Hypothetical Scenario #1 - Urgent Action required

[OneTango]

This is a voluntary pop quiz.

You're circling in a 30 degree left bank at 3000 AGL.

You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.

What do you do next? Why did the left spoiler pop open. What just happened?

To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.

My hypothetical solution and explanation follows as the next comment.

[Robert M]

First of all if it is a spoiler as on early Schweizer gliders it would be blown to the closed position.

If the drag devices you speak of are actually air brakes, as they are likely named in the POH, you have a problem.

This confusion can be deadly.

Robert Mudd
CFIA-G

On Wednesday, February 5, 2014 9:19:04 PM UTC-7, OneTango wrote:
> You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.
>
>
>
> What do you do next? Why did the left spoiler pop open. What just happened?
>
>
>
> To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.
>
>
>
> My hypothetical solution and explanation follows as the next comment.

[OneTango]

This is my best guess. I have no idea if it is correct.

>What do you do next?

Use the spoiler handle to open the right spoiler to match the left.

Follow my practiced spin recovery technique and return to level flight with both spoilers fully open.

Decide whether to land or bail out.

If there is a place that I can land with both spoilers fully open. Do that..

If I cannot make it to a field with both spoilers open, quickly determine if it is possible (and if there is less sink) to fly with one spoiler open and one spoiler closed. If it is possible, decide whether to try it or bail out.

>Why did the left spoiler pop open?

When the push rod that controls the spoilers locks past the detente, it is under compression and it is designed to bend slightly. Due to a manufacturing defect, the bent aluminum push rod rubs against the fiberglass where it passes through a wing rib (hole is not in exactly the right place or hole is not the right shape or size). Over time, the glass wing rib saws through the aluminum pushrod. At a certain point the pushrod buckles and breaks. The spoiler pops open.

[JJ Sinclair[_2_]]

On Wednesday, February 5, 2014 8:42:13 PM UTC-8, OneTango wrote:
> This is my best guess. I have no idea if it is correct.
>
>
>
> >What do you do next?
>
>
>
> Use the spoiler handle to open the right spoiler to match the left.
>
>
>
> Follow my practiced spin recovery technique and return to level flight with both spoilers fully open.
>
>
>
> Decide whether to land or bail out.
>
>
>
> If there is a place that I can land with both spoilers fully open. Do that.
>
>
>
> If I cannot make it to a field with both spoilers open, quickly determine if it is possible (and if there is less sink) to fly with one spoiler open and one spoiler closed. If it is possible, decide whether to try it or bail out.
>
>
>
> >Why did the left spoiler pop open?
>
>
>
> When the push rod that controls the spoilers locks past the detente, it is under compression and it is designed to bend slightly. Due to a manufacturing defect, the bent aluminum push rod rubs against the fiberglass where it passes through a wing rib (hole is not in exactly the right place or hole is not the right shape or size). Over time, the glass wing rib saws through the aluminum pushrod. At a certain point the pushrod buckles and breaks.. The spoiler pops open.

Your scenario #1 actually did happen in a DG-400 at Truckee about 25 years ago. One spoiler needed to be adjusted slightly, so the (non mechanic) pilot gave the quick disconnect fitting a half turn in. Under positive G force the fitting was now trying to pull away from the ball, rather than being forced into to ball. At about 4000 feet AGL, one spoiler popped full open. The pilot correctly assessed the situation and pulled the other spoiler open. Having plenty of altitude, he decided to enter the pattern to the normal glider runway (19) at 2000 feet..........thinking that extra altitude is always good, right? The extra altitude meant he had to fly farter down-wind to get rid of his excess altitude, turned final into some wind and didn't make it back to the runway! Landing short of 19 at Truckee means you hit a cliff.

If you are faced with this situation (one spoiler open), Put the ship in the middle of the longest runway available!
JJ

[[email protected]]

On Wednesday, February 5, 2014 11:19:04 PM UTC-5, OneTango wrote:
> This is a voluntary pop quiz. You're circling in a 30 degree left bank at 3000 AGL. You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed. What do you do next? Why did the left spoiler pop open. What just happened? To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies. My hypothetical solution and explanation follows as the next comment.

Dive brake became uncontrollable. It does not matter why.
Apply opposite rudder and unload the wing by neutralizing the stick in pitch while also neutralizing aileron. Open other dive brake to balance assymetrical drag that is helping add yaw in the spin.
Upon recovery, determine if the glider is controllable with one brake open. It will be in any case I would expect.
Get to landable place with one brake out(less drag than 2).
Fly a bit tighter pattern to allow for what is effectively 1/2 brake.
Go to full brakes from high final to balance and allow "normal" landing.
UH

[okko kloosterman]

I'd say you open the righthand spoiler as well, recover from the spin
(if needed) and start looking for a nice place to land you glider...

Okko (netherlands)



Op 6-2-2014 5:19, schreef OneTango:
> This is a voluntary pop quiz.
>
> You're circling in a 30 degree left bank at 3000 AGL.
>
> You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.
>
> What do you do next? Why did the left spoiler pop open. What just happened?
>
> To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.
>
> My hypothetical solution and explanation follows as the next comment.

[[email protected]]

I've been thinking this would be a fun scenario to practice on a BFR, to give the student (who will surely appreciate it) practice at handling an emergency that really isn't an emergency.

When the student checks airbrakes on his/her downwind checklist (what downwind checklist? Ah, on the second flight then!), I grab the airbrakes and say "the airbrakes just stuck open." And shut up. Now the student's job is to quickly plan a full airbrake plus slip pattern. It's not a real emergency, because we can always close the airbrakes.

Has anyone tried this? UH, font of all wisdom on such things?

