Glider crash near Reno yesterday

At 05:13 28 September 2018, 2G wrote:
On Thursday, September 27, 2018 at 8:58:23 PM UTC-7, James
Betker wrote:
I've got a question - let's assume that the speculation going on
here is
=
right and that the elevator control was locked in a full nose-high
station
=
- what is the optimal thing to do if you are ever faced with this?
Am I
rig=
ht in assuming that it is to bail as quickly as possible before you
start
b=
uilding G-loads which would make bailing impossible? If you
somehow got
you=
rself into a scenario where you were endlessly looping the glider,
would
de=
ploying full airbrakes bleed enough energy to stop the looping
(and maybe
i=
nduce a spin instead)?
=20
This is certainly a nightmare scenario. My condolences go out to
the
frie=
nds and family of the departed.

If you are being subjected to 10 g's it would be very difficult to
raise
yo=
ur arm to pull the handle - your 10 lb arm suddenly becomes 100
lb.

Tom




I am posting this for a second time but you should all watch it.
https://www.youtube.com/channel/UCvO...NoSro7U5LkED-Q

It answers some of the questions but not why the Duo failed.

Years ago my brother was involved in a midair collision in his ventus. The other glider ran into his elevator jamming it into a full up position. The ship took him for a series of high speed loops with him attempting to eject. The G load prevented the canopy from seperating, my bro was able to get his feet free to kick out the canopy and get over the side. Speaking with him after the fact, he said if he had to do it again, he would have tried to aileron roll so the G load would have ejected him instead of pinning him in the cockpit.

Le vendredi 28 septembre 2018 10:05:31 UTC+2, a écritÂ*:
Years ago my brother was involved in a midair collision in his ventus. The other glider ran into his elevator jamming it into a full up position. The ship took him for a series of high speed loops with him attempting to eject. The G load prevented the canopy from seperating, my bro was able to get his feet free to kick out the canopy and get over the side. Speaking with him after the fact, he said if he had to do it again, he would have tried to aileron roll so the G load would have ejected him instead of pinning him in the cockpit.

If the glider is looping, you can't decrease the g-loads without the use of the elevator. Putting aileron will just transform it into a barrel row. G-loads are the same, but the wings will break earlier.

At 10:47 28 September 2018, Tango Whisky wrote:
Le vendredi 28 septembre 2018 10:05:31 UTC+2,
a
=C3=A9c=
rit=C2=A0:
Years ago my brother was involved in a midair collision in his
ventus.
T=
he other glider ran into his elevator jamming it into a full up
position.
T=
he ship took him for a series of high speed loops with him
attempting to
ej=
ect. The G load prevented the canopy from seperating, my bro was
able to
ge=
t his feet free to kick out the canopy and get over the side.
Speaking
with=
him after the fact, he said if he had to do it again, he would have
tried
=
to aileron roll so the G load would have ejected him instead of
pinning
him=
in the cockpit.

If the glider is looping, you can't decrease the g-loads without the
use
of=
the elevator. Putting aileron will just transform it into a barrel row.
G-=
loads are the same, but the wings will break earlier.


What am I missing here? Why can't the glider be maneuvered into
something like a constant 80 degree bank turn? Then pull out the
dive brakes to slow it down and reduce G available? As the speed
bleeds off, reduce bank angle to let the nose float up and slow down
more. Then, jump out before the thing stalls and starts spinning.
Get the vertical gravity vector out of the picture so that the speeds
don't accelerate like they might on the back side of a loop. 10 G's?
For how long? I pulled 9+ G's on many occasions in the F-16, and to
sustain it for any length of time required full afterburner which a
DUO doesn't have.
RO

On Friday, September 28, 2018 at 9:15:05 AM UTC-4, Michael Opitz wrote:
At 10:47 28 September 2018, Tango Whisky wrote:
Le vendredi 28 septembre 2018 10:05:31 UTC+2,
a
=C3=A9c=
rit=C2=A0:
Years ago my brother was involved in a midair collision in his
ventus.
T=
he other glider ran into his elevator jamming it into a full up
position.
T=
he ship took him for a series of high speed loops with him
attempting to
ej=
ect. The G load prevented the canopy from seperating, my bro was
able to
ge=
t his feet free to kick out the canopy and get over the side.
Speaking
with=
him after the fact, he said if he had to do it again, he would have
tried
=
to aileron roll so the G load would have ejected him instead of
pinning
him=
in the cockpit.

