Fatal Glider Accident in SZD-55 Junior

[RatherBeFlying]

I witnessed this accident in August 2007. The Canada Transportation Safety board is about to release their report and I have posted my own observations and analysis at SoaringCanada.riq.ca :: View topic - August 2007 Junior Fatal Accident (http://soaringcanada.riq.ca/viewtopic.php?p=17635#17635)

There are factors that first time pilots need to know and I see that there's 27 Juniors in the UK.

[BackPacker]

Interesting stuff. I wish I had known about this before going solo in the junior.

Bookmarked for later review. Thanks.

[gpn01]

My feeling is that anyone who has limited experience on type should ensure a thorough briefing by an instructor who is current on type. Comments such as "twisting the wrist" on the airbrake lever suggests a different setup to any of the Juniors that I've flown in the UK. Ditto "I make a point of setting the trim and altimeter before getting in the Junior" is inconsistent with pre-takeoff checks as taught in the UK - the trim is set as part of the CBSIFTCBE process. This avoids the risk of the trim being set and then being knocked into a different position as the pilot climbs in. In fact, thinking about it, many of the Juniors I've flown have fairly loose trim detentes which mean that if the trim is set fairly forward or backwards then it'll leap out of the position when the elevator is fully deflected as part of the CBSIFTCBE check. This is usually accompanied by a bang as the trimmer leaps through the gate, or a quiet 'twang' noise as the trim breaks (something that I've found notoriously weak on Juniors).

[x933]

Though my recollection of the Junior is hazy, I do remember that pulling any more than half airbrake meant you had to invert your grip on the handle or you bashed your elbow on the back of the seat (which was rather uncomfortable, as I remember).

I never liked flying it, it felt like the guys at SZD went round the parts bin of pretty much every other manufacturer and grabbed a different lump of the aircraft, which resulted in an unholy bastardisation of aircraft that though light and soared well, felt like a toy with a heavy elevator, feel-less ailerons and a trimmer that bit you if it was in a bad mood. A good first plastic aircraft as long as you were well briefed, if you could fly it fairly well (spot landing it was a walk in the park, mahoosive airbrakes) you were fine in anything with a bit more grunt.

[RatherBeFlying]

My habit of setting the trim and altimeter before getting in is in addition to the normal pre-takeoff checklist once inside. It means I have to goof up twice instead of just once;)

[tinpilot]

...and I see that there's 27 Juniors in the UK.Yeah, but training over here emphasises the importance of using plenty of airbrake on approach. Students are taught to arrange their circuit and approach to use about two thirds airbrake. Altering airbrake settings after starting to round out is discouraged.

The pre-flight brief for a check flight prior to single seat conversion should point out that a sensible approach, using at least half airbrake, is a pre-requisite if the pilot is to be allowed to fly the single seater. The pre-flight brief before flying the single seater should again include a reminder to arrange the approach so that the pilot uses plenty of airbrake.

The pilot should be strapped into the glider for a cockpit familiarisation session before the glider is put into the launch queue. This should include checking for full & free movement on all the controls, including airbrakes.

I don't see how opening the airbrakes could pitch the glider 45 degrees nose down unless either the pilot pushed the stick forward or, possibly, the glider stalled.

Obviously I haven't read the TSB report but from what I've read in your Soaring Canada post, the main lessons from this accident are not glider specific but more to do with pre solo training and post solo supervision.


ps the thread title refers to an SZD-55 which, as you know, is a different glider.

[Mark1234]

Again, with junior experience; there is a pitch down with the airbrakes (unusual), and yes it takes a while for them to start to open. Never had a problem with them unlocking, but the trim plunger spring locking mechanism isn't great; I always manually 'assisted' the spring to ensure that it locked properly. On one occasion it did pop out and shoot to one end over a bump at the end of the takeoff run - I contemplated bunging off, but it seemed to be flying OK, so spent the first 500ft following the tug, mentally reviewing bail out options and wondering what fell off; a bit further up I figured out what the problem was! Personally I'd think that would be more of an issue for a novice pilot than the brakes.

