Grob Twin Astir

On Thursday, January 28, 2016 at 10:56:01 PM UTC-5, K m wrote:
Group,
My club is looking to convert a Twin Astir brake system to a Hydraulic Disk from a Mechanical Drum. Our serial number does not fall within the serial number range of the Kit that is offered by Lindner. We have the Lindner kit and will be going with a 337. My question is does anyone know of a 337 on an Astir brake mod? Also, I have been trying to find info on any different versions of the Astir and can't find much. Is there any reference online that points to different models or versions? Ive read that water ballast was an option and some models came with a disk brake from the factory (These have a different wheel carrier structure). Does anyone know if gross weights remained the same on the Astir through the production run? This info may hel when submitting paperwork to the FAA.
Thanks!

My club (Franconia Soaring) is looking for a replacement rear canopy for our G103 Twin Astir (serial number 3069). Can anyone help, or point me in the right direction?
Thanks !

My club (Franconia Soaring) is looking for a replacement rear canopy
for
ou=
r G103 Twin Astir (serial number 3069). Can anyone help, or point
me in
the=
right direction?
Thanks !

Lindner has canopy blanks in stock, and can ship quickly. Our club
(Nutmeg Soaring in Freehold,NY) might be looking to replace both a
front and rear canopy on a Twin Astir over the coming winter.
Shipping the canopies nested/spooned together greatly reduces the
shipping price per canopy. You can email me directly if you want to
explore the options. mropitz1 at aol dot com
Mike Opitz

On Tuesday, September 27, 2016 at 9:15:04 PM UTC-4, Michael Opitz wrote:
My club (Franconia Soaring) is looking for a replacement rear canopy
for
ou=
r G103 Twin Astir (serial number 3069). Can anyone help, or point
me in
the=
right direction?
Thanks !

Lindner has canopy blanks in stock, and can ship quickly. Our club
(Nutmeg Soaring in Freehold,NY) might be looking to replace both a
front and rear canopy on a Twin Astir over the coming winter.
Shipping the canopies nested/spooned together greatly reduces the
shipping price per canopy. You can email me directly if you want to
explore the options. mropitz1 at aol dot com
Mike Opitz

Thanks Mike... I just wrote to you at aol
-Andy-

At 06:46 19 February 2016, wrote:
Have you tried rebuilding the drum brake? My club used to have a
Twin
Astir=
retractable and the drum - tiny though it looked - always did a fair
job
o=
f stopping the ship. It was strong enough to make rubbing the
underside of
=
the nose on the runway a concern.

Very true, the original Grob 103 Twin Astir had no nosewheel so a
super efficient brake is not a good idea, unless of course you want to
grind off the gel coat, or even worse the underlying structure under
the nose. The Grob103 Acro did have a nosewheel and therefore the
more efficient disc brake was not a problem.
I always wonder if people actually think through the implications of
making something "better". Perhaps there was a reason why the
original design did not have a super efficient brake.
Duct tape can't fix stupid, it can muffle the noise.

It's ironic that the I received an email from the Utah Soaring Association indicating yesterday telling about one of our Grob Astir's had a hard landing a few weeks ago that ripped off the disk brake caliper. The damage inspection found this is not the first time this has happened as the caliper hangs down at the 6 o'clock position. The Utah board is looking at taking it back to the original drum brake design for better hard landing durability.

Robert Mudd in Moriarty was very helpful when we needed a canopy last year. There are a few different sub-versions, so it's important to make sure you know exactly which frame you have.

P3

At 09:59 28 September 2016, Don Johnstone wrote:
At 06:46 19 February 2016, wrote:
Have you tried rebuilding the drum brake? My club used to have
a
Twin
Astir=
retractable and the drum - tiny though it looked - always did a
fair
job
o=
f stopping the ship. It was strong enough to make rubbing the
underside of
=
the nose on the runway a concern.

Very true, the original Grob 103 Twin Astir had no nosewheel so a
super efficient brake is not a good idea, unless of course you want
to
grind off the gel coat, or even worse the underlying structure
under
the nose. The Grob103 Acro did have a nosewheel and therefore
the
more efficient disc brake was not a problem.
I always wonder if people actually think through the implications
of
making something "better". Perhaps there was a reason why the
original design did not have a super efficient brake.
Duct tape can't fix stupid, it can muffle the noise.

The Twin Astir Trainer (fixed gear version) came with a standard
hydraulic disc brake from the factory. The ones which people are
retrofitting are the more numerous retractable gear versions. There
was a problem with that disc being too thin and deforming, but
TOST put out a retrofit kit to fix that issue last year.

I view the extra stopping power of the disc brake as another tool in
my toolbox of flight controls. I don't use all of its capabilities under
normal conditions, but if a situation occurs where I need that power, I
want to be able to access it NOW. For example, if I have a
low altitude rope break and am forced into a situation where there is
not much room to stop, I (personally) would rather get on the brake
hard (even if it means scraping the nose) in order to avoid being
forced to make an intentional ground loop (and breaking the tail
boom +) to avoid a looming obstacle.

I flew professionally for 42 years, and it always grated on me when
someone took a useful tool out of my toolbox "for my own good".

