
CARTWHEELED, EPHRATA, WA

In somewhat of a contradiction to the FAA report, newspaper and
eyewitness accounts state that
snipped

I think that "uncommanded" roll might be more precise than
"uncontrolled", for technical reasons.

Good, thoughtful stuff snipped...

Where this thread has gone is - to me - an excellent example of how
*thoughtful* speculation (perhaps it is better described as
"imagination") may wisely be used to enhance one's own safety when
soaring. *No need to wait for the (too often, hopelessly homogenized)
NTSB reports...

Respectfully,
Bob - no fan of off-the-wall speculation -W.-


What a nice thread in response to a sad situation.
Sorry Nelson was hurt, hope he recovers well.

I am very glad to see the shift from "let's not talk 'til a report is
written"
toward a "let's consider possibilities and see how I could avoid
similar scenarios." That is the most productive view to take
following
any breakage, human, airframe or atmospherically.

That was also the total gist of my presentation at the ABQ Convention,
titled "What the NTSB will Never Say About 2007 Fatalities."

Keep after this concept folks. It helps build mental flexibility
which I believe is vastly undertrained in glider cockpits.

Cindy B

Another fan of constructive speculation for personal-use accident-
analysis
www.caracolesoaring.com

Another fan of constructive speculation for personal-use accident-
analysis

Hey Cindy,

If you're a fan of constructive speculation, here's a good one for you
to chew on; I'd welcome your observations.

On Sunday 5/11, a routine pattern at Turf turned into a nightmare on
final approach when I ran into 20+ knot sink. This was one or two
heartbeats after I had deployed spoilers upon judging my altitude to
still be a bit too high. I pulled the brakes back in as soon as I felt
the glider going into freefall, but the sink persisted and I soon
found myself wondering if I could clear the power lines.

Of course, faced with a very serious question of whether I could clear
power lines, I assumed I could not. I turned hard left choosing to
deal with mesquite bushes instead, and hit the ground hard before I
could complete the turn. (That told me that the score would have been
power lines One, tuno Zero.)

As I look back at the incident, which mangled a brand new ASG 29, I
ask myself, as anyone would, what I could have or should have done
different. (Begin Monday morning quarterbacking.) I really can't
identify much. The pattern was textbook, the altitude and IAS good. I
would normally have chosen a little more IAS in the pattern but I was
conscious of a pair of 2-33's landing in front of me so I stuck with
60 knots indicated. Winds were about 10 knots steady right down the
runway.

Very thankful, all the same, to be walking, talking and departing for
Moriarty in high spirits tomorrow morning.

~ted/n2O

On May 15, 10:13*pm, Tuno wrote:
Another fan of constructive speculation for personal-use accident-
analysis

Hey Cindy,


If you're a fan of constructive speculation, here's a good one for you
to chew on; I'd welcome your observations.

On Sunday 5/11, a routine pattern at Turf turned into a nightmare on
final approach when I ran into 20+ knot sink
snip
As I look back at the incident, which mangled a brand new ASG 29, I
ask myself, as anyone would, what I could have or should have done different.

As I look back at the incident, which mangled a brand new ASG 29, I
ask myself, as anyone would, what I could have or should have done
different.

I was giving a field check to a new (rated) club member and after we
turned final i remarked "nice, perfect height, perfect distance". Five
seconds later I couldn't see the rwy because of the tree tops above us.
The only thing that saved our bacon was that we had enough speed to make
the rwy.

Reminds me of a story of where a Shorts pilot hit a micro burst on
approach and fire walled the throttles - mandating a very expensive
teardown and inspection of the engines. At the "inquest", he was asked
"why did you push the engines to 120% of their rated power"? The
response was "because I couldn't push them higher".

Tony V.

On Thu, 15 May 2008 21:28:40 -0700 (PDT), CindyASK
wrote:


That was also the total gist of my presentation at the ABQ Convention,
titled "What the NTSB will Never Say About 2007 Fatalities."

Another fan of constructive speculation for personal-use accident-
analysis


I'd love to read it!
can you please send it to me?
thank you very much

Aldo Cernezzi
www.voloavela.it
nauta
-at-
email.it

danlj wrote:

I write this not to analyze Mr. Funston's accident, but because the
concepts of "uncommanded roll" and "new obstacle" inspire me to remind
fellow soaring pilots that windy conditions are always accompanied by
significant turbulence close to the ground, exacerbated by nearby
obstacles. This turbulence is invisible, and can indeed roll our
aircraft enough to cause a tip strike or loss of control.

While this does not invalidate what Dan says, pilots may be interested
to know the "obstacle" was basically flags marking changes in the
runway, and would not affect the wind on the runway. They did add some
distraction for the pilot, however, as it was his first launch since the
new runway was marked on a portion of the ramp. Previously, the entire
width of the ramp was "available". My guess is the distraction was a
much bigger factor than the wind.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
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