John Cochrane

[Bob Whelan[_3_]]

On 2/5/2014 9:19 PM, OneTango wrote:
> This is a voluntary pop quiz.
>
> You're circling in a 30 degree left bank at 3000 AGL.
>
> You hear a thunk and the glider enters a spin. Your practiced spin
> recovery technique does not work in the usual amount of time. You look in
> the direction of the thunk and see that the left spoiler is full open, you
> confirm that the spoiler control handle is in the fully closed position. A
> quick look confirms that the right spoiler is full closed.
>
> What do you do next? Why did the left spoiler pop open. What just
> happened?

As others have said: 1) unstall the wing (reduce angle of attack/stick
forward); 2) recover from the spin/rotation (SOP per ship); 3) verify
condition; 4) (if necessary) implement "situation plan" A (or B or C,
depending on actual circumstances).

After landing - do spend a few moments congratulating yourself for being
prepared and for handling the situation correctly/safely.

This is the sort of "mental scenario playing" that can be time well spent,
indeed. Winter need not be all bad!!!

Bob W.

[Chris Nicholas[_2_]]

I agree with Otto.

The linkage has broken somewhere, sounds like between over-
centre lock (behind bulkhead) and between R and L spoiler
actuation rods.

Chris N
At 14:24 06 February 2014, okko kloosterman wrote:
>I'd say you open the righthand spoiler as well, recover from the
spin
>(if needed) and start looking for a nice place to land you glider...
>
>Okko (netherlands)

[Dan Marotta]

Try pulling the spoiler handle to get symmectrical controls. Of course,
you'll now be landing quite soon so look for a landing spot. If no good
options are available, bail out.

I'd guess a connection in the spoiler circuit for one wing failed.

"OneTango" > wrote in message
...
This is a voluntary pop quiz.

You're circling in a 30 degree left bank at 3000 AGL.

You hear a thunk and the glider enters a spin. Your practiced spin recovery
technique does not work in the usual amount of time. You look in the
direction of the thunk and see that the left spoiler is full open, you
confirm that the spoiler control handle is in the fully closed position. A
quick look confirms that the right spoiler is full closed.

What do you do next? Why did the left spoiler pop open. What just
happened?

To derive the full benefit of this exercise, you might respond to this
thread with your answer before looking at any of the other replies.

My hypothetical solution and explanation follows as the next comment.

[[email protected]]

On Thursday, February 6, 2014 11:01:32 AM UTC-5, wrote:
> I've been thinking this would be a fun scenario to practice on a BFR, to give the student (who will surely appreciate it) practice at handling an emergency that really isn't an emergency. When the student checks airbrakes on his/her downwind checklist (what downwind checklist? Ah, on the second flight then!), I grab the airbrakes and say "the airbrakes just stuck open." And shut up. Now the student's job is to quickly plan a full airbrake plus slip pattern. It's not a real emergency, because we can always close the airbrakes. Has anyone tried this? UH, font of all wisdom on such things? John Cochrane

Stuck or frozen open dive brake condition is part of our pre solo training. It does happen in the Winter.
UH

[[email protected]]

On Thursday, February 6, 2014 10:54:09 AM UTC-6, wrote:
> On Thursday, February 6, 2014 11:01:32 AM UTC-5, wrote: > I've been thinking this would be a fun scenario to practice on a BFR, to give the student (who will surely appreciate it) practice at handling an emergency that really isn't an emergency. When the student checks airbrakes on his/her downwind checklist (what downwind checklist? Ah, on the second flight then!), I grab the airbrakes and say "the airbrakes just stuck open.." And shut up. Now the student's job is to quickly plan a full airbrake plus slip pattern. It's not a real emergency, because we can always close the airbrakes. Has anyone tried this? UH, font of all wisdom on such things? John Cochrane Stuck or frozen open dive brake condition is part of our pre solo training. It does happen in the Winter. UH

Recover from the spin, land, post ship on wings and wheels.

[Eric Bick (1DB)]

On Thursday, February 6, 2014 8:01:32 AM UTC-8, wrote:
> I've been thinking this would be a fun scenario to practice on a BFR, to give the student (who will surely appreciate it) practice at handling an emergency that really isn't an emergency.
>
>
>
> When the student checks airbrakes on his/her downwind checklist (what downwind checklist? Ah, on the second flight then!), I grab the airbrakes and say "the airbrakes just stuck open." And shut up. Now the student's job is to quickly plan a full airbrake plus slip pattern. It's not a real emergency, because we can always close the airbrakes.
>
>
>
> Has anyone tried this? UH, font of all wisdom on such things?
>
>
>
> John Cochrane

I've done the "stuck open" and "stuck shut" landings for non-emergency "emergency" practice, but situations such as this fall in a bit different category and are excellent winter (or anytime) fodder for thought. Thanks. Would like to see more such. Visualizing one's actions under such conditions can help if such an actual in-flight condition occurs. I wonder if Condor can simulate such an event?
Eric Bick

[[email protected]]

All very good answers. I thought someone might mention direction of turns by now. With the one airbrake open it may be very hard to raise that wing again in a turn if it is the low side wing. Wouldn't it be wise to fly the pattern with the spoiled wing on the high side of the turns? ie - if your right airbrake is open you would want to do a left hand pattern? I would hate to get to pattern altitude and discover I can't raise my wing with the broken airbrake out after making the first turn...

