Landing with reduced airbrake

from my perspective, reducing airbrakes at 100' changes your glide slope and therefor aim point half way through final. So do you give up your initial aim point at 100', or do you have two aim points? Either option seems like a bad idea for students.

Airbrake deployment should be a driven variable to maintain a correct approach, not the other way around.

Additionally, a shallower approach for the last 100' means you are way more susceptible to wind shear, as you don't have much "extra" glide to recover by closing the airbrakes.

To me, it sounds like the tail strike problem is in the flair, not the use of airbrakes.

The DG-1000 Club seems a good illustration of the law of unintended consequences. Having the fixed gear as far down as the retractable version would impose a significant drag penalty, but having it higher up imposes a higher takeoff and touchdown speed.

The electric gear version can fail to come down. The flight manual recommends practicing the emergency gear down mechanism periodically. I know of one gear up landing where the Instructor had not practiced the emergency gear down.

On Thursday, 17 May 2018 06:58:54 UTC+8, George Haeh wrote:
The DG-1000 Club seems a good illustration of the law of unintended consequences. Having the fixed gear as far down as the retractable version would impose a significant drag penalty, but having it higher up imposes a higher takeoff and touchdown speed.

The electric gear version can fail to come down. The flight manual recommends practicing the emergency gear down mechanism periodically. I know of one gear up landing where the Instructor had not practiced the emergency gear down.

This is what I think too - the original design had the high main-wheel but people wanted easier cockpit access so they gave it the lower main/nose wheel combination .. which has compromised the landing attitude. All well & good, but it does now expose the tail-wheel to some serious abuse by students! I guess any "do everything" performance glider is going to be compromised to some extent - in this case as a club ab-initio trainer. I still think the best mitigation (as an instructor) is to actively limit the rate of descent if required.

On Wednesday, 16 May 2018 22:21:48 UTC+8, Matt Herron Jr. wrote:
from my perspective, reducing airbrakes at 100' changes your glide slope and therefor aim point half way through final. So do you give up your initial aim point at 100', or do you have two aim points? Either option seems like a bad idea for students.

Airbrake deployment should be a driven variable to maintain a correct approach, not the other way around.

Additionally, a shallower approach for the last 100' means you are way more susceptible to wind shear, as you don't have much "extra" glide to recover by closing the airbrakes.

To me, it sounds like the tail strike problem is in the flair, not the use of airbrakes.

Hi Matt, yes you give up the original aim point. This isn't ideal but better than damaging the aircraft? The debrief can cover off the reasons. Lots of bad landings are the result of not accepting that you stuffed up your original aiming point & concentrating on the actual landing.

On Thursday, May 17, 2018 at 1:43:09 PM UTC+12, Richard McLean wrote:
On Wednesday, 16 May 2018 22:21:48 UTC+8, Matt Herron Jr. wrote:
from my perspective, reducing airbrakes at 100' changes your glide slope and therefor aim point half way through final. So do you give up your initial aim point at 100', or do you have two aim points? Either option seems like a bad idea for students.

Airbrake deployment should be a driven variable to maintain a correct approach, not the other way around.

Additionally, a shallower approach for the last 100' means you are way more susceptible to wind shear, as you don't have much "extra" glide to recover by closing the airbrakes.

To me, it sounds like the tail strike problem is in the flair, not the use of airbrakes.

Hi Matt, yes you give up the original aim point. This isn't ideal but better than damaging the aircraft? The debrief can cover off the reasons. Lots of bad landings are the result of not accepting that you stuffed up your original aiming point & concentrating on the actual landing.

I'd think if you were so high turning final that you can't get back on to a standard half brake approach by, say, 100m before crossing the fence then you've well and truly stuffed up the circuit. Especially in something with airbrakes as powerful as a DG1000 or Grob. You definitely should never be planning to carry full brake all the way down the approach ... that leave nothing in reserve for the unexpected.

At 06:36 17 May 2018, Bruce Hoult wrote:
On Thursday, May 17, 2018 at 1:43:09 PM UTC+12, Richard McLean wrote:
On Wednesday, 16 May 2018 22:21:48 UTC+8, Matt Herron Jr. wrote:
from my perspective, reducing airbrakes at 100' changes your glide
slop=
e and therefor aim point half way through final. So do you give up your
in=
itial aim point at 100', or do you have two aim points? Either option
seem=
s like a bad idea for students.
=20
Airbrake deployment should be a driven variable to maintain a correct
a=
pproach, not the other way around.
=20
Additionally, a shallower approach for the last 100' means you are
way
=
more susceptible to wind shear, as you don't have much "extra" glide to
rec=
over by closing the airbrakes.
=20
To me, it sounds like the tail strike problem is in the flair, not
the
=
use of airbrakes.
=20
Hi Matt, yes you give up the original aim point. This isn't ideal but
bet=
ter than damaging the aircraft? The debrief can cover off the reasons.
Lots=
of bad landings are the result of not accepting that you stuffed up your
o=
riginal aiming point & concentrating on the actual landing.

I'd think if you were so high turning final that you can't get back on to
a=
standard half brake approach by, say, 100m before crossing the fence
then
=
you've well and truly stuffed up the circuit. Especially in something
with
=
airbrakes as powerful as a DG1000 or Grob. You definitely should never be
p=
lanning to carry full brake all the way down the approach ... that leave
no=
thing in reserve for the unexpected.

