Update on Minden tradegy

The remains of the Carat Motorglider have been placed
in its trailer and are awaiting the investigation by the NTSB
at Minden Airport.
I spoke to Larry Mansberger about the possibility of a wing
failure similar to those experienced by the Duo Discus and
the Discus CS a year or so ago. For those of you unfamiliar
to the Schempp-Hirth problems I will give you a little history.
The wings were manufactured in Eastern Europe and because
of quality assurance problems it was discovered that, after
a couple of wings disintegrated in the air, the glue used was
too thin and the parts that were expected to be glued together
had large voids where there should have been joined. This
weakened the wings causing in the air failures. Larry showed
me, using a boroscope, such defects in a Duo Discus wing
he was inspecting after the LBA and the FAA grounded
certain models of the Discus single and dual place gliders.
The Carat uses a modified std Discus wing. No problems
have ever been reported in the Carat wing. Larry helped
transport Alan's Carat back to the airport after the accident
and carefully checked to see if there were any similar
problems to those seen in the Duo's wings. There were non.
Mike More flew a Grob 103 with a student at the same time
Alan was in the air. They were also north of the airport. They
were flying above 14,000 feet, spoke of moderate turbulence,
but more importantly of the closure of layers of cloud below
them. Mike said to me that he had to be vigilant of the forming
and dissolving cloud layers and position himself so that there
was always a blue hole to get himself down in. A less
experienced pilot might not have been so aware of the dangers
of getting trapped in cloud.
Lets get the most out of this tragic accident. Lets learn and
in so doing become wiser. The wave can be a monster in more
than one sense. It can cause extreme rotor - read turbulence -
it can produce extreme lift greater than 1500 ft per minute; how
do you get down? You had better have a plan! Cloud layers can
form almost instantly - a big blue hole might disappear in
seconds. Most of the time wave is enjoyable and reasonably
safe, but it can so quickly turn into a monster. When it does
look out. Have a plan.
Copied below is an initial accident review from the US Carat
distributor.
Dave Bingham
---------------------

Date: Thu, 28 Oct 2004 04:23:53 -0000

Dear Saddened Carat Fans;

After a through investigation of the accident by AMS Flight d.o.o.,
Schempp-Hirth GmbH, Mansberger Aviation and AMS-USA it has been
determined that inflight structural failure was not the cause of this
accident.

On this flight, N418AP, went through an in flight envelope of
aproximately, a 15-20 positive G load, and an airspeed of 200+ knots.

The likely cause of the accident was a combination of high altitude
hypoxia and flying in IMC conditions, which lead to loss of control
of the aircraft and it exceeding its design limitations.

Oliver Dyer-Bennet
AMS-USA

Were the G numbers and speed found on a flight recorder?
Brian

Unfortunately Alan did not have a flight recorder.
Dave

Brian Iten wrote in message ...
Were the G numbers and speed found on a flight recorder?
Brian

At 20:06 29 October 2004, Nafod40 wrote:
Todd Pattist wrote:

I had my doubts about using this technique in a slippery
glass ship, but I found it to work fairly well, except
I use
trim back. I have tried this in my Ventus C, once
for a
total of 10,000' descent, once for 8,000' descent
and once
for 5,000' (a real waste of altitude, but each was
after a
wave flight and I was cold). I found that trim back
(thermal setting), flaps at -1 (one notch negative
- zero
and positive flap settings are limited to 80 knots),
wheel
out and brakes full open worked best. The 10,000'
and
5,000' descents were entered level, became a gentle
stable
turn and remained fairly stable with some phugoid
speed
oscillation. The turn would sometimes steepen, sometimes
shallow or even reverse.

When flying in the military, we used to play games
and see what we could
fail and still fly the plane IMC. I found I could get
by with a turn
needle, an AOA gauge, a balance ball (or a balance
string) and an ASI.
The turn needle coupled with the balance string could
be used to
maintain wings level. Basically use rudder to keep
the turn needle
centered, and wing to balance flight.

The AOA with the airspeed, oddly enough, worked fine
for pitch once you
got used to it. The AOA responded instantly to pitch
inputs, and let you
immediately correct them. From a controls standpoint,
it gave great
derivative information. The airspeed then let you dampen
the slow pitch
deviations. It was a great integrator. One could replicate
an AOA
indicator by a string on the side of a cockpit.

I could fly a PAR to mins using this technique. Tiring,
but doable.

So the turn needle is the only thing seriously lacking
in a glider.


Speak for yourself, I have a turn and slip AND a horizon
in my panel and consider them minimum equipment for
wave soaring on cloudy days in a slippery glider.

kernel.dll has caused a general protection fault, please
wait while your instrument panel reboots, would you
like to send a fault report to Microsoft?