Bruno -B4

[Papa3[_2_]]

On Thursday, February 6, 2014 11:54:09 AM UTC-5, wrote:
> On Thursday, February 6, 2014 11:01:32 AM UTC-5, wrote:
>
> Stuck or frozen open dive brake condition is part of our pre solo training. It does happen in the Winter.
>
> UH

Yup. Both stuck open and stuck closed patterns are in the syllabus for both initial and recurrent training at my club that does ab initio training. I also go over this in BFRs. FWIW, stuck closed (maybe never connected during assembly) is actually a much bigger issue in a typical, modern glass ship.

P3

[[email protected]]

A thought not mentioned -- is the "spin" really a spin? With one spoiler out, are you not just in an uncommanded turn, or spiral dive? Spiral dive vs. spin confusion is suggested in a few recent accident reports, and several manuals say spins will turn in to spiral dives on their own. Proper recovery depends on what is really happening.

John Cochrane

[Steve Leonard[_2_]]

On Thursday, February 6, 2014 10:01:32 AM UTC-6, wrote:
> I've been thinking this would be a fun scenario to practice on a BFR, to give the student (who will surely appreciate it) practice at handling an emergency that really isn't an emergency. When the student checks airbrakes on his/her downwind checklist (what downwind checklist? Ah, on the second flight then!), I grab the airbrakes and say "the airbrakes just stuck open." And shut up. Now the student's job is to quickly plan a full airbrake plus slip pattern. It's not a real emergency, because we can always close the airbrakes. Has anyone tried this? UH, font of all wisdom on such things? John Cochrane

I think it is an excellent thing to do, John. As you say, you always have the ability to "undo" the issue should the pilot react poorly. But, it is a really good way to assure the person is thinking about how to get where they want, and not just flying a ground track.

Steve Leonard

[Papa3[_2_]]

On Thursday, February 6, 2014 12:10:39 PM UTC-5, Papa3 wrote:
> On Thursday, February 6, 2014 11:54:09 AM UTC-5, wrote:
>
> > On Thursday, February 6, 2014 11:01:32 AM UTC-5, wrote:
>
> >
>
> > Stuck or frozen open dive brake condition is part of our pre solo training. It does happen in the Winter.
>
> >
>
> > UH
>
>
>
> Yup. Both stuck open and stuck closed patterns are in the syllabus for both initial and recurrent training at my club that does ab initio training. I also go over this in BFRs. FWIW, stuck closed (maybe never connected during assembly) is actually a much bigger issue in a typical, modern glass ship.
>
>
>
> P3

I got a PM asking why stuck closed is a bigger issue in the pattern. Briefly, because a) modern ships are not all that easy to "dirty up" with a slip and b) they will float forever in ground effect, especially with any excess speed. I routinely practiced slipping my LS4 and LS8 to landings (note: POH has a specific caution on doing this with divebrakes deployed), and it requires pretty aggressive use of rudder and a reasonable amount of "touch". I also managed to float almost the entire length of Mifflin airport (over 4,000 feet) one day with zero spoilers from about 10 feet and 55kts. That's like 400:1 including the tradeoff of 15kts or so to get down to a 40kt touchdown. For someone not prepared for the float, they could easily end up trying to force the glider on at a higher speed - see "flopping fish syndrome" and "broken gear bulkhead".

P3

[SoaringXCellence]

We actually have the stuck spoiler approach as a standard review item on our Field checkouts. I practiced several "stuck-spoiler" approaches in my training and I always have my students do it.

I think the one-out would also be a great training scenario, but both not possible or a particularly responsible thing to do.

Mike

[[email protected]]

On Thursday, February 6, 2014 3:44:05 PM UTC-5, SoaringXCellence wrote:
> We actually have the stuck spoiler approach as a standard review item on our Field checkouts. I practiced several "stuck-spoiler" approaches in my training and I always have my students do it. I think the one-out would also be a great training scenario, but both not possible or a particularly responsible thing to do. Mike

Stuck out and stuck in are both scenarios commonly used during the practical test by our local examiner.
UH

[Eric Bick (1DB)]

On Wednesday, February 5, 2014 8:19:04 PM UTC-8, OneTango wrote:
> This is a voluntary pop quiz.
>
>
>
> You're circling in a 30 degree left bank at 3000 AGL.
>
>
>
> You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.
>
>
>
> What do you do next? Why did the left spoiler pop open. What just happened?
>
>
>
> To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.
>
>
>
> My hypothetical solution and explanation follows as the next comment.

I'm still wondering, per earlier post - Condor can run simulation with brakes on or off, right? What about one on, one off? We can fly a plane with two of these three conditions as part of "emergency" practice. Don't know anyone willing to disconnect an airbrake deliberately - for practice.
Eric Bick -

[[email protected]]

On Thursday, February 6, 2014 3:29:51 PM UTC-6, Eric Bick (1DB) wrote:
> On Wednesday, February 5, 2014 8:19:04 PM UTC-8, OneTango wrote:
>
> > This is a voluntary pop quiz.
>
> >
>
> >
>
> >
>
> > You're circling in a 30 degree left bank at 3000 AGL.
>
> >
>
> >
>
> >
>
> > You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.
>
> >
>
> >
>
> >
>
> > What do you do next? Why did the left spoiler pop open. What just happened?
>
> >
>
> >
>
> >
>
> > To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.
>
> >
>
> >
>
> >
>
> > My hypothetical solution and explanation follows as the next comment.
>
>
>
> I'm still wondering, per earlier post - Condor can run simulation with brakes on or off, right? What about one on, one off? We can fly a plane with two of these three conditions as part of "emergency" practice. Don't know anyone willing to disconnect an airbrake deliberately - for practice.
>
> Eric Bick -

No Eric, and I would question the mental faculties of anyone proposing that..

