Crunch Alert (USA) - hugely serious but (apparently) non-fatal

Having once 'felt the need' myself, this one undoubtedly has a compelling
story; it will definitely make its way into the NTSB database.

Thank goodness the pilot is (reportedly) OK. SSA member; diamond badge; 2-time
3rd place finisher in Region 9 Regional.

If it happens it must be possible. Let's - as pilots - do what we can to
minimize our chances of 'it' happening...

Begin cut-n-paste...
IDENTIFICATION
Regis#: 555AP Make/Model: JS1 Description: JONKER SAILPLANE
Date: 04/29/2012 Time: 1900

Event Type: Accident Highest Injury: None Mid Air: N Missing: N
Damage: Unknown

LOCATION
City: TAOS State: NM Country: US

DESCRIPTION
PILOT ENCOUNTERED RUDDER PEDAL PROBLEM, LOST CONTROL, AND ABANDONED THE
AIRCRAFT BY PARACHUTE.

INJURY DATA Total Fatal: 0
# Crew: 1 Fat: 0 Ser: 0 Min: 0 Unk:
# Pass: 0 Fat: 0 Ser: 0 Min: 0 Unk:
# Grnd: Fat: 0 Ser: 0 Min: 0 Unk:

WEATHER: K0E0 291855Z AUTO 23006KT 10SM SCT075 21/01 A3004

OTHER DATA


FAA FSDO: ALBUQUERQUE, NM (SW01) Entry date: 04/30/2012

End cut-n-paste...

From Albuquerque Soaring web site...

"Per Billy Hill this evening: today Angel Pala was thermalling with Billy in the area north of Moriarty and south of Lamy when he heard a loud bang, and lost rudder authority (both pedals fell full forward). Evidently the glider behaved like full right rudder. Shortly thereafter the glider entered an inverted spin, and Angel wisely decided he should walk home, and so hit the silk. He landed under parachute, and hiked out, and was taken to a hospital in Santa Fe. He seems to be fine and Billy expects to pick him up when he is released from hospital.

Mike

On Apr 30, 1:21*pm, Mike the Strike wrote:
From Albuquerque Soaring web site...

"Per Billy Hill this evening: today Angel Pala was thermalling with Billy in the area north of Moriarty and south of Lamy when he heard a loud bang, and lost rudder authority (both pedals fell full forward). Evidently the glider behaved like full right rudder. Shortly thereafter the glider entered an inverted spin, and Angel wisely decided he should walk home, and so hit the silk. He landed under parachute, and hiked out, and was taken to a hospital in Santa Fe. He seems to be fine and Billy expects to pick him up when he is released from hospital.

Mike

Happy that all is well with the pilot..

But do we know what happened? a mid air? a rudder cable failure?

T

On Apr 30, 7:28*pm, T wrote:
On Apr 30, 1:21*pm, Mike the Strike wrote:

From Albuquerque Soaring web site...

"Per Billy Hill this evening: today Angel Pala was thermalling with Billy in the area north of Moriarty and south of Lamy when he heard a loud bang, and lost rudder authority (both pedals fell full forward). Evidently the glider behaved like full right rudder. Shortly thereafter the glider entered an inverted spin, and Angel wisely decided he should walk home, and so hit the silk. He landed under parachute, and hiked out, and was taken to a hospital in Santa Fe. He seems to be fine and Billy expects to pick him up when he is released from hospital.

Mike

Happy that all is well with the pilot..

But do we know what happened? a mid air? a rudder cable failure?

T

It was not a mid-air. We are awaiting more information on the
investigation. The good news is that.Angel is now home and is
recovering from his bumps and bruises after landing, via parachute, in
Nowhere, NM........
Thx - 3R

On Monday, April 30, 2012 7:46:35 PM UTC-7, Renny wrote:
On Apr 30, 7:28*pm, T wrote:
On Apr 30, 1:21*pm, Mike the Strike wrote:

From Albuquerque Soaring web site...

"Per Billy Hill this evening: today Angel Pala was thermalling with Billy in the area north of Moriarty and south of Lamy when he heard a loud bang, and lost rudder authority (both pedals fell full forward). Evidently the glider behaved like full right rudder. Shortly thereafter the glider entered an inverted spin, and Angel wisely decided he should walk home, and so hit the silk. He landed under parachute, and hiked out, and was taken to a hospital in Santa Fe. He seems to be fine and Billy expects to pick him up when he is released from hospital.

