DG-1000 undercarriage collapses and inadvertent extensions ?

[Bernie[_2_]]

Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
has experienced multiple occurences of both inadvertent retraction and
extension of the undercarriage. Typically the undercarrriage has
dropped down whilst in flight, in various modes including straight and
level in smooth air.
We have also had a collapse on outlanding in a moderately field, and
very recently the gear collpased seconds after the glider had been
wheeled into the hangar; luckily no-one was injured but the wings hit
adjacent gliders.
The local DG agent has stated that he has not heard of any other
reports of DG-1000 U/C problems; however recently we heard another
Australian DG-1000 at Beverley in W.A. experienced a collapse (and
it's only a few months old).
It appears the overcentre mechanism requires very careful adjustment
to prevent the extension problem, however no apparent cause for the
retraction problem has been found. We have continually cautioned
pilots to make sure the U/C handle is pushed flush with the fuselage
wall after putting the gear down.
We are wondering if any other clubs or owners have experienced this
problem?

[Geoff Vincent]

Hi all,

This, together with the countless incidents involving DG-300 U/C
collapses isn't it about time the manufacturer got the engineering
design right?

Geoff Vincent

On 15 Apr 2007 00:55:02 -0700, "Bernie" >
wrote:

>Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
>has experienced multiple occurences of both inadvertent retraction and
>extension of the undercarriage. Typically the undercarrriage has
>dropped down whilst in flight, in various modes including straight and
>level in smooth air.
>We have also had a collapse on outlanding in a moderately field, and
>very recently the gear collpased seconds after the glider had been
>wheeled into the hangar; luckily no-one was injured but the wings hit
>adjacent gliders.
>The local DG agent has stated that he has not heard of any other
>reports of DG-1000 U/C problems; however recently we heard another
>Australian DG-1000 at Beverley in W.A. experienced a collapse (and
>it's only a few months old).
>It appears the overcentre mechanism requires very careful adjustment
>to prevent the extension problem, however no apparent cause for the
>retraction problem has been found. We have continually cautioned
>pilots to make sure the U/C handle is pushed flush with the fuselage
>wall after putting the gear down.
>We are wondering if any other clubs or owners have experienced this
>problem?

[Henk de Waard]

On 15 apr, 12:47, Geoff Vincent > wrote:
> Hi all,
>
> This, together with the countless incidents involving DG-300 U/C
> collapses isn't it about time the manufacturer got the engineering
> design right?
>
> Geoff Vincent
>
> On 15 Apr 2007 00:55:02 -0700, "Bernie" >
> wrote:
>
>
>
> >Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
> >has experienced multiple occurences of both inadvertent retraction and
> >extension of the undercarriage. Typically the undercarrriage has
> >dropped down whilst in flight, in various modes including straight and
> >level in smooth air.
> >We have also had a collapse on outlanding in a moderately field, and
> >very recently the gear collpased seconds after the glider had been
> >wheeled into the hangar; luckily no-one was injured but the wings hit
> >adjacent gliders.
> >The local DG agent has stated that he has not heard of any other
> >reports of DG-1000 U/C problems; however recently we heard another
> >Australian DG-1000 at Beverley in W.A. experienced a collapse (and
> >it's only a few months old).
> >It appears the overcentre mechanism requires very careful adjustment
> >to prevent the extension problem, however no apparent cause for the
> >retraction problem has been found. We have continually cautioned
> >pilots to make sure the U/C handle is pushed flush with the fuselage
> >wall after putting the gear down.
> >We are wondering if any other clubs or owners have experienced this
> >problem?- Tekst uit oorspronkelijk bericht niet weergeven -
>
> - Tekst uit oorspronkelijk bericht weergeven -

I had a gear collapse on a normal landing with a DG1000T march last
year. In July last year I saw a gear collapse on a normal landing with
a DG1000T in Sweden. So it happens more.