[Eric Bick (1DB)]

On Thursday, February 6, 2014 1:45:46 PM UTC-8, wrote:
> On Thursday, February 6, 2014 3:29:51 PM UTC-6, Eric Bick (1DB) wrote:
>
> > On Wednesday, February 5, 2014 8:19:04 PM UTC-8, OneTango wrote:
>
> >
>
> > > This is a voluntary pop quiz.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > You're circling in a 30 degree left bank at 3000 AGL.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > What do you do next? Why did the left spoiler pop open. What just happened?
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > My hypothetical solution and explanation follows as the next comment.
>
> >
>
> >
>
> >
>
> > I'm still wondering, per earlier post - Condor can run simulation with brakes on or off, right? What about one on, one off? We can fly a plane with two of these three conditions as part of "emergency" practice. Don't know anyone willing to disconnect an airbrake deliberately - for practice.
>
> >
>
> > Eric Bick -
>
>
>
> No Eric, and I would question the mental faculties of anyone proposing that.

exactly
Eric Bick

[kirk.stant]

On Thursday, February 6, 2014 11:09:23 AM UTC-6, wrote:
> All very good answers. I thought someone might mention direction of turns by now. With the one airbrake open it may be very hard to raise that wing again in a turn if it is the low side wing. Wouldn't it be wise to fly the pattern with the spoiled wing on the high side of the turns? ie - if your right airbrake is open you would want to do a left hand pattern? I would hate to get to pattern altitude and discover I can't raise my wing with the broken airbrake out after making the first turn...

No problem - just open the other airbrake long enough to get around the turn, then close if needed.

Kirk
66

[JS]

A L'Hotellier failed on an airbrake of an LS6a in flight.
The spring failed. The LS Sleeve held everything together, so a non-event.
Jim

[kirk.stant]

On Thursday, February 6, 2014 3:10:10 PM UTC-6, wrote:

> Stuck out and stuck in are both scenarios commonly used during the practical test by our local examiner.

Are your examininees required to so no-spoiler approaches all the way to landing in glass (K-31/G-103)?

We have a debate going on in our club about the wisdom of this - our field is 2300 long, easy to use up most of that if you are a bit too fast recovering from your slip...

Now, if you are using a 2-33, no problem (more fun, actually, but not really a good emergency, either!)

As far as full-spoiler approaches, those are a fun emergency to practice.

Kirk
66

[[email protected]]

On Thursday, February 6, 2014 6:44:52 PM UTC-5, kirk.stant wrote:
> On Thursday, February 6, 2014 3:10:10 PM UTC-6, wrote: > Stuck out and stuck in are both scenarios commonly used during the practical test by our local examiner. Are your examininees required to so no-spoiler approaches all the way to landing in glass (K-31/G-103)? We have a debate going on in our club about the wisdom of this - our field is 2300 long, easy to use up most of that if you are a bit too fast recovering from your slip... Now, if you are using a 2-33, no problem (more fun, actually, but not really a good emergency, either!) As far as full-spoiler approaches, those are a fun emergency to practice. Kirk 66

We're training in 2-33's and flight tests are in same. We do slips to land in '21 and it isn't a big deal. Our field is 2700 ft. Energy management is obviously vary important.
I did slip to land in the '27. It went fine but I concluded that off airport you might as well hit the crash button on the Spot.
Interesting exchange on a scenario that I have never heard about happening.
It is obviously a long winter
UH

[[email protected]]

On Wednesday, February 5, 2014 8:19:04 PM UTC-8, OneTango wrote:
> This is a voluntary pop quiz.
>
>
>
> You're circling in a 30 degree left bank at 3000 AGL.
>
>
>
> You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.
>
>
>
> What do you do next? Why did the left spoiler pop open. What just happened?
>
>
>
> To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.
>
>
>
> My hypothetical solution and explanation follows as the next comment. First thing I do, is press opposite rudder to slow down the turn and simultaneously pull the spoiler handle and lower the nose with foward stick.

[son_of_flubber]

On Wednesday, February 5, 2014 11:19:04 PM UTC-5, OneTango wrote:

> You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed. <

Something is broken, I don't know what. So minimize compounding stress on the aircraft by using gradual and conservative control inputs.

Release back stick pressure. Open speed-limiting air brakes gradually. Gradually increase right rudder to correct yaw. Gradually pull back on stick just the minimum needed to return to level attitude, slight nose up to recover altitude and reduce speed to 55 knots (a little high to compensate for the prone to stall left wing). Slowly close right air brake and maintain level and coordinated flight. Evaluate flight characteristics. To avoid reentering the spin, do not turn left with the right airbrake closed.

Okay. Now I'm extremely stressed out. My heart rate is 180 bpm. Get a grip, calm down Flub and make better decisions.

(As I try to write up my response to this exercise, I realize that I will naturally tend to over analyze the situation. I consider too many alternate plans. I'm naturally prone to decision-paralysis. No time for that in the air.)

So. Look around for landing options. Recall knowledge of good fields. The airport might not be the best solution, even if it is relatively close.

Make a calm decision to bail out or land. If I'm in lift, consider circling to the right to gain time and altitude.

Review my options to control glide slope. 1)I can close one spoiler to reduce glide slope (compensating with rudder and aileron for left yaw and reduced left lift 2)I can open both spoilers and slip to increase glide slope 3)I can fly with both spoilers open to obtain my average glide slope. So I want to open both spoilers when I'm close to my landing spot, and adjust the shape of my pattern based on the middle glide slope.

