Water ballast bag replacement surprise...

Today I pulled out the RIGHT-side water ballast bag from the wing of
my DG-300 (s/n 3E1). Before I began this I noted 3 strings sticking
out (two white, one yellow) and was prepared to attach a line to the
one that began to disappear into the wing as I removed the bag (this
string would be attached to the end of the replacement bag and used to
pull it back in).

Surprise! None of the strings was attached to the bag! The bag came
out without any strings tied to the end. The three strings that were
there before I removed the bag remained in place, presumably anchored
where they would normally be to secure the bags. (The LEFT-side had
the normal string arrangement, so I should be able to insert the left-
side replacement bag easily.)

How am I going to install the right-side replacement bag?

Because I saw no string (i.e., broken remenants) attached to the end
of the old bag, it seems that the old bag had somehow been inserted
without being pulled in with the normal string arrangement.
Possible? Also, the old bag seemed to stay in place without being
anchored (DG's manual say you should periodically check the string
tension to make sure the bags are held in place).

Any suggestions about how to get the replacement bag *in place* and
*secured* will be gratefully accepted!

Thanks,

Eric

On Jun 13, 9:06*pm, Itsaplane wrote:
Today I pulled out the RIGHT-side water ballast bag from the wing of
my DG-300 (s/n 3E1). *Before I began this I noted 3 strings sticking
out (two white, one yellow) and was prepared to attach a line to the
one that began to disappear into the wing as I removed the bag (this
string would be attached to the end of the replacement bag and used to
pull it back in).

Surprise! *None of the strings was attached to the bag! *The bag came
out without any strings tied to the end. *The three strings that were
there before I removed the bag remained in place, presumably anchored
where they would normally be to secure the bags. *(The LEFT-side had
the normal string arrangement, so I should be able to insert the left-
side replacement bag easily.)

How am I going to install the right-side replacement bag?

Because I saw no string (i.e., broken remenants) attached to the end
of the old bag, it seems that the old bag had somehow been inserted
without being pulled in with the normal string arrangement.
Possible? *Also, the old bag seemed to stay in place without being
anchored (DG's manual say you should periodically check the string
tension to make sure the bags are held in place).

Any suggestions about how to get the replacement bag *in place* and
*secured* will be gratefully accepted!

Thanks,

Eric

I fly a ASW-20B - the strings are long gone. Have been using a half
inch pvc pipe that is the length of the bag and secured to the
outboard tip of the bag. roll the bag around the pipe - feed it in
the wing - and leave it there.. Works great in my bird. Not familiar
with the DG

Cheers,
mp

On Jun 13, 7:06*pm, Itsaplane wrote:
Today I pulled out the RIGHT-side water ballast bag from the wing of
my DG-300 (s/n 3E1). *Before I began this I noted 3 strings sticking
out (two white, one yellow) and was prepared to attach a line to the
one that began to disappear into the wing as I removed the bag (this
string would be attached to the end of the replacement bag and used to
pull it back in).

Surprise! *None of the strings was attached to the bag! *The bag came
out without any strings tied to the end. *The three strings that were
there before I removed the bag remained in place, presumably anchored
where they would normally be to secure the bags. *(The LEFT-side had
the normal string arrangement, so I should be able to insert the left-
side replacement bag easily.)

How am I going to install the right-side replacement bag?

Because I saw no string (i.e., broken remenants) attached to the end
of the old bag, it seems that the old bag had somehow been inserted
without being pulled in with the normal string arrangement.
Possible? *Also, the old bag seemed to stay in place without being
anchored (DG's manual say you should periodically check the string
tension to make sure the bags are held in place).

Any suggestions about how to get the replacement bag *in place* and
*secured* will be gratefully accepted!

Thanks,

Eric

The fact that you saw three strings leads me to believe you a type of
setup where there is a continuous loop of cord that threads through a
pully-like mechanism at the tip of the wing. This is then used like a
clotheline to pull the end of the bag into the wing. The end of the
bag is tied with a short string to the continuous loop and hauled into
the wing. One Pegasus I flew had this arrangement.

I use the 1/2" PVC-pipe-inserted-into-the-bag method to push the bag
into the wing (end of pipe padded with duct tape; two lengths of pipe
joined with a wood dowel for easy storage in trailer). Never have been
able to pull the current bags all the way out into the wing with just
the string. Years ago, I watched the dealer install a set of double-
layer [loaner] factory bags in my new glider by propping the spar up
on a sawhorse, putting the tip on the ground, and yanking on the
string hard as he shoved handfuls of bag into the wing while I bounced
the wing. Had some left over so he just pushed that in, too. Scary.

I remove the pipe after installing the bag. In the old days (1970s),
not all gliders had strings. The bags mostly worked fine without them.
"Mostly" means that once in a while the bag would get twisted and trap
a lot of water outboard. Bad. I think the strings help to prevent
that. If you've got three strings in the wing, I suspect at least two
of them are connected.

It also depends on what your bags are made of. The original Smiley
bags in the US were relatively lightweight, smooth (yellow) material.
It was easy to slide them out into the wing. The later Smiley bags
were heavy, rubberized (black) fabric. Tough. But heavy. Much more
difficult to slide out. My LS-3 had smooth, lightweight material and
they were easy to pull out into the wing with the string.

Sell the glider and buy one with hard tanks. Oh, but there are
potential problems with those, too. Let's just ban water ballast
altogether. The gliders fly so much better on strong days but it's
a real pain to deal with on the ground. I'm flying the Sports Class
Nats in the US this year so don't have to worry about it.