Henk

[Henk de Waard]

On 15 apr, 12:47, Geoff Vincent > wrote:
> Hi all,
>
> This, together with the countless incidents involving DG-300 U/C
> collapses isn't it about time the manufacturer got the engineering
> design right?
>
> Geoff Vincent
>
> On 15 Apr 2007 00:55:02 -0700, "Bernie" >
> wrote:
>
>
>
> >Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
> >has experienced multiple occurences of both inadvertent retraction and
> >extension of the undercarriage. Typically the undercarrriage has
> >dropped down whilst in flight, in various modes including straight and
> >level in smooth air.
> >We have also had a collapse on outlanding in a moderately field, and
> >very recently the gear collpased seconds after the glider had been
> >wheeled into the hangar; luckily no-one was injured but the wings hit
> >adjacent gliders.
> >The local DG agent has stated that he has not heard of any other
> >reports of DG-1000 U/C problems; however recently we heard another
> >Australian DG-1000 at Beverley in W.A. experienced a collapse (and
> >it's only a few months old).
> >It appears the overcentre mechanism requires very careful adjustment
> >to prevent the extension problem, however no apparent cause for the
> >retraction problem has been found. We have continually cautioned
> >pilots to make sure the U/C handle is pushed flush with the fuselage
> >wall after putting the gear down.
> >We are wondering if any other clubs or owners have experienced this
> >problem?- Tekst uit oorspronkelijk bericht niet weergeven -
>
> - Tekst uit oorspronkelijk bericht weergeven -

I had a gear collapse upon landing with a DG1000T March last year and
I witnessed a gear collapse with another DG1000T in Sweden last July.
Both were normal landings on grass and there was no damage to the
airplane.

Henk

[Mal[_3_]]

"Geoff Vincent" > wrote in message
...
> Hi all,
>
> This, together with the countless incidents involving DG-300 U/C
> collapses isn't it about time the manufacturer got the engineering
> design right?
>
> Geoff Vincent
>
> On 15 Apr 2007 00:55:02 -0700, "Bernie" >
> wrote:
>
>>Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
>>has experienced multiple occurences of both inadvertent retraction and
>>extension of the undercarriage. Typically the undercarrriage has
>>dropped down whilst in flight, in various modes including straight and
>>level in smooth air.
>>We have also had a collapse on outlanding in a moderately field, and
>>very recently the gear collpased seconds after the glider had been
>>wheeled into the hangar; luckily no-one was injured but the wings hit
>>adjacent gliders.
>>The local DG agent has stated that he has not heard of any other
>>reports of DG-1000 U/C problems; however recently we heard another
>>Australian DG-1000 at Beverley in W.A. experienced a collapse (and
>>it's only a few months old).
>>It appears the overcentre mechanism requires very careful adjustment
>>to prevent the extension problem, however no apparent cause for the
>>retraction problem has been found. We have continually cautioned
>>pilots to make sure the U/C handle is pushed flush with the fuselage
>>wall after putting the gear down.
>>We are wondering if any other clubs or owners have experienced this
>>problem?
>

Maybe I am just lucky NOT I have flown DGI more than 25 times and no
problems.

The DG 1000 just has to be locked in position like the DG 303 and any other
aircraft.

Then check it by pulling back hard against it in the locked position.

A smooth landing can also help a tail first drop on gives the U/C a good
thump.

I always make sure that I have three greens on three separate occasions in
the circuit and apply the same physical check to a glider U/C three times in
my circuit.

[Lars Peder Hansen]

My club in Denmark (www.bsk-billund.dk) operates DG-1000 serial #7. In the
first couple of years we had several gear collapses, both while landing and
while being towed back to takeoff by a tractor. Clearly, something was
wrong.

We then had the DG sent off to the Danish representative (www.dan-glide.dk),
and some modifications were made. Now it has been working perfetly for a
long time.
You may want to contact Mr. Morten Habekost of Dan-Glide
) I am quite sure that the DG factory was involved in
the solution, and that they are aware of this issue.

Happy Soaring,
Lars Peder

Replace numbers by post1.tele.dk to reply by e-mail




"Bernie" > wrote in message
ups.com...
> Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
> has experienced multiple occurences of both inadvertent retraction and
> extension of the undercarriage. Typically the undercarrriage has
> dropped down whilst in flight, in various modes including straight and
> level in smooth air.
> We have also had a collapse on outlanding in a moderately field, and
> very recently the gear collpased seconds after the glider had been
> wheeled into the hangar; luckily no-one was injured but the wings hit
> adjacent gliders.
> The local DG agent has stated that he has not heard of any other
> reports of DG-1000 U/C problems; however recently we heard another
> Australian DG-1000 at Beverley in W.A. experienced a collapse (and
> it's only a few months old).
> It appears the overcentre mechanism requires very careful adjustment
> to prevent the extension problem, however no apparent cause for the
> retraction problem has been found. We have continually cautioned
> pilots to make sure the U/C handle is pushed flush with the fuselage
> wall after putting the gear down.
> We are wondering if any other clubs or owners have experienced this
> problem?
>