Okay. I'm going to land. Perform pre-landing check list. What is the windsock doing? I've decided to do an extremely long final, so that I have the best chance of getting the glide angle right. This also avoids turning close to the ground in a wounded glider. I will probably enter final a little high due to the stress. Announce entering final to pattern traffic. I'm high. Open both spoilers and do a slip. Perhaps increase speed temporarily to increase sink rate. There is a crosswind coming from the left and I turned onto final too late. The drift is exaggerated by the long final. If the glide angle is good, crab to compensate for crosswind. If I'm still high, slip to compensate for the crosswind. If I'm low... S--t. I'm low, but on extremely long final and still 800 AGL. Open both spoilers and turn 90d left. There is a hayfield 200 feet lower than the airport. That is my best bet. The glide angle looks good. Announce on radio. "Landing out at hayfield to east of airport."

Land. Walk away.

So maybe it would have been better to fly an extra long base leg. That would give me plenty of time and a good picture to evaluate the glide slope. If I were high, I could fly diagonally away from the runway to make the base and final legs longer. If I were low, I could fly diagonally towards the runway to make the final shorter.

Maybe I should get some practice with full air brakes when entering downwind and adjust the pattern to compensate for the steep glide slope.

[Martin Gregorie[_5_]]

On Thu, 06 Feb 2014 16:07:26 -0800, unclhank wrote:

> On Thursday, February 6, 2014 6:44:52 PM UTC-5, kirk.stant wrote:
>> On Thursday, February 6, 2014 3:10:10 PM UTC-6,
>> wrote: > Stuck out and stuck in are both scenarios commonly used during
>> the practical test by our local examiner. Are your examininees required
>> to so no-spoiler approaches all the way to landing in glass
>> (K-31/G-103)? We have a debate going on in our club about the wisdom of
>> this - our field is 2300 long, easy to use up most of that if you are a
>> bit too fast recovering from your slip... Now, if you are using a 2-33,
>> no problem (more fun, actually, but not really a good emergency,
>> either!) As far as full-spoiler approaches, those are a fun emergency
>> to practice. Kirk 66
>
> We're training in 2-33's and flight tests are in same. We do slips to
> land in '21 and it isn't a big deal. Our field is 2700 ft. Energy
> management is obviously vary important.
> I did slip to land in the '27. It went fine but I concluded that off
> airport you might as well hit the crash button on the Spot.
> Interesting exchange on a scenario that I have never heard about
> happening.
> It is obviously a long winter UH
>
Happened at our field once. The brakes behaved themselves until the pilot
part opened them on a relatively high base leg during a normal approach
just before turning onto finals. At that point one disconnected from the
control circuit and sucked fully out. The other one remained connected to
the brake handle. The glider would fly straight with both brakes open but
not with only one out. So, once pointed at the runway, the pilot left
both open to fly straight and, as a result, landed short (wings level) in
long grass with no damage to glider or pilot.

In the circumstances I think the right decision was made.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

[[email protected]]

> Are your examininees required to so no-spoiler approaches all the way to landing in glass (K-31/G-103)?

The PTS no longer require no spoilers all the way to landing. An examiner should not be asking for it.

To go all the way to landing, it helps to stay in the slip during roundout. Fine for the pilot, very nerve wracking for instructor, as if the student decides to put it on the ground going sideways you don't have time to react..

I've found the slip to landing very educational for a totally different reason, and explaining this to students helps to "sell" an otherwise unpopular and stressful maneuver. Yes, you are very unlikely to face a spoiler failure -- and if you do, going to land somewhere a lot longer than the airport might be a better option.

The no spoiler pattern is great training to avoid all of beginner's usual mistakes, especially in high stress situations like their first off field landings. The key is to make the pattern big, and with super precise airpseed control -- not too close and too fast, like most early off field landings.

It takes a few seconds to establish slip, and it seems to take a few seconds for slip to really bite and produce a good sink rate. Hence a long final leg is key.

A big misconception is that you do it by flying a super low pattern. Actually a well established slip produces a very nice sink rate and you don't have to be low.

So selling it as "we're going to do a pattern at normal height, but nice and wide and super precise airspeed, to prepare you for off field landings" helps generate some enthusiasm,

John Cochrane

[kirk.stant]

On Thursday, February 6, 2014 9:16:48 PM UTC-6, wrote:

> The PTS no longer require no spoilers all the way to landing. An examiner should not be asking for it.

We are having a bit of an issue with that...

> To go all the way to landing, it helps to stay in the slip during roundout. Fine for the pilot, very nerve wracking for instructor, as if the student decides to put it on the ground going sideways you don't have time to react.

Nerve wracking for the next guy waiting to fly the plane, too!

> I've found the slip to landing very educational for a totally different reason, and explaining this to students helps to "sell" an otherwise unpopular and stressful maneuver. Yes, you are very unlikely to face a spoiler failure -- and if you do, going to land somewhere a lot longer than the airport might be a better option.

We actually had a G-102 spoiler handle break off inflight, resulting landing on field was long and ended up in fields past end of runway. No real other damage or injury, but could have been worse. So it can happen.

> The no spoiler pattern is great training to avoid all of beginner's usual mistakes, especially in high stress situations like their first off field landings. The key is to make the pattern big, and with super precise airpseed control -- not too close and too fast, like most early off field landings.

Ok, how do you have super precise airspeed control in a fully developed slip? Last time I tried it in glass (K-21, and my LS6) the airspeed was precisely zero!

> It takes a few seconds to establish slip, and it seems to take a few seconds for slip to really bite and produce a good sink rate. Hence a long final leg is key.

Agreed, a high long final lets you really get into that slip and drive it down to the threshold, then gives time to slow down (while still in the slip). Skill is to practice varying the speed (i.e. nose position/AOA) in the slip to control rate of sink, and be able to accurately slow down as you get close to ground, while still in slip.