Chip Bearden
ASW 24 "JB"
USA

On Jun 15, 10:28*am, Chip Bearden wrote:
I use the 1/2" PVC-pipe-inserted-into-the-bag method to push the bag
into the wing (end of pipe padded with duct tape; two lengths of pipe
joined with a wood dowel for easy storage in trailer). Never have been
able to pull the current bags all the way out into the wing with just
the string. Years ago, I watched the dealer install a set of double-
layer [loaner] factory bags in my new glider by propping the spar up
on a sawhorse, putting the tip on the ground, and yanking on the
string hard as he shoved handfuls of bag into the wing while I bounced
the wing. Had some left over so he just pushed that in, too. Scary.

I remove the pipe after installing the bag. In the old days (1970s),
not all gliders had strings. The bags mostly worked fine without them.
"Mostly" means that once in a while the bag would get twisted and trap
a lot of water outboard. Bad. I think the strings help to prevent
that. If you've got three strings in the wing, I suspect at least two
of them are connected.

It also depends on what your bags are made of. The original Smiley
bags in the US were relatively lightweight, smooth (yellow) material.
It was easy to slide them out into the wing. The later Smiley bags
were heavy, rubberized (black) fabric. Tough. But heavy. Much more
difficult to slide out. My LS-3 had smooth, lightweight material and
they were easy to pull out into the wing with the string.

Sell the glider and buy one with hard tanks. Oh, but there are
potential problems with those, too. Let's just ban water ballast
altogether. The gliders fly so much better on strong days but it's
a real pain to deal with on the ground. I'm flying the Sports Class
Nats in the US this year so don't have to worry about it.

Chip Bearden
ASW 24 "JB"
USA

Just a thought - I've never actually replaced a water bag.

There are long, stiff, skinny rods of plastic or wire available. (10
meter 4mm diameter rods of various plastics are sold at my local
supplier.) If one of these were inserted through the hole in the wing
tip until it emerged at the root, you could tape a string on this and
pull it back through the wing. You could then tie the string to the
end of the bag and pull it into the wing.

If you think about it, the glider manufacturer had to do something
like this since the string probably wasn't inside the wing when the
skins were joined.

Nuts?

On Jun 15, 9:56*am, bildan wrote:
On Jun 15, 10:28*am, Chip Bearden wrote:



I use the 1/2" PVC-pipe-inserted-into-the-bag method to push the bag
into the wing (end of pipe padded with duct tape; two lengths of pipe
joined with a wood dowel for easy storage in trailer). Never have been
able to pull the current bags all the way out into the wing with just
the string. Years ago, I watched the dealer install a set of double-
layer [loaner] factory bags in my new glider by propping the spar up
on a sawhorse, putting the tip on the ground, and yanking on the
string hard as he shoved handfuls of bag into the wing while I bounced
the wing. Had some left over so he just pushed that in, too. Scary.

I remove the pipe after installing the bag. In the old days (1970s),
not all gliders had strings. The bags mostly worked fine without them.
"Mostly" means that once in a while the bag would get twisted and trap
a lot of water outboard. Bad. I think the strings help to prevent
that. If you've got three strings in the wing, I suspect at least two
of them are connected.

It also depends on what your bags are made of. The original Smiley
bags in the US were relatively lightweight, smooth (yellow) material.
It was easy to slide them out into the wing. The later Smiley bags
were heavy, rubberized (black) fabric. Tough. But heavy. Much more
difficult to slide out. My LS-3 had smooth, lightweight material and
they were easy to pull out into the wing with the string.

Sell the glider and buy one with hard tanks. Oh, but there are
potential problems with those, too. Let's just ban water ballast
altogether. The gliders fly so much better on strong days but it's
a real pain to deal with on the ground. I'm flying the Sports Class
Nats in the US this year so don't have to worry about it.

Chip Bearden
ASW 24 "JB"
USA

Just a thought - I've never actually replaced a water bag.

There are long, stiff, skinny rods of plastic or wire *available. *(10
meter 4mm diameter rods of various plastics are sold at my local
supplier.) If one of these were inserted through the hole in the wing
tip until it emerged at the root, you could tape a string on this and
pull it back through the wing. *You could then tie the string to the
end of the bag and pull it into the wing.

If you think about it, the glider manufacturer had to do something
like this since the string probably wasn't inside the wing when the
skins were joined.

Nuts?

I suspect to make it easy the strings are installed with the pulleys
during manufacture.

Darryl

On Jun 15, 9:28*am, Chip Bearden wrote:
I use the 1/2" PVC-pipe-inserted-into-the-bag method to push the bag
into the wing (end of pipe padded with duct tape; two lengths of pipe
joined with a wood dowel for easy storage in trailer).

I had an ASW 19 for 15 years. Like Chip I pushed the bags into the
wings with PVC pipe. My bags held far more water than allowed by max
gross weight. The tip ends of the bags were folded back over the main
body of the bag to reduce length and capacity and the overlapping
parts were tied together in about 4 places. The PVC pipe end was
capped with a T fitting that pushed against the fold line. The pipe
was removed after bag insertion and was kept in the trailer in case it
was needed at an away contest.

I had a string on each bags that secured them to the outer end of the
airbrake boxes via a bungee and a hook that fitted over the airbrake
pivot bar. The sting was pulled gently as the bag was pushed into the
wing. The string helped to prevent the bags getting bunched and
twisted when the wing was in the trailer.

Using this method I could extract, inspect, and replace each bag in
about 30 minutes single handed.

My picollo pipes were only about a third of the bag length. If I ever
have bags again the picollo pipes will be full bag length and then no
external pipe will be required for insertion.

Caution - if the bags have a string that exits through a hole in the
wing be careful when extracting the bag. Pull too fast and the string
will cut into whatever part it rubs on. I used a length of PCV tube
as a string guide.

Andy