[Philip Plane]

Bernie wrote:
> Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
> has experienced multiple occurences of both inadvertent retraction and
> extension of the undercarriage. Typically the undercarrriage has
> dropped down whilst in flight, in various modes including straight and
> level in smooth air.
...
> It appears the overcentre mechanism requires very careful adjustment
> to prevent the extension problem, however no apparent cause for the
> retraction problem has been found. We have continually cautioned
> pilots to make sure the U/C handle is pushed flush with the fuselage
> wall after putting the gear down.
> We are wondering if any other clubs or owners have experienced this
> problem?

There is a mod to increase the overcenter. My DG doesn't have it, mostly
because we haven't had a problem.

I've done 335 takeoffs and landings in my DG1000. On a variety of surfaces,
but mostly on Omarama which has a hard, rough surface. Never had a problem.

I have observed the other pilot failing to lock the gear positively up or
down a number of times though. I always give the gear a personal check after
the front seater has lowered it.

There was the time an airline pilot was adjusting the trim while the
glider was on the grid and pulled the wrong lever. The airline pilot
wasn't damaged. Now I know that you can retract the gear on the ground.

--
Philip Plane _____
|
---------------( )---------------
Glider pilots have no visible means of support

[Derek Copeland]

Our club in the UK has two DG1000s with the two wheel
tail dragger configuration. We have had numerous undercarriage
collapses on landing, but as far as I know no unwanted
extentions in flight.

The problem seems to be that a great deal of force
is required to get the gear over-centre and that the
lever in the front cockpit has a very long throw. People
with short arms, or who are not very strong have a
real problem getting the wheel to lock down. I personally
find the U/C reasonably OK to operate from the rear
cockpit, but very difficult from the front. And yes
I have had the U/C retract on landing, which was very
embarassing.

The whole thing seems to be very poor from an ergonomic
point of view.

Derek Copeland



At 20:36 15 April 2007, Philip Plane wrote:
>Bernie wrote:
>> Our DG-1000 at Southern Cross Gliding Club (Camden,
>>NSW, Australia)
>> has experienced multiple occurences of both inadvertent
>>retraction and
>> extension of the undercarriage. Typically the undercarrriage
>>has
>> dropped down whilst in flight, in various modes including
>>straight and
>> level in smooth air.
> ...
>> It appears the overcentre mechanism requires very
>>careful adjustment
>> to prevent the extension problem, however no apparent
>>cause for the
>> retraction problem has been found. We have continually
>>cautioned
>> pilots to make sure the U/C handle is pushed flush
>>with the fuselage
>> wall after putting the gear down.
>> We are wondering if any other clubs or owners have
>>experienced this
>> problem?
>
>There is a mod to increase the overcenter. My DG doesn't
>have it, mostly
>because we haven't had a problem.
>
>I've done 335 takeoffs and landings in my DG1000. On
>a variety of surfaces,
>but mostly on Omarama which has a hard, rough surface.
>Never had a problem.
>
>I have observed the other pilot failing to lock the
>gear positively up or
>down a number of times though. I always give the gear
>a personal check after
>the front seater has lowered it.
>
>There was the time an airline pilot was adjusting the
>trim while the
>glider was on the grid and pulled the wrong lever.
>The airline pilot
>wasn't damaged. Now I know that you can retract the
>gear on the ground.
>
>--
>Philip Plane _____
> |
> ---------------( )---------------
>Glider pilots have no visible means of support
>

[Jeremy Zawodny]

Derek Copeland wrote:
> Our club in the UK has two DG1000s with the two wheel
> tail dragger configuration. We have had numerous undercarriage
> collapses on landing, but as far as I know no unwanted
> extentions in flight.

Our club has #23 and has put *a lot* of hours and landings on it in the
last few years. No retract problems so far on landing. We have the 3
wheel variety (nose, main, and tail) but I'm not sure if that makes much
difference.

Jeremy

[Stefan]

Jeremy Zawodny schrieb:
> Derek Copeland wrote:
>> Our club in the UK has two DG1000s with the two wheel
>> tail dragger configuration. We have had numerous undercarriage
>> collapses on landing, but as far as I know no unwanted
>> extentions in flight.
>
> Our club has #23 and has put *a lot* of hours and landings on it in the
> last few years. No retract problems so far on landing.

