Tost Ring Failure

On Sunday, June 11, 2017 at 7:37:42 PM UTC-4, Sean Franke wrote:
On Sunday, June 11, 2017 at 1:00:04 PM UTC-7, Benedict Smith wrote:
The failures I have seen are not in the tost ring pair at the glider end of
the
strop but the ones further down that connect the strop to the drogue or on

either side of the weak link (a circular ring that the strop is spliced to
and is
coupled to the oval Tost link with the quick release flat), as these are an

integral part of the quick release link I assume that they should be a
genuine
Tost part, but several I have seen are welded construction and don't have
any
visible markings on them. (This is in the UK)


At 15:52 11 June 2017, Tango Eight wrote:
On Sunday, June 11, 2017 at 11:34:20 AM UTC-4, howard banks wrote:
Would some kind soul who really knows please tell us whether genuine
Tost
rings are ever(a) welded or (b) oval?

The correct rings are stamped LN 65091 on the big ring. The most recent
production also have TOST stamped on them. The big ring is oval, the
little ring is round.

30+ years ago, there was a different Tost ring set in use. It is not
stamped with the LN 65091 designation. It is obsolete and should not be
used.

best,
Evan Ludeman / T8


Tost Connecting Rings do not have a weld. Tost states that type certification stipulates that every Tost tow release must be operated only with a ring pair meeting the LN 65091 aeronautical standard. Connecting ring pairs must be stamped with the manufacturer's name and the standard number.

WELDED RINGS ARE GENERALLY PROHIBITED. Use of welded rings voids tow release warranties. Welded rings cause damage to tow releases. Undersized rigs can lead to tow release jamming.

Connecting rings must be visually checked and measured at regular intervals. Rings pairs that deviate from standard dimensions must be replaced.

See a ring pair picture he http://wingsandwheels.com/aircraft-p...tow-rings.html

Sean Franke

See my note above. The picture clearly shown the weld in the large ring....