>
> A big misconception is that you do it by flying a super low pattern. Actually a well established slip produces a very nice sink rate and you don't have to be low.

Bingo! We are scared of students (who may not like the slip) trying to avoid it by making the pattern flat. Bad habit, that!

> So selling it as "we're going to do a pattern at normal height, but nice and wide and super precise airspeed, to prepare you for off field landings" helps generate some enthusiasm,

Excellent point. My idea is to break it down into two parts (if using a slippery glass ship). First, using an comfortable touchdown aimpoint, fly a slipping pattern down to the preflare, then straighten out and land normally with spoilers - this to practice the slip without worrying about the landing. Next, fly a normal pattern to the threshold, but in the flare, close the spoilers and demonstrate the result of too much airspeed in ground effect and actually try to land without spoilers before running out of runway.


Kirk
66

[Dan Marotta]

Opening the functioning airbrake makes the ship symmetrical again. You've
done an "airbrake stuck open" pattern, haven't you?


> wrote in message
...
All very good answers. I thought someone might mention direction of turns
by now. With the one airbrake open it may be very hard to raise that wing
again in a turn if it is the low side wing. Wouldn't it be wise to fly the
pattern with the spoiled wing on the high side of the turns? ie - if your
right airbrake is open you would want to do a left hand pattern? I would
hate to get to pattern altitude and discover I can't raise my wing with the
broken airbrake out after making the first turn...

Bruno -B4

[Kimmo Hytoenen]

Open the (right) spoiler and try spin recovery.
Maybe left spoiler actuating rod got loose.

At 04:19 06 February 2014, OneTango wrote:
>This is a voluntary pop quiz.
>
>You're circling in a 30 degree left bank at 3000 AGL.
>
>You hear a thunk and the glider enters a spin. Your practiced
spin
>recover=
>y technique does not work in the usual amount of time. You
look in the
>dir=
>ection of the thunk and see that the left spoiler is full open,
you
>confirm=
> that the spoiler control handle is in the fully closed position. A
quick
>l=
>ook confirms that the right spoiler is full closed. =20
>
>What do you do next? Why did the left spoiler pop open.
What just
>happene=
>d?
>
>To derive the full benefit of this exercise, you might respond to
this
>thre=
>ad with your answer before looking at any of the other replies.
>
>My hypothetical solution and explanation follows as the next
comment.
>

[Don Johnstone[_4_]]

>Op 6-2-2014 5:19, schreef OneTango:
>> This is a voluntary pop quiz.
>>
>> You're circling in a 30 degree left bank at 3000 AGL.
>>
>> You hear a thunk and the glider enters a spin. Your practiced spin
>recovery technique does not work in the usual amount of time. You look
in
>the direction of the thunk and see that the left spoiler is full open,
you
>confirm that the spoiler control handle is in the fully closed position.
A
>quick look confirms that the right spoiler is full closed.
>>
>> What do you do next? Why did the left spoiler pop open. What just
>happened?
>>
>> To derive the full benefit of this exercise, you might respond to this
>thread with your answer before looking at any of the other replies.
>>
>> My hypothetical solution and explanation follows as the next comment.
>
Deploy the other spoiler/airbrake. It is unlikely that the ailerons/rudder
will have the authority to counteract the rolling/yawing moment produced by
a single deployment. Normal spin recovery to approach attitude/speed. With
both spoilers deployed you are still flying a glider, I concede that it is
a glider with a crap gliding angle but if you have ever flown a primary you
will be right at home. You can fly a normal circuit (pattern) with the
normal rules for a glide angle that you now have. It may be wise to ensure
that you do not go any further downwind than the boundary of your selected
landing area, depending on length available, but again the normal rules
apply.

[HGXC[_3_]]

On Saturday, February 8, 2014 6:02:56 AM UTC-5, Don Johnstone wrote:
> >Op 6-2-2014 5:19, schreef OneTango:
>
> >> This is a voluntary pop quiz.
>
> >>
>
> >> You're circling in a 30 degree left bank at 3000 AGL.
>
> >>
>
> >> You hear a thunk and the glider enters a spin. Your practiced spin
>
> >recovery technique does not work in the usual amount of time. You look
>
> in
>
> >the direction of the thunk and see that the left spoiler is full open,
>
> you
>
> >confirm that the spoiler control handle is in the fully closed position.
>
> A
>
> >quick look confirms that the right spoiler is full closed.
>
> >>
>
> >> What do you do next? Why did the left spoiler pop open. What just
>
> >happened?
>
> >>
>
> >> To derive the full benefit of this exercise, you might respond to this
>
> >thread with your answer before looking at any of the other replies.
>
> >>
>
> >> My hypothetical solution and explanation follows as the next comment.
>
> >
>
> Deploy the other spoiler/airbrake. It is unlikely that the ailerons/rudder
>
> will have the authority to counteract the rolling/yawing moment produced by
>
> a single deployment. Normal spin recovery to approach attitude/speed. With
>
> both spoilers deployed you are still flying a glider, I concede that it is
>
> a glider with a crap gliding angle but if you have ever flown a primary you
>
> will be right at home. You can fly a normal circuit (pattern) with the
>
> normal rules for a glide angle that you now have. It may be wise to ensure
>
> that you do not go any further downwind than the boundary of your selected
>
> landing area, depending on length available, but again the normal rules
>
> apply.

Heck I've flown Hang Gliders for 38 years so you simply fly it as a trainer -:)

[BruceGreeff]

Similar failure happened on a Nimbus 4DM some years ago - on a fast
final glide into Gariep.

