Fatal crash Arizona

On Sunday, June 15, 2014 12:09:22 AM UTC-6, 2G wrote:

PLEASE stop with the sanctimonious crap! I have done hundreds of aerotows.. You need to lower the nose because you are in a climb attitude and need to transition to a glide attitude. On your next tow note where the horizon is on the canopy and compare it to where it is after release at the same airspeed.
---------------------------
Raise, lower or leave the nose where it is - this is an energy management maneuver. The pilot is trying to make the most of the energy he has available when the rope breaks not follow some rote procedure.

If the glider remains at the climb attitude the airspeed will be trending down which is just fine for the moment since the tow airspeed is very likely to have been well above best L/D or even pattern speed. Until safe return to the runway is assured, stabilizing the airspeed at best L/D is the target. Once return is assured, the pilot may elect to accelerate to pattern speed.

The basic airmanship skill is monitoring airspeed trends while simultaneously maneuvering the glider for landing. Once stabilized at best L/D, if the airspeed is climbing, the nose is too low. If the airspeed is falling, it's too high.

On Sunday, June 15, 2014 3:11:29 PM UTC-7, Bill D wrote:
On Sunday, June 15, 2014 12:09:22 AM UTC-6, 2G wrote:



PLEASE stop with the sanctimonious crap! I have done hundreds of aerotows. You need to lower the nose because you are in a climb attitude and need to transition to a glide attitude. On your next tow note where the horizon is on the canopy and compare it to where it is after release at the same airspeed.

---------------------------

Raise, lower or leave the nose where it is - this is an energy management maneuver. The pilot is trying to make the most of the energy he has available when the rope breaks not follow some rote procedure.



If the glider remains at the climb attitude the airspeed will be trending down which is just fine for the moment since the tow airspeed is very likely to have been well above best L/D or even pattern speed. Until safe return to the runway is assured, stabilizing the airspeed at best L/D is the target. Once return is assured, the pilot may elect to accelerate to pattern speed.



The basic airmanship skill is monitoring airspeed trends while simultaneously maneuvering the glider for landing. Once stabilized at best L/D, if the airspeed is climbing, the nose is too low. If the airspeed is falling, it's too high.

Come on, get REAL! If this were the case there would be no such accidents!

Actual pilots, when confronted with actual emergencies, do not always respond the way they are taught. Why do pilots stall AT ALL if they did what you suggested? Your arm chair analytical review is NOT WORKING!

I am strongly suggesting that there are irrational emotional factors that influence pilots to do things completely contrary to their training. I know this for a fact; disregarding this reality is to put your head into the sand.

At least you have stopped denigrating my motorglider experience.

Tom

On Wednesday, May 7, 2014 1:20:44 PM UTC+12, Bill D wrote:
I can assure you that the higher a glider's performance, the safer it is. It's the old, low L/D gliders that can run out of altitude before getting lined up with the runway.

It's a mystery to me why some people think you can "get away with" so much more in old gliders than in those great big heavy clumsy glass ones.

Somewhere in this thread I saw a statement that you could safely turn back from 150 ft in an old glider (which I agree with), but you're a dead man if you try it below 300 ft in glass.

The differences that govern such a thing just aren't that big!

Let's look at some numbers for weight and wing area of typical training gliders (from Wikipedia):

ASK13: 290 kg, 17.5 m^2
Blanik L13: 292 kg, 19.15 m^2

PW6: 360 kg, 15.3 m^2
ASK21: 360 kg, 17.95 m^2
Puchacz: 368 kg, 18.16 m^2
Janus: 365 kg, 17.3 m^2

G103: 390 kg, 17.9 m^2
Duo Discus: 410 kg, 16.4 m^2
DG1000: 415 kg, 17.5 m^2

There's not a lot of difference in the wing areas, with individual variations bigger than the generational differences.

Yes, the glass ones weigh a bit more. How much more?

Someone flying solo in an ASK21 is at about the same all up weight as someone in a ASK13 with a smaller than average instructor in the back seat.

Someone flying solo in a DG1000 is at about the same all up weight as someone in a ASK13 with a largish instructor in the back seat.

We expect students to be able to cope with the flying characteristic differences between having an instructor and not having one -- and to cope with that difference on their first time flying alone!

At 02:06 09 May 2014, Bruce Hoult wrote:
On Wednesday, May 7, 2014 1:20:44 PM UTC+12, Bill D wrote:
I can assure you that the higher a glider's performance, the safer it
is.
It's the old, low L/D gliders that can run out of altitude before getting
lined up with the runway.

