Failed Maillon Report

Original at:
http://bhpa.co.uk/pdf/safety_notices/sn032.082011.pdf

Unformatted text:

British Hang Gliding
and Paragliding
Association Ltd
8 Merus Court
Meridian Business Park
Leicester LE19 1RJ
Tel (0116) 289 4316
Fax (0116) 281 4949
www.bhpa.co.uk
SAFETY NOTICE
Issued by Angus Pinkerton - Chairman of the Flying & Safety Committee 23 August 2011.
All paraglider power pilots, Instructors, Coaches and Safety Officers must READ, DIGEST AND TAKE
ACTION on the contents of this Notice and keep it for future reference.
If you hold a copy of the BHPA Technical Manual this notice must be inserted into it and retained until it is
withdrawn or superseded on instructions from the Chairman FSC.
3.5mm mAIllONS FITTEd TO wINgS FrOm
pArAmANIA mANuFACTurEd SINCE mArCh 2011
During the second flight of a brand new Paramania Revolution 2 paramotor wing the pilot
noticed one of his A riser maillons open up. He was able to carry out a safe landing.
Initial inspection of the maillon showed that the nut was correctly done up and the bottom
threaded section had been released.
Continued..........
Ref. no.: FSC.SN.32
Date: 08/2011
Pages: 2 (Pink)
b) There is considerable variation in the finished dimensions of these
maillons, particularly in the length of the nut and the size of the
opening. On nearly all of the maillons examined the nut length was
less than that shown on the design drawing, and the opening was
larger. This has the effect of significantly reducing the number of
threads actually engaged on the bottom threaded member. (The
design shows four threads engaged over a 4mm length. On two
of the maillons examined the actual distance engaged was less than
2.40mm.)
Continued..........
Further detailed examination and testing of the failed maillon and other identical maillons
has revealed that:
a) The failed maillon had improperly formed threads on the lower
threaded component (manufacturing defect).
c) This particular maillon type is manufactured in Taiwan by ‘Pro-Metal’.
This maillon type has been fitted to other glider types from other
manufacturers but, with the co-operation of the manufacturing
company, all of the affected gliders have been accounted for. Improved
quality control procedures have also been put in place to ensure that
defective maillons do not get incorporated into new gliders in future.
The BHPA Flying and Safety Committee advise that any pilot who has a Paramania wing
manufactured since the beginning of March 2011 fitted with 3.5mm maillons should contact
their dealer for details of the checking and replacement procedures Paramania have
established for ensuring the airworthiness of the maillons fitted to their wing.