Trick one
I have not flown the DG1001 neo yet but I have quite a lot of time in the
original DG1000,you need a step to get people in,if that is the angle for
2point landing them the newer versions going to land tail wheel first .

I have done hundreds of trial flights in an early DG500 that everyone said
was "over braked" ,in fact it could be .But as all I wanted was to get the
punters down safe without a hard landing I tend to add 5kns and gently fly
it on, on the main wheel.
The trouble with that is its not the correct method to teach landing to
pupils.

As I said tricky
My advice would be to buy a K21 or Duo xl ,they fly as you would expect.

On Thursday, May 17, 2018 at 9:00:15 PM UTC+12, Jonathon May wrote:
At 06:36 17 May 2018, Bruce Hoult wrote:
On Thursday, May 17, 2018 at 1:43:09 PM UTC+12, Richard McLean wrote:
On Wednesday, 16 May 2018 22:21:48 UTC+8, Matt Herron Jr. wrote:
from my perspective, reducing airbrakes at 100' changes your glide
slop=
e and therefor aim point half way through final. So do you give up your
in=
itial aim point at 100', or do you have two aim points? Either option
seem=
s like a bad idea for students.
=20
Airbrake deployment should be a driven variable to maintain a correct
a=
pproach, not the other way around.
=20
Additionally, a shallower approach for the last 100' means you are
way
=
more susceptible to wind shear, as you don't have much "extra" glide to
rec=
over by closing the airbrakes.
=20
To me, it sounds like the tail strike problem is in the flair, not
the
=
use of airbrakes.
=20
Hi Matt, yes you give up the original aim point. This isn't ideal but
bet=
ter than damaging the aircraft? The debrief can cover off the reasons.
Lots=
of bad landings are the result of not accepting that you stuffed up your
o=
riginal aiming point & concentrating on the actual landing.

I'd think if you were so high turning final that you can't get back on to
a=
standard half brake approach by, say, 100m before crossing the fence
then
=
you've well and truly stuffed up the circuit. Especially in something
with
=
airbrakes as powerful as a DG1000 or Grob. You definitely should never be
p=
lanning to carry full brake all the way down the approach ... that leave
no=
thing in reserve for the unexpected.

Trick one
I have not flown the DG1001 neo yet but I have quite a lot of time in the
original DG1000,you need a step to get people in,if that is the angle for
2point landing them the newer versions going to land tail wheel first .

I have done hundreds of trial flights in an early DG500 that everyone said
was "over braked" ,in fact it could be .But as all I wanted was to get the
punters down safe without a hard landing I tend to add 5kns and gently fly
it on, on the main wheel.
The trouble with that is its not the correct method to teach landing to
pupils.

As I said tricky
My advice would be to buy a K21 or Duo xl ,they fly as you would expect.

Not necessary. All you need to do is fly close to the ground and gradually slow and increase the pitch until you are in the same attitude as you would be on the ground.

Assuming you have levelled out at the correct height for your undercarriage length it all works out just the same as any other glider. Main wheel is skimming just a few inches above the ground, once the AOA gets to the point that the tail wheel touches gently you physically can't increase the pitch more, and do the main will gently drop on.

Whether the glider is actually "stalled" at that point or not is irrelevant..

If you level out a DG1000 Club at the same height as you would a standard DG1000, and then slow until it stalls, then you're going to be dropping on hard from a foot up no matter what you do. Know how it looks out the window of your glider when it's on the ground!

At 01:40 18 May 2018, Bruce Hoult wrote:
On Thursday, May 17, 2018 at 9:00:15 PM UTC+12, Jonathon May
wrote:
At 06:36 17 May 2018, Bruce Hoult wrote:
On Thursday, May 17, 2018 at 1:43:09 PM UTC+12, Richard
McLean wrote:
On Wednesday, 16 May 2018 22:21:48 UTC+8, Matt Herron Jr.
wrote:
from my perspective, reducing airbrakes at 100' changes your
glide
slop=3D
e and therefor aim point half way through final. So do you give up
your
in=3D
itial aim point at 100', or do you have two aim points? Either
option
seem=3D
s like a bad idea for students.
=3D20
Airbrake deployment should be a driven variable to maintain a
correc=
t
a=3D
pproach, not the other way around.
=3D20
Additionally, a shallower approach for the last 100' means you
are
way
=3D
more susceptible to wind shear, as you don't have much "extra"
glide to
rec=3D
over by closing the airbrakes.
=3D20
To me, it sounds like the tail strike problem is in the flair, not
the
=3D
use of airbrakes.
=3D20
Hi Matt, yes you give up the original aim point. This isn't ideal
but
bet=3D
ter than damaging the aircraft? The debrief can cover off the
reasons.
Lots=3D
of bad landings are the result of not accepting that you stuffed up
you=
r
o=3D
riginal aiming point & concentrating on the actual landing.

I'd think if you were so high turning final that you can't get back
on
t=
o
a=3D
standard half brake approach by, say, 100m before crossing the
fence
then
=3D
you've well and truly stuffed up the circuit. Especially in something
with
=3D
airbrakes as powerful as a DG1000 or Grob. You definitely should
never
b=
e
p=3D
lanning to carry full brake all the way down the approach ... that
leave
no=3D
thing in reserve for the unexpected.
=20
Trick one
I have not flown the DG1001 neo yet but I have quite a lot of time in
the
original DG1000,you need a step to get people in,if that is the
angle
f=
or
2point landing them the newer versions going to land tail wheel first