Fatal crash Arizona

On Saturday, May 3, 2014 9:27:10 PM UTC-7, Waveguru wrote:
Premature termination of the tow at 100ft. Did not complete the turn back to the runway.



http://www.kathrynsreport.com/2014/0...izona.html?m=1



Boggs

UPDATE..... http://www.abc15.com/news/region-cen...a-glider-crash

Glider was a Zuni. Crash not observed by any glider pilots. Tow pilot felt the sudden lack of pull behind him, circled back and observed the wreckage a bit east of the runway among homes and bushes. Bummer day.

Retired Major General Robert Knauff had nearly 4,000 hours flight time, but was fairly new to soaring. He bought his Zuni last year, was checked out and did his first flight at Tucson Soaring Club. In the past week, he flew four decent cross-country flights from Sampley's airport and was reportedly really getting into flying it.

No club members witnessed the accident, but it occurred after a presumably unintentional tow release at around 100 feet.

Article from his home town he

http://www.syracuse.com/news/index.s...der_crash.html

Mike

Glider was a Zuni. Crash not observed by any glider pilots. Tow pilot felt the sudden lack of pull behind him, circled back and observed the wreckage a bit east of the runway among homes and bushes. Bummer day.


My condolences to the family and friends of Mr. Knauff.
Is it known whether the tow rope failed or did it come out of the release? Just curious.
Uli

The rope was intact. We don't know what caused the release. I'm not even sure we know if he turned back or rotated 180 during the spin. No pilot saw what happened.

Boggs

On Tuesday, May 6, 2014 1:42:53 PM UTC-5, Waveguru wrote:
The rope was intact. We don't know what caused the release. I'm not even sure we know if he turned back or rotated 180 during the spin. No pilot saw what happened.



Boggs

I heard Tom Knauff speak at the Senior Soaring Championships in March about in flight medical issues. (A great presentation by the way.)

One possibility is that Bob Knauff was experiencing a medical emergency and, in a last act of heroism, released to save the tow pilot.

We may never know but if this is the case, hats off to General Knauff.

Lou

While in no way do I wish to speculate on the cause of this accident or
indeed suggest that my comments in any way address the cause of this
accident.
I feel that comment is needed on some of the things said here. We have a
rule here in the UK, launch failure on aerotow below 300ft a landing should
be made ahead, or slightly to one side. No attempt should be made to turn
back below this height.
The reason is simple, a controlled crash into difficult terrain is likely
to result in a better outcome than an uncontrolled arrival on the airfield.
The important bit to keep intact is the bit you are sitting in, the rest of
the glider does not really matter too much. The best chance of achieving
that is flying to the ground with the wings level. It has only happened to
me once, there was a field ahead but it was full of the Tiger Moth tug that
had landed in the middle. I discovered that there was just enough space for
a Skylark 2 as well. I have no doubt that a turn back would have resulted
in an accident. I was at 250ft agl max.
If there really is nowhere to land ahead you should really ask the
question, "should I be taking a launch".
Frankly I would be horrified to be required to conduct a turn back at
200ft, I would suggest that this is one of those occasions where the danger
of practice is to great to justify.

On Tuesday, May 6, 2014 1:41:23 PM UTC-7, Don Johnstone wrote:
While in no way do I wish to speculate on the cause of this accident or

indeed suggest that my comments in any way address the cause of this

accident.

I feel that comment is needed on some of the things said here. We have a

rule here in the UK, launch failure on aerotow below 300ft a landing should

be made ahead, or slightly to one side. No attempt should be made to turn

back below this height.

The reason is simple, a controlled crash into difficult terrain is likely

to result in a better outcome than an uncontrolled arrival on the airfield.

The important bit to keep intact is the bit you are sitting in, the rest of

the glider does not really matter too much. The best chance of achieving

that is flying to the ground with the wings level. It has only happened to

me once, there was a field ahead but it was full of the Tiger Moth tug that

had landed in the middle. I discovered that there was just enough space for

a Skylark 2 as well. I have no doubt that a turn back would have resulted

in an accident. I was at 250ft agl max.