Mike

Happy that all is well with the pilot..

But do we know what happened? a mid air? a rudder cable failure?

T

It was not a mid-air. We are awaiting more information on the
investigation. The good news is that.Angel is now home and is
recovering from his bumps and bruises after landing, via parachute, in
Nowhere, NM........
Thx - 3R

Wow, thank god it happened at altitude!
Isn't it that virtually all our rudder pedals mechanism are spring loaded, and if one cable breaks the result is instantaneously full rudder? I always thought this is a receipt for disaster. A glider without rudder control may still be flyable and even landable, but not with full rudder!

Ramy

Wow, thank god it happened at altitude!
Isn't it that virtually all our rudder pedals mechanism are spring loaded,
and if one cable breaks the result is instantaneously full rudder? I always
thought this is a receipt for disaster. A glider without rudder control may
still be flyable and even landable, but not with full rudder!

Ramy

Some powered aircraft have interconnected controls with springs in the
control circuits. Tailwheel birds with steerable tailwheels have springs
connecting the rudder and tailwheel. A broken cable on those aircraft
can result in a rudder hard over. My homebuilt taildragger has a fixed
tailwheel for that reason (and enough rudder to drag that wheel sideways
when needed)

I think most gliders do not have springs in the rudder control circuit.
I can't remember ever flying a glider with a spring-centered rudder.
However, don't we all fly with just a little pressure on both rudder
pedals? A cable break is going to result in the rudder hard over on the
unbroken side. That is going to result in a rapid yaw and air loads that
will tend to hold the rudder hard over with no way to get it back. I can
see that putting the ship over on it's back pretty quickly. Snap rolls
anyone?

Originally Posted by Ramy

Renny wrote:[color=blue][i]

Wow, thank god it happened at altitude!
Isn't it that virtually all our rudder pedals mechanism are spring loaded, and if one cable breaks the result is instantaneously full rudder? I always thought this is a receipt for disaster. A glider without rudder control may still be flyable and even landable, but not with full rudder!

Ramy

This is sort of true, but not in this case. The spring is just strong enough to ensure the pedal does not fall forward when the pilot climbs out. Also, if one spring is off, it is not strong enough to allow yaw to initiate.

In the accident of the JS1, the glider was in a right hand slip (full left aileron required). We can assume in this case that the left hand rudder cable broke. In the accident photo’s the right hand cable is off, which probably happened during impact.

On Monday, April 30, 2012 4:21:08 PM UTC-4, Mike the Strike wrote:
From Albuquerque Soaring web site...

"Per Billy Hill this evening: today Angel Pala was thermalling with Billy in the area north of Moriarty and south of Lamy when he heard a loud bang, and lost rudder authority (both pedals fell full forward). Evidently the glider behaved like full right rudder. Shortly thereafter the glider entered an inverted spin, and Angel wisely decided he should walk home, and so hit the silk. He landed under parachute, and hiked out, and was taken to a hospital in Santa Fe. He seems to be fine and Billy expects to pick him up when he is released from hospital.

Mike

What was the altitude AGL ?
Where is the JS1 rudder vented ?

Sure lucky it ended OK for the pilot !
Best Regards, Dave

Reportedly, the problem occurred at about 5,000 ft AGL and the aircraft inverted and entered a flat spin. Angel departed the aircraft about 3,500 to 3,800 feet AGL.

Mike

I've often wondered about the amount of altitude loss that occurs when exiting an aircraft in distress. Here it was about 1,500 feet in what would seem to be ideal circumstances - inverted (I have no idea what part centrifugal force was playing in this case).

Doesn't bode well for someone in a deep cockpit in an upright attitude. Maybe it's time to look seriously at DG's NOAH system...

-John

On Tuesday, May 1, 2012 9:42:52 AM UTC-4, Mike the Strike wrote:
Reportedly, the problem occurred at about 5,000 ft AGL and the aircraft inverted and entered a flat spin. Angel departed the aircraft about 3,500 to 3,800 feet AGL.

Mike