Crotch strap for ASW 15?

Is there any way technically and legally to add a fifth strap to an ASW 15? No matter how tight I pull the lap belts they ride up when ridge flying allowing the shoulder straps to become loose. My head is pretty close to the canopy and a stiff jolt can lead to head banging if the harness becomes loose. I also know having the lap belts out of position can be very dangerous in the event of a crash and would love to alleviate these problems. mdfaddenatgmaildotcom

On Mar 4, 5:48*pm, wrote:
Is there any way technically and legally to add a fifth strap to an ASW 15? No matter how tight I pull the lap belts they ride up when ridge flying allowing the shoulder straps to become loose. My head is pretty close to the canopy and a stiff jolt can lead to head banging if the harness becomes loose. I also know having the lap belts out of position can be very dangerous in the event of a crash and would love to alleviate these problems. mdfaddenatgmaildotcom

It depends on how the glider is certificated. If it has a Special
Airworthiness Certificate issued for the operation of an experimental,
racing aircraft like many early European imports, then an A&P (or
perhaps even you depending on the specific verbiage in the Operating
Limitations that are part of the airworthiness certificate) can find
some stout piece of structure in an appropriate spot to add the fifth
point anchor. Seek the guidance of a reputable glider repair shop, use
good practices according to AC43.13, and it will probably be fine.

If it is type certificated and carries a standard airworthiness
certificate, then it is is more complicated but still doable. You will
probably need to do a form 337, for which you will need the counsel of
an A&P or IA.

Thinks like this are why I prefer to mess around with experimental,
amateur-built sailplanes. Once the Phase I testing hours have been
flown off, the usual operating limitations are typically no different
from those of any other sailplane. However, you can maintain, repair,
modify, and inspect it yourself.

Thanks, Bob K.
http://www.hpaircraft.com/hp-24
https://www.facebook.com/pages/HP-24...t/200931354951

On Monday, March 4, 2013 8:48:26 PM UTC-5, wrote:
Is there any way technically and legally to add a fifth strap to an ASW 15? No matter how tight I pull the lap belts they ride up when ridge flying allowing the shoulder straps to become loose. My head is pretty close to the canopy and a stiff jolt can lead to head banging if the harness becomes loose. I also know having the lap belts out of position can be very dangerous in the event of a crash and would love to alleviate these problems. mdfaddenatgmaildotcom

I have done several installations of a 5th point in Schleicher gliders, but not an ASW-15.
I'll use '19 as an example.
First, you must use a harness assembly intended for the purpose with a receptacle for the added point. You may have to replace your harness.
Procure the additional belt intended to be used with that harness. No home made stuff.
The belt is secured to the bulkhead that mounts the aft end of the control stick. This means it will be a bit, about 2 inches off to one side, and will be near the aft edge of the stick boot. It comes up through a hole about 2 1/4 by 1/2 in the seat pan. On some gliders the belt can wrap around a convenient feature. On others you will need to put in a fitting.
Care must be taken not to interfere with controls and proper anchoring, but this is not rocket science.
There is no reason that this would be considered anything other than a minor modification as long as the original harness mounting is not affected.
It may pay to ask Schleicher if they have instructions, however I doubt it.
Good luck
UH

Here's how I did it in my LS-6a about 20 years ago:

I was given the brand new 5-point harness intended to be installed in a 1-34
which had recently crashed. I installed the shoulder and waist straps in
their normal locations. For the crotch strap, I procured the biggest steel
bumper washer I could find at the local hardware store and glued it to the
under side of the seat pan in a good location using flox and bi directional
glass and epoxy. I drilled through the washer and seat pan and, using grade
8 bolt, another couple of washers, and a locking nut, secured the belt
mounting piece to the floor of the seat pan. Of course, the LS-6 was
Experimental.

When he crashed several years later, my partner told me that it's his firm
belief that that fifth strap saved his life.

I'm not a mechanic and the above is not advice, only a description of how I
did it.