To my mind the biggest 'difference' about the junior on being introduced to it as a first single seat glass ship was it's relatively brick like characteristics especially compared to an AS K21, and the immense descent rate with brakes. We were indeed briefed thoroughly, and took a high tow with airbrake familiarisation recommended on the way down.

In short, I don't believe there's anything inherently bad about the junior; this sounds rather like an unfortunate accident and an overwhelmed pilot.

[cats_five]

Think the various comments in the thread are spot-on - the Junior is a simple robust glider that is fun, and which early solo pilots at my club seem very happy flying. I wouldn't say it's brick-like compared to a K21 though - it's best L/D is given as 35 at 80kph, the K21 is given as 34 at 85-90kph.

Obviously if you fly the Junior too fast then it does turn into a brick - but so does the K21.

As tinpilot says, briefing is all when converting an early solo pilot from a dual-seat trainer to a single-seater, be it a Junior, K8 or something else. I was sat in it away from the launch line, the various other folks trying to offer advice were sent away (we did ask the previous pilot where he had set the trimmer for takeoff), and what was expected was clear since it was a circuits day. (In fact I had to wait 6 weeks for a soaring flight in one!)

BTW I have very similar hours and flights in a Junior to RatherBeFlying and I still fly them from time to time although I have my own glider now.

[Mark1234]

I wouldn't say it's brick-like compared to a K21 though - it's best L/D is given as 35 at 80kph, the K21 is given as 34 at 85-90kph.

Fair enough - I always felt (subjectively) that on approach / at approach speeds it seemed a steeper profile, and in any breeze far more important to keep the base leg close. Been a while tho..

[cats_five]

Fair enough - I always felt (subjectively) that on approach / at approach speeds it seemed a steeper profile, and in any breeze far more important to keep the base leg close. Been a while tho..

Bigger airbrakes. And you can always put them away if necessary.

[RatherBeFlying]

I've noticed that spoilers cracked open on the Junior give a descent slope similar to a Blanik with half spoiler.

A student transitioning will tend to position the final turn at the same point and height as he is used to doing with the two seater and use not very much spoilers to maintain that slope.

[cats_five]

I've noticed that spoliers cracked open on the Junior give a descent slope similar to a Blanik with half spoiler.

A student transitioning will tend to position the final turn at the same point and height as he is used to doing with the two seater and use not very much spoilers to maintain that slope.

He/she should be briefed against that. As commented earlier, in the UK we are taught to use 1/2 to 2/3 airbrakes on finals - once that is we are close enough to the field to open them. If you open them all the way it will descend very steeply (especially with a bit of headwind), but that's not a problem so long as the reference point is a reasonable distance into the field (it should be further in in strong winds or if there is wind shear, and early solo pilots shouldn't be trying to creep in over the hedge), plus of course getting the speed control right is important.

IMHO the Junior really isn't a scary difficult glider to fly. So long as they have been spinning our early solo pilots are converted to a Junior as soon as the instructor thinks they are ready (which can be before they have done 10 solo flights), and I'm not aware of any wildly over-exciting first flights in them. Did see someone balloon (more powerful elevator than a K21) but they sorted it out just fine.

BTW there are 10 Blaniks on the UK register, 29 Grob 103s, 80 K21s and 102 K13s, so flying a Blanik is a very much a rarity in the UK.

[gpn01]

My habit of setting the trim and altimeter before getting in is in addition to the normal pre-takeoff checklist once inside. It means I have to goof up twice instead of just once;)

If a check becomes part of a habit it stops being a check. There ARE some things where it's advisable to check before getting into a glider - seat position, ballast weights and rudder pedal position (not applicable in the case of the Junior where it's much easier to adjust them once you're in the glider).

Anything that you 'check' twice actually increases the risk of you not doing it all because the brain eventually goes into an internal dialogue of "I'll be checking that again in a minute..." followed by "....I've checked that already". That's why in the UK CBSIFTCBE covers each item once and only once.