Whether one is a pilot, cabinet maker, electrician or whatever, one
has tools to ply one's trade. Some of those tools will have the
capability to kill or maim. It is the responsibility of the OPERATOR to
use those provided tools with skill, accuracy and judgement. Don't
blame the tool, when the problem is in reality an inept operator....

RO

Michael-

Hear Hear!

On Thursday, September 29, 2016 at 3:15:10 PM UTC+13, Michael Opitz wrote:
At 09:59 28 September 2016, Don Johnstone wrote:
At 06:46 19 February 2016, wrote:
Have you tried rebuilding the drum brake? My club used to have
a
Twin
Astir=
retractable and the drum - tiny though it looked - always did a
fair
job
o=
f stopping the ship. It was strong enough to make rubbing the
underside of
=
the nose on the runway a concern.

Very true, the original Grob 103 Twin Astir had no nosewheel so a
super efficient brake is not a good idea, unless of course you want
to
grind off the gel coat, or even worse the underlying structure
under
the nose. The Grob103 Acro did have a nosewheel and therefore
the
more efficient disc brake was not a problem.
I always wonder if people actually think through the implications
of
making something "better". Perhaps there was a reason why the
original design did not have a super efficient brake.
Duct tape can't fix stupid, it can muffle the noise.

The Twin Astir Trainer (fixed gear version) came with a standard
hydraulic disc brake from the factory. The ones which people are
retrofitting are the more numerous retractable gear versions. There
was a problem with that disc being too thin and deforming, but
TOST put out a retrofit kit to fix that issue last year.

I view the extra stopping power of the disc brake as another tool in
my toolbox of flight controls. I don't use all of its capabilities under
normal conditions, but if a situation occurs where I need that power, I
want to be able to access it NOW. For example, if I have a
low altitude rope break and am forced into a situation where there is
not much room to stop, I (personally) would rather get on the brake
hard (even if it means scraping the nose) in order to avoid being
forced to make an intentional ground loop (and breaking the tail
boom +) to avoid a looming obstacle.

I flew professionally for 42 years, and it always grated on me when
someone took a useful tool out of my toolbox "for my own good".

Whether one is a pilot, cabinet maker, electrician or whatever, one
has tools to ply one's trade. Some of those tools will have the
capability to kill or maim. It is the responsibility of the OPERATOR to
use those provided tools with skill, accuracy and judgement. Don't
blame the tool, when the problem is in reality an inept operator....

Y'know ... when I learned to fly, we were *taught* to use the nose of the Blanik on the ground for extra braking in an emergency. It's a long time ago, but I seem to recall it may even have been demonstrated.

At 02:02 29 September 2016, Michael Opitz wrote:
At 09:59 28 September 2016, Don Johnstone wrote:
At 06:46 19 February 2016, wrote:
Have you tried rebuilding the drum brake? My club used to have
a
Twin
Astir=
retractable and the drum - tiny though it looked - always did a
fair
job
o=
f stopping the ship. It was strong enough to make rubbing the
underside of
=
the nose on the runway a concern.

Very true, the original Grob 103 Twin Astir had no nosewheel so a
super efficient brake is not a good idea, unless of course you want
to
grind off the gel coat, or even worse the underlying structure
under
the nose. The Grob103 Acro did have a nosewheel and therefore
the
more efficient disc brake was not a problem.
I always wonder if people actually think through the implications
of
making something "better". Perhaps there was a reason why the
original design did not have a super efficient brake.
Duct tape can't fix stupid, it can muffle the noise.

The Twin Astir Trainer (fixed gear version) came with a standard
hydraulic disc brake from the factory. The ones which people are
retrofitting are the more numerous retractable gear versions. There
was a problem with that disc being too thin and deforming, but
TOST put out a retrofit kit to fix that issue last year.

I view the extra stopping power of the disc brake as another tool in
my toolbox of flight controls. I don't use all of its capabilities under

normal conditions, but if a situation occurs where I need that power,
want to be able to access it NOW. For example, if I have a
low altitude rope break and am forced into a situation where there is
not much room to stop, I (personally) would rather get on the brake
hard (even if it means scraping the nose) in order to avoid being
forced to make an intentional ground loop (and breaking the tail
boom +) to avoid a looming obstacle.

I flew professionally for 42 years, and it always grated on me when
someone took a useful tool out of my toolbox "for my own good".

Whether one is a pilot, cabinet maker, electrician or whatever, one
has tools to ply one's trade. Some of those tools will have the
capability to kill or maim. It is the responsibility of the OPERATOR to
use those provided tools with skill, accuracy and judgement. Don't
blame the tool, when the problem is in reality an inept operator....

RO

I would agree with you IF gliders, especially 2 seat gliders were always
flown by pilots experience as you and I. Truth is they are not, they are
frequently flown by very inexperienced and sometimes inept pilots, that is
the nature of gliding. The wheel brake on a glider is not a mission
critical item, unlike a powered aircraft the brakes are not tested before
taxiing, in most cases we only find they do not work on landing which is
why I never rely on them. I accept a good brake may be best in the
situation you describe but that occurs rarely. The risk of damage by a nose
over is much greater and more common. One of those cases where the cure is
worse than the disease. I do accept that the Twin Astir is very tail heavy
and almost impossible to nose down with the OEM brake, not so with a more
efficient disc brake.