My completely uninformed guess is that those unexpectedly retracted
gears were just not locked. I *almost* landed with an extended but
unlocked gear myself, but recognized the situation just in time. It
takes a lot of force to correctly lock the gear. Start the process early
and always visually double check the handle position.

[KP]

On my ASW-27 the gear warning will come on if the gear is not all the
way in the locked position and the spoilers are activated.
I installed an intermitting sound alert that beep and a LED next to
the airspeed indicator that flashes. Now all I need now is a 25k volt
discharge to my butt and then maybe I will not land gear up . ;-)

Ken (KP)

[Shawn[_3_]]

Derek Copeland wrote:
> Our club in the UK has two DG1000s with the two wheel
> tail dragger configuration. We have had numerous undercarriage
> collapses on landing, but as far as I know no unwanted
> extentions in flight.
>
> The problem seems to be that a great deal of force
> is required to get the gear over-centre and that the
> lever in the front cockpit has a very long throw. People
> with short arms, or who are not very strong have a
> real problem getting the wheel to lock down. I personally
> find the U/C reasonably OK to operate from the rear
> cockpit, but very difficult from the front. And yes
> I have had the U/C retract on landing, which was very
> embarassing.
>
> The whole thing seems to be very poor from an ergonomic
> point of view.

Anyone seen this problem in the 505?

Thanks,
Shawn

[Andreas Maurer]

On Wed, 18 Apr 2007 20:41:28 -0600, Shawn >
wrote:

>Anyone seen this problem in the 505?

Nope. No problem at all in the 505.

Bye
Andreas

[Karl Striedieck]

While flying a 1000 at the Seniors a couple years ago I heard the gearing
warning horn on short final, checked that the gear handle was down, landed,
rolled 2 meters and the gear collapsed. I assumed I hadn't "seated" the
handle right and flew the next day without further investigation. The gear
collapsed again.

Looking into the landing gear operation revealed the problem and it is not
an "over center" condition. The down lock for the 1000 gear is a steel plate
under the left plastic trim panel that hides the gear push rods running
between the two cockpits, just below the canopy rail. There is a tab on the
push rod that is supposed to rotate behind a steel plate far enough to
prevent the push rod (and handles) from moving out of the down position.
This steel plate was incorrectly positioned so that the gear was barely safe
in the down position, but with the slightest rotation inboard or vibration
on landing it became unlocked.

It was a very simple matter of repositioning the plate to correct the
problem.

Karl Striedieck



"Andreas Maurer" > wrote in message
...
> On Wed, 18 Apr 2007 20:41:28 -0600, Shawn >
> wrote:
>
>>Anyone seen this problem in the 505?
>
> Nope. No problem at all in the 505.
>
> Bye
> Andreas

[[email protected]]

On Apr 15, 3:47 am, Geoff Vincent >
wrote:
> Hi all,
>
> This, together with the countless incidents involving DG-300 U/C
> collapses isn't it about time the manufacturer got the engineering
> design right?
>
> Geoff Vincent

I'm not sure past issues with the 30x and any current issues with the
1000 are directly related, but what amazes me is the large percentage
of DG-30x owners I've spoken with who do not know of the undercarriage
handle TN 359/22. I've even spoken with a DG-303 owner who had a gear
collapse, had the gelcoat repaired and was back flying but was still
not aware of the TN (kind of makes me think he should find another
repair shop as well). The original rubber pressure block and metal
plate with a little metal knub that was supposed to hold the handle
locked was really a pathetic design and likely to come out of
adjustment, the TN adds a coil spring that keeps the handle more
firmly rotated in place. A few hundred dollars well spent. The DG-30x
(and other gliders) also need to have their U/C overcenter locking gas
strut inspected periodically.

Darryl

[Derek Copeland]

Jeremy's uninformed guess is perfectly correct. The
problem is that to get the U/C properly overcentre
requires a really long and hard shove forward, and
there is only about a one mm difference in the position
of the lever between the U/C being locked down and
not locked down. The more recent of our two DG1000s
has a small detent in the sidewall to indicate that
the gear is properly locked down, but is still far
too heavy and awkward to operate, especially in the
front cockpit. On a recent flight it took me 10 attempts
to get the lever into the detent, and I am not exactly
small or weak.