It's a mystery to me why some people think you can "get away with" so
much
more in old gliders than in those great big heavy clumsy glass ones.

Somewhere in this thread I saw a statement that you could safely turn
back
from 150 ft in an old glider (which I agree with), but you're a dead man
if
you try it below 300 ft in glass.

The differences that govern such a thing just aren't that big!

Let's look at some numbers for weight and wing area of typical training
gliders (from Wikipedia):

ASK13: 290 kg, 17.5 m^2
Blanik L13: 292 kg, 19.15 m^2

PW6: 360 kg, 15.3 m^2
ASK21: 360 kg, 17.95 m^2
Puchacz: 368 kg, 18.16 m^2
Janus: 365 kg, 17.3 m^2

G103: 390 kg, 17.9 m^2
Duo Discus: 410 kg, 16.4 m^2
DG1000: 415 kg, 17.5 m^2

There's not a lot of difference in the wing areas, with individual
variations bigger than the generational differences.

Yes, the glass ones weigh a bit more. How much more?

Someone flying solo in an ASK21 is at about the same all up weight as
someone in a ASK13 with a smaller than average instructor in the back
seat.

Someone flying solo in a DG1000 is at about the same all up weight as
someone in a ASK13 with a largish instructor in the back seat.

We expect students to be able to cope with the flying characteristic
differences between having an instructor and not having one -- and to
cope
with that difference on their first time flying alone!

I think you are missing the point. The difference between the perceived
attitude of a Discus flying at 45kts (too slow) or 55kts (much better) in a
turn is very small, easy to get wrong.
The perceived attitude difference in a T21 Sedburgh between 35kts (slow)
and 45kts(better) is quite large, easy to spot if you got it wrong. Bearing
in mind that a T21 would not stall until you got it back to 22-25kts made
low turns much more unexciting. The T21 and T31 are the gliders I was
referring to.
When it all turns to ratsh1t in a glass glider it happens that much more
quickly than it ever did in wood.

At 00:13 10 May 2014, Don Johnstone wrote:
At 02:06 09 May 2014, Bruce Hoult wrote:
On Wednesday, May 7, 2014 1:20:44 PM UTC+12, Bill D wrote:
I can assure you that the higher a glider's performance, the safer it
is.
It's the old, low L/D gliders that can run out of altitude before
getting
lined up with the runway.

It's a mystery to me why some people think you can "get away with" so
much
more in old gliders than in those great big heavy clumsy glass ones.

Somewhere in this thread I saw a statement that you could safely turn
back
from 150 ft in an old glider (which I agree with), but you're a dead man
if
you try it below 300 ft in glass.

The differences that govern such a thing just aren't that big!

Let's look at some numbers for weight and wing area of typical training
gliders (from Wikipedia):

ASK13: 290 kg, 17.5 m^2
Blanik L13: 292 kg, 19.15 m^2

PW6: 360 kg, 15.3 m^2
ASK21: 360 kg, 17.95 m^2
Puchacz: 368 kg, 18.16 m^2
Janus: 365 kg, 17.3 m^2

G103: 390 kg, 17.9 m^2
Duo Discus: 410 kg, 16.4 m^2
DG1000: 415 kg, 17.5 m^2

There's not a lot of difference in the wing areas, with individual
variations bigger than the generational differences.

Yes, the glass ones weigh a bit more. How much more?

Someone flying solo in an ASK21 is at about the same all up weight as
someone in a ASK13 with a smaller than average instructor in the back
seat.

Someone flying solo in a DG1000 is at about the same all up weight as
someone in a ASK13 with a largish instructor in the back seat.

We expect students to be able to cope with the flying characteristic
differences between having an instructor and not having one -- and to
cope
with that difference on their first time flying alone!

I think you are missing the point. The difference between the perceived
attitude of a Discus flying at 45kts (too slow) or 55kts (much better) in
a
turn is very small, easy to get wrong.
The perceived attitude difference in a T21 Sedburgh between 35kts (slow)
and 45kts(better) is quite large, easy to spot if you got it wrong.
Bearing
in mind that a T21 would not stall until you got it back to 22-25kts made
low turns much more unexciting. The T21 and T31 are the gliders I was
referring to.
When it all turns to ratsh1t in a glass glider it happens that much more
quickly than it ever did in wood.



All completely correct but there is one even bigger problem, most pilots
when making a low level turn off a launch failure or to modify a
circuit/pattern that has got too low, tend to be looking for/at the place
they intend to land with little or no attention to spare for the ASI,
attitude or slip/skid indicator, that's why these events are so productive
of stall/spin accidents. Training needs to emphasise, GLANCE AT THE ASI
EVERY 2 - 3 SECONDS IN THESE CIRCUMSTANCES. Attitude is un unreliable
indicator very near the ground, even the smallest undulations in the
terrain can give a false impression and just being low can make the
attitude look more nose down than it is.