If the glider is looping, you can't decrease the g-loads without the
use
of=
the elevator. Putting aileron will just transform it into a barrel row.
G-=
loads are the same, but the wings will break earlier.


What am I missing here? Why can't the glider be maneuvered into
something like a constant 80 degree bank turn? Then pull out the
dive brakes to slow it down and reduce G available? As the speed
bleeds off, reduce bank angle to let the nose float up and slow down
more. Then, jump out before the thing stalls and starts spinning.
Get the vertical gravity vector out of the picture so that the speeds
don't accelerate like they might on the back side of a loop. 10 G's?
For how long? I pulled 9+ G's on many occasions in the F-16, and to
sustain it for any length of time required full afterburner which a
DUO doesn't have.
RO

I hear you, Mike and I think your and the other suggestions are all good and valid but hardly any of the folks in the glider community have flown a F16 or similar hardware or are trained for these type of high g-maneuvers. I didn't know either of the crew but would assume they were at an advanced age, i.e. not the fittest and strongest to work their way out of the seat under that high g-load.
Then there is the 'oh-crap - now what' delay since whatever happened was way out of the ordinary and the correct - or any reaction - does take time to formulate and execute. If the g-load built quickly, the seating position in a Duo will not allow one to remain conscious for long and we typically don't wear anti-g flight suits to combat the effects.
Remember the Reno Air Race accidents a few years back, where a P51 got pulverized on the apron? Pictures showed the pilot slumped over unconscious and he was used to higher loads encountered in these races.
One can only hope that the Duo-crew was 'out of it' when they hit the ground. R.I.P!

Uli
'AS'

Le vendredi 28 septembre 2018 15:15:05 UTC+2, Michael Opitz a écritÂ*:
What am I missing here? Why can't the glider be maneuvered into
something like a constant 80 degree bank turn? Then pull out the
dive brakes to slow it down and reduce G available? As the speed
bleeds off, reduce bank angle to let the nose float up and slow down
more. Then, jump out before the thing stalls and starts spinning.
Get the vertical gravity vector out of the picture so that the speeds
don't accelerate like they might on the back side of a loop. 10 G's?
For how long? I pulled 9+ G's on many occasions in the F-16, and to
sustain it for any length of time required full afterburner which a
DUO doesn't have.
RO

Michael, you are probably right that on the top of the loop, you may try to use aileron and rudder to shift the loop into an high-bank turn. This turn would still have a high g-load, and opening the airbrakes at 80 deg bank would still put the wings beyond ultimate stress load (which is 40% lower than with airbrakes closed).
But then - you'd have to perform this manoeuver a second after you have blacked out at the lower part of the loop. During my early aerobatic training I once blacked out (with the instructor in the back seat) 45 deg nose up because I had relaxed my respiration to early, and it took me a couple of seconds to come around and understand what's happening - during this time, the glider had proceeded through the loop to 20 deg nose down (and it wasn't intended to be a loop).
So if the description of the eye whitnesses is correct, I think that the situation was not survivable, and I join Uli in his wish that by then, the crew was out of it.

Still frightening that such a situation might develop out of the blue.