If there really is nowhere to land ahead you should really ask the

question, "should I be taking a launch".

Frankly I would be horrified to be required to conduct a turn back at

200ft, I would suggest that this is one of those occasions where the danger

of practice is to great to justify.

I have also voiced my concern at this tow termination training. Most times, it is a planned event and the towplane flies a modified pattern to give the trainee the best opportunity of returning to the launch runway. I have done several of these and they are not problematic. They also don't much resemble what happens in the real world when a rope break or disconnect is unplanned.

I have had only one of these in nearly 50 years of gliding. In one of my biannual tests, the instructor reassured me that no low altitude rope breaks would be simulated and then pulled the plug on me at a hair under 200 feet. Being unplanned. my reaction time was much longer - you have to work through the "holy ****, the tow rope's gone" thought process before taking any action. I landed successfully, but not on the departure runway - a story for another day. it did teach me that I didn't want a rope break under 200 feet and preferably not under 500 feet!

I have had several ropes break on the initial acceleration but none in the air. I have had three tugs lose power - two on the take-off run and one during climb-out. From my experience, I am skeptical that rope breaks between take-off and 200 feet are common enough to warrant the attention and training they get here in the USA..

I can also comment on the weather the day of the accident. It was perhaps one of the strongest (and highest) blue days I have seen in Arizona. The atmosphere was stable and dry under a dominant high-pressure system. Thermals were created by heating the air so much it had to rise, but these conditions resulted in very narrow, very strong, often multi-core, thermals surrounded by vicious sink and turbulence. These can be challenging if encountered on tow and can rapidly erode any height margin you have. You can expect to bash your head a few times (and perhaps your shins) on a day like this.. Good when you're high, but nasty below pattern altitude.

Mike

On Tuesday, May 6, 2014 4:08:26 PM UTC-6, Mike the Strike wrote:
On Tuesday, May 6, 2014 1:41:23 PM UTC-7, Don Johnstone wrote:

While in no way do I wish to speculate on the cause of this accident or



indeed suggest that my comments in any way address the cause of this



accident.



I feel that comment is needed on some of the things said here. We have a



rule here in the UK, launch failure on aerotow below 300ft a landing should



be made ahead, or slightly to one side. No attempt should be made to turn



back below this height.



The reason is simple, a controlled crash into difficult terrain is likely



to result in a better outcome than an uncontrolled arrival on the airfield.



The important bit to keep intact is the bit you are sitting in, the rest of



the glider does not really matter too much. The best chance of achieving



that is flying to the ground with the wings level. It has only happened to



me once, there was a field ahead but it was full of the Tiger Moth tug that



had landed in the middle. I discovered that there was just enough space for



a Skylark 2 as well. I have no doubt that a turn back would have resulted



in an accident. I was at 250ft agl max.



If there really is nowhere to land ahead you should really ask the



question, "should I be taking a launch".



Frankly I would be horrified to be required to conduct a turn back at



200ft, I would suggest that this is one of those occasions where the danger



of practice is to great to justify.



I have also voiced my concern at this tow termination training. Most times, it is a planned event and the towplane flies a modified pattern to give the trainee the best opportunity of returning to the launch runway. I have done several of these and they are not problematic. They also don't much resemble what happens in the real world when a rope break or disconnect is unplanned.



I have had only one of these in nearly 50 years of gliding. In one of my biannual tests, the instructor reassured me that no low altitude rope breaks would be simulated and then pulled the plug on me at a hair under 200 feet. Being unplanned. my reaction time was much longer - you have to work through the "holy ****, the tow rope's gone" thought process before taking any action. I landed successfully, but not on the departure runway - a story for another day. it did teach me that I didn't want a rope break under 200 feet and preferably not under 500 feet!



I have had several ropes break on the initial acceleration but none in the air. I have had three tugs lose power - two on the take-off run and one during climb-out. From my experience, I am skeptical that rope breaks between take-off and 200 feet are common enough to warrant the attention and training they get here in the USA..



