BRS chutes. Why doesn't everyone use them?

On Jan 25, 7:05*pm, Tony V wrote:
Correction!

I was just taken to task by a hang glider (and sailplane) pilot
friend......

Hang gliders use "hand thrown" chutes, not "ballistic".

Cookie

Happily, everybody is right. :-) both hand-thrown and ballistic chutes
are available to the hang glider community. Seehttp://www.highenergysports.com/articles/ballistic_controversy.htmfor a
start

Tony LS6-b, USHPA 7826

Yes, according to my expert, both ballistic and hand thrown parachutes
have been and are used on hang gliders. But mostly hand thrown by a
large margin.

But my original point was that hang gliders widely use parachute
recovery systems, you could say "everybody uses them" and you could
say they are "mandated". I believe that the hang glider people have
decided to self regulate (as opposed to government regulation) and
require chutes at any "sanctioned" gliding site.

This is not the case in sailplanes however, for the reasons given in
this thread. Sailplanes are very different in some respects, than
hang gliders. I think that the "personal" parachute is the preferred
solution for sailplanes. Soaring also self regulates to some degree
as chutes are required in contests.

Cookie

On Jan 25, 7:48*pm, Andy wrote:
On Jan 25, 8:05*am, BruceGreeff wrote:

I have seen an ASW20 where the wings departed the fuselage together-
ripping the main spar out of the fuselage.

As a Schleicher driver I'm interested to know what failed. * How did
the wings separate from the fuselage but remain together? *Did all the
lift pins fail, or did the lift pin sockets in the wing roots fail, or
was there somehow sufficient bending of the spar that the lift pins
detached without the pins or sockets failing. *Maybe the whole lift
pin carry through structure detached from the fuselage but isn't it
attached to the landing gear?

I'd always assumed the spar would break before any of that could
happen but I know the 20 spar is more flexible than some.

Andy

Interesting about the mode of structural failure on sailplanes. To
the defense of BRS...From what I learned in my research for possiblly
installing a BRS system into my homebuilt ...the BRS guys do a lot of
research and testing. It is not so simple as just hooking the
parachute onto some convenient spot on the aircraft. I have not seen
the details on the BRS set up for sailplanes, but on my airplane I
had originally expected that the parachute would be connected to the
center section of the top wing spar......I soon learned that this was
a bad idea and not how it is done. The BRS design called for kevlar
straps under the pilot and passenger section of the fuselage......In
theory, the wings could fall off, the tail could fall off ,the engine
could fall off and the passenger section could be severly damaged, and
still return the occupants to earth relatively unharmed.

I would not expect to see a recovery chute attached to the spars, or
spar stubs in a glider.....rather somehow strapping under the
passenger area of the cockpit.

Cookie

On Jan 25, 7:47*pm, Andreas Maurer wrote:
On Tue, 25 Jan 2011 16:48:29 -0800 (PST), Andy
wrote:



As a Schleicher driver I'm interested to know what failed. * How did
the wings separate from the fuselage but remain together? *Did all the
lift pins fail, or did the lift pin sockets in the wing roots fail, or
was there somehow sufficient bending of the spar that the lift pins
detached without the pins or sockets failing. *Maybe the whole lift
pin carry through structure detached from the fuselage but isn't it
attached to the landing gear?

Hi Andy,

Schleicher gliders have a notorious weak point: The bushings that hold
the lift pins are a little bit too short and not fixed in the shear
force tube - there have been a number of accidents where they were
twisted and ripped out of the shear force tube instead of keeping the
wing attached. (I hope I got the technical terms halfways correctly).

However, I'm not aware of such a thing happening inflight, but it
happened a couple of times after a wing hit a tree and an extremely
hard impact. I'm pretty sure *that strong wing flutter exhibits forces
that are sufficient.

In Schleicher gliders, the structure that carries the wing is not
directly attached to the landing gear (as ist is the case with most
Schempp-Hirth gliders).

One thing should be mentioned: I have the impression that the
Schleicher design is - despite the problem with the bushings - one of
the strongest - in case of a crash the wings of Schleicher gliders
stay attached to the fuselage comparably often.

Andreas

Thanks for that information Andreas.

Andy

On Jan 25, 8:27*pm, "
wrote:
On Jan 25, 7:48*pm, Andy wrote:





On Jan 25, 8:05*am, BruceGreeff wrote:

I have seen an ASW20 where the wings departed the fuselage together-
ripping the main spar out of the fuselage.

As a Schleicher driver I'm interested to know what failed. * How did
the wings separate from the fuselage but remain together? *Did all the
lift pins fail, or did the lift pin sockets in the wing roots fail, or
was there somehow sufficient bending of the spar that the lift pins
detached without the pins or sockets failing. *Maybe the whole lift
pin carry through structure detached from the fuselage but isn't it
attached to the landing gear?

I'd always assumed the spar would break before any of that could
happen but I know the 20 spar is more flexible than some.

Andy

Interesting about the mode of structural failure on sailplanes. *To
the defense of BRS...From what I learned in my research for possiblly
installing a BRS system into my homebuilt ...the BRS guys do a lot of
research and testing. * It is not so simple as just hooking the
parachute onto some convenient spot on the aircraft. *I have not seen
the details on *the BRS set up for sailplanes, but on my airplane I
had originally expected that the parachute would be connected to the
center section of the top wing spar......I soon learned that this was
a bad idea and not how it is done. *The BRS design called for kevlar
straps under the pilot and passenger section of the fuselage......In
theory, the wings could fall off, the tail could fall off ,the engine
could fall off and the passenger section could be severly damaged, and
still return the occupants to earth relatively unharmed.

I would not expect to see a recovery chute attached to the spars, or
spar stubs in a glider.....rather somehow strapping under the
passenger area of the cockpit.

Cookie- Hide quoted text -

- Show quoted text -

The Genesis 2 was designed to use a BRS and the web-harness is
attached to all 4 lift fittings just inside the fuselage. The system
was never tested, but should bring the ship down in a mostly wings
level attitude. The hatch is located to allow the risers to deploy
with minimum damage to surrounding area. At least one Genesis is
flying with this setup. I was ready to buy last fall, but never heard
back from several inquires. Has anybody had recent contact with BRS?
JJ