Derek Copeland

At 19:36 18 April 2007, Stefan wrote:
>Jeremy Zawodny schrieb:
>> Derek Copeland wrote:
>>> Our club in the UK has two DG1000s with the two wheel
>>> tail dragger configuration. We have had numerous undercarriage
>>> collapses on landing, but as far as I know no unwanted
>>> extentions in flight.
>>
>> Our club has #23 and has put *a lot* of hours and
>>landings on it in the
>> last few years. No retract problems so far on landing.
>>
>
>My completely uninformed guess is that those unexpectedly
>retracted
>gears were just not locked. I *almost* landed with
>an extended but
>unlocked gear myself, but recognized the situation
>just in time. It
>takes a lot of force to correctly lock the gear. Start
>the process early
>and always visually double check the handle position.
>

[Jeremy Zawodny]

Just for the record, that was Stefan, not me. :-)

As far as I know, I've always had the gear locked.

Jeremy [knocking on wood...]

Derek Copeland wrote:
> Jeremy's uninformed guess is perfectly correct. The
> problem is that to get the U/C properly overcentre
> requires a really long and hard shove forward, and
> there is only about a one mm difference in the position
> of the lever between the U/C being locked down and
> not locked down. The more recent of our two DG1000s
> has a small detent in the sidewall to indicate that
> the gear is properly locked down, but is still far
> too heavy and awkward to operate, especially in the
> front cockpit. On a recent flight it took me 10 attempts
> to get the lever into the detent, and I am not exactly
> small or weak.
>
> Derek Copeland
>
> At 19:36 18 April 2007, Stefan wrote:
>> Jeremy Zawodny schrieb:
>>> Derek Copeland wrote:
>>>> Our club in the UK has two DG1000s with the two wheel
>>>> tail dragger configuration. We have had numerous undercarriage
>>>> collapses on landing, but as far as I know no unwanted
>>>> extentions in flight.
>>> Our club has #23 and has put *a lot* of hours and
>>> landings on it in the
>>> last few years. No retract problems so far on landing.
>>>
>> My completely uninformed guess is that those unexpectedly
>> retracted
>> gears were just not locked. I *almost* landed with
>> an extended but
>> unlocked gear myself, but recognized the situation
>> just in time. It
>> takes a lot of force to correctly lock the gear. Start
>> the process early
>> and always visually double check the handle position.
>>
>
>
>

[Jim Hultman]

Happened to me in a 505, & I'm a long-armed gear slammer.
Jim
"Shawn" > wrote in message
. ..
> Derek Copeland wrote:
> > Our club in the UK has two DG1000s with the two wheel
> > tail dragger configuration. We have had numerous undercarriage
> > collapses on landing, but as far as I know no unwanted
> > extentions in flight.
> >
> > The problem seems to be that a great deal of force
> > is required to get the gear over-centre and that the
> > lever in the front cockpit has a very long throw. People
> > with short arms, or who are not very strong have a
> > real problem getting the wheel to lock down. I personally
> > find the U/C reasonably OK to operate from the rear
> > cockpit, but very difficult from the front. And yes
> > I have had the U/C retract on landing, which was very
> > embarassing.
> >
> > The whole thing seems to be very poor from an ergonomic
> > point of view.
>
> Anyone seen this problem in the 505?
>
> Thanks,
> Shawn

[Derek Copeland]

Between two club owned and one privately owned DG1000
gliders at our site, we have so far averaged about
1 undercarriage retraction on landing approximately
every 200 flights. Probably all of these were failures
to lock the U/C down properly, for the reasons stated
previously. The only good news is that a reasonable
landing on smooth grass doesn't seem to cause much
damage beyond ripping off the odd undercarriage door.


Getting a big group of people together to lift a stranded
DG1000 off the ground after an U/C collapse, so that
the wheel can be lowered, has almost become a routine
occurrence at our club!

Sometimes the U/C locks down quite easily, but on other
occasions it’s like pushing against a brick wall! I
thought that it might be related to airspeed, as you
have to push the wheel forward into the slipstream,
but on the last occasion I had difficulties slowing
down to the stall made no difference.

BTW I flew the DG1000 prototype demonstrator on a number
of occasions and didn't find any problems operating
the undercarriage, so it is something that has crept
in on production models. Neither have I had any problems
operating DG500 (3-wheeler) or DG300 undercarriages.

