Tragic Double Fatality?

[Gary Osoba]

Ck. Michael Graves' comments on his March 30, 2013 OLC flight posting.

Gary

[Paul Remde]

Hi Gary,

Wow. That is very tragic.
http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2854506
notes from the flight by Michael Graves copied below.

"Today we lost EDDIE HOGLAN, my best friend, and TAYLOR BROWN, my best
glider student, in an inflight wing failure on a Ka7. My club intentionally
did not call this news to me until I landed from my xc flight."

Paul Remde
_______________________________

"Gary Osoba" wrote in message
...

Ck. Michael Graves' comments on his March 30, 2013 OLC flight posting.

Gary

[Tom K (ES)]

http://www.kcbd.com/story/21840513/2-killed-in-littlefield-glider-crash

[Tom K (ES)]

https://www.facebook.com/RipTaylorBrown?fref=ts

[mike]

On Monday, April 1, 2013 8:08:45 AM UTC-6, Tom K (ES) wrote:
> https://www.facebook.com/RipTaylorBrown?fref=ts

Very sad.

[Tom K (ES)]

http://www.myfoxlubbock.com/news/local/story/Eddie-Hoglan-Taylor-James-Brown-Glider-crash/wCDe4frX_kqIlOpKzB1V2w.cspx

[Ramy]

On Tuesday, April 2, 2013 11:56:26 AM UTC-7, Tom K (ES) wrote:
> http://www.myfoxlubbock.com/news/local/story/Eddie-Hoglan-Taylor-James-Brown-Glider-crash/wCDe4frX_kqIlOpKzB1V2w.cspx

Horrible! Especially when a 13 years old perishes!

[Andrzej Kobus]

On Apr 2, 7:45*pm, Ramy > wrote:
> On Tuesday, April 2, 2013 11:56:26 AM UTC-7, Tom K (ES) wrote:
> >http://www.myfoxlubbock.com/news/local/story/Eddie-Hoglan-Taylor-Jame...
>
> Horrible! Especially when a 13 years old perishes!

One keeps wondering if a parachute would help. Did they have any?

Terrible loss for the community. Deepest sympathy for family and
friends. I got a 13 year old son. Hard to imagine such a loss.
Devastating...

[Sean F (F2)]

My god. I cannot imagine. So sorry to the families and friends of these pilots. Pit in my stomach, as with every one of these sad reports. I worry about old gliders out there.
Sean
F2

[Liam]

On Apr 2, 6:02*pm, "Sean F (F2)" > wrote:
> My god. *I cannot imagine. *So sorry to the families and friends of these pilots. *Pit in my stomach, as with every one of these sad reports. *I worry about old gliders out there.
> Sean
> F2

Looks like the Ka7 might become the new Blanik.

http://www.myplainview.com/news/article_6c582148-9c01-11e2-806c-0019bb2963f4.html

I wonder how many are still flying in the US?

[son_of_flubber]

On Wednesday, April 3, 2013 1:03:13 PM UTC-4, Liam wrote:

> Looks like the Ka7 might become the new Blanik.
> I wonder how many are still flying in the US?

There are only 3 registered in the USA and none in Texas, so 2 still flying

[Tony[_5_]]

On Wednesday, April 3, 2013 12:10:07 PM UTC-5, son_of_flubber wrote:
> On Wednesday, April 3, 2013 1:03:13 PM UTC-4, Liam wrote: > Looks like the Ka7 might become the new Blanik. > I wonder how many are still flying in the US? There are only 3 registered in the USA and none in Texas, so 2 still flying

There are 3 Schleicher K 7, 23 Schleicher Ka 7 and one Alexander Schleicher GMBH K 7.

I believe the Ka7 has a similar wing construction to the Ka2 and ASK-13; probably same wood and glue used in Ka6, Ka10, ASK14, and ASK18. There is some debate about what glue was used where in which gliders. It seems the factory was not consistent.