Spinning gyro's might be passe but they don't rely
on Bill Gates flaky operating systems. I personally
don't trust Billy Boy for final glide or navigation
(I have two backups for both) never mind saving my
neck descending through cloud.

At 21:12 29 October 2004, Bill Daniels wrote:

'nafod40' wrote in message
...
Bill Daniels wrote:


You can fly with just the turn needle and ASI if
you learn to control
airspeed trends.

I'm being flip here a little bit, but I wonder if
you couldn't
manufacture an 'emergency gyro' that would be spun
up like a top by
battery, and would spin for enough minutes to hold
an attitude. Clamp it
onto the dash and start descending.


Spinning gyros are passe.
Look at: http://www.pcflightsystems.com/egyro.html
or: http://www.icarusinstruments.com/microEFIS.html

Bill Daniels

At 15:54 02 November 2004, Stefan wrote:

There is no such thing as 'trapped' by a layer if you
act
as you should.


Sounds like you haven't done much cross country wave
flying.

If you do enough cross country wave flying you will,
sooner of later, get trapped above cloud. Sometimes
you are forced to fly part of your task above 8/8 where
we fly. Other times the cloud can close quickly and
you get caught.

We were trained to position approx 1km downwind of
a known landing point using GPS (depending on terrain),
set the glider up in a stable position and open the
airbrakes at 70kts. Not desirable by any stretch of
the imagination but sometimes a required technique.

Ben Flewett wrote:

If you do enough cross country wave flying you will,
sooner of later, get trapped above cloud.

I do not agree. Know the weather. Allow yourself enough time to build
experience. Keep sharp on the development of the weather. Never, never,
never fly above a lenticularis. Keep your föhn gap in sight. Be sure
your glider can penetrate against the wind. And if in doubt, don't go.
But you knew all this before.

If you insist that getting trapped by cloud can't be avoided, then, by
all means, install at least a needle and get some training on it. You
simply can't control a slippery glass glider in cloud without a gyro.

Stefan

"Ben Flewett" wrote in message
...
At 15:54 02 November 2004, Stefan wrote:

There is no such thing as 'trapped' by a layer if you
act
as you should.


Sounds like you haven't done much cross country wave
flying.

If you do enough cross country wave flying you will,
sooner of later, get trapped above cloud. Sometimes
you are forced to fly part of your task above 8/8 where
we fly. Other times the cloud can close quickly and
you get caught.

We were trained to position approx 1km downwind of
a known landing point using GPS (depending on terrain),
set the glider up in a stable position and open the
airbrakes at 70kts. Not desirable by any stretch of
the imagination but sometimes a required technique.


I have to agree with Ben.

I got caught above a cloud deck in wave once. It wasn't that the deck
'moved in" below me, it just formed very quickly. One moment there was a
scattered lenticular deck at 22,000 and the next there was a solid deck
below me at 12,000. There was never an option to escape VFR.

Having neither radio nor gyros, I was in no hurry to try a descent either by
benign spiral or in a stable spin so I just sat there and maintained my
position in the wave. The cloud tops marked the wave nicely. After about
an hour, the patch of moisture moved off downwind and a foehn gap appeared
in the cloud deck below. Descending through the gap meant fighting my way
down through the strong lift with full spoilers in a dive. It took almost
an hour.

I'm a believer. Sooner or later, you'll need the ability to make a blind
descent.

Bill Daniels

Ben Flewett wrote:
At 15:54 02 November 2004, Stefan wrote:

There is no such thing as 'trapped' by a layer if you
act
as you should.



Sounds like you haven't done much cross country wave
flying.

If you do enough cross country wave flying you will,
sooner of later, get trapped above cloud. Sometimes
you are forced to fly part of your task above 8/8 where
we fly. Other times the cloud can close quickly and
you get caught.

We were trained to position approx 1km downwind of
a known landing point using GPS (depending on terrain),
set the glider up in a stable position and open the
airbrakes at 70kts. Not desirable by any stretch of
the imagination but sometimes a required technique.



Why downwind?

Shawn wrote in message ...
Ben Flewett wrote:
At 15:54 02 November 2004, Stefan wrote:

There is no such thing as 'trapped' by a layer if you
act
as you should.



Sounds like you haven't done much cross country wave
flying.

If you do enough cross country wave flying you will,
sooner of later, get trapped above cloud. Sometimes
you are forced to fly part of your task above 8/8 where
we fly. Other times the cloud can close quickly and
you get caught.

We were trained to position approx 1km downwind of
a known landing point using GPS (depending on terrain),
set the glider up in a stable position and open the
airbrakes at 70kts. Not desirable by any stretch of
the imagination but sometimes a required technique.



Why downwind?

Am I missing something here? If I were caught above a cloud layer, I
would go to into a spin before trying a "benign spiral". A spin is a
controlled maneuver where a spiral seems more likely to get out of
control.