Derek Copeland

At 04:54 22 April 2007, Jim Hultman wrote:
>Happened to me in a 505, & I'm a long-armed gear slammer.
>Jim
>'Shawn' wrote in message
. ..
>> Derek Copeland wrote:
>> > Our club in the UK has two DG1000s with the two wheel
>> > tail dragger configuration. We have had numerous
>>>undercarriage
>> > collapses on landing, but as far as I know no unwanted
>> > extentions in flight.
>> >
>> > The problem seems to be that a great deal of force
>> > is required to get the gear over-centre and that
>>>the
>> > lever in the front cockpit has a very long throw.
>>>People
>> > with short arms, or who are not very strong have
>>>a
>> > real problem getting the wheel to lock down. I personally
>> > find the U/C reasonably OK to operate from the rear
>> > cockpit, but very difficult from the front. And yes
>> > I have had the U/C retract on landing, which was
>>>very
>> > embarassing.
>> >
>> > The whole thing seems to be very poor from an ergonomic
>> > point of view.
>>
>> Anyone seen this problem in the 505?
>>
>> Thanks,
>> Shawn
>
>
>

[Jack]

Derek Copeland wrote:

> Getting a big group of people together to lift a stranded
> DG1000 off the ground after an U/C collapse, so that
> the wheel can be lowered, has almost become a routine
> occurrence at our club!


How do you go about this, in detail?



> Sometimes the U/C locks down quite easily, but on other
> occasions it’s like pushing against a brick wall! I
> thought that it might be related to airspeed, as you
> have to push the wheel forward into the slipstream,
> but on the last occasion I had difficulties slowing
> down to the stall made no difference.


Have you tried under various g-load conditions?



Jack

[Derek Copeland]

At 01:18 24 April 2007, Jack wrote:
>Derek Copeland wrote:
>
>> Getting a big group of people together to lift a stranded
>> DG1000 off the ground after an U/C collapse, so that
>> the wheel can be lowered, has almost become a routine
>> occurrence at our club!
>
>How do you go about this, in detail?
>
You ask them very politely! You get some of them to
squat under the mainspar and stand up at the appropriate
moment while others lift on the leading edges of the
wings. One person is required to operate the U/C lever.
The turbo version is significantly heavier to lift.

>
>> Sometimes the U/C locks down quite easily, but on
>>other
>> occasions it’s like pushing against a brick wall!
>>I
>> thought that it might be related to airspeed, as you
>> have to push the wheel forward into the slipstream,
>> but on the last occasion I had difficulties slowing
>> down to the stall made no difference.
>
>
>Have you tried under various g-load conditions?
>
Yes!
>
Derek C

[Bob Whelan]

> At 01:18 24 April 2007, Jack wrote:
>
>>Derek Copeland wrote:
>>
>>
>>>Getting a big group of people together to lift a stranded
>>>DG1000 off the ground after an U/C collapse, so that
>>>the wheel can be lowered, has almost become a routine
>>>occurrence at our club!
>>
>>How do you go about this, in detail?
>>
>
> You ask them very politely! You get some of them to
> squat under the mainspar and stand up at the appropriate
> moment while others lift on the leading edges of the
> wings. One person is required to operate the U/C lever.
> The turbo version is significantly heavier to lift.
>
An Archimedean approach requiring fewer, weaker people might be to
simply 'walk up' the fuselage from below, levering about the ship's
changing nose pivot point, until the gear can be lowered. Works with 15
meter ships. Protect the nose, of course. Not an original idea. YMMV.

Regards,
Bob Whelan

[Derek Copeland]

We have been told by our CFI not to do it the way Bob
suggests, although we have used this technique on other
gliders. I guess the reason is that the two wheeler
type main wheel sticks out an awfully long way, so
you may not be able to lift the tail high enough. Alternatively
it may risk damaging the nose or the tailboom.

If the undercarriage had been properly designed from
an engineering and ergonomic point of view, this procedure
wouldn't be necessary anyway! BTW the glider comes
with a gear up warning as standard, but quite a few
people (including me) have failed to lock the undercarriage
down properly, even with the warning going off. I thought
that a microswitch must have failed because the U/C
sounded as if it had locked down and the lever appeared
to be fully forward.

