World Wide 119 Grounding?
Joined: Jun 2008
Posts: 1,413
Likes: 0
From: England & Scotland
There is no current EAD in the UK listed for the 119
Avoid imitations
Joined: Nov 2000
Aviation Qualifications: ATPL
Posts: 15,110
Likes: 1,083
From: Wandering the FIR and cyberspace often at highly unsociable times
Four attachment nuts need changing; that's really all there is to it. The nuts are used elsewhere on the aircraft and there have already been a number of previous "BTs" requiring them to be changed in other locations.
I understand only certain batch numbers of nuts are involved; it's a problem with hydrogen embrittlement.
I understand only certain batch numbers of nuts are involved; it's a problem with hydrogen embrittlement.
Joined: Oct 1999
Aviation Qualifications: ATPL
Posts: 7,371
Likes: 926
From: Den Haag
Joined: Jul 2010
Posts: 339
Likes: 1
From: Shelton WA.
These are a commonly used series of nuts, yet this seems to be recurring problem (on other types) that crops up every five or six years or so. Maybe it's about time to dump them. Anyone else remember other occurrences?
Joined: Jul 2010
Posts: 339
Likes: 1
From: Shelton WA.
EASA Reports EASA_EAD 9/20/2013
EASA stated that a technical investigation reported that cracks in a MS21042L4 nut connecting a Thomas coupling with the splined adapter on AW100SP helicopters were believed to have been caused by hydrogen embrittlement.
EASA_EAD 10/30/2013
EASA stated that two MS21042-4 nuts connected to the swashplate support to the upper case of the main transmission of a A190S helicopter were found cracked. They stated the nuts in use were deficient with evidence of hydrogen embrittlement.
EASA_EAD 5/02/2014
Observed a cracked MS21042L4 which connected a flexible coupling with the coupling adapter on a AB 206 helicopter. EASA stated the deficiency was due to hydrogen embrittlement.
EASA_EAD 5/07/2014
EASA expanded the EAD above to include AB 212, AB 412, and AB 412EP helicopters.
EASA_EAD 5/13/2014
EASA expanded the EAD to include MS21042-5 nuts found on the flexible coupling. Pictures are included showing the location of the cracked nuts.
Plus NZ CAA June 2010.
Robinson R22 Jan 2014.
CASA Australia Sep 2014.
..and on and on.
EASA stated that a technical investigation reported that cracks in a MS21042L4 nut connecting a Thomas coupling with the splined adapter on AW100SP helicopters were believed to have been caused by hydrogen embrittlement.
EASA_EAD 10/30/2013
EASA stated that two MS21042-4 nuts connected to the swashplate support to the upper case of the main transmission of a A190S helicopter were found cracked. They stated the nuts in use were deficient with evidence of hydrogen embrittlement.
EASA_EAD 5/02/2014
Observed a cracked MS21042L4 which connected a flexible coupling with the coupling adapter on a AB 206 helicopter. EASA stated the deficiency was due to hydrogen embrittlement.
EASA_EAD 5/07/2014
EASA expanded the EAD above to include AB 212, AB 412, and AB 412EP helicopters.
EASA_EAD 5/13/2014
EASA expanded the EAD to include MS21042-5 nuts found on the flexible coupling. Pictures are included showing the location of the cracked nuts.
Plus NZ CAA June 2010.
Robinson R22 Jan 2014.
CASA Australia Sep 2014.
..and on and on.
Last edited by Gemini Twin; 31st October 2014 at 17:45. Reason: typo.
Joined: Jul 2001
Posts: 1,383
Likes: 1
From: ...in view of the 'Southern Cross' ...
Mmmm ...
For those interested ... go here for pic of the real items ... heat resistant self locking nuts ...
MS21042 ALL-METAL STOP NUTS from Aircraft Spruce
For those interested ... go here for pic of the real items ... heat resistant self locking nuts ...
MS21042 ALL-METAL STOP NUTS from Aircraft Spruce
Joined: Jul 2010
Posts: 211
Likes: 0
From: Wrong Town
Robinson. Them of Flimsycopter designs'r'us are getting rid of these nuts entirely.
http://www.robinsonheli.com/service_...s/r22_sl64.pdf
http://www.robinsonheli.com/service_...s/r22_sl64.pdf
Joined: Apr 2008
Posts: 218
Likes: 52
From: Europe
The issue with MS21042 nuts (and some other hardware) is dragging on for some time. Several AD`s issued against different installations on same and/or different heli types but almost allways same PN - and it seems all coming from single manufacturer, based in Ohio, USA. (correct me if I am wrong)
I am watching in disbelief, how this issue is handled so far by EASA, FAA.....
EASA issued an SIB 2012-06 Rev. 2 EASA Airworthiness Directives Publishing Tool
that was mentioning the issue sometime ago - and yet problems keeps on coming. I am afraid this will continue so until more serious consequences result from cracked hardware, that is installed in many many places, some critical.
Robinson seems to be the only one, that took the only reasonable measure.
If you can`t trust the basic nut and bolt, then there is a real problem.
regards,
hoistop
I am watching in disbelief, how this issue is handled so far by EASA, FAA.....
EASA issued an SIB 2012-06 Rev. 2 EASA Airworthiness Directives Publishing Tool
that was mentioning the issue sometime ago - and yet problems keeps on coming. I am afraid this will continue so until more serious consequences result from cracked hardware, that is installed in many many places, some critical.
Robinson seems to be the only one, that took the only reasonable measure.
If you can`t trust the basic nut and bolt, then there is a real problem.
regards,
hoistop