[Mark1234]

A student transitioning will tend to position the final turn at the same point and height as he is used to doing with the two seater and use not very much spoilers to maintain that slope.

That may be a teaching difference - UK side, I was definitely taught to aim for a half brake to 2/3 approach early on final, and if that was low to put them away, move up on the profile and get them out again, NOT to carry a crack of airbrake all the way down, precisely because that sets up a different round out and hold off experience each time.

Bigger airbrakes. And you can always put them away if necessary.
No kidding :) What I thought I said in my first comment was that an approach (I assumed flown with plenty of airbrake, as I was taught), in a junior is somewhat steeper than a comparable glider (k21) - I used the phrase brick like. Not an issue, was briefed on it, but that was as I said, the main 'different' thing about the junior in my experience.

[cats_five]

Ah - thought you were refering to the Junior's general flying characaristics which certainly are not brick-like! (but you can make a K21 into a final approach brick with side slip plus airbrakes)

There are also differences between different glider types in how much pitch changes with the airbrakes out. Some gliders pitch nose-down which helps give a good view of the reference point, some don't change pitch much. What matters of course is keeping the speed under control. The Junior pitches nose down a bit and you get a great view of where you are going. With me in it doesn't really chance speed (neigher does the K21) - my own glider speeds up, which IMHO is preferable to slowing down which some others do.

I'll be interested to see the final report, and five pages sounds pretty through to me though possibly it doesn't reach any firm conclusions.

[jgs43]

Interesting to read this thread.

It reminds me of a problem that a fair number of candidates had when attending BGA Instructor courses. Most had been trained on ASK21s while the BGA used Puchacz's in the course. The candidates generally had problems in maintaining airspeed when opening the airbrakes on approach on their first flight on type.

WHY?

Suggest that you try out this exercise next time that you fly a glider but do make sure that it is done at a safe height.

"First trim the glider to aproach speed then" -

"Take your hand off the stick then open the airbrakes. After the glider has stabilised close the airbrakes again."

Gliders with top surface airbrakes/spoilers will inevitable pitch nose down and initially increase airspeed. Closing the brakes has the opposite effect.

Gliders with top and bottom airbrakes/double paddles will tend to pitch nose up with a marked decrease in airspeed with the opposite occuring on closing the brakes.

WHAT DOES THIS MEAN?

Pilots trained in gliders with top surface airbrakes, like the ASK21, will automatically apply back pressure to the stick to prevent the nose down pitch and speed increase.
This becomes ingrained as a habit.
When they first fly a glider with double paddle brakes this habit catches them out as the glider pitches nose up on opening the brakes and demands a marked forward movement of the stick to both prevent the nose up pitch and also to maintain the airspeed.

The opposite, naturally, is also applicable to pilots trained on double paddle airbraked gliders converting to gliders with top surface only/spoilers aircraft.

They will tend to move the stick forward as they open the airbrakes unless they have been prebriefed on this difference.

For similar reasons changes in airbrake setting while rotating into the flare should also be avoided.

[cats_five]

<snip>
Gliders with top surface airbrakes/spoilers will inevitable pitch nose down and initially increase airspeed. Closing the brakes has the opposite effect.

Gliders with top and bottom airbrakes/double paddles will tend to pitch nose up with a marked decrease in airspeed with the opposite occuring on closing the brakes.
<snip>

Does CoG affect how much this happens in some gliders?

[jgs43]

Since the effect is dependant upon a number of factors such as aircraft design, movement of vectors , etc then, yes, the Cof G position may well play a part in determining the degree of pitch observed.

[mary meagher]

There may be two problems highlighted by this fatal accident in a Junior.

First, flying an approach with "airbrakes cracked open" is NOT A GOOD IDEA.
Perhaps the American recommendation of making sure you have the right handle by briefly flexing the brakes (excuse me, spoilers!) on downwind leg
is okay, though not practiced in the UK.