I once installed an oxygen system in my ASW-19 and had my IA submit a 337.
The FAA rejected it on the basis of "no reference to manufacturer's
installation instructions". But that was a Standard Airworthiness aircraft.


wrote in message
...
On Monday, March 4, 2013 8:48:26 PM UTC-5, wrote:
Is there any way technically and legally to add a fifth strap to an ASW
15? No matter how tight I pull the lap belts they ride up when ridge
flying allowing the shoulder straps to become loose. My head is pretty
close to the canopy and a stiff jolt can lead to head banging if the
harness becomes loose. I also know having the lap belts out of position
can be very dangerous in the event of a crash and would love to alleviate
these problems. mdfaddenatgmaildotcom

I have done several installations of a 5th point in Schleicher gliders, but
not an ASW-15.
I'll use '19 as an example.
First, you must use a harness assembly intended for the purpose with a
receptacle for the added point. You may have to replace your harness.
Procure the additional belt intended to be used with that harness. No home
made stuff.
The belt is secured to the bulkhead that mounts the aft end of the control
stick. This means it will be a bit, about 2 inches off to one side, and will
be near the aft edge of the stick boot. It comes up through a hole about 2
1/4 by 1/2 in the seat pan. On some gliders the belt can wrap around a
convenient feature. On others you will need to put in a fitting.
Care must be taken not to interfere with controls and proper anchoring, but
this is not rocket science.
There is no reason that this would be considered anything other than a minor
modification as long as the original harness mounting is not affected.
It may pay to ask Schleicher if they have instructions, however I doubt it.
Good luck
UH

My current harness is a Schroth equipped for a fifth strap. However, my understanding is that they supply only manufacturers now, not re-sellers. Will the tab on other belts fit a Schroth buckle? I barely fit into my cockpit lengthwise. I completely remove the adjustable seatback so my head won't hit the canopy. This results in a slightly more reclined (and very comfortable)seating position making it easier for the lap belt to ride up. The ASW 15's cockpit doesn't have anything that forces you to bend your knees or stop you from "submarining" in the event of a sudden stop. I'm concerned about being legal but more concerned with being safe I've read more than one account (like the one above) where pilots credit the fifth strap with saving their lives or preventing serious injury.

Mike

mdfaddenatgmaildotcom

Contact the many places to buy parts. Somebody likely has the Schroth 5th point.
Otherwise there are lots of harnesses for sale on segelflug.de. Even if they're old, the webbing can be replaced.
Jim

I just went on the FAA registry site, and it looks like all or at
least most of the ASW-15 in the US are type certificated:

http://registry.faa.gov/aircraftinqu...W15&PageNo =1

If yours is among those, you should probably consult first with an A&P
or IA. If they are comfortable signing it off as a minor modification,
you're good to go. If not, they will probably be able to advise you
what hoops to jump through.

Thanks, Bob K.

On Tuesday, March 5, 2013 2:24:09 PM UTC-5, wrote:
I completely remove the adjustable seatback so my head won't hit the canopy. This results in a slightly more reclined (and very comfortable)seating position making it easier for the lap belt to ride up. The ASW 15's cockpit doesn't have anything that forces you to bend your knees or stop you from "submarining" in the event of a sudden stop.

Does your POH allow you to remove the seatback and thereby create a submarining possibility? This also shifts the CG aft.

Some POH allow the removal of the seatback to accommodate a large pilot, so you might be technically okay.

My solution to the 'riding up' problem would be to position the lapbelt below my beer belly where it would be held firmly in place. (just kidding)

Have you considered a six-point? No modification was necessary for my -20, and it'll make peeing easier.

Jim

On Tuesday, March 5, 2013 6:51:58 PM UTC-5, J. Murray wrote:
Have you considered a six-point? No modification was necessary for my -20, and it'll make peeing easier.



Jim

I posted a bunch of stuff on this topic a few years back, as have others. Search for "Crotch Strap" and "6 Point Harness" within rec.aviation.soaring.

P3