Click-Lock Finsterwalder buckles
Tens of thousands of paragliding and paramotoring harnesses have been potentially ruled un-airworthy following a safety notice from buckle-maker Finsterwalder.
The company, which supplies buckles to dozens of harness manufactures, issued a safety notice about Click-Lock and T-Lock buckles at the start of June.
Since then, it has become clear that thousands of harnesses will be affected.
The safety notice affects all harnesses more than four-years-old that use a Finsterwalder Click-Lock or T-Lock buckling system on the chest-strap.
The issue is that the hooks on the plug end of the buckle wear out over time and under pressure, resulting in a possible accidental opening.
The issue is thought to have been the reason behind a fatal accident in Italy a month ago. In that accident the pilot was leaning forwards when approaching landing when the chest strap Click-Lock buckle opened unintentionally. He fell out of his harness and was killed. He was thought to be flying a harness that was 10 years old.
In a separate incident earlier this year a pilot was in a SAT when his Click-Lock buckle opened under pressure. The pilot was able to re-buckle the chest-strap in flight and landed safely without injury.
Following the incidents Finsterwalder conducted an investigation and found that the hooks on the metal tongue can wear out through the frequent diagonal load changes found in flight. This results in rounded hooks, instead of flat.
Over time, the buckles round-out, which means they can come undone unintentionally. The harness strap is always under pressure, so it is happening all the time as you fly. Image: Finsterwalder
The problem has only been found in Click-Lock buckles, but since T-Lock buckles use the same system Finsterwalder issued a safety notice on both.
That notice says that the buckles should not be used if they are more than four-years-old: the harnesses should not be flown.
If the harness is between four- and 10-years-old, the buckles can be re-worked by the harness manufacturer to make them airworthy again.
If the harness is more than 10-years-old, the buckles are not airworthy and should not be re-worked. The harness should not be flown.
Re-working the buckles in a vice
Thomas Finsterwalder from Finsterwalder said he expected thousands of harnesses to be affected.
“We think 8,000 harnesses sold by Advance have been affected. And we have sold even more buckles to Woody Valley.”
In total Finsterwalder has informed 43 companies who use their buckles of the problem.
Some manufacturers however use buckles from other suppliers that are based on or are copies of the original Finsterwalder design. Those buckles are not subject to a manufacturers’ safety notice, but could theoretically have the same problem.
Individual manufacturers have started to issue their own safety warnings about their own harnesses.
For example, Advance have issued a safety notice for six models, including the Advance Impress, Impress 2 and Impress 2+.
Advance have also issued a ‘quick fix’ and advice on how they can ‘re-finish‘ a Finsterwalder buckle so it is safe again.
Separately, the DHV, Germany’s free flight association, have added their stamp of approval to the re-finishing suggested by Finsterwalder. “The DHV has refinished faulty harness buckles as recommended, and now cannot simulate an undesired opening of the buckle,” they say on their website.
Advice for pilots:
– Identify what type of buckles are used on your harness chest strap. The safety notice affects Finsterwalder Click-Lock and T-Lock buckles
– If your harness has these buckles and it is four-years-old or more (June 2012), don’t fly it. Contact the manufacturer through their website or dealer to find out what to do.
– If you think your buckles are Click-Lock or T-Lock clones, contact your manufacturer for advice.
– If the Click-Lock or T-Lock buckles on your harness are 10-years-old or more, then they are not air-worthy and should not be re-worked – do not fly the harness.
Advance, AVA Sport, APCO, Finsterwalder & Charly, Karpo Fly, Sky Paragliders, SkyTrekking, Sol and Woody Valley are manufacturers named by the DHV that use the Finsterwalder buckles. The same buckles are also used in some paramotoring harnesses.