Height was low, speed was high (well past Vmo) when they hit a powerful
thermal.
Wings took the shock, but one airbrake actuator failed under the shock
load. It had been damaged by "buzzing" over an extended period - the
caps were not held down properlyso the blade would chatter in it's box
on pull ups. This set up fatigue in the connecting rod which snapped
under the sudden whip motion on the wing.

Due to high speed, no spin departure.
The resulting yaw caused an immediate roll toward the open brake wing.
Pilot correctly assessed the situation, opened the other airbrake and
attempted to recover from the inadvertent barrel roll.
Attempt was unsuccessful, wings failed symmetrically at the outer panel
join, and then a couple of metres from the root - conveniently
preserving the failed actuator and the witness marks... Calculated
failure somewhere on the far side of 300km/h and enormous g.

Fuselage impact was a couple of seconds later - both pilots being
ejected many metres from the point of impact.
Being a DM the resulting fire destroyed much of the confetti that
remained. Somehow, enough of one of the three loggers remained for a
trace to be obtained.

Moral of that story is - check your airbrake actuators for wear and
fatigue - particularly on long flexible wings. And have some respect for
the numbers - they are there for a reason.

Time from initial failure to impact was maybe 30s. Think about how fast
you can close the distance to the ground next time you are at 250km/h
and 600 feet height.
That height is the distance you are travelling in three seconds (70m/s).

Bruce


On 2014/02/06 4:02 PM, JJ Sinclair wrote:
> On Wednesday, February 5, 2014 8:42:13 PM UTC-8, OneTango wrote:
>> This is my best guess. I have no idea if it is correct.
>>
>>
>>
>>> What do you do next?
>>
>>
>>
>> Use the spoiler handle to open the right spoiler to match the left.
>>
>>
>>
>> Follow my practiced spin recovery technique and return to level flight with both spoilers fully open.
>>
>>
>>
>> Decide whether to land or bail out.
>>
>>
>>
>> If there is a place that I can land with both spoilers fully open. Do that.
>>
>>
>>
>> If I cannot make it to a field with both spoilers open, quickly determine if it is possible (and if there is less sink) to fly with one spoiler open and one spoiler closed. If it is possible, decide whether to try it or bail out.
>>
>>
>>
>>> Why did the left spoiler pop open?
>>
>>
>>
>> When the push rod that controls the spoilers locks past the detente, it is under compression and it is designed to bend slightly. Due to a manufacturing defect, the bent aluminum push rod rubs against the fiberglass where it passes through a wing rib (hole is not in exactly the right place or hole is not the right shape or size). Over time, the glass wing rib saws through the aluminum pushrod. At a certain point the pushrod buckles and breaks. The spoiler pops open.
>
> Your scenario #1 actually did happen in a DG-400 at Truckee about 25 years ago. One spoiler needed to be adjusted slightly, so the (non mechanic) pilot gave the quick disconnect fitting a half turn in. Under positive G force the fitting was now trying to pull away from the ball, rather than being forced into to ball. At about 4000 feet AGL, one spoiler popped full open. The pilot correctly assessed the situation and pulled the other spoiler open. Having plenty of altitude, he decided to enter the pattern to the normal glider runway (19) at 2000 feet..........thinking that extra altitude is always good, right? The extra altitude meant he had to fly farter down-wind to get rid of his excess altitude, turned final into some wind and didn't make it back to the runway! Landing short of 19 at Truckee means you hit a cliff.
>
> If you are faced with this situation (one spoiler open), Put the ship in the middle of the longest runway available!
> JJ
>

--
Bruce Greeff
T59D #1771

[JJ Sinclair[_2_]]

On Saturday, February 8, 2014 12:35:58 PM UTC-8, BruceGreeff wrote:
> Similar failure happened on a Nimbus 4DM some years ago - on a fast
>
> final glide into Gariep.
>
>
>
> Height was low, speed was high (well past Vmo) when they hit a powerful
>
> thermal.
>
> Wings took the shock, but one airbrake actuator failed under the shock
>
> load. It had been damaged by "buzzing" over an extended period - the
>
> caps were not held down properlyso the blade would chatter in it's box
>
> on pull ups. This set up fatigue in the connecting rod which snapped
>
> under the sudden whip motion on the wing.
>
>
>
> Due to high speed, no spin departure.
>
> The resulting yaw caused an immediate roll toward the open brake wing.
>
> Pilot correctly assessed the situation, opened the other airbrake and
>
> attempted to recover from the inadvertent barrel roll.
>
> Attempt was unsuccessful, wings failed symmetrically at the outer panel
>
> join, and then a couple of metres from the root - conveniently
>
> preserving the failed actuator and the witness marks... Calculated
>
> failure somewhere on the far side of 300km/h and enormous g.
>
>
>
> Fuselage impact was a couple of seconds later - both pilots being
>
> ejected many metres from the point of impact.
>
> Being a DM the resulting fire destroyed much of the confetti that
>
> remained. Somehow, enough of one of the three loggers remained for a
>
> trace to be obtained.
>
>
>
> Moral of that story is - check your airbrake actuators for wear and
>
> fatigue - particularly on long flexible wings. And have some respect for
>
> the numbers - they are there for a reason.