Bert TW

Unfortunately positive G is positive whether you're upside down or right
side up.Â* In the inverted position you'll have the benefit of the
earth's gravity subtracting 1 G from the total, but getting over the
cockpit rail from the semi reclined position in the cockpit will still
be very difficult.Â* On the positive side, at the top of the loop, the G
loading will be significantly less due to the reduced airspeed resulting
from the climb.Â* In the actual situation I don't know if one would
recognize this and plan his bail out at the top of the loop.Â* Most
glider pilots have no experience with aerobatics or high G situations...

On 9/28/2018 2:05 AM, wrote:
Years ago my brother was involved in a midair collision in his ventus. The other glider ran into his elevator jamming it into a full up position. The ship took him for a series of high speed loops with him attempting to eject. The G load prevented the canopy from seperating, my bro was able to get his feet free to kick out the canopy and get over the side. Speaking with him after the fact, he said if he had to do it again, he would have tried to aileron roll so the G load would have ejected him instead of pinning him in the cockpit.

--
Dan, 5J

On Thursday, September 27, 2018 at 12:01:38 PM UTC-7, wrote:
I agree that this appears to be an elevator failure. What pieces of the wreckage were retrieved? Was the horizontal stabilizer/elevator retrieved? Was the elevator bolt located (ripped out of the elevator, found in a side pocket, found in the trailer, etc). I have the ability to fly my Phoenix low level over the site on a suitable light east wind day and do a close search for the horizontal stab if it is missing. Finding the stab may be the key to solving this tragedy.


Maybe a tool left under the seat, which eventually jammed the elevator? A close inspection of the burned out wreckage may reveal any unusual metal tool.

Thinking through this further and again, one would have to have this
planned out in advance...Â* At the top of the loop, the airspeed will be
considerably lower than at the bottom.Â* So, at the top, one could
perform a half roll (an Immelmann turn), and, since the glider would now
be upright at lower airspeed, it would begin a climb but would stall
near or before reaching vertical.Â* This would result in near zero G and
would be an ideal time to bail out.Â* It might even result in negative G
which would make all the easier.

The half roll could even be done past the top of the loop (half Cuban
Eight).Â* Again, the glider would start to climb but would not have the
energy yet to complete a loop, making bail out rather easy.Â* BUT...Â*
being unprepared for the first high G maneuver, the pilot(s) could
simply be unconsious...

I hope I never get the chance to prove this right or wrong.

On 9/28/2018 9:16 AM, Tango Whisky wrote:
Le vendredi 28 septembre 2018 15:15:05 UTC+2, Michael Opitz a écritÂ*:
What am I missing here? Why can't the glider be maneuvered into
something like a constant 80 degree bank turn? Then pull out the
dive brakes to slow it down and reduce G available? As the speed
bleeds off, reduce bank angle to let the nose float up and slow down
more. Then, jump out before the thing stalls and starts spinning.
Get the vertical gravity vector out of the picture so that the speeds
don't accelerate like they might on the back side of a loop. 10 G's?
For how long? I pulled 9+ G's on many occasions in the F-16, and to
sustain it for any length of time required full afterburner which a
DUO doesn't have.
RO
Michael, you are probably right that on the top of the loop, you may try to use aileron and rudder to shift the loop into an high-bank turn. This turn would still have a high g-load, and opening the airbrakes at 80 deg bank would still put the wings beyond ultimate stress load (which is 40% lower than with airbrakes closed).
But then - you'd have to perform this manoeuver a second after you have blacked out at the lower part of the loop. During my early aerobatic training I once blacked out (with the instructor in the back seat) 45 deg nose up because I had relaxed my respiration to early, and it took me a couple of seconds to come around and understand what's happening - during this time, the glider had proceeded through the loop to 20 deg nose down (and it wasn't intended to be a loop).
So if the description of the eye whitnesses is correct, I think that the situation was not survivable, and I join Uli in his wish that by then, the crew was out of it.

Still frightening that such a situation might develop out of the blue.

Bert TW


--
Dan, 5J

On an ASK 21, a half roll takes 6 seconds, and I wouldn't expect a Duo to roll any faster.