Derek Copeland

At 04:24 28 April 2007, Bob Whelan wrote:
>> At 01:18 24 April 2007, Jack wrote:
>>
>>>Derek Copeland wrote:
>>>
>>>
>>>>Getting a big group of people together to lift a stranded
>>>>DG1000 off the ground after an U/C collapse, so that
>>>>the wheel can be lowered, has almost become a routine
>>>>occurrence at our club!
>>>
>>>How do you go about this, in detail?
>>>
>>
>> You ask them very politely! You get some of them to
>> squat under the mainspar and stand up at the appropriate
>> moment while others lift on the leading edges of the
>> wings. One person is required to operate the U/C lever.
>> The turbo version is significantly heavier to lift.
>>
>An Archimedean approach requiring fewer, weaker people
>might be to
>simply 'walk up' the fuselage from below, levering
>about the ship's
>changing nose pivot point, until the gear can be lowered.
> Works with 15
>meter ships. Protect the nose, of course. Not an
>original idea. YMMV.
>
>Regards,
>Bob Whelan
>

[Derek Copeland]

I have carried out a few more investigations on the
problem of locking the undercarriage down from the
front cockpit.

Basically if you can't get the palm of your left hand
at least level with the back of the undercarriage lever
when strapped in on the ground with the wheel down,
you probably won't be able to lock the U/C down in
flight. Pad yourself forward with firm cushions until
you can. The cushions have to be firm as you need something
to push against.

To put the wheel down twist the lever out and down,
and take a long hard run at it. If you keep the lever
too close to the cockpit wall, you risk jamming your
fingers against a bulkhead, just like I managed to
do the other week. The bruising has just about subsided!

If you think that the U/C has locked down properly,
then push the lever against the side wall, check that
it fits into the detent if fitted, or that the lever
is fully forward, and then briefly open the airbrakes
to see if the warning goes off. If it doesn't you should
be OK.

BTW people with long arms find it difficult to lock
the wheel up, as their elbows hit the seat back first.
I still think that the ergonomics of this system are
appalling.

Derek Copeland


At 09:12 28 April 2007, Derek Copeland wrote:
>We have been told by our CFI not to do it the way Bob
>suggests, although we have used this technique on other
>gliders. I guess the reason is that the two wheeler
>type main wheel sticks out an awfully long way, so
>you may not be able to lift the tail high enough. Alternatively
>it may risk damaging the nose or the tailboom.
>
>If the undercarriage had been properly designed from
>an engineering and ergonomic point of view, this procedure
>wouldn't be necessary anyway! BTW the glider comes
>with a gear up warning as standard, but quite a few
>people (including me) have failed to lock the undercarriage
>down properly, even with the warning going off. I thought
>that a microswitch must have failed because the U/C
>sounded as if it had locked down and the lever appeared
>to be fully forward.
>
>Derek Copeland
>

[[email protected]]

On Apr 15, 12:55 am, "Bernie" > wrote:
> Our DG-1000 at Southern Cross Gliding Club (Camden, NSW, Australia)
> has experienced multiple occurences of both inadvertent retraction and
> extension of the undercarriage. Typically the undercarrriage has
> dropped down whilst in flight, in various modes including straight and
> level in smooth air.
> We have also had a collapse on outlanding in a moderately field, and
> very recently the gear collpased seconds after the glider had been
> wheeled into the hangar; luckily no-one was injured but the wings hit
> adjacent gliders.
> The local DG agent has stated that he has not heard of any other
> reports of DG-1000 U/C problems; however recently we heard another
> Australian DG-1000 at Beverley in W.A. experienced a collapse (and
> it's only a few months old).
> It appears the overcentre mechanism requires very careful adjustment
> to prevent the extension problem, however no apparent cause for the
> retraction problem has been found. We have continually cautioned
> pilots to make sure the U/C handle is pushed flush with the fuselage
> wall after putting the gear down.
> We are wondering if any other clubs or owners have experienced this
> problem?

I also had an uncommanded gear collapse of my DG-400 (did over $3,000
in damage). The repair shop could not find any problem with the gear
mechanism; the gas strut was ok and the detent mechanism, such as it
is, was properly adjusted. I solved the problem by installing a gate
deadbolt procured from a local hardware store. Cost: $3. A friend of
my had a similar mishap with his DG-400.

I posted a similar question on RAS over 9 years ago. The responses
fell into two categories:
1. It has never happened to me and it won't happen to you if the
glider is properly maintained.
2. It has happened to me X times.

I have not seen the mechanism on the DG-1000, but it sounds similar.
DG has made various design modifications to eliminate the problem, but
it sounds like they are still searching for the right receipe.

I recommend installing some sort of positive mechanical lock (with the
usual inspection sign-offs, paperwork, etc.) that can't possibly fail.

Tom