Of course this isn't necessarily a glue failure accident either. Time will tell.

[[email protected]]

There are actually 27 that I could find in the N-number registry. I did my training in one of them. This would be another enormous loss to our training community if in fact they are grounded.

http://registry.faa.gov/aircraftinquiry/Mms_Results.aspx?Mmstxt=3801551&conVal=0&PageNo=1

http://registry.faa.gov/aircraftinquiry/Mms_Results.aspx?Mmstxt=3801554&conVal=0&PageNo=1

http://registry.faa.gov/aircraftinquiry/NNum_Results.aspx?NNumbertxt=9156


On Wednesday, April 3, 2013 1:10:07 PM UTC-4, son_of_flubber wrote:
> On Wednesday, April 3, 2013 1:03:13 PM UTC-4, Liam wrote:
>
>
>
> > Looks like the Ka7 might become the new Blanik.
>
> > I wonder how many are still flying in the US?
>
>
>
> There are only 3 registered in the USA and none in Texas, so 2 still flying

[[email protected]]

> Looks like the Ka7 might become the new Blanik.
>
> http://www.myplainview.com/news/article_6c582148-9c01-11e2-806c-0019bb2963f4.html

According to the accident report for the 2004 accident referred to in this article, glue failure in the wing was dismissed as a reason for the wing failure. There was, however, an small glue failure in the left elevator that could have led to loss of control in pitch. The wing failure happened where the lower spar boom suffered first compression damage, then failed in tension, initiating the failure of the upper spar boom by bending. This compression damage could have occured in flight, by flying outside the flight envelope of the glider. It could not be established if this happened through loss of control due to elevator problems, or by voluntary maneuvres. The pilots had been discussing planned aerobatics before the flight, but the failure occured at the very beginning of the flight, during rolling maneuvres. Another possibility was that the compression damage occured during a heavy landing or the aircraft's recent excursion over rough ground that necessitated repairs to the steel tubing in the fuselage.

The complete report is available on the BGA website, but it is password protected. However, the Air Accidents Investigation Branch give the link, username and password on their links page: http://www.aaib.gov.uk/links/index.cfm

Look for report date: 25-11-2005

[Bob Kuykendall]

On Apr 3, 1:09*pm, wrote:

> The wing failure happened where the lower spar boom suffered first
> compression damage, then failed in tension, initiating the failure of
> the upper spar boom by bending...

This is a very common failure mode for wooden aircraft structures.
Often the event that caused the original compression damage precedes
the final failure by weeks or months or even years.

Thanks, Bob K.

[Ventus_a]

;836130']On Wednesday, April 3, 2013 12:10:07 PM UTC-5, son_of_flubber wrote:
On Wednesday, April 3, 2013 1:03:13 PM UTC-4, Liam wrote: Looks like the Ka7 might become the new Blanik. I wonder how many are still flying in the US? There are only 3 registered in the USA and none in Texas, so 2 still flying

There are 3 Schleicher K 7, 23 Schleicher Ka 7 and one Alexander Schleicher GMBH K 7.

I believe the Ka7 has a similar wing construction to the Ka2 and ASK-13; probably same wood and glue used in Ka6, Ka10, ASK14, and ASK18. There is some debate about what glue was used where in which gliders. It seems the factory was not consistent.

Of course this isn't necessarily a glue failure accident either. Time will tell.


FYI

Details of BGA inspections on K7 and others

http://www.gliding.co.uk/bgainfo/technical/inspections/042-07-2004-issue-3.pdf

[Ramy]

Argh!!! Another fatality which may have been avoided if we had better accident information sharing globally!