Very interesting report, we had a Nimbus 4DM come apart at Minden and both pilots were killed several years back. They got into a death spiral for unknown reasons..............wonder if one spoiler could have popped open to start the spiral? The accident report stated that both spoilers deployed when the ship was near vertical, but now I'm wondering if one was open before the other? I have seen instances where one spoiler came out caused by bending of its pushrod or flexing of drive unit in the root rib, but nothing broke! Would the accident investigator notice a bent rod or flexed root rib in a pile of fiberglass rubble?
JJ

[[email protected]]

In one of the early replies, One Tango mentioned the bending of the pushrod and rubbing on the fibreglass "rib." I have seen this but rather than a rib, it was the opening into the spoiler boxes on an SZD Junior. The thin fibreglass of the opening was rubbing on the pushrod and sawing through it like a hacksaw. It was happening primarily on one wing with the other side just starting to leave a mark. We discovered it because there was a problem with this aircraft where one spoiler would open at a slightly before the other so we tried adjusting it to get them to open and close at the same time as well as open to the same height. We started this process because the spoilers did not seem to want to stay locked and as we tested it noticed they were not actuating at the same time. Adjustment required removal of the pushrods and that was when we found it. A review of the logbooks showed that the aircraft had an accident early in its life and one wing was replaced with a brand new one. As the investigation continued, we also found that the pushrod actuating gears were "crunchy" on the original wing but smooth on the other new wing and when we pulled it out of the wing (not an easy task but can be done through an opening in the root rib) we could find no damage but they did not feel right. These gears do not have bearings so the initial thought was not the problem. I was able to discover online that there was a fatality when a Junior spun in after one spoiler opened. The conclusion was that the teeth on the nylon-like gears had sheared off. It may be that the tolerances were such that they did not mesh properly or it was a material fault. We decided to order a new gear set along with the a replacement pushrod. However, none of this explained the differing operation of the spoilers that was the cause of our initial investigation. In the end, we figured out that when the wing was replaced, the fittings had been improperly installed in the torque tube in the fuselage. Accuracy is very important. When a wing is replaced, the collars that are installed on the torque tube do not come predrilled. You have to fit the wing, mark the place where the holes are to be drilled from inside the fuselage and then take it apart and install the collars (anyone who has assembled a Polish glider knows what these are.) Anyway, we finally solved the problem after installing new collars on both sides, a new pushrod and a new gear set.

So, a real lesson here. An accident, an inaccurately installed new wing fitting, the wrong pressure on the pushrods to try to get them adjusted so they would lock (just barely), the resulting rubbing on the spoiler boxes that was swing the pushrods. Aircraft was flown like that for 10 plus years. Finally a new aircraft mechanic said he would not sign it off because it didn't feel right (but he didn't know what the problem was.) A lot of hours spent three aircraft mechanics and myself to discover and then resolve each of the issues described above. Now the aircraft is finally correct. Had the new aircraft mechanic not exercised a high degree of caution to start the process in the first place, it was only a matter of time (maybe many years, maybe soon) where the pushrod on the new wing or the gear set on the old wing would have failed, that is if an accident wasn't first caused by the spoilers popping open.

As an aside, it appears that two things happened around the same time: the fatality when the gear set failed and a change in the company that manufactured the Junior. Whatever the cause, the newer gear sets appear to be made of a different material than the old ones. The old ones were a white plastic and the new ones are black. I would suggest anyone with a Junior look to see what they have, keep an eye on it and inspect the lateral rear sides of the pushrods where they enter the spoiler box. It is tricky to do because if you pull the spoiler up to peek in, the pushrod is pulled deeper into the wing but with a small mirror or an inspection camera it likely can be done. The alternative is to remove the pushrod which is a pain because it is really hard to remove and replace the attachment inside the wing blind at the root end.

[Bill T]

Stuck open airbrakes? Why yes we have!
On the Grob, a good strong arm can hold against the student trying to close the spoiler. Once he realizes he can't close the spoilers and declares the problem and turns toward the airport, the emergency is resolved. Spoiler control is given back to effect a safe final touch down.
BillT

[Don Johnstone[_4_]]

At 22:07 09 February 2014, Bill T wrote:
>Stuck open airbrakes? Why yes we have!
>On the Grob, a good strong arm can hold against the student trying to
>close=
> the spoiler. Once he realizes he can't close the spoilers and declares
>the=
> problem and turns toward the airport, the emergency is resolved. Spoiler
>c=
>ontrol is given back to effect a safe final touch down.
>BillT

a good strong arm and mechanical advantage

[Dale Watkins]

On Thursday, February 6, 2014 10:01:32 AM UTC-6, wrote:
> I've been thinking this would be a fun scenario to practice on a BFR, to give the student (who will surely appreciate it) practice at handling an emergency that really isn't an emergency.
>
>
>
> When the student checks airbrakes on his/her downwind checklist (what downwind checklist? Ah, on the second flight then!), I grab the airbrakes and say "the airbrakes just stuck open." And shut up. Now the student's job is to quickly plan a full airbrake plus slip pattern. It's not a real emergency, because we can always close the airbrakes.
>
>
>
> Has anyone tried this? UH, font of all wisdom on such things?
>
>
>
> John Cochrane

We do this exercise at Sky soaring every year with pilots - some have to close the spoilers to make it back. Debrief is interesting.
Zen

[flgliderpilot[_2_]]

On Wednesday, February 5, 2014 11:19:04 PM UTC-5, OneTango wrote:
> This is a voluntary pop quiz.
>
>
>
> You're circling in a 30 degree left bank at 3000 AGL.
>
>
>
> You hear a thunk and the glider enters a spin. Your practiced spin recovery technique does not work in the usual amount of time. You look in the direction of the thunk and see that the left spoiler is full open, you confirm that the spoiler control handle is in the fully closed position. A quick look confirms that the right spoiler is full closed.
>
>
>
> What do you do next? Why did the left spoiler pop open. What just happened?
>
>
>
> To derive the full benefit of this exercise, you might respond to this thread with your answer before looking at any of the other replies.
>
>
>
> My hypothetical solution and explanation follows as the next comment.

Probably late to the game, but I'd open the other spoiler to match and then plan to land.. unless of course I discover the left aileron is also not working...