At 07:20 10 May 2014, Chris Rollings wrote:
All completely correct but there is one even bigger problem, most pilots
when making a low level turn off a launch failure or to modify a
circuit/pattern that has got too low, tend to be looking for/at the place
they intend to land with little or no attention to spare for the ASI,
attitude or slip/skid indicator, that's why these events are so
productive
of stall/spin accidents. Training needs to emphasise, GLANCE AT THE ASI
EVERY 2 - 3 SECONDS IN THESE CIRCUMSTANCES. Attitude is un unreliable
indicator very near the ground, even the smallest undulations in the
terrain can give a false impression and just being low can make the
attitude look more nose down than it is.


Surely best practice is simply to keep the speed on until you have got it
all sorted. Certainly in modern slippery gliders. Too much speed is much
safer than too little and costs very little in height through a turn.

Isn't this what you taught us Chris?

On 5/10/2014 7:24 AM, Jim White wrote:
Certainly in modern slippery gliders. Too much speed is much
safer than too little and costs very little in height through a turn.

From the standpoint of preventing stalls, I can only agree. But if
your goal is to actually make it back to the runway, that advice should
be tempered with a bit more information!

Remember that turn radius increases with the SQUARE of airspeed. That
means that a small increase in airspeed will result in a significant
increase in turn radius. As the pilot, your goal in that situation
should be to shoot for the proper airspeed for the situation. Not too
much, but certainly always keeping a margin above stall speed.

By all means don't risk a stall! But remember that too much airspeed
could add to your troubles.

At 11:24 10 May 2014, Jim White wrote:
At 07:20 10 May 2014, Chris Rollings wrote:
All completely correct but there is one even bigger problem, most pilots
when making a low level turn off a launch failure or to modify a
circuit/pattern that has got too low, tend to be looking for/at the
place
they intend to land with little or no attention to spare for the ASI,
attitude or slip/skid indicator, that's why these events are so
productive
of stall/spin accidents. Training needs to emphasise, GLANCE AT THE ASI
EVERY 2 - 3 SECONDS IN THESE CIRCUMSTANCES. Attitude is un unreliable
indicator very near the ground, even the smallest undulations in the
terrain can give a false impression and just being low can make the
attitude look more nose down than it is.


Surely best practice is simply to keep the speed on until you have got it
all sorted. Certainly in modern slippery gliders. Too much speed is much
safer than too little and costs very little in height through a turn.

Isn't this what you taught us Chris?


Certainly a bit faster than optimum costs very little but you still need to
GLANCE AT THE ASI
EVERY 2 - 3 SECONDS IN THESE CIRCUMSTANCES to check what speed you are
doing.

On 5/6/2014 5:56 PM, Don Johnstone wrote:
Major Snip...

I will stick with my
300ft thank you, I know it works. Low turns, below that height may have
been acceptable in old wooden gliders, the minimum height in T31 and T21
gliders was 150ft, but for modern glass gliders it is just far too low...
Snip...

Volunteers for testing whether a lower-speed/higher-rate glider (T21/T31
certainly qualify) requires less height to execute a course reversal compared
to a higher speed/lower-sink rate modern plastic one? While testing, please do
contact the ground in controlled flight...

...you
only have to look at the accident statistics to see that low final turns
figure to a large degree in accidents so why plan for it?

Because: a) it happens (statistics); and b) (IMO) we reasonably safely can?
(That's certainly NOT the case when practicing the inadvertent departure from
controlled flight in the pattern.) And the skill might be good to have in
one's skill set? I'm not trying to be snarky, but it's the *uncontrolled*
ground contact that jumps out from the death statistics I've seen.

I repeat a controlled descent with wings level is far more likely to have a
better result than hitting the ground in a turn or even worse spinning in
trying to avoid it.

Roger both thoughts...especially that last one!

It's not "merely" the broken rope Joe Glider Pilot needs to be prepared for
as "the" source of an in-pattern prematurely terminated tow. Except for
training flights, I've never had an in-pattern premature tow termination...but
I know of lots of others who "for real" have, with causes including (off the
top of my head) unlatched canopies, passenger idiocy, improperly connected tow
rings and almost certainly more I'm forgetting.

Stuff happens. Prepare - mentally, training, muscle memory - accordionly.

Bob W.