Ramy

[Andrew[_13_]]

I guess its too early to know what happened. But as a comment, I did
personally witness an inflight structural failure in a wooden glider back
in the
UK. It turned out to be caused by an effect called a 'compression shake'
which is when a compression overload leaves the wood with a fine defect
that
is very weak in tension, so it can fail in tension at a later time, maybe
years
later. These shakes can apparently be detected by a careful visual
examination, by someone who knows what to look for, eg after an unusually
heavy landing or shock. Also there is a BGA note about glue joint
inspections
in gliders like K7s. I don't know if the FAA pass these on to US owners.

http://www.gliding.co.uk/bgainfo/technical/inspections/042-07-2004-issue-
3.pdf

[[email protected]]

On Thursday, April 4, 2013 12:23:23 AM UTC-4, Ramy wrote:
> Argh!!! Another fatality which may have been avoided if we had better accident information sharing globally! Ramy

The accident that triggered the UK action was no secret and the findings were made available, even if not widely published on RAS.
No new findings resulted. It did trigger the requirement for more rigorous inspection.
One sad reality is that the few people who really know how to inspect and maintain old wood structure gliders are fading away. The new A&P's and IA's are very well versed in documentation, but not so well trained in some of these less used skills.
Sadly
UH

[Steve Leonard[_2_]]

On Wednesday, April 3, 2013 11:23:23 PM UTC-5, Ramy wrote:
> Argh!!! Another fatality which may have been avoided if we had better accident information sharing globally! Ramy

Maybe and maybe not, Ramy. If you have not yet, I would encourage you to go read the report on the one in the UK. The wing failed about one meter outboard of the fuselage. Roughly where the drag spar attaches to the main spar. On this recent accident in Texas, the eyewitnesses say the wing failed at roughly half span.

It could well be that it was the same basic cause (compression fracture in the lower cap that reduced its tension load carrying capability), but as Hank noted, there are fewer and fewer good "wood people" out there. However, I know we have a couple of them assisting the NTSB with information, and how to access proper information for this investigation.

Steve

[[email protected]]

I don’t know if it played a role in this accident, but I do know firsthand that glue failure is a problem in Ka-7’s. When my club started to use a winch, we needed an appropriate two-seater fast, so we bought a cheap Ka-7.. We used it extensively during the 2007 season. However, at the end of the year, we decided to replace the decidedly worn fabric. As soon as we opened up the wing, biscuits began falling of the ribs. There were also other glue failures, for example at the double rib at the root of the ailerons. I wrote to Schleicher who confirmed that the glue was Kaurit, known to become brittle after a time. After consulting with a professional well versed in wooden aircraft, we considered it impossible to repair the airframe at a sensible cost and time expenditure. The glider was donated to a museum to show the internal organs. And we bought an Aerodux-glued ASK-13 to replace it....

http://imageshack.us/photo/my-images/35/biscuitsfallenoff01.jpg/

http://imageshack.us/photo/my-images/404/doubleribfailure.jpg/

[Steve Leonard[_2_]]

On Friday, April 5, 2013 12:02:52 PM UTC-5, wrote:
> I don’t know if it played a role in this accident, but I do know firsthand that glue failure is a problem in Ka-7’s. When my club started to use a winch, we needed an appropriate two-seater fast, so we bought a cheap Ka-7. We used it extensively during the 2007 season. However, at the end of the year, we decided to replace the decidedly worn fabric. As soon as we opened up the wing, biscuits began falling of the ribs. There were also other glue failures, for example at the double rib at the root of the ailerons. I wrote to Schleicher who confirmed that the glue was Kaurit, known to become brittle after a time. After consulting with a professional well versed in wooden aircraft, we considered it impossible to repair the airframe at a sensible cost and time expenditure. The glider was donated to a museum to show the internal organs. And we bought an Aerodux-glued ASK-13 to replace it....

And those with more experience with Schleicher sailplanes know that different glues were used in different places on the planes. It is doubtful that the same type of glue used to build the ribs was used to build the spars, the D-tube, or other wooden parts of the plane. Possible, but not too likely.

I, too, have seen gussets coming off of ribs on older Schleicher sailplanes.. Just like in your photos. But be careful about making the generalization that because there is an issue with the glue on the ribs that there is an issue with all the glue joints in the airplane.