I can also comment on the weather the day of the accident. It was perhaps one of the strongest (and highest) blue days I have seen in Arizona. The atmosphere was stable and dry under a dominant high-pressure system. Thermals were created by heating the air so much it had to rise, but these conditions resulted in very narrow, very strong, often multi-core, thermals surrounded by vicious sink and turbulence. These can be challenging if encountered on tow and can rapidly erode any height margin you have. You can expect to bash your head a few times (and perhaps your shins) on a day like this. Good when you're high, but nasty below pattern altitude.



Mike

Mike,

Turns do not cause stall/spin accidents. In fact, the steeper the turn, the greater the stall margin. That's because elevator authority is progressively used up making the glider turn as the bank gets steeper until the angle of attack can't be raised above stall. Try it. You'll find many gliders will run out of up elevator before they can be stalled at bank angles over 45 degrees.

Low turns don't cause stall spins either - they just insure there will be a permanent record should one occur. Pilots spin gliders unintentionally at higher altitudes too but they don't tell anybody.

Spins happen because the pilot stalled the glider, not because the pilot was turning.

The root cause of stall/spin accidents is pilot incompetence although it may not be their fault. Pilot training in gliders skips over an important area that is well covered in airplane training - its called ground reference maneuvers. If a student is drilled in low turns, it's less likely they will spin in on turns to final.

On Tuesday, May 6, 2014 2:41:23 PM UTC-6, Don Johnstone wrote:

Frankly I would be horrified to be required to conduct a turn back at

200ft, I would suggest that this is one of those occasions where the danger

of practice is to great to justify.

If you should check out in the USA, you'll be required to demonstrate competence in this maneuver. Every pre-solo student is required to do so and more than a half century of safety records do not suggest a problem. In fact, even with low performance gliders, there's quite a large safety margin. The most likely outcome is a pilot will find the glider uncomfortably high for a downwind landing requiring full spoilers and a slip.

The logic is simple - it's better to have pilots trained for the option. No one says a pilot is required to turn back or that 200' is always adequate to do so. What is illogical is to suggest a pilot be required to crash in unlandable terrain when a safe option exists to land on the departure runway.

At 22:22 06 May 2014, Bill D wrote:
On Tuesday, May 6, 2014 2:41:23 PM UTC-6, Don Johnstone wrote:

Frankly I would be horrified to be required to conduct a turn back at
=20
200ft, I would suggest that this is one of those occasions where the
dang=
er
=20
of practice is to great to justify.

If you should check out in the USA, you'll be required to demonstrate
compe=
tence in this maneuver. Every pre-solo student is required to do so and
mo=
re than a half century of safety records do not suggest a problem. In
fact=
, even with low performance gliders, there's quite a large safety margin.
T=
he most likely outcome is a pilot will find the glider uncomfortably high
f=
or a downwind landing requiring full spoilers and a slip.

The logic is simple - it's better to have pilots trained for the option.
N=
o one says a pilot is required to turn back or that 200' is always
adequate=
to do so. What is illogical is to suggest a pilot be required to crash
in=
unlandable terrain when a safe option exists to land on the departure
runw=
ay.

What are you trying to save? The pilot or the aircraft? The priority should
be survival of the soft bit, that is you and me.
As an instructor with nearly 50 years experience I know that when I
initiate an emergency procedure I do so allowing a margin to ensure my
survival if it does not work out, I have been bold but never certifiable.
Most living instructors have the same survival instinct. That is why I have
lived long enough to do 10,000 launches, and of course landings. It has
already been hinted that the practice you describe involves modifying what
you normally do, in my view that probably makes it pretty useless and not
real preparation for the event. If you did carry out the training in
exactly the same way as the possible real event you might find that the
results were very different, not to mention painful. 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, 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?
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.

PS Despite all that there have been times when I have initiated a practice
emergency and very quickly wished I had not, no plan survives first
contact.