Then the pilot should set up a correct circuit. In US and Canada, very often a square circuit is required because the field is shared with power traffic.
In the UK we teach the "diagonal leg" which cuts off the corner and is much safer because you have the landing area in view and can reach it any time.

The final turn should be NO LOWER THAN 300 feet. And the correct position for the wind conditions. The airbrake (spoiler) should ideally be set at half open or a bit more if overshooting. If you felt it appropriate to only have the airbrake "cracked open" they shouldn't be open at all!

As a beginner, I used to have to reset the airbrakes on approach quite a lot. Sort of rowing. But never never just cracked open; if undershooting the brakes must be closed completely, and when re-established on the correct descent path, reopened to halfway again. Messing about at 50 feet or lower is asking for trouble.

Of course it is a good idea to test the effect of opening the brake at altitude. The exposition of pilots training to instruct being surprised by the opposite effect of single or double-paddle brakes is worth reading again!

THE SECOND PROBLEM is the Short Pilot. I, being female, am a relatively short pilot, and must have a non-compressible cushion behind me to reach the controls (this is made of newspaper with cloth cover, and you can stand on it and it won't squash at all). This means that in some gliders, it is very difficult to deploy the airbrakes. The short pilot should spend time without hassles finding out just how difficult deploying the airbrake is going to be, while safely on the ground. If not happy, don't fly that glider!

I really do like the Junior, they let me go rock polishing at Talgarth in the Junior, so for this short person, this particular Junior works just fine. And having very effective airbrakes is a great comfort when landing on that challenging site.

So in conclusion, though the Junior is shall we say, somewhat agricultural in finish, it is a worthy machine for an early solo pilot, properly trained, properly briefed, and properly fitting into the glider. The performance won't win any trophies, but you can get round your first 100 k on a decent day in a Junior.

[gpn01]

WHAT DOES THIS MEAN?

Pilots trained in gliders with top surface airbrakes, like the ASK21, will automatically apply back pressure to the stick to prevent the nose down pitch and speed increase.
This becomes ingrained as a habit.
When they first fly a glider with double paddle brakes this habit catches them out as the glider pitches nose up on opening the brakes and demands a marked forward movement of the stick to both prevent the nose up pitch and also to maintain the airspeed.

The opposite, naturally, is also applicable to pilots trained on double paddle airbraked gliders converting to gliders with top surface only/spoilers aircraft.


I keep my briefing on type conversion simple......"when you open the airbrakes you may find that it causes a pitch change that you need to counteract with the stick. It might be up, it might be down or even nothing at all. See what happens, and deal with it accordingly".

I find this is highly effective as it wakes them up to the possibility of a pitch change but it doesn't preload them with a default response.

[cats_five]

I witnessed this accident in August 2007. The Canada Transportation Safety board is about to release their report and I have posted my own observations and analysis at SoaringCanada.riq.ca :: View topic - August 2007 Junior Fatal Accident (http://soaringcanada.riq.ca/viewtopic.php?p=17635#17635)

From that URL:
Many of us have been waiting for the TSB report on this accident. Since TSB policy requires simultaneous availability of reports in both official languages and the French translation has just been done, report A07O0233 should be released and posted on the TSB website by March 12. It is available on request from TSB, http://www.tsb.gc.ca/eng/contactez-contact/index.asp (http://www.tsb.gc.ca/eng/contactez-contact/index.asp) . If you are at all familiar with TSB's major accident reports, you will find that this one is quite abbreviated, just five pages, and instead of findings of cause, offers guesses.

No sign of it yet that I can see.

[RatherBeFlying]

While I am subscribed to notifications of TSB report availability, I did not receive any for this accident; however I just had a look and see it is now available at:

Transportation Safety Board of Canada - AVIATION REPORTS - 2007 - A07O0233 (http://www.tsb.gc.ca/eng/rapports-reports/aviation/2007/a07o0233/a07o0233.asp)

PS. Yes, I know it's a